tag:theconversation.com,2011:/id/topics/toxicology-7879/articlesToxicology – The Conversation2024-03-18T19:21:57Ztag:theconversation.com,2011:article/2253542024-03-18T19:21:57Z2024-03-18T19:21:57ZStudy links microplastics with human health problems – but there’s still a lot we don’t know<figure><img src="https://images.theconversation.com/files/582403/original/file-20240317-28-ha8xio.jpg?ixlib=rb-1.1.0&rect=62%2C0%2C7008%2C4668&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/microplastics-hand-air-pollution-aquatic-food-2164471827">Naiyana Somchitkaeo/Shutterstock</a></span></figcaption></figure><p>A <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa2309822">recent study</a> published in the prestigious New England Journal of Medicine has linked microplastics with risk to human health.</p>
<p>The study involved patients in Italy who had a condition called carotid artery plaque, where plaque builds up in arteries, potentially blocking blood flow. The researchers analysed plaque specimens from these patients. </p>
<p>They found those with carotid artery plaque who had microplastics and nanoplastics in their plaque had a higher risk of heart attack, stroke, or death (compared with carotid artery plaque patients who didn’t have any micro- or nanoplastics detected in their plaque specimens). </p>
<p>Importantly, the researchers didn’t find the micro- and nanoplastics <em>caused</em> the higher risk, only that it was correlated with it. </p>
<p>So, what are we to make of the new findings? And how does it fit with the broader evidence about microplastics in our <a href="https://www.science.org/doi/10.1126/sciadv.aax1157">environment</a> and <a href="https://www.sciencedirect.com/science/article/pii/S0160412022001258">our bodies</a>?</p>
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<h2>What are microplastics?</h2>
<p>Microplastics are plastic particles less than five millimetres across. Nanoplastics are less than one micron in size (1,000 microns is equal to one millimetre). The precise size classifications <a href="https://doi.org/10.1016/j.envpol.2018.01.024">are still a matter of debate</a>. </p>
<p>Microplastics and nanoplastics are created when everyday products – including clothes, food and beverage packaging, home furnishings, plastic bags, toys and toiletries – degrade. Many personal care products contain microsplastics in the form of microbeads.</p>
<p>Plastic is also used widely in agriculture, and can degrade over time into microplastics and nanoplastics.</p>
<p>These particles are made up of common polymers such as polyethylene, polypropylene, polystyrene and polyvinyl chloride. The constituent chemical of polyvinyl chloride, vinyl chloride, is <a href="https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsDetails.aspx?faqid=281&toxid=51">considered carcinogenic</a> by the <a href="https://19january2017snapshot.epa.gov/sites/production/files/2016-09/documents/vinyl-chloride.pdf">US Environmental Protection Agency</a>.</p>
<p>Of course, the actual risk of harm depends on your level of exposure. As toxicologists are fond of <a href="https://onlinelibrary.wiley.com/doi/10.1111/bcpt.12622">saying</a>, it’s the dose that makes the poison, so we need to be careful to not over-interpret emerging research.</p>
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Read more:
<a href="https://theconversation.com/australians-are-washing-microplastics-down-the-drain-and-its-ending-up-on-our-farms-223079">Australians are washing microplastics down the drain and it's ending up on our farms</a>
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<h2>A closer look at the study</h2>
<p>This new study in the New England Journal of Medicine was a small cohort, initially comprising 304 patients. But only 257 completed the follow-up part of the study 34 months later. </p>
<p>The study had a number of limitations. The first is the findings related only to asymptomatic patients undergoing carotid endarterectomy (a procedure to remove carotid artery plaque). This means the findings might not be applicable to the wider population.</p>
<p>The authors also point out that while exposure to microplastics and nanoplastics has been likely increasing in recent decades, heart disease rates have been <a href="https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.115.015293">falling</a>.</p>
<p>That said, the fact so many people in the study had detectable levels of microplastics in their body is notable. The researchers found detectable levels of polyethylene and polyvinyl chloride (two types of plastic) in excised carotid plaque from 58% and 12% of patients, respectively. </p>
<p>These patients were more likely to be younger men with diabetes or heart disease and a history of smoking. There was no substantive difference in where the patients lived.</p>
<p>Inflammation markers in plaque samples were more elevated in patients with detectable levels of microplastics and nanoplastics versus those without. </p>
<figure class="align-center ">
<img alt="Plastic bottles washed up on a beach." src="https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Microplastics are created when everyday products degrade.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/close-waste-beach-1234533793">JS14/Shutterstock</a></span>
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<p>And, then there’s the headline finding: patients with microplastics and nanoplastics in their plaque had a higher risk of having what doctors call “a primary end point event” (non-fatal heart attack, non-fatal stroke, or death from any cause) than those who did not present with microplastics and nanoplastics in their plaque.</p>
<p>The authors of the study note their results “do not prove causality”.</p>
<p>However, it would be remiss not to be cautious. The history of environmental health is replete with examples of what were initially considered suspect chemicals that avoided proper regulation because of what the US National Research Council refers to as the “<a href="https://nap.nationalacademies.org/catalog/12209/science-and-decisions-advancing-risk-assessment">untested-chemical assumption</a>”. This assumption arises where there is an absence of research demonstrating adverse effects, which obviates the requirement for regulatory action. </p>
<p>In general, more research is required to find out whether or not microplastics cause harm to human health. Until this evidence exists, we should adopt the precautionary principle; absence of evidence should not be taken as evidence of absence.</p>
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Read more:
<a href="https://theconversation.com/were-all-ingesting-microplastics-at-home-and-these-might-be-toxic-for-our-health-here-are-some-tips-to-reduce-your-risk-159537">We're all ingesting microplastics at home, and these might be toxic for our health. Here are some tips to reduce your risk</a>
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<h2>Global and local action</h2>
<p>Exposure to microplastics in our home, work and outdoor environments is inevitable. Governments across the globe have started to acknowledge we must intervene. </p>
<p>The <a href="https://www.un.org/en/climatechange/nations-agree-end-plastic-pollution">Global Plastics Treaty</a> will be enacted by 175 nations from 2025. The treaty is designed, among other things, to limit microplastic exposure globally. Burdens are greatest <a href="https://doi.org/10.1016/j.envpol.2022.119957">especially in children</a> and especially those in low-middle income nations. </p>
<p>In Australia, legislation <a href="https://www.epa.vic.gov.au/about-epa/our-programs-and-projects/single-use-plastics-ban">ending single use plastics</a> will help. So too will the increased rollout of <a href="https://recyclingnearyou.com.au/containerdeposit/">container deposit schemes</a> that include plastic bottles.</p>
<p>Microplastics pollution is an area that requires a collaborative approach between researchers, civil societies, industry and government. We believe the formation of a “microplastics national council” would help formulate and co-ordinate strategies to tackle this issue.</p>
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Read more:
<a href="https://theconversation.com/the-problem-with-oodies-hooded-blankets-are-cosy-but-they-are-not-great-for-oceans-or-our-health-163087">The problem with Oodies: hooded blankets are cosy but they are not great for oceans or our health</a>
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<p>Little things matter. Small actions by individuals can also translate to significant overall environmental and human health benefits. </p>
<p>Choosing natural materials, fabrics, and utensils not made of plastic and disposing of waste thoughtfully and appropriately – including recycling wherever possible – is helpful.</p><img src="https://counter.theconversation.com/content/225354/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Patrick Taylor is a full-time employee of EPA Victoria, appointed to the statutory role of Chief Environmental Scientist.
He previously received funding via an Australian Government Citizen Science Grant (2017-2020), CSG55984 ‘Citizen insights to the composition and risks of household dust’ (the DustSafe project). Outputs from this project included published work on microplastics with Drs Neda Sharifi Soltani and Scott Wilson who were at Macquarie University at that time.
</span></em></p><p class="fine-print"><em><span>Scott P. Wilson works for the Australian Microplastic Assessment Project run by the not for profit organisation the Total Environment Centre. He has previously received funding from the NSW EPA for research into microplastic source tracking in Deewhy Lagoon and for developing a Microlitter Reduction Framework. </span></em></p>Microplastics are created when everyday products – including clothes, food and beverage packaging, home furnishings, plastic bags, toys and toiletries – degrade.Mark Patrick Taylor, Chief Environmental Scientist, EPA Victoria; Honorary Professor, School of Natural Sciences, Macquarie UniversityScott P. Wilson, Research Director, Australian Microplastic Assessment Project (AUSMAP); Honorary Senior Research Fellow, School of Natural Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2140602023-10-13T18:01:21Z2023-10-13T18:01:21ZWildfire smoke leaves harmful gases in floors and walls − air purifiers aren’t enough, new study shows, but you can clean it up<p>When wildfire smoke turns the air brown and hazy, you might think about heading indoors with the windows closed, running an air purifier or even wearing a mask. These are all good strategies to reduce exposure to the particles in wildfire smoke, but smoky air is also filled with potentially harmful gases. Those gases can get into buildings and remain in the walls and floors for weeks.</p>
<p>Getting rid of these gases isn’t as simple as turning on an air purifier or opening a window on a clear day.</p>
<p>In a new study published in the journal Science Advances, colleagues and I tracked <a href="https://www.science.org/doi/10.1126/sciadv.adh8263">the life of these gases</a> in a home exposed to wildfire smoke. We also found that the best way to get rid of the risk is among the simplest: start cleaning.</p>
<h2>The challenge of smoke particles and gases</h2>
<p>In December 2021, several of my friends and colleagues were affected by the <a href="https://theconversation.com/homes-that-survived-the-marshall-fire-1-year-ago-harbored-another-disaster-inside-heres-what-weve-learned-about-this-insidious-urban-wildfire-risk-196926">Marshall Fire</a> that burned about 1,000 homes in Boulder County, Colorado. The “lucky” ones, whose homes were still standing, asked me what they should do to clean their houses. I am <a href="https://scholar.google.com/citations?user=XpzGDEUAAAAJ&hl=en">an atmospheric and indoor chemist</a>, so I started looking into the published research, but I found very few studies on what happens after a building is exposed to smoke.</p>
<p>What scientists did know was that <a href="https://doi.org/10.1039/D1EM00087J">smoke particles end up on indoor surfaces</a> – floors, walls, ceilings. We knew that air <a href="https://doi.org/10.1080/02786826.2022.2054674">filters</a> could remove particles from the air. And colleagues and I were just beginning to understand that volatile organic compounds, which are traditionally thought to stay in the air, could actually <a href="https://doi.org/10.1126/sciadv.aay8973">stick to surfaces inside a home and build up reservoirs</a> – invisible pools of organic molecules that can contribute to the air chemistry inside the house.</p>
<p>Volatile organic compounds, or VOCs, are compounds that easily become gases at room temperature. They include everything from limonene in lemons to benzene in gasoline. VOCs aren’t always hazardous to human health, but <a href="https://doi.org/10.1021/acs.est.0c04497">many VOCs in smoke are</a>. I started to wonder whether the VOCs in wildfire smoke could also stick to the surfaces of a house.</p>
<h2>Tracking lingering risks in a test house</h2>
<p>I worked with researchers from across the U.S. and Canada to explore this problem during the <a href="https://indoorchem.org/projects/casa/">Chemical Assessment of Surfaces and Air</a>, or CASA, study in 2022. We built on <a href="https://doi.org/10.1039/C9EM00228F">HOMEChem</a>, a previous study in which we looked at how cooking, cleaning and occupancy could change indoor air.</p>
<p>In CASA, we studied what happens when pollutants and chemicals get inside our homes – pesticides, smog and even wood smoke.</p>
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<figcaption><span class="caption">Tracking VOCs from smoke and other sources.</span></figcaption>
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<p>Using a cocktail smoker and wood chips, we created a surprisingly chemically accurate proxy for wildfire smoke and released small doses into a <a href="https://www.nist.gov/el/net-zero-energy-residential-test-facility">test house</a> built by the National Institute of Standards and Technology. NIST’s house allowed us to conduct controlled chemistry experiments in a real-world setting.</p>
<p>We even aged the smoke in a large bag with ozone to simulate what happens when smoke travels long distances, like the smoke from Canadian wildfires that <a href="https://theconversation.com/wildfire-smoke-and-dirty-air-are-also-climate-change-problems-solutions-for-a-world-on-fire-207676">moved into the U.S.</a> in the summer of 2023. Smoke chemistry changes as it travels: <a href="https://doi.org/10.1021/acsearthspacechem.9b00125">Particles become more oxidized</a> and <a href="https://doi.org/10.1073/pnas.2012218117">brown</a>, while VOCs <a href="https://doi.org/10.1021/acs.est.1c05684">break down</a> and the smoke loses its distinctive smell.</p>
<h2>How VOCs behave in your home</h2>
<p>What we found in CASA was intriguing. While smoke particles quickly settled on indoor surfaces, <a href="https://www.science.org/doi/10.1126/sciadv.adh8263">VOCs were more insidious</a>.</p>
<p>At first, the house took up these smoke VOCs – on floors, walls and building surfaces. But once the initial smoke cleared, the house would slowly release those VOCs back out over the next hours, days or even months, depending on the type of VOC.</p>
<p>This release is what we call a partitioning process: During the smoke event, individual VOC molecules in the air attach to indoor surfaces with weak chemical bonds. The <a href="https://www.int-ads-soc.org/what-is-adsorption/">process is called adsorption</a>. As smoke clears and the air cleans out, the bonds can break, and molecules “desorb” back out into the air.</p>
<p><iframe id="v93H7" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/v93H7/10/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>We could watch this partitioning happen in the air by measuring smoke VOC concentrations. On surfaces, we could measure the weight of smoke VOCs that deposited on very sensitive balances and then were slowly released.</p>
<p>Overall, we concluded that this surface reservoir <a href="https://www.science.org/doi/10.1126/sciadv.adh8263">allows smoke VOCs to linger indoors</a>, meaning that people are exposed to them not just during the major smoke event but also long after.</p>
<h2>Why worry about VOCs?</h2>
<p>Smoke VOCs include well-known <a href="https://doi.org/10.1029/2021GH000546">carcinogens</a>, and high levels of exposure can induce <a href="https://theconversation.com/wildfire-smoke-can-harm-human-health-even-when-the-fire-is-burning-hundreds-of-miles-away-a-toxicologist-explains-why-206057">respiratory and health problems</a>.</p>
<p>While smoke VOC concentrations in our test house decreased with time, they remained persistently elevated above normal levels.</p>
<p>Given that <a href="https://doi.org/10.1021/acs.est.2c01381">VOC concentrations from other sources</a>, such as cooking and cleaning, can already be high enough in homes to harm health, this additional long-term exposure source from smoke could be important. Further toxicology studies will be needed to determine the significance of its health effects.</p>
<h2>How to clean up when smoke gets in</h2>
<p>So, what can you do to remove these lingering smoke gases?</p>
<p>We found that air purifiers can remove only some of the VOCs that are in the air – they can’t clean the VOCs on your floors or in your walls. They also work only when they’re running, and even then, air purifiers don’t work particularly well to reduce VOCs.</p>
<p>Opening windows to ventilate will clean the air, if it isn’t smoggy or smoky outside. But as soon as we closed windows and doors, smoke VOCs started to bleed off the surface reservoirs and into the air again, resulting in an elevated, near-constant concentration.</p>
<p>We realized that to permanently remove those smoke VOCs, we had to physically remove them from surfaces.</p>
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<img alt="A young scientist, wearing a face mask, and a large air purifier." src="https://images.theconversation.com/files/550124/original/file-20230925-19-s23qd0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/550124/original/file-20230925-19-s23qd0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/550124/original/file-20230925-19-s23qd0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/550124/original/file-20230925-19-s23qd0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/550124/original/file-20230925-19-s23qd0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/550124/original/file-20230925-19-s23qd0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/550124/original/file-20230925-19-s23qd0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">A scientist takes samples while running an air purifier in the test house. The results show the air purifier helps while it’s running, but only for gases in the air.</span>
<span class="attribution"><span class="source">John Eisele/Colorado State University</span></span>
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<p>The good news is that cleaning surfaces by vacuuming, dusting and mopping with a commercial, nonbleach solution did the trick. While some remediation companies may do this surface cleaning for you after extreme exposures, surface cleaning after any smoke event – like <a href="https://theconversation.com/north-americas-summer-of-wildfire-smoke-2023-was-only-the-beginning-210246">Canadian wildfire smoke</a> drifting into homes in 2023 – should effectively and permanently reduced smoke VOC levels indoors.</p>
<p>Of course, we could reach only a certain number of surfaces – it’s hard to vacuum the ceiling! That meant that surface cleaning improved but didn’t eliminate smoke VOC levels in the house. But our study at least provides a path forward for cleaning indoor spaces affected by air pollutants, whether from wildfires, chemical spills or other events. </p>
<p>With wildfires <a href="https://www.unep.org/news-and-stories/story/air-pollution-wildfires-expected-surge-world-warms">becoming more frequent</a>, surface cleaning can be an easy, cheap and effective way to improve indoor air quality.</p><img src="https://counter.theconversation.com/content/214060/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Delphine Farmer receives funding from the Alfred P. Sloan Foundation, W.M. Keck Foundation, National Science Foundation, Department of Energy, and the National Oceanic and Atmospheric Administration.</span></em></p>Wildfire smoke, even from fires far away, carries potentially harmful gases that, once inside, tend to stick around. An air quality specialist offers an easy, cheap, effective way to deal with it.Delphine Farmer, Professor of Chemistry, Colorado State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2104622023-08-10T20:00:53Z2023-08-10T20:00:53ZWhat’s in vapes? Toxins, heavy metals, maybe radioactive polonium<figure><img src="https://images.theconversation.com/files/541174/original/file-20230804-29-77kck2.jpg?ixlib=rb-1.1.0&rect=1%2C1%2C997%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-girl-smokes-disposable-electronic-cigarette-1943062066">Shutterstock</a></span></figcaption></figure><p>If you asked me what’s in e-cigarettes, disposable vapes or e-liquids, my short answer would be “we don’t fully know”.</p>
<p>The huge and increasing range of products and flavours on the market, changes to ingredients when they are heated or interact with each other, and inadequate labelling make this a complicated question to answer.</p>
<p><a href="https://www.annualreviews.org/doi/pdf/10.1146/annurev-anchem-061318-115329">Analytical chemistry</a>, including <a href="https://www.mja.com.au/journal/2022/216/1/chemical-analysis-fresh-and-aged-australian-e-cigarette-liquids">my own team’s research</a>, gives some answers. But understanding the health impacts adds another level of complexity. E-cigarettes’ risk to health varies depending on <a href="https://pubs.acs.org/doi/abs/10.1021/acs.chemrestox.1c00070">many factors</a> including which device or flavours are used, and how people use them.</p>
<p>So vapers just don’t know what they’re inhaling and cannot be certain of the health impacts.</p>
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Read more:
<a href="https://theconversation.com/no-vapes-arent-95-less-harmful-than-cigarettes-heres-how-this-decade-old-myth-took-off-203039">No, vapes aren't 95% less harmful than cigarettes. Here's how this decade-old myth took off</a>
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<h2>What do we know?</h2>
<p>Despite these complexities, there are some consistencies between what different laboratories find.</p>
<p>Ingredients include nicotine, flavouring chemicals, and the liquids that carry them – primarily propylene glycol and glycerine.</p>
<p><a href="https://www.industrialchemicals.gov.au/sites/default/files/2020-08/Non-nicotine%20liquids%20for%20e-cigarette%20devices%20in%20Australia%20chemistry%20and%20health%20concerns%20%5BPDF%201.21%20MB%5D.pdf">Concerningly</a>, we also find volatile organic compounds, particulate matter and carcinogens (agents that can cause cancer), many of which we know are harmful. </p>
<p>Our <a href="https://www.mja.com.au/journal/2019/210/3/nicotine-and-other-potentially-harmful-compounds-nicotine-free-e-cigarette">previous</a> <a href="https://www.mja.com.au/journal/2022/216/1/chemical-analysis-fresh-and-aged-australian-e-cigarette-liquids">research</a> also found 2-chlorophenol in about half of e-liquids users buy to top-up re-fillable e-cigarettes. This is one example of a chemical with no valid reason to be there. Globally, it’s <a href="https://pubchem.ncbi.nlm.nih.gov/compound/2-Chlorophenol#section=Hazard-Classes-and-Categories">classified</a> as “harmful if inhaled”. Its presence is likely due to contamination during manufacturing.</p>
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Read more:
<a href="https://theconversation.com/many-e-cigarette-vaping-liquids-contain-toxic-chemicals-new-australian-research-169615">Many e-cigarette vaping liquids contain toxic chemicals: new Australian research</a>
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<h2>How about polonium?</h2>
<p>One potential ingredient that has been in the news in recent weeks is radioactive polonium-210, the same substance used to <a href="https://theconversation.com/litvinenko-poisoning-polonium-explained-53514">assassinate</a> former Russian spy Alexander Litvinenko in 2006. The Queensland government is <a href="https://www.abc.net.au/news/2023-07-26/queensland-scientists-test-vapes-for-polonium-210/102564282">now testing</a> vapes for it.</p>
<p>Polonium-210 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9207432/">can be found</a> in traditional cigarettes and other tobacco products. That’s because tobacco plants <a href="https://www.science.org/doi/abs/10.1126/science.153.3738.880">absorb it</a> and other radioactive materials from the soil, air and high-phosphate fertiliser.</p>
<p>Whether polonium-210 is found in aerosols produced by e-cigarettes remains to be seen. Although it is feasible if the glycerine in e-liquids comes from plants and similar fertilisers are used to grow them.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1684030171287019522"}"></div></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/litvinenko-poisoning-polonium-explained-53514">Litvinenko poisoning: polonium explained</a>
</strong>
</em>
</p>
<hr>
<h2>It’s not just the ingredients</h2>
<p>Aside from their ingredients, the materials e-cigarette devices are made from can end up in our bodies.</p>
<p><a href="https://ehp.niehs.nih.gov/doi/full/10.1289/EHP2175">Toxic metals</a> and <a href="https://ehp.niehs.nih.gov/doi/full/10.1289/EHP5686">related substances</a> such as arsenic, lead, chromium and nickel can be detected in both e-liquids and vapers’ urine, saliva and blood.</p>
<p>These substances can pose serious health risks (such as being carcinogenic). They can leach from several parts of an e-cigarette, including the heating coil, wires and soldered joints.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&rect=1%2C0%2C997%2C655&q=45&auto=format&w=1000&fit=clip"><img alt="Colourful, disposable vapes on a blue background" src="https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&rect=1%2C0%2C997%2C655&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=394&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=394&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=394&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=495&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=495&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541152/original/file-20230804-21381-h5ifyj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=495&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chemicals from the device itself can end up in our blood, urine and saliva.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/set-colorful-disposable-electronic-cigarettes-on-2065547126">Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-asked-over-700-teens-where-they-bought-their-vapes-heres-what-they-said-190669">We asked over 700 teens where they bought their vapes. Here's what they said</a>
</strong>
</em>
</p>
<hr>
<h2>That’s not all</h2>
<p>The process of heating e-liquids to create an inhalable aerosol also changes their chemical make-up to produce <a href="https://pubs.acs.org/doi/10.1021/acs.chemrestox.9b00410">degradation</a> <a href="https://pubs.acs.org/doi/10.1021/acs.est.7b02205">products</a>. </p>
<p>These include:</p>
<ul>
<li><p>formaldehyde (a substance used to embalm dead bodies)</p></li>
<li><p>acetaldehyde (a key substance that contributes to a hangover after drinking alcohol)</p></li>
<li><p>acrolein (used as a chemical weapon in the first world war and now used as a herbicide).</p></li>
</ul>
<p>These chemicals are <a href="https://www.mdpi.com/2305-6304/10/12/714">often detected</a> in <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6129974">e-cigarette samples</a>. However due to different devices and how the samples are collected, the <a href="https://ehjournal.biomedcentral.com/articles/10.1186/s12940-017-0249-x">levels measured</a> <a href="https://pubs.acs.org/doi/10.1021/acs.est.7b02205">vary widely</a> between studies.</p>
<p>Often, the levels are very low, leading to proponents of vaping arguing e-cigarettes are far safer than tobacco smoking. </p>
<p>But this argument does not acknowledge that many e-cigarette users (particularly adolescents) <a href="https://www.tobaccoinaustralia.org.au/chapter-18-e-cigarettes/18-3-extent">were or are not cigarette smokers</a>, meaning a better comparison is between e-cigarette use and breathing “fresh” air. </p>
<p>An e-cigarette user is undoubtedly exposed to more toxins and harmful substances than a non-smoker. People who buy tobacco cigarettes are also confronted with a plethora of warnings about the hazards of smoking, while vapers generally are not.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/sex-and-lies-are-used-to-sell-vapes-online-even-we-were-surprised-at-the-marketing-tactics-we-found-200446">Sex and lies are used to sell vapes online. Even we were surprised at the marketing tactics we found</a>
</strong>
</em>
</p>
<hr>
<h2>How about labelling?</h2>
<p>This leads to another reason why it’s impossible to tell what is in vapes – the lack of information, including warnings, <a href="https://www.legislation.gov.au/Details/F2021L00595">on the label</a>.</p>
<p>Even if labels are present, they don’t always reflect what’s in the product. Nicotine concentration of e-liquids is often quite different to what is on the label, and “nicotine-free” e-liquids often <a href="https://journal.chestnet.org/article/S0012-3692(20)30134-3/fulltext">contain nicotine</a>.</p>
<p>Products are also labelled with generic flavour names such as “berry” or “tobacco”. But there is no way for a user to know what chemicals have been added to make those “berry” or “tobacco” flavours or the changes in these chemicals that may occur with heating and/or interacting with other ingredients and the device components. “Berry” <a href="https://tobaccocontrol.bmj.com/content/30/2/185">flavour</a> alone could be made from <a href="https://tobaccocontrol.bmj.com/content/tobaccocontrol/suppl/2020/02/10/tobaccocontrol-2019-055447.DC1/tobaccocontrol-2019-055447supp001_data_supplement.pdf">more than 35</a> different chemicals. </p>
<p>Flavouring chemicals may be “food grade” or classified as safe-to-eat. However mixing them into e-liquids, heating and inhaling them is a very different type of exposure, compared to eating them.</p>
<p>One example is benzaldehyde (an almond flavouring). When this is inhaled, it <a href="https://pubs.acs.org/doi/abs/10.1021/acs.chemrestox.9b00171">impairs</a> the <a href="https://www.sciencedirect.com/science/article/pii/S2214750023000380">immune function</a> of lung cells. This could potentially reduce a vaper’s ability to deal with other inhaled toxins, or respiratory infections. </p>
<p>Benzaldehyde is one of only <a href="https://www.legislation.gov.au/Details/F2021L00595">eight</a> banned e-liquid ingredients in Australia. The list is so short because we don’t have enough information on the health effects if inhaled of other flavouring chemicals, and their interactions with other e-liquid ingredients.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1670806592961355777"}"></div></p>
<h2>Where to next?</h2>
<p>For us to better assess the health risks of vapes, we need to learn more about:</p>
<ul>
<li><p>what happens when flavour chemicals are heated and inhaled</p></li>
<li><p>the interactions between different e-liquid ingredients</p></li>
<li><p>what other contaminants may be present in e-liquids</p></li>
<li><p>new, potentially harmful, substances in e-cigarettes.</p></li>
</ul>
<p>Finally, we need to know more about how people use e-cigarettes so we can better understand and quantify the health risks in the real world.</p><img src="https://counter.theconversation.com/content/210462/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexander Larcombe has previously received funding for e-cigarette research from the National Health and Medical Research Council, Lung Foundation Australia, Minderoo Foundation, Health Department of Western Australia and Asthma Foundation of Western Australia. The funders played no role in the conduct of the research. He is also a member of the Australian Council on Smoking and Health (ACOSH).</span></em></p>It’s not just the ingredients we should be concerned about. The devices themselves release chemicals that end up in our blood and urine.Alexander Larcombe, Associate Professor and Head of Respiratory Environmental Health, Telethon Kids InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2102782023-07-25T20:05:54Z2023-07-25T20:05:54ZA new TikTok trend has people drinking toxic borax. An expert explains the risks – and how to read product labels<figure><img src="https://images.theconversation.com/files/539195/original/file-20230725-21-kg8vuz.jpeg?ixlib=rb-1.1.0&rect=32%2C16%2C5456%2C3637&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>A potentially dangerous trend has <a href="https://www.nbcnews.com/health/health-news/drinking-borax-tiktok-trend-medical-authorities-debunk-rcna95526">gained prominence</a> on TikTok, with a number of people mixing borax into water and drinking it for supposed health benefits.</p>
<p>This isn’t new. Social media platforms have been host to many dangerous “challenges” – and users have been dosing themselves with questionable substances for years. </p>
<p>There’s no evidence to support the latest claims about borax. So how dangerous is it? And how can we assess the safety of the many other substances we use in daily life?</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=669&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=669&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=669&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=841&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=841&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539189/original/file-20230725-29-jcbua6.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=841&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">These borax-related topics have been trending on TikTok.</span>
<span class="attribution"><span class="source">Screenshot/TikTok</span></span>
</figcaption>
</figure>
<h2>What is borax?</h2>
<p>Borax, or sodium borate decahydrate, is a salt made of a combination of boron, sodium, oxygen and hydrogen. It comes in the form of a colourless crystalline solid that can easily be dissolved in water. </p>
<p><a href="https://www.foodauthority.nsw.gov.au/consumer/keeping-food-safe/other-topics/borax-and-boric-acid">Borax and the related boric acid</a> are commonly used in household products including laundry cleaning products, wood preservers, fertilisers, contact lens solution and ant killers.</p>
<p>Borax crystals are also widely available in supermarkets, hardware stores and garden centres. These products are typically pure borax, but other additives may be present.</p>
<h2>Don’t confuse borax with boron</h2>
<p>TikTok users posting videos of themselves ingesting borax and water solution <a href="https://www.nbcnews.com/health/health-news/drinking-borax-tiktok-trend-medical-authorities-debunk-rcna95526">have falsely</a> <a href="https://www.ndtv.com/world-news/people-are-consuming-borax-in-new-tiktok-trend-experts-call-it-dangerous-4238058">claimed</a> it can help treat inflammation, joint pain, arthritis, lupus and a range of other conditions. </p>
<p>This is yet another hoax “remedy” in a long list of false hope products. Alternative therapies are often touted as being “natural” and therefore supposedly non-toxic.</p>
<p>But while borax is <a href="https://www.healthline.com/health/is-borax-safe#safety">naturally occurring</a>, this isn’t a guarantee of safety. Arsenic, ricin and the toxin <a href="https://www.cdc.gov/botulism/general.html">responsible for botulism</a> are also 100% natural, but can be highly toxic to humans. </p>
<p>And although the element boron specifically is <a href="https://www.frontiersin.org/articles/10.3389/fpls.2020.610307/full">considered essential</a> for plants and some animals, its role in the functioning of the human body is less clear. Boron can be found in some of the foods we eat, such as grapes and potatoes, but isn’t classified as an <a href="https://apps.who.int/iris/handle/10665/37931">essential nutrient</a>. The very small amount of boron your body may need can be safely obtained by eating a <a href="https://ods.od.nih.gov/factsheets/Boron-HealthProfessional/">diet rich in fruits and vegetables</a>. </p>
<h2>How dangerous is borax?</h2>
<p>Borax is <em>not</em> considered safe to ingest. </p>
<p>In toxicology, the median lethal dose, or LD50, is the approximate dose required to kill half the animals in a population being studied.</p>
<p>The LD50 for borax in rats is about 5g per kilogram of body weight. This is a relatively large dose, which means acute toxicity causing death is unlikely in humans. But just because a dose won’t kill, that doesn’t mean it isn’t harmful – and it definitely doesn’t mean it’s good for you.</p>
<p>Borax was used extensively as a food preservative in the early 1900s. That was before the <a href="https://blog.history.in.gov/dr-harvey-wiley-and-his-poison-squad/">work of Harvey Washington Wiley</a> and his poison squad uncovered a range of side effects to consumption, including headaches, nausea, vomiting, gastric discomfort and more.</p>
<p>Borax is also classified as a <a href="https://www.industrialchemicals.gov.au/sites/default/files/Borax%20%28B4Na2O7.10H2O%29_Human%20health%20tier%20II%20assessment.pdf">reproductive toxin</a>, which means it “may impair fertility” and “may cause harm to the unborn child”. <a href="https://www.foodauthority.nsw.gov.au/consumer/keeping-food-safe/other-topics/borax-and-boric-acid">It is banned</a> as a food additive in Australia, the United States and several other countries.</p>
<h2>Safety first, last and always</h2>
<p>A number of dangerous social media challenges have gone viral over the past decade. One notable example was the “<a href="https://www.washingtonpost.com/news/to-your-health/wp/2018/01/13/teens-are-daring-each-other-to-eat-tide-pods-we-dont-need-to-tell-you-thats-a-bad-idea/">Tide pod challenge</a>”, in which users recorded themselves biting or eating laundry pods. </p>
<p>The consumption of laundry pods has <a href="https://www.consumerreports.org/laundry-cleaning/liquid-laundry-detergent-pods-pose-lethal-risk/">caused a number of deaths</a> (although these can’t necessarily be linked to the Tide pod challenge). From 2013 to 2022, poison centres in the US <a href="https://www.aapcc.org/track/laundry-detergent-packets">have managed around</a> 10,000 cases each year related to children age five and under being exposed to laundry detergent packets. </p>
<p>Clearly, we shouldn’t be drinking borax or eating laundry pods. Yet such substances can’t always be avoided – so the best protection is to understand the dangers associated with them. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/people-want-to-use-bleach-and-antiseptic-for-covid-and-are-calling-us-for-advice-168660">People want to use bleach and antiseptic for COVID and are calling us for advice</a>
</strong>
</em>
</p>
<hr>
<p>Apart from reading the generic safety warnings on a product, such as “CAUTION” or “KEEP OUT OF REACH OF CHILDREN”, consumers can dig a little deeper through the use of resources known as safety data sheets (or SDS). </p>
<p>Every product containing hazardous substances must legally have an SDS. So whether you’re using a shampoo, hand sanitiser, vinegar or borax, there will almost certainly be an SDS available. <a href="https://imgcdn.mckesson.com/CumulusWeb/Click_and_learn/SDS_JOHSPC_SHAMPOO_BABY_1_7_FL_OZ_144_CS.pdf">Here’s the SDS</a> for Johnson’s Baby Shampoo, as an example.</p>
<p>You can find the SDS of a product online by searching the product’s name and “SDS” in Google. These documents follow a standardised format and provide details of hazards associated with a product.</p>
<p>They also include <a href="https://www.safeworkaustralia.gov.au/safety-topic/hazards/chemicals/classifying-chemicals/using-ghs">standardised hazard pictograms</a> that represent the associated physical, health and environmental risks. You’ve probably seen these before, such as a “flammable” sign on a deodorant, or a “corrosive” sign on a household cleaner.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/539174/original/file-20230725-17-i858fz.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/539174/original/file-20230725-17-i858fz.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=776&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539174/original/file-20230725-17-i858fz.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=776&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539174/original/file-20230725-17-i858fz.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=776&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539174/original/file-20230725-17-i858fz.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=975&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539174/original/file-20230725-17-i858fz.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=975&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539174/original/file-20230725-17-i858fz.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=975&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The international GHS system consists of nine symbols that represent the hazards associated with a substance.</span>
</figcaption>
</figure>
<p>As far as borax is concerned, the main <a href="https://cdn.commercev3.net/cdn.teachersource.com/downloads/MSDS/Borax-SDS.pdf">product shown in the TikTok videos</a> has an SDS that lists the human silhouette and exclamation mark pictograms. These correspond to the listed hazards of skin irritation, serious eye irritation and potential damage to fertility or an unborn child. </p>
<p>A number of precautionary statements follows – with advice on appropriate personal protective equipment, and how to store and dispose of the product. </p>
<p>Further details go beyond the typical consumer information and include composition, first aid information, toxicological information and fire fighting methods. These are helpful for medical professionals treating patients and fire fighters dealing with chemical spills and fires. </p>
<p>Safety data sheets <a href="https://pubs.acs.org/doi/full/10.1021/acs.oprd.1c00427">aren’t perfect</a>, but they are a useful resource. So the next time you see an unusual “miracle cure” on social media, or there’s a chemical in your home you aren’t sure about, consider reading the SDS. </p>
<hr>
<p><em>If you have been exposed to a potentially harmful substance, call your local poison information centre or seek medical attention.</em></p><img src="https://counter.theconversation.com/content/210278/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathan Kilah does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>How dangerous is borax? And what’s the best way to judge the toxicity of everyday household products?Nathan Kilah, Senior Lecturer in Chemistry, University of TasmaniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2093292023-07-10T20:09:55Z2023-07-10T20:09:55ZThe furry puss caterpillar’s venom packs a painful punch. Now new research shows it came from an unlikely source<figure><img src="https://images.theconversation.com/files/536469/original/file-20230710-25-6ofe7i.jpeg?ixlib=rb-1.1.0&rect=98%2C98%2C6491%2C4989&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Donald W. Hall</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Did you know venom – a toxic substance injected by one animal into another – has evolved around 100 times? </p>
<p>In our laboratory at the University of Queensland, my colleagues and I study all kinds of venomous animals. One reason we do this is to find new molecules that can be <a href="https://www.nature.com/articles/d42473-018-00315-6">used in medicines</a>, or as <a href="https://imb.uq.edu.au/article/2018/07/spider-venom-human-friendly-insecticides">bio-friendly insecticides</a>.</p>
<p>Scientists have used venom toxins from snakes, spiders and scorpions in various medical contexts, including to <a href="https://en.wikipedia.org/wiki/Captopril">lower blood pressure</a>, protect <a href="https://stories.uq.edu.au/imb/2020/venom/stroke/index.html">against stroke</a>, and <a href="https://en.wikipedia.org/wiki/Chlorotoxin">label tumours during surgery</a>.</p>
<p>There are several other groups of venomous animals, such as <a href="https://www.uq.edu.au/news/article/2018/02/assassin%E2%80%99s-venom-system-packs-deadly-double">assassin bugs</a> and <a href="https://www.mdpi.com/2072-6651/10/11/456">robber flies</a>, which have been largely neglected – yet their venom may prove to be just as useful to humans.</p>
<p>In research <a href="https://doi.org/10.1073/pnas.2305871120">published today</a> in the Proceedings of the National Academy of Sciences, our team investigated the venom from a group of caterpillars called asp caterpillars, which are notorious for their ability to cause excruciating pain. They’re also called puss caterpillars since they sport long, soft hairs that have been dubbed “toxic <a href="https://www.nationalgeographic.com/animals/article/toupee-caterpillar-venomous-animal-weird-insect">toupées</a>”.</p>
<p>We were surprised to find the main painful toxins in asp caterpillars belong to a family of molecules usually found in disease-causing bacteria. We discovered that a gene that codes for this kind of toxin hopped from bacteria to the ancestors of moths and butterflies millions of years ago, in a phenomenon called <a href="https://www.britannica.com/science/horizontal-gene-transfer">horizontal gene transfer</a>.</p>
<h2>Float like a butterfly, sting like a bee</h2>
<p>The insect group <a href="https://www.ento.csiro.au/education/insects/lepidoptera.html">Lepidoptera</a>, which we usually think of as butterflies and moths, are my favourite venomous animals. Interestingly, it’s always the larval forms (caterpillars) that are armed with venom, and not the adults. We think this is because caterpillars are particularly helpless against predators, and therefore need special defences. </p>
<p>This is also why venom has evolved multiple times just within Lepidoptera. Unlike most <a href="https://www.britannica.com/animal/arthropod">arthropods</a>, which use venom for hunting, caterpillars are among a select few (including bees) that use it purely to defend themselves from predators.</p>
<p>However, the venom of some of these caterpillar groups, including asp caterpillars, has never been examined with modern methods.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=421&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=421&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=421&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=530&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=530&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536436/original/file-20230710-31-mrdrxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=530&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">When touched, the tips of the smooth cylindrical venom spines break, injecting venom.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Evolution by horizontal gene transfer</h2>
<p>People who have been stung by asp caterpillars <a href="https://www.researchgate.net/figure/A-C-The-Asp-Caterpillar-Megalopyge-opercularis-can-vary-in-color-from-white-to-gray_fig1_5508450">have described</a> the feeling as being similar to “touching burning coals” or “being hit with a baseball bat”. We set out to find what this venom contains and how it can inflict such incredible pain.</p>
<p>Asp caterpillars aren’t found in Australia, so I had to travel to Florida to collect them from oak and elm trees. Although I couldn’t return with live individuals (due to the threat of invasive species), with the help of some US researchers I was able to bring some venom and preserved caterpillars back to the lab for analysis.</p>
<p>We used a variety of imaging and molecular techniques to build a picture of where the venom is made, what kinds of toxins it contains, and how those toxins produce pain. </p>
<p>Surprisingly, when we looked at the structures of the main pain-causing toxins, we found they belonged to a toxin group usually produced by bacteria, including disease-causing bacteria such as <em>E. coli</em> and salmonella. These caterpillar toxins work by punching holes in cells – the same mechanism the bacterial toxins use to inflict damage on humans. </p>
<p>When we analysed the family tree of the toxins in detail, we found a gene that codes for this kind of toxin had “hopped” from a bacterium to the ancestors of butterflies and moths hundreds of millions of years ago.</p>
<p>These hopping events are called horizontal gene transfer to distinguish them from the vertical transfer of genes from parents to offspring. These events are very rare. </p>
<p>In the case of asp caterpillars, DNA from the infecting bacteria would have not only had to come into contact with the ancestral caterpillar, but also get incorporated into its DNA, inside the cells that would become sperm or eggs (and be passed on to subsequent generations). </p>
<p>We know of only a few examples of the horizontal gene transfer of venom toxins.</p>
<h2>Harnessing nature’s resources</h2>
<p>Our study shows evolution and life are weirder and more complex than we usually assume. Beyond this, projects like this can also help us discover new ways in which venom toxins may benefit humans and the environment.</p>
<p>For example, toxins that make holes in cell membranes are already being investigated for their ability to <a href="https://www.nature.com/articles/s41467-019-13253-8">deliver lifesaving drugs</a> to the inside of cells.</p>
<p>Another potential application is in engineering toxins that could punch holes in cells to <a href="https://www.mdpi.com/2072-6651/15/4/297">selectively kill cancer cells</a>, while leaving normal cells intact. Our ability to develop such new technologies depends on discovering and understanding the molecular resources that exist in nature.</p>
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<strong>
Read more:
<a href="https://theconversation.com/ever-wondered-whod-win-in-a-fight-between-a-scorpion-and-tarantula-a-venom-scientist-explains-155138">Ever wondered who'd win in a fight between a scorpion and tarantula? A venom scientist explains</a>
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<img src="https://counter.theconversation.com/content/209329/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This work was funded through the Australian Research Council through Discovery Project DP200102867.</span></em></p>This caterpillar can cause excruciating pain when touched. But unlike most venomous arthropods, it uses its venom purely for self-defence.Andrew Walker, Postdoctoral Research Fellow, Institute for Molecular Bioscience, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2013812023-04-05T20:02:53Z2023-04-05T20:02:53ZPicking mushrooms can go horribly wrong. Here’s what can happen, according to a toxicologist<figure><img src="https://images.theconversation.com/files/516885/original/file-20230322-20-6dyr8m.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C998%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/picking-wild-mushrooms-autumn-forest-hand-1810787860">Shutterstock</a></span></figcaption></figure><p>It’s <a href="https://www.foodsafety.asn.au/topic/warning-not-to-pick-or-eat-wild-mushrooms-because-of-deadly-deathcap-mushroom-risk-7-march-2023/">mushroom season</a> in many parts of Australia. Between now and about June, the cooler and wetter weather are the perfect conditions for mushrooms to grow in the wild. In Tasmania and parts of Victoria, mushrooms can grow all year round.</p>
<p>At the New South Wales Poisons Information Centre, where I’m the medical director, we receive 300–500 calls a year about mushrooms. Most are from people concerned about what they or others have eaten. Others are from health workers seeking advice on how to treat poisonings.</p>
<p>Here’s what happens if you eat a toxic mushroom, and if you do, what really helps health workers know what to do next.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-ancient-intimate-relationship-between-trees-and-fungi-from-fairy-toadstools-to-technicolour-mushrooms-165974">The ancient, intimate relationship between trees and fungi, from fairy toadstools to technicolour mushrooms</a>
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</em>
</p>
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<h2>A rich history … but can make you sick</h2>
<p>Mushroom foraging, or mushroom hunting, is popular in <a href="https://pubmed.ncbi.nlm.nih.gov/23704957/">many parts of the world</a>. It’s associated with <a href="https://www.tandfonline.com/doi/full/10.1080/26395916.2022.2055148">local cultures</a>, a social activity with family and friends, or to find food. So mushroom foraging can have deep emotional or cultural connections.</p>
<p>The success of a foraging expedition depends on finding mushrooms, and being able to differentiate the edible from the toxic varieties. That’s not always easy and even experienced foragers can make mistakes.</p>
<p>Toxic mushrooms can resemble edible ones, and might look different according to where they grow, including across continents. Mushroom identification apps do not appear to be <a href="https://pubmed.ncbi.nlm.nih.gov/36794335/">accurate enough</a> in Australia. It’s also not clear how useful mushroom-identification books are at helping people distinguish the edible from the toxic.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-glowing-ghost-mushroom-looks-like-it-comes-from-a-fungal-netherworld-111607">The glowing ghost mushroom looks like it comes from a fungal netherworld</a>
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<h2>Different types of mushroom pickers</h2>
<p>People can be at risk of mushroom poisoning for different reasons. </p>
<p><strong>1. Young, and sometimes older people</strong></p>
<p>A common group of those at risk is younger people (mostly toddlers, as they explore the world around them), and sometimes older people (mostly people with cognitive issues, such as dementia). These people tend to find and eat mushrooms outside when partially supervised. </p>
<p>This group tends to eat smaller amounts, which is usually low risk, and contact poisons information centres early. But assessing the toxicity of the mushrooms they have eaten can be hard if the only information we have is chewed mushroom remnants from an uncertain source.</p>
<p><strong>2. Foragers</strong></p>
<p>The other at-risk category are people who eat larger amounts of mushrooms, usually as part of a foraging group, and develop symptoms. These people contact the poisons information centre some time after eating the mushrooms.</p>
<p>Uncooked mushroom samples are often not available. And we don’t always know if their symptoms relate to mushrooms or something else.</p>
<p>Most mushroom poisonings are mild. But sometimes this group develops severe poisoning that requires medical attention, including hospital admission, including those foraging for <a href="https://pubmed.ncbi.nlm.nih.gov/23330770/">food</a> or <a href="https://pubmed.ncbi.nlm.nih.gov/11951934/">hallucingenic mushrooms</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/toxic-poppy-seeds-are-sending-people-to-hospital-3-experts-explain-whats-behind-the-latest-food-scare-194716">Toxic poppy seeds are sending people to hospital. 3 experts explain what's behind the latest food scare</a>
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</em>
</p>
<hr>
<h2>What happens in the body?</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Agaricus xanthodermus or yellow stainer mushroom" src="https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517077/original/file-20230322-24-smm40f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The yellow stainer can cause nausea, vomiting, stomach pain and diarrhoea.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/agaricus-xanthodermus-yellowstaining-mushroom-july-belarus-1465659980">Shutterstock</a></span>
</figcaption>
</figure>
<p>The most common symptoms are nausea, vomiting, stomach pain and diarrhoea. We don’t always know how mushrooms cause these effects. But this is probably due to chemicals that directly irritate or kill cells in the gut. </p>
<p>We expect these symptoms after eating mushrooms such as the yellow stainer or <em><a href="https://www.rbg.vic.gov.au/science/herbarium/yellow-staining-mushroom/">Agaricus xanthodermus</a></em>, found in many parts of Australia, and the green-spored parasol or <em><a href="https://www.childrens.health.qld.gov.au/poisonous-plant-green-spored-parasol-chlorophyllum-molybdites/">Chlorophyllum molybdites</a></em>, found mostly in tropical and subtropical regions.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Chlorophyllum molybdites or green-spored parasol" src="https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=355&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=355&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=355&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=446&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=446&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517079/original/file-20230322-20-vqjx7h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=446&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The green-spored parasol can also cause gut symptoms.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/poisonous-mushrooms-chlorophyllum-molybditeswhite-flowers-blooming-1792021862">Shutterstock</a></span>
</figcaption>
</figure>
<p>The mushroom that features in the Smurfs, <em><a href="https://www.dpaw.wa.gov.au/images/documents/about/science/fungus/61_2012-05_Amanita_muscaria_DEC_FF.pdf">Amanita muscaria</a></em>, can cause gut symptoms. It can <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7977045/">also cause</a> sedation (which may be severe) and fatigue, or agitation, confusion and changes in perception. This is because it contains chemicals such as ibotenic acid and muscimol that can stimulate or inhibit different parts of the brain. This mushroom is found in subtropical and temporal climates in Australia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Fly agaric or Amanita muscaria" src="https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517080/original/file-20230322-20-w936wx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The mushroom <em>Amanita muscaria</em> can sedate you.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fly-agaric-amanita-muscaria-basidiomycete-genus-1910285572">Shutterstock</a></span>
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<p>Toxic effects from other mushrooms includes sleepiness, lethargy, seizures, low blood pressure, hallucinations and agitation. <a href="https://www.jcu.edu.au/discover-nature-at-jcu/fungi/fungi-by-scientific-name/coprinus-atramentarius#:%7E:text=Description,liquid%20hence%20the%20common%20name">Some mushrooms</a> can interact with alcohol for a couple of days after eating the mushroom, causing flushing, nausea, vomiting and low blood pressure. </p>
<p>Fortunately, people usually recover from these types of symptoms as their body naturally eliminates the toxins.</p>
<p>But Australia also has poisonous mushrooms that <a href="https://pubmed.ncbi.nlm.nih.gov/23330770/">can kill</a>, or cause permanent <a href="https://pubmed.ncbi.nlm.nih.gov/33605821/">liver</a> or <a href="https://anzsnasm.com/10752">kidney failure</a>. That’s because they contain toxins that kill liver, kidney and other cells in essential organs of the body that the body cannot repair.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Amanita phalloides or death cap mushroom" src="https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517081/original/file-20230322-16-c76ppm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Eating a death cap mushroom can cause liver failure or can kill.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/amanita-phalloides-commonly-known-death-cap-2204034039">Shutterstock</a></span>
</figcaption>
</figure>
<p>An example is the death cap mushroom (<em><a href="https://pubmed.ncbi.nlm.nih.gov/23330770/">Amanita phalloides</a></em>), which is found in Tasmania, Victoria, South Australia and the Australian Capital Territory.</p>
<p>In Tasmania, <em>Cortinarius eartoxicus</em> causes <a href="https://anzsnasm.com/10752">kidney failure</a> requiring dialysis. Similar varieties may also be <a href="https://pubmed.ncbi.nlm.nih.gov/11951934/">in Victoria</a> but have yet to be formally identified.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/whats-in-your-porcini-packet-you-may-find-a-new-species-or-three-31740">What's in your porcini packet? You may find a new species ... or three</a>
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</em>
</p>
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<h2>What can you tell the person treating you?</h2>
<p>Knowing which mushroom people have eaten helps us predict the likely course of events and to choose the best treatment. </p>
<p>But people who call us for advice rarely have fresh samples or photos to allow us to identify the mushroom. People may also eat several different varieties of mushrooms at once, which can complicate how we assess you. </p>
<p>Our knowledge about poisonous mushrooms growing in Australia is also incomplete. In some cases, we rely on information reported from overseas but we are not certain how this applies to Australia, or to the region where the consumed mushroom was picked.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-peculiar-history-of-thornapple-the-hallucinogenic-weed-that-ended-up-in-supermarket-spinach-197014">The peculiar history of thornapple, the hallucinogenic weed that ended up in supermarket spinach</a>
</strong>
</em>
</p>
<hr>
<h2>What should I do if I’m worried?</h2>
<p>If you think you’ve eaten a toxic wild mushroom, contact a poisons information centre as soon as possible (details below). Health staff can provide advice related to your exposure, including the location of the exposure, amount eaten and your symptoms. </p>
<p>Some people may be advised to watch and wait at home, but others will need to go to hospital immediately. This allows treatments that may reduce the amount absorbed and the severity of poisoning.</p>
<h2>We can prevent this</h2>
<p>The safest way of obtaining mushrooms is from a reputable supermarket, grocer or market. </p>
<p>But if you choose to forage for wild mushrooms, then as a minimum, get advice from a relevant book or an experienced person, keep a sample of the mushroom and take lots of photos. Photos should include where they grow, and different angles of the mushroom. This includes the top, stem, underside and base (underground) portions. This may help us identify the mushroom if you or someone else develops symptoms.</p>
<hr>
<p><em>If this article raises health concerns for you or for someone you know about consuming mushrooms, call the <a href="https://www.poisonsinfo.nsw.gov.au">Poisons Information Centre</a> from anywhere in Australia on 131 126. This evidence-base advice is available 24 hours a day. For life-threatening symptoms, call 000.</em></p><img src="https://counter.theconversation.com/content/201381/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Darren Roberts is the Medical Director of the NSW Poisons Information Centre</span></em></p>It’s mushroom season in many parts of Australia. Here’s what you need to know before you go foraging.Darren Roberts, Conjoint Associate Professor in clinical pharmacology and toxicology, St Vincent’s Healthcare Clinical Campus, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1994822023-03-28T12:15:09Z2023-03-28T12:15:09ZWhat is xylazine? A medical toxicologist explains how it increases overdose risk, and why Narcan can still save a life<figure><img src="https://images.theconversation.com/files/517430/original/file-20230324-20-vu2ybd.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5444%2C3627&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Although xylazine is not an opioid, naloxone can reverse the effects of the fentanyl and heroin it is often mixed with.</span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/PhotoEssayFentanylsScourge/6b522b7eb85b4bf3aca36ae6cb30ed2a">AP Photo/Jae C. Hong</a></span></figcaption></figure><p>The White House officially designated fentanyl adulterated with xylazine as an <a href="https://www.whitehouse.gov/ondcp/briefing-room/2023/04/12/biden-harris-administration-designates-fentanyl-combined-with-xylazine-as-an-emerging-threat-to-the-united-states/">emerging threat to the U.S.</a> on Apr. 12, 2023. Earlier, the U.S. Drug Enforcement Administration <a href="https://www.dea.gov/alert/dea-reports-widespread-threat-fentanyl-mixed-xylazine">issued a warning</a> on Mar. 21, 2023, about an increase in trafficking of fentanyl adulterated with xylazine, which can increase the risk of overdosing on an <a href="https://theconversation.com/what-is-fentanyl-and-why-is-it-behind-the-deadly-surge-in-us-drug-overdoses-a-medical-toxicologist-explains-182629">already deadly drug</a>. Xylazine is <a href="https://doi.org/10.1016/j.drugalcdep.2022.109380">increasingly appearing</a> within the U.S. supply of illicit opioids like fentanyl and heroin. The agency noted that it has seized mixtures of xylazine and fentanyl in 48 of 50 states.</p>
<p>Xylazine, commonly referred to as <a href="https://khn.org/news/article/xylazine-tranq-drugs-dangerous/">tranq</a>, is a <a href="https://www.drugsandalcohol.ie/13119/">drug adulterant</a> – a substance intentionally added to a drug product to <a href="https://theconversation.com/rat-poison-is-just-one-of-the-potentially-dangerous-substances-likely-to-be-mixed-into-illicit-drugs-163568">enhance its effects</a>. Illicit drugmakers may include xylazine to <a href="https://doi.org/10.1016/j.drugalcdep.2022.109380">prolong opioid highs</a> or prevent withdrawal symptoms. </p>
<p>As a <a href="https://scholar.google.com/citations?user=X55PT8EAAAAJ&hl=en">physician who cares for people who use fentanyl</a>, I worry about the ways xylazine increases their risk for overdose. I worry even more that misunderstandings about xylazine can make bystanders less likely to <a href="https://umasstox.com/narcan/">administer the lifesaving drug naloxone (Narcan)</a> during an overdose. If you suspect an overdose, calling emergency medical services and administering naloxone are still the critical first steps to saving a life.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/HzAvzNoUERE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Learning what to do when someone overdoses can help save a life.</span></figcaption>
</figure>
<h2>Tranq overdoses and fentanyl</h2>
<p>Xylazine was originally developed as a veterinary anesthesia. It was first identified as an adulterant in heroin supplies <a href="https://doi.org/10.1186/1747-597X-6-7">in the early 2000s</a>. Although xylazine is not an opioid, it induces opioidlike effects, including sedation, slowed heart rate and small pupils, similar to the effects produced in people by its pharmaceutical cousin clonidine. Xylazine use is also associated with <a href="https://doi.org/10.1007%2Fs11524-011-9662-6">serious skin and soft tissue ulcers and infections</a>.</p>
<p>The use of opioids with sedating medications like xylazine increases the risk of fatal overdose. Historically, people who use drugs <a href="https://doi.org/10.1007%2Fs11524-011-9662-6">have been unaware</a> that xylazine is in the drug supply and are <a href="https://theconversation.com/rat-poison-is-just-one-of-the-potentially-dangerous-substances-likely-to-be-mixed-into-illicit-drugs-163568">unable to tell</a> whether they have been exposed to it. Routine hospital drug testing does not detect xylazine, further complicating surveillance.</p>
<p>Xylazine overdoses rarely occur in isolation. Xylazine detection in heroin- and fentanyl-associated deaths in Philadelphia has grown from less than 2% before 2015 to <a href="http://dx.doi.org/10.1136/injuryprev-2020-043968">more than 31% in 2019</a>. Similarly, one study of 210 xylazine-associated deaths in Chicago from 2017 to 2021 found that fentanyl or a chemically similar substance was detected in <a href="http://dx.doi.org/10.15585/mmwr.mm7113a3">99.1% of overdoses</a>. This data underscores the key role that fentanyl plays in causing fatal overdoses in cases where xylazine is found, and anecdotal evidence suggests the problem is only increasing.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of hands holding pieces of fentanyl" src="https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/517435/original/file-20230324-1164-oqro8m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Xylazine overdoses often occur in the presence of fentanyl or heroin.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/PhotoEssayFentanylsScourge/4e185189ef7e4b35b1c5fad7d66c75d9">AP Photo/Jae C. Hong</a></span>
</figcaption>
</figure>
<h2>Naloxone and xylazine</h2>
<p>Unfortunately, increasing awareness of xylazine has contributed to the myth of <a href="https://www.changingthenarrative.news/naloxone-resistant-fentanyl">“naloxone-resistant” overdoses</a>. Unlike overdoses with opioids only, patients experiencing xylazine-associated overdoses may not immediately wake up after naloxone administration. While naloxone may not reverse the effects of xylazine, it is still able to reverse the effects of the fentanyl it is often mixed with and should be used in all suspected opioid overdoses. </p>
<p>The critical goal of administering naloxone is to prevent patients from dying of dangerously low breathing rates. Bystanders who suspect an overdose <a href="https://www.youtube.com/watch?v=HzAvzNoUERE">should always call 911</a> to bring in experts in case treatment is required.</p>
<p><em>Article updated to include a White House announcement on Apr. 12, 2023</em></p><img src="https://counter.theconversation.com/content/199482/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kavita Babu receives funding from the National Institute on Drug Abuse, the MA Department of Public Health/ Bureau of Substance Addiction Services, the Centers for Disease Control and Prevention, and the National Highway Traffic Safety Administration. All opinions here are hers and do not represent the position of these organizations. </span></em></p>Xylazine, or tranq, is increasingly being mixed with drugs like fentanyl or heroin and can be difficult to detect. Most people who use drugs are unable to tell if they have been exposed to it.Kavita Babu, Professor of Emergency Medicine, UMass Chan Medical SchoolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1989942023-03-27T23:01:02Z2023-03-27T23:01:02ZWhat is a paraben and why are so many products advertised as ‘paraben-free’?<figure><img src="https://images.theconversation.com/files/510738/original/file-20230216-26-hxjirz.jpg?ixlib=rb-1.1.0&rect=5%2C5%2C3489%2C2205&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>You might have noticed many skin and haircare products are advertised as “paraben-free”, or come across online influencers warning parabens are terrible for your health.</p>
<p>But what is a paraben? And could a minor ingredient in products that many of us use daily really be that bad for us? </p>
<p>Let’s take a closer look.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-does-exposure-to-environmental-chemicals-mean-for-our-health-41876">What does exposure to environmental chemicals mean for our health?</a>
</strong>
</em>
</p>
<hr>
<h2>What are parabens?</h2>
<p>Chemically speaking, paraben is the collective name for a group of closely related compounds – the parahydroxybenzoates. The “para” refers to the positions of certain parts of the molecule (it’s also where the “para” in “paracetamol” comes from). </p>
<p>There are several different types of paraben, so you might see methylparaben, ethylparaben propylparaben, or butylparaben, in a product’s ingredient list. They may also be listed as a more formal chemical name. Methylparaben can be listed as 4-hydroxy methyl ester benzoic acid or methyl 4-hydroxybenzoate for example.</p>
<figure class="align-center ">
<img alt="a cartoon style drawing of Methylparaben" src="https://images.theconversation.com/files/509744/original/file-20230213-18-9qon73.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/509744/original/file-20230213-18-9qon73.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/509744/original/file-20230213-18-9qon73.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/509744/original/file-20230213-18-9qon73.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/509744/original/file-20230213-18-9qon73.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/509744/original/file-20230213-18-9qon73.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/509744/original/file-20230213-18-9qon73.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Methylparaben, commonly used as a preservative in skincare and cosmetics.</span>
<span class="attribution"><span class="source">Oliver Jones via the Molecular-Icons Generator app</span></span>
</figcaption>
</figure>
<p>The shorter version is that parabens are a group of related molecules added in small amounts (less than 1%, usually lower) to food, drugs and cosmetics as preservatives.</p>
<p>They work by preventing the growth of harmful bacteria and fungi to improve product shelf life and safety. More than one paraben may be used, and they may be combined with other preservatives to protect against a broad range of microorganisms.</p>
<p>Parabens can be absorbed through the skin or ingested but are generally excreted quickly, usually via <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1764178/">urine</a>. They have been in use for decades and no parabens have been banned in <a href="https://www.choice.com.au/health-and-body/beauty-and-personal-care/skin-care-and-cosmetics/articles/chemicals-in-cosmetics">Australia</a>.</p>
<p><a href="https://www.industrialchemicals.gov.au/sites/default/files/Parabens_Human%20health%20tier%20II%20assessment.pdf">Some studies</a> on cell cultures or animals have suggested parabens can affect the endocrine system (which controls our hormones) but it’s not clear how or even <a href="https://pubmed.ncbi.nlm.nih.gov/16097138/">if this is relevant to humans</a>. </p>
<p>The amounts used in some of those animal studies are much, much higher than you would find in make-up, for example. A lot of these <a href="https://journals.sagepub.com/doi/10.1177/109158180802704s01">studies</a> also involved feeding the chemicals to the animals or injecting them, rather than putting them on the skin (which results in much lower absorption into the body).</p>
<p>You might also have heard parabens are “oestrogenic” (meaning they can mimic or affect oestrogen in the body). In fact, parabens are <a href="https://journals.sagepub.com/doi/10.1177/109158180802704s01">far less oestrogenic</a> than natural oestrogen (that both males and females produce). They are also less oestrogenic than <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4153304/">phytoestrogens</a>, compounds produced naturally by many plants.</p>
<p>So, even though there have been studies raising concern, the overall risk in humans using parabens in normal doses is low. As the Australian Industrial Chemicals Introduction Scheme <a href="https://www.industrialchemicals.gov.au/sites/default/files/Parabens_Human%20health%20tier%20II%20assessment.pdf">puts</a> it:</p>
<blockquote>
<p>The available data do not indicate any risks associated with exposure to the chemicals in this group. The chemicals have been shown to have weak oestrogenic activity, but there are no established adverse outcome pathways for this effect.</p>
</blockquote>
<p>The US Food and Drug Administration reached a similar conclusion, <a href="https://www.fda.gov/cosmetics/resources-consumers-cosmetics/cosmetics-safety-qa-parabens">noting</a></p>
<blockquote>
<p>Studies have shown, however, that parabens have significantly less oestrogenic activity than the body’s naturally occurring oestrogen. Parabens have not been shown to be harmful as used in cosmetics, where they are present only in very small amounts.</p>
</blockquote>
<h2>Isn’t natural better? Aren’t human-made chemicals bad for you?</h2>
<p>Whether something is natural or not tells you nothing about its safety. </p>
<p>Snake venom is natural, as is uranium, lead and mercury. I wouldn’t buy personal care products with these “natural” ingredients in them. </p>
<p>Many things we use every day without a second thought – like aspirin, nylon, and silicone cookware – are synthetic. </p>
<p>The name of a chemical also tells you nothing about risk. If I told you a substance contained ethyl butanoate, pentyl acetate, ethene and capric acid, would you eat it? Well, you probably already have; these are all found in <a href="https://jameskennedymonash.wordpress.com/2013/12/12/ingredients-of-an-all-natural-banana/">bananas</a> and many other fruits.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A woman looks critically at skincare and shampoo bottles." src="https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514585/original/file-20230310-147-oahdj7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Whether or not an ingredient is natural tells you nothing about its safety.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>So why are people worried about parabens, then?</h2>
<p>This goes back to an often misinterpreted 2004 study that found parabens in <a href="https://pubmed.ncbi.nlm.nih.gov/14745841/">breast tissue and breast cancers</a>. But this doesn’t mean much by itself and doesn’t justify claims parabens cause cancer. </p>
<p>Correlation is not causation. The presence of parabens in a tumour does not mean parabens <em>caused</em> the tumour. </p>
<p>In fact, the researchers in the 2004 study only looked at breast cancer tissue (and didn’t compare it with healthy tissue). They even found parabens in their blank samples (with no tissue in them at all). So, as others have <a href="https://www.youtube.com/watch?v=2DVcs9kP97s">noted</a>, it’s hard to draw any real conclusion from it about the role parabens may or may not play in cancer risk. </p>
<p>A lot of the endocrine disruptor stuff you hear on social media about parabens is usually from someone trying to spruik a “natural” or “clean” alternative, so you might not be seeing the full picture.</p>
<p>And remember: the presence of something does not automatically mean it is harmful. Toxicology 101 is “the dose makes the poison”. Everything is toxic in the right amount, even water. We should not ask whether a chemical causes cancer or acts as an endocrine disruptor, but whether it does so at the levels to which we are exposed.</p>
<p>The scientific consensus from the <a href="https://www.fda.gov/cosmetics/resources-consumers-cosmetics/cosmetics-safety-qa-parabens">US Food and Drug Administration</a>, the <a href="https://www.industrialchemicals.gov.au/sites/default/files/Parabens_Human%20health%20tier%20II%20assessment.pdf">Australian Industrial Chemicals Introduction Scheme</a> and the <a href="https://www.ema.europa.eu/en/documents/scientific-guideline/reflection-paper-use-methyl-propylparaben-excipients-human-medicinal-products-oral-use_en.pdf">European Medicines Agency</a> and others is that for parabens at normal dosages, the health risk is very low.</p>
<h2>So why are so many products marketed as ‘paraben-free’?</h2>
<p>Going “paraben-free” has become a very effective marketing tool. If people want paraben-free products and will pay more for them, why not give them paraben-free products? </p>
<p>But paraben-free does not mean preservative-free, nor does it mean the products are safer (even if that’s what is implied). </p>
<p>If you remove parabens from a product, you need to add other preservatives, which may be less effective. This increases the risk of the product going off (some users of “clean” make-up brands have reported finding mould in products) and could even cause harm. </p>
<h2>So what’s the verdict?</h2>
<p>Ultimately, the choice to use products containing parabens is a personal one. </p>
<p>As a chemist I think parabens are well-researched, safe and and necessary, but if you are worried, you can opt for paraben-free products. Just be aware they will probably have a shorter shelf life, contain other (less effective) preservatives, and could well have other problems. I’d take a small amount of a well studied, and <a href="https://www.industrialchemicals.gov.au/cosmetics-and-soap/personal-care-skincare-make-and-other-cosmetic-products">well-regulated</a>, chemical in my skincare products over mould any day.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-is-makeup-bad-for-your-skin-82820">Health Check: is makeup bad for your skin?</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/198994/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Oliver A.H. Jones does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Remember: the presence of something does not automatically mean it is harmful. It is the dose that makes the poison.Oliver A.H. Jones, Professor, RMIT UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1992512023-03-21T12:42:41Z2023-03-21T12:42:41ZPoisons are a potent tool for murder in fiction – a toxicologist explains how some dangerous chemicals kill<figure><img src="https://images.theconversation.com/files/515276/original/file-20230314-2595-90gnm9.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2121%2C1412&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Poisons are often not so clearly labeled.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/poison-bottle-with-a-skull-royalty-free-image/1319519485">Josefe Photography/iStock via Getty Images Plus</a></span></figcaption></figure><p>People have used poisons <a href="https://accesspharmacy.mhmedical.com/content.aspx?bookid=2462&sectionid=194918294">throughout history</a> for a variety of purposes: to hunt animals for food, to <a href="https://theconversation.com/poison-or-cure-traditional-chinese-medicine-shows-that-context-can-make-all-the-difference-163337">treat diseases</a> and to achieve nefarious ends like murder and assassination.</p>
<p>But what is a poison? Do all poisons act in the same way? Does the amount of the poison matter in terms of its toxicity?</p>
<p><a href="https://www.engr.colostate.edu/cbe/people/brad-reisfeld/">I am a toxicologist</a> who studies how chemicals affect human health, particularly when they cause harmful effects. As a fan of mystery and detective stories, which often feature the use of poisons, I’ve noticed a few poisons that turn up repeatedly in books, television and movies. How they really work is as fascinating as how they’re deployed toward evil ends in fiction.</p>
<h2>What is a poison?</h2>
<p>The 16th-century <a href="https://pubmed.ncbi.nlm.nih.gov/27214290/">physician–alchemist Paracelsus</a>, considered to be the father of toxicology, once wrote: “What is there that is not poison? All things are poison and nothing is without poison. Solely the dose determines that a thing is not a poison.” By this adage, any substance can be a poison with the appropriate amount.</p>
<p>Many people intentionally expose themselves to chemicals like ethanol through alcoholic beverages, nicotine through tobacco products and botulinum toxin through botox treatments at relatively low doses and suffer minimal adverse effects. However, at <a href="https://accesspharmacy.mhmedical.com/content.aspx?bookid=2462&sectionid=194918464">sufficiently high doses</a>, these chemicals can be lethal. The body’s response often depends on how the chemical interacts with receptors within or on the surface of cells, or how it binds to enzymes used for biological processes. Frequently, higher concentrations of the substance <a href="https://doi.org/10.1016/j.tox.2013.04.007">lead to stronger responses</a>.</p>
<p>Despite Paracelsus’ dictum, in popular culture the term “poison” is often reserved for chemical compounds that are not normally encountered in daily life and can lead to detrimental health effects even in relatively small amounts.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Person dispensing white pills from a bottle into hand." src="https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/515278/original/file-20230314-3245-vk99ad.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">At a high enough dose, any chemical could be poisonous.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/young-man-spilling-multiple-pills-in-his-hand-royalty-free-image/1432823897">Malorny/Moment via Getty Images</a></span>
</figcaption>
</figure>
<h2>Poisons in books, TV and film</h2>
<p>Novel writers and television and movie screenwriters have exploited numerous poisons in their works, including those that are chemical elements, such as <a href="https://web.archive.org/web/20090422045609/http://www.agathachristie.com/story-explorer/stories/450-from-paddington/">arsenic</a> and <a href="https://www.imdb.com/title/tt7737528/">polonium</a>, and those derived from animals, such as <a href="https://www.mrsherlockholmes.com/adventures/the-speckled-band/">snake venom</a> and <a href="https://columbophile.com/2019/11/24/episode-review-columbo-murder-under-glass/">blowfish poison</a>. Many poisons derived from plants have also been used for villainous purposes in fiction.</p>
<p>In the AMC TV series “<a href="https://www.imdb.com/title/tt0903747/">Breaking Bad</a>,” high school chemistry teacher Walter White uses a compound called ricin to murder the business executive Lydia Rodarte-Quayle. <a href="https://www.ncbi.nlm.nih.gov/books/NBK441948/">Ricin is a very potent poison</a> derived from the castor bean <em>Ricinus communis</em> and can be especially lethal if inhaled. Once this compound gets inside a cell, it <a href="https://doi.org/10.3390/ijms20051181">damages a structure called a ribosome</a> that’s responsible for synthesizing proteins essential to the cell’s function. Ingesting ricin could result in intestinal bleeding, organ damage and death.</p>
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<figcaption><span class="caption">It wasn’t Stevia that Lydia sweetened her tea with in ‘Breaking Bad’.</span></figcaption>
</figure>
<p>Sometimes, particular organs are much more susceptible to the effects of a poison. Physicians use <a href="https://cen.acs.org/articles/83/i25/Digoxin.html">digitalis medicines like digoxin</a>, which are derived from members of the foxglove family of plants, to treat congestive heart failure and heart rhythm problems. When administered in sufficiently high doses, however, they can lead to heart failure and death. By interfering with a protein in heart cells called the <a href="https://pubmed.ncbi.nlm.nih.gov/6328127/">sodium-potassium pump</a>, they can decrease the rate of electrical impulses in the heart and increase the strength of its contractions. This can result in a dangerous type of irregular heartbeat called ventricular fibrillation and lead to death.</p>
<p>The villain of the James Bond film “<a href="https://www.imdb.com/title/tt0381061/">Casino Royale</a>,” Le Chiffre, has his girlfriend attempt to kill Bond by poisoning his martini with digitalis. At high doses, digitalis drugs can alter the activity of the autonomic nervous system, which controls unconscious bodily functions like heart pumping. </p>
<figure>
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<figcaption><span class="caption">Poison is one way to win a poker game.</span></figcaption>
</figure>
<p>TV characters are not immune to the dangers of poisonous mushrooms. One particularly potent fungus, <em>Amanita verna</em>, is known as the “destroying angel.” In the ITV TV series “<a href="https://www.imdb.com/title/tt0118401/?ref_=nv_sr_srsg_0">Midsomer Murders</a>,” puppet show owner and presumed upstanding citizen Evelyn Pope uses this mushroom to fatally poison chef Tristan Goodfellow as part of her murder spree of the inheritors of an estate. This mushroom contains <a href="https://doi.org/10.1016/j.wem.2017.10.002">various chemicals called amatoxins</a> that are thought to inhibit the activity of a specific enzyme critical for the production of <a href="https://www.genome.gov/genetics-glossary/messenger-rna">messenger RNA</a>, or mRNA, a molecule essential to protein synthesis in cells. Because ingested amatoxins mainly target the liver, these poisons can severely disrupt the <a href="https://theconversation.com/helping-the-liver-regenerate-itself-could-give-patients-with-end-stage-liver-disease-a-treatment-option-besides-waiting-for-a-transplant-191826">liver’s ability to repair itself</a>, leading to loss of function that will prove fatal without liver transplantation.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/_0g3mw6XkRg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">They don’t call it the “destroying angel” for nothing.</span></figcaption>
</figure>
<p>Another highly popular poison in detective and mystery stories is <a href="https://emergency.cdc.gov/agent/strychnine/basics/facts.asp">strychnine</a>. In the Agatha Christie story “<a href="https://www.agathachristie.com/stories/the-mysterious-affair-at-styles">The Mysterious Affair at Styles</a>,” Alfred Inglethorp and his lover Evelyn Howard use this poison to kill Inglethorp’s wife and wealthy country manor owner, Emily Inglethorp.</p>
<p>Strychnine, which comes from seeds of the <em>Strychnos nux-vomica</em> tree, <a href="https://doi.org/10.1039/d1np00079a">affects the nervous system</a> by blocking a neurotransmitter called glycine in the spinal cord and brainstem. Normally, glycine slows down the activity of neurons and prevents muscle contractions. By blocking glycine, strychnine ingestion can result in excessive activation of neurons and muscles, leading to a series of full-body muscle spasms that can become so intense that they cause respiratory arrest and death.</p>
<p>Many more poisons exist in nature than described here. Aside from potentially enhancing the enjoyment of detective and mystery stories, understanding the mechanisms of how these poisons work can provide an added appreciation for the complexity of the effects foreign chemicals have on the human body.</p><img src="https://counter.theconversation.com/content/199251/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brad Reisfeld does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>From ‘Breaking Bad’ to James Bond, certain chemicals are popular options for characters looking to achieve nefarious ends.Brad Reisfeld, Professor of Chemical and Biological Engineering, Colorado State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1982702023-02-06T13:28:58Z2023-02-06T13:28:58ZIs the gruesome fun in Netflix’s ‘Wednesday’ realistic? What science says about getting eaten by piranhas and poisoned by nightshade<figure><img src="https://images.theconversation.com/files/507698/original/file-20230201-10326-3f2ayo.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C700%2C467&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Piranhas do bite, but can they kill you?</span> <span class="attribution"><a class="source" href="https://pyxis.nymag.com/v1/imgs/38e/7d1/fa450bcea450386b68bbb63d5ceeb5db1d-recaps-wednesday-1.rhorizontal.w700.jpg">Netflix</a></span></figcaption></figure><p><em>Editor’s note: This article contains minor spoilers for the Netflix series “Wednesday.”</em></p>
<p>The popular Netflix series “Wednesday” chronicles the adventures of the Addams family’s teen daughter. After her parents send her to Nevermore Academy, a school for “outcasts,” Wednesday Addams, played by Jenna Ortega, is pulled into a perplexing murder mystery. The show is infused with elements of the supernatural but also contains scenes that may leave viewers wondering, “Could that really happen in real life?”</p>
<p>I’m a <a href="https://scholar.google.com/citations?user=mN6ZaFkAAAAJ&hl=en">professor of pharmacology and toxicology</a> at the Indiana University School of Medicine, where we study the effects of drugs and poisons on the body. Some of the scenes in “Wednesday” raise intriguing questions about chemical and biological hazards that inspired me to investigate what science has to say about them.</p>
<h2>Piranhas in the pool</h2>
<p>One of the most memorable scenes involves Wednesday exacting revenge on her brother’s bullies by dumping hungry piranhas in their swimming pool. Most of the swimmers escape except for one unlucky guy who gets a wee bit chewed up. What is the likelihood that piranhas would attack someone in a pool?</p>
<p><a href="https://www.britannica.com/animal/piranha-fish">Piranhas</a> are freshwater fish indigenous to South American rivers and lakes. Their reputation as a ferocious carnivore that can reduce their prey to bones in seconds was <a href="https://www.mentalfloss.com/article/50356/how-teddy-roosevelt-turned-piranhas-ferocious-maneaters">popularized by Teddy Roosevelt</a> following his trip to the Amazon. However, the fish he witnessed eating a cow were purposefully starved before the display. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/Di310WS8zLk?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Dumping piranhas into a school pool could get you expelled.</span></figcaption>
</figure>
<p>In reality, not all piranhas are carnivores, and the rare attack on humans is typically limited to a single bite. <a href="https://scholar.google.com/citations?user=ZjGiZ_cAAAAJ&hl=en">Gregory A. Lewbart</a>, a professor of aquatic, wildlife and zoological medicine at North Carolina State University, once swam with piranhas in the Ecuadorian Amazon, as many people do every day without incident. “Fatal attacks are either <a href="https://doi.org/10.1080/01650520600630683">extremely rare or have not occurred</a>,” Lewbart told me. “It sounds like the only humans consumed by piranhas are people who already died from drowning.”</p>
<p>Even if Wednesday were able to procure a carnivorous species deprived of food, there’s still the problem of being dumped into a chlorinated pool. Lewbart explained that the chlorine would cause rapid damage to the fish’s gills and <a href="https://doi.org/10.1577/1548-8659(1975)104%3C800:CMIF%3E2.0.CO;2">reduce the ability of their blood to carry oxygen</a>, leading to death. These piranhas would be in shock and unlikely to swim across the length of a pool to mount an unprovoked attack. “I can almost guarantee a piranha or any fish dumped into a swimming pool would not be thinking about feeding,” Lewbart told me.</p>
<h2>Snacking on potpourri</h2>
<p>During a family therapy session, Wednesday’s brother Pugsley, played by Isaac Ordonez, mistakes a bowl of potpourri for candy and begins to devour it. Potpourri is a mixture of dried flower petals, herbs and spices used to fragrance a room. What would happen if someone ate it?</p>
<p>Potpourri is <a href="https://medlineplus.gov/ency/article/002716.htm">generally considered</a> to be nontoxic. However, essential oils are commonly added to potpourri to enhance and extend its smell. These highly concentrated plant extracts can potentially cause a <a href="https://doi.org/10.1007%2Fs40521-020-00275-7">skin rash</a> or irritation to the eyes, mouth and throat.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of bowl of potpourri" src="https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507718/original/file-20230201-17228-vyv5pl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Potpourri may look delicious, but whether it’s edible is another question.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/bowl-of-pot-pourri-potpourri-royalty-free-image/911657360">Rhys Hayward/Moment via Getty Images</a></span>
</figcaption>
</figure>
<p>While ingesting a small amount of potpourri is probably not too dangerous for humans, veterinarians have issued <a href="https://www.bergencountyveterinarycenter.com/potpourri-and-toxicity-to-pets.html">warnings for dogs and cats</a>, as excessive amounts could lead to gastrointestinal problems or adverse liver effects. Beyond a sensitivity to the essential oils, the contents of potpourri can also pose a choking hazard to your pet.</p>
<h2>Blast fishing</h2>
<p>In one scene, the Addams kids go fishing with Pugsley’s “favorite bait”: grenades. After they toss a grenade into the pond, the explosion produces a ready supply of dead fish for the taking. To learn more about “blast fishing,” I consulted with <a href="https://scholar.google.com/citations?user=JJKxFDoAAAAJ&hl=en">Rachel Lance</a>, who studies explosives and blast trauma at Duke University.</p>
<p>“The grenade method may technically work,” Lance told me. “Grenades almost certainly could cause swim bladder trauma as a result of the explosive shock wave, which would bring the unfortunate fish to the surface belly up.” </p>
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<figcaption><span class="caption">Blast fishing can be harmful for both marine life and people.</span></figcaption>
</figure>
<p>Lance added that fish are quite blast-resistant, so a powerful explosive such as an M-80 firecracker, dynamite or homemade bomb would be needed. And even with large explosions, the technique carries far more risk than it’s worth. “<a href="https://www.youtube.com/watch?v=FHrlXY9Gd6c">Jacques Cousteau</a> dove underwater after a bout of blast fishing, and he found it to be sadly ineffective, with 90% of the fish that had been killed sinking to the bottom where they could not be easily collected, and a meager 10% rising to the top,” recalled Lance.</p>
<p>Given the danger of explosives, not to mention their inefficiency and collateral damage to the ecosystem, blast fishing is <a href="https://stopillegalfishing.com/issues/blast-fishing/">illegal in many parts of the world</a>.</p>
<h2>Nightshade poisoning</h2>
<p>Nightshade poisoning was deduced as the cause of death for one of the characters based on foaming saliva, dilated pupils, mental confusion and bluish skin. What is nightshade and can it be used as a poison?</p>
<p>Nightshades include many different varieties of plants, some of which are diet staples for many, like tomatoes, potatoes and peppers. Other varieties are to be avoided, such as the aptly named deadly nightshade (<em>Atropa belladonna</em>). Deadly nightshade is a shrub with dark green leaves adorned with purple, bell-shaped flowers and dark purple berries. But don’t let the beauty of this belladonna fool you; ingest any part of this plant, especially the sweet-tasting berries, and it could be your last meal.</p>
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<a href="https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of flower and berries of Deadly Nightshade" src="https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/507717/original/file-20230201-19-8x5vym.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It’s called a deadly nightshade for a reason.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/flower-and-berries-of-deadly-nightshade-royalty-free-image/523717434">Naturfoto Honal/Corbis Documentary via Getty Images</a></span>
</figcaption>
</figure>
<p>People have been exploiting the poisonous properties of deadly nightshade <a href="https://pubmed.ncbi.nlm.nih.gov/17575737/">since Roman times</a>, but the plant has medicinal and cosmetic uses as well. The berries are rich in <a href="https://www.drugs.com/mtm/atropine-ophthalmic.html">atropine</a>, a chemical that enlarges the pupils by relaxing the muscles in the eye. This became <a href="https://archive.org/details/fritzspieglssick0000spie">a fad among women during the Renaissance</a> and can be used by ophthalmologists to dilate the pupil for an eye exam. Atropine is also included in the <a href="https://list.essentialmeds.org/medicines/10">World Health Organization’s Essential Medicines list</a> to reduce saliva production in surgeries and treat some poisonings and eye conditions.</p>
<p><a href="https://medlineplus.gov/druginfo/natural/531.html">Symptoms of deadly nightshade poisoning</a> include rapid heartbeat, blurred vision, vomiting, hallucinations, seizures and coma. These symptoms take at least 15 minutes to appear; they are not as immediate as depicted in “Wednesday.” And while some victims may have <a href="https://plantura.garden/uk/trees-shrubs/deadly-nightshade/deadly-nightshade-overview">blue-tinged skin</a> because of low oxygen levels in the blood, it is not a hallmark of deadly nightshade poisoning. Other conditions, <a href="https://www.webmd.com/skin-problems-and-treatments/argyria-overview">including silver poisoning</a>, can also cause blue skin.</p>
<p>“Wednesday” is the latest Hollywood hit that exaggerates what’s possible to advance a good story. Even if a show doesn’t quite get the science right, investigating what’s true can be educational.</p><img src="https://counter.theconversation.com/content/198270/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bill Sullivan does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>From eating potpourri to blast fishing, Wednesday Addams and her friends and family get involved in a number of grisly hijinks. But could they happen in real life?Bill Sullivan, Professor of Pharmacology & Toxicology, Indiana UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1970142022-12-22T06:29:34Z2022-12-22T06:29:34ZThe peculiar history of thornapple, the hallucinogenic weed that ended up in supermarket spinach<figure><img src="https://images.theconversation.com/files/502496/original/file-20221222-17-jd44zw.jpg?ixlib=rb-1.1.0&rect=0%2C1%2C1000%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/white-flower-poisonous-vespertineflowering-thornapple-plant-2199701639">Shutterstock</a></span></figcaption></figure><p>The agent that contaminated baby spinach, prompting the recent <a href="https://www.foodstandards.gov.au/industry/foodrecalls/recalls/Pages/Baby-spinach-recall.aspx">national recall</a>, has been <a href="https://www.theguardian.com/world/2022/dec/21/weed-responsible-for-hallucinogenic-spinach-recall-identified-as-applethorn">revealed</a>. It’s a weed, not deliberate misadventure or a chemical contaminant. </p>
<p>The culprit is <a href="https://weeds.dpi.nsw.gov.au/Weeds/Commonthornapple">thornapple</a>, otherwise known as jimsonweed or, to give it its scientific name, <em>Datura stramonium</em>.</p>
<p>Multiple cases of poisoning, now extending <a href="https://www.foodstandards.gov.au/industry/foodrecalls/recalls/Pages/Baby-spinach-recall.aspx">into their hundreds</a>, have been reported across numerous Australian jurisdictions in the past couple of weeks, following the consumption of baby spinach.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1605509424260517889"}"></div></p>
<h2>From blurred vision to hallucinations</h2>
<p><a href="https://www.foodstandards.gov.au/industry/foodrecalls/recalls/Pages/Baby-spinach-recall.aspx">Symptoms included</a> blurred vision, dry mouth, abdominal cramps – and quite significant hallucinations. These are all classic symptoms of “<a href="https://www.ncbi.nlm.nih.gov/books/NBK534798/">anticholinergic poisoning</a>”. </p>
<p>“Toxidromes” are patterns of symptoms that give medical responders clues to what agent might be responsible for a poisoning. Not all types of poisoning come with their own toxidrome, but of those that do, anticholinergic poisoning is one of the most colourful and well-characterised.</p>
<p>There would be very few medical students who would not be familiar with some version of the <a href="https://www.rch.org.au/clinicalguide/guideline_index/Anticholinergic_Syndrome/">mnemonic</a></p>
<blockquote>
<p>red as a beet, dry as a bone, blind as a bat, mad as a hatter, hot as a hare, full as a flask. </p>
</blockquote>
<p>This reflects the characteristic flushing, drying up of sweating and saliva, dilation of pupils, “altered mental state”, fever and, in some occasions, urinary retention. Additional features can include stomach cramps. An “altered mental state” can manifest as delirium, hallucinations, agitation, restlessness or confusion, together with possible changes in speech and gait, among other effects.</p>
<p>All of these effects are due to toxins that block the action of an essential neurotransmitter (chemical messenger in the nervous system), <a href="https://www.ncbi.nlm.nih.gov/books/NBK11143/">acetylcholine</a> and its receptor.</p>
<p>These are vital cogs in the autonomic nervous system, the maintenance janitor of our nervous system. Fundamental as it is to our survival, it is hardly a surprise that any disturbance of its function results in fairly dramatic effects.</p>
<p>It is also similarly not that surprising that humans have known about plant materials that exert these effects for as long as humans have been interested in using plants for either therapeutic or nefarious purposes.</p>
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<strong>
Read more:
<a href="https://theconversation.com/i-have-always-wondered-why-are-some-fruits-poisonous-83210">I have always wondered: why are some fruits poisonous?</a>
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<h2>A rich history of using these plants</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Woman with a mirror" src="https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=702&fit=crop&dpr=1 600w, https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=702&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=702&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=882&fit=crop&dpr=1 754w, https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=882&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/502518/original/file-20221222-26-76w7a3.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=882&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Titian’s Woman with a Mirror is thought to depict use of deadly nightshade to dilate the pupils.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Tiziano,_donna_allo_specchio,_1515_ca._01.JPG">Sailko/Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6412926/">Tropane alkaloids</a> are both valuable, and potentially dangerous, compounds with a rich history.</p>
<p>Ancient Egyptians reportedly burned <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2844275/">henbane</a> and inhaled its smoke as one of the earliest treatments for asthma.</p>
<p><a href="https://www.rcpe.ac.uk/heritage/deadly-nightshade-botanical-biography">Deadly nightshade</a> was used in Renaissance Italy as both a poison and as a cosmetic agent, with drops of extract used to dilate the pupils of wealthy ladies. Titian’s <a href="https://www.fs.usda.gov/wildflowers/ethnobotany/Mind_and_Spirit/belladonna.shtml">Woman with a Mirror</a> is thought to depict this. </p>
<h2>Then there were the naked soldiers</h2>
<p>Thornapple has its own peculiar story, which is impossible to confirm but may give us clues to the origin of its other name, jimsonweed.</p>
<p>There is a <a href="https://wydaily.com/news/local/2021/10/22/oddities-curiosities-the-colonial-case-of-the-mysterious-jimson-weed/">widely reported story</a> from colonial times in Jamestown, Virginia, where British soldiers were sent to quell an uprising in Bacon in the 1600s. </p>
<p>The soldiers prepared a meal from the plant and shortly afterwards, were entirely incapacitated. They were, <a href="https://docsouth.unc.edu/southlit/beverley/beverley.html">apparently</a> “stark naked … sitting up in a corner, like a monkey, grinning and making mows at them”. Another of the affected soldiers would “fondly kiss, and paw his companions”. </p>
<p>This was regarded as a something of a worry in an armed expeditionary force. So the plant earned the additional names “devil’s snare” or “devil’s trumpet”.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/little-shop-of-horrors-the-australian-plants-that-can-kill-you-50842">Little shop of horrors: the Australian plants that can kill you</a>
</strong>
</em>
</p>
<hr>
<h2>Back in Australia</h2>
<p>Plants from the <em>Datura</em> genus and the closely related, woody cousin, angel’s trumpet, are widely grown for their decorative flowers around Australia. Occasionally some people deliberately consume them for their hallucinogenic effects, with misadventure requiring medical intervention not uncommon.</p>
<p>Every year, poisons centres and emergency departments around the country are involved in managing these recreational overdoses. </p>
<p>Accidental overdoses, such as the one affecting the baby spinach crop, are less common but not unheard of. One such outbreak was reported <a href="https://www.napolike.com/pozzuoli-pianta-velenosa-venduta-come-spinaci-8-intossicati-uno-e-grave">in Italy</a> earlier this year. </p>
<p>Unfortunately, thornapple is a hardy plant, with seeds that can reputedly last several decades. Without constant agricultural vigilance, contamination of plants meant for human consumption remains a possibility.</p>
<p>For those not anticipating the effects, poisoning can be quite disturbing, not just from the obvious physical effects, but from the disconcerting hallucinations. Fortunately, the treatment of such exposures, once identified, is usually relatively straightforward. </p>
<p>Given the characteristic toxidrome, and the efficiency of modern poisons information centres, outbreaks and sources can be identified very rapidly, and the public protected from further exposure, as has been the case here.</p><img src="https://counter.theconversation.com/content/197014/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Caldicott has previously been the recipient of an NH&MRC partnership grant.</span></em></p>Thornapple or jimsonweed and related plants have an interesting history – from an early asthma treatment to intoxicated British soldiers.David Caldicott, Senior lecturer, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1947162022-11-17T03:58:49Z2022-11-17T03:58:49ZToxic poppy seeds are sending people to hospital. 3 experts explain what’s behind the latest food scare<figure><img src="https://images.theconversation.com/files/496004/original/file-20221117-17-madsvi.jpg?ixlib=rb-1.1.0&rect=4%2C1%2C994%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Poisonous poppy seeds have sent a number of people around Australia to hospital with severe symptoms – from muscle cramping and spasms to seizures and cardiac arrests – prompting a nationwide recall of <a href="https://www.foodstandards.gov.au/media/Pages/Additional-brands-listed-in-national-poppy-seed-recall.aspx">certain batches and brands</a> of this common pantry item.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1592706604905873408"}"></div></p>
<p>We work for two major poisons information services (<a href="https://www.health.nsw.gov.au/news/Pages/20221115_00.aspx">New South Wales</a> and <a href="https://www.childrens.health.qld.gov.au/chq/our-services/queensland-poisons-information-centre/">Queensland</a>), where we have been advising and caring for people with poppy seed poisoning. There have also been cases in <a href="https://www.health.vic.gov.au/health-alerts/health-warning-on-on-poppy-seeds">Victoria</a>, Australian Capital Territory, <a href="https://glamadelaide.com.au/urgent-recall-on-two-popular-poppy-seed-brands-amid-poisoning-concerns/">South Australia</a> and <a href="https://ww2.health.wa.gov.au/Media-releases/2022/November/WA-Health-warns-community-of-severe-reactions-after-consuming-poppy-seed-tea">Western Australia</a>. </p>
<p>To date, there have been around 32 cases of poppy seed toxicity reported in Australia over the past month, all in adults.</p>
<p>This is what we know about what’s behind these cases and what you need to do if you’ve consumed poppy seeds recently, or have poppy seeds in your kitchen cupboards.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/people-want-to-use-bleach-and-antiseptic-for-covid-and-are-calling-us-for-advice-168660">People want to use bleach and antiseptic for COVID and are calling us for advice</a>
</strong>
</em>
</p>
<hr>
<h2>How could these poppy seeds be dangerous?</h2>
<p>The poppy seeds involved in the latest national recall are non-food grade seeds that are not intended for human consumption and are not safe to consume. Investigations are under way to determine how non-food grade seeds ended up in the shops.</p>
<p>Food-grade poppy seeds – the type that you’d usually see sprinkled on cake or bread – are not dangerous.</p>
<p>Poppy seeds come from the poppy plant <em>Papaver somniferum</em>. This plant produces a number of chemicals called alkaloids. Some, like morphine and codeine, have been used medicinally for thousands of years to treat pain and other conditions.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Poppy plant Papaver somniferum" src="https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=413&fit=crop&dpr=1 600w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=413&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=413&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Poppy seeds come from the plant <em>Papaver somniferum</em> and are used to make medicines, as well as food products.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/opium-poppy-heads-close-papaver-somniferum-2004569264">Shutterstock</a></span>
</figcaption>
</figure>
<p>Other naturally occurring poppy alkaloids – such as thebaine, noscapine, laudanosine and papaverine – are less-well described in terms of their effects on humans, but they can have a wide range of toxic effects.</p>
<p>Different varieties of poppy plants contain different amounts of these alkaloids.</p>
<p>Some have very low amounts, which tend to be used to produce food-grade poppy seeds. Varieties with higher amounts are used to produce medicines, such as morphine and codeine.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/weekly-dose-codeine-doesnt-work-for-some-people-and-works-too-well-for-others-58067">Weekly Dose: codeine doesn't work for some people, and works too well for others</a>
</strong>
</em>
</p>
<hr>
<h2>What happened recently then?</h2>
<p>The non-food grade poppy seeds that incorrectly entered the human food supply contain high amounts of the alkaloid thebaine. </p>
<p>Thebaine has very different effects to morphine. <a href="https://pubmed.ncbi.nlm.nih.gov/31670127/">In large doses</a> it causes severe and prolonged muscle cramps, spasms, seizures and cardiac arrests, as seen in the recent cluster of poisonings. </p>
<p>High concentrations of thebaine have been identified in the blood of affected people in this latest cluster.</p>
<p>To our knowledge, this is the first time that thebaine has entered the food chain in Australia. However, there are a couple of reports of people who have had severe toxicity after consuming non-food grade poppies in recent decades.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/indian-viagra-herbal-drug-kamini-contains-morphine-and-can-quickly-lead-to-dependence-191509">'Indian Viagra' – herbal drug Kamini contains morphine and can quickly lead to dependence</a>
</strong>
</em>
</p>
<hr>
<h2>How many poppy seeds are we talking about?</h2>
<p>All reported cases in the current cluster at the time of the recall occurred after people consumed poppy seeds as part of a drink – similar to a brewed tea. </p>
<p>Most people had consumed more than 100g poppy seeds (about 11 tablespoons). Although, 50g (5-6 tablespoons) may be sufficient to cause poisoning. Thebaine can build up in the body if you ingest it several times over the same day.</p>
<p>There have been no reports to date of people being poisoned after eating poppy seeds in baked goods. However, the investigation is ongoing. Owing to the nature of the contamination, we’d recommend avoiding poppy seeds from <a href="https://www.foodstandards.gov.au/media/Pages/Additional-brands-listed-in-national-poppy-seed-recall.aspx">affected brands</a> in any form.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1000%2C666&q=45&auto=format&w=1000&fit=clip"><img alt="Bread rolls with poppy seeds on brown paper" src="https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1000%2C666&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">So far, there have been no poisonings reported after eating poppy seeds in bread or cake.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/kaiser-rolls-poppy-seeds-bakery-concept-1043931433">Shutterstock</a></span>
</figcaption>
</figure>
<h2>What if I have poppy seeds at home?</h2>
<p>The non-food grade poppy seeds we’re currently concerned about likely entered the food supply in the past two months. So, if you bought poppy seeds <a href="https://www.health.vic.gov.au/health-alerts/health-warning-on-poppy-seeds">before September 2022</a>, these are likely to be safe. </p>
<p>If you’ve bought poppy seeds in the past two months and these <a href="https://www.foodstandards.gov.au/industry/foodrecalls/recalls/Pages/default.aspx?k=poppy">are listed</a> as part of the national recall, you may be at risk.</p>
<p>You can throw them in the bin or return them to where you bought them for a refund.</p>
<h2>What if I’ve eaten poppy seeds or drunk the tea?</h2>
<p>If you or someone you know develops the following symptoms after consuming poppy seeds, seek urgent medical assistance by calling triple zero:</p>
<ul>
<li>severe muscle cramping, muscle spasms and abnormal movements </li>
<li>seizures </li>
<li>collapses or is unresponsive.</li>
</ul>
<p>If symptoms are mild, or you’re not sure if these are because of consuming poppy seeds, call the Poisons Information Centre for advice (details below).</p>
<p>If you’ve consumed poppy seeds more than four hours ago and you feel fine, you can be reassured. That’s because these poisoning symptoms typically happen quickly, within four hours. </p>
<p>If you’ve consumed a large number of poppy seeds as a drink, especially from an affected batch of seeds, in the past four hours, go to the emergency department regardless of symptoms.</p>
<hr>
<p><em>If this article raises health concerns for you or for someone you know about consuming poppy seeds, call the <a href="https://www.poisonsinfo.nsw.gov.au/">Poisons Information Centre</a> from anywhere in Australia on 131 126. This evidence-base advice is available 24 hours a day. For life-threatening symptoms, call 000.</em></p>
<hr>
<p><em>Update: the article has been updated to reflect prior poppy poisonings.</em></p><img src="https://counter.theconversation.com/content/194716/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Darren Roberts is the Medical Director of the NSW Poisons Information Centre and a clinical Toxicologist at Royal Prince Alfred Hospital, Sydney.
</span></em></p><p class="fine-print"><em><span>Jared Brown is a Senior Poisons Specialist in Toxicovigilance at NSW Poisons Information Centre.</span></em></p><p class="fine-print"><em><span>Katherine Isoardi is the Director of the Clinical Toxicology Unit, Princess Alexandra Hospital, Brisbane, and Medical Director of Queensland Poisons Information Centre, Queensland Children’s Hospital, Brisbane, Australia</span></em></p>Affected poppy seeds made into a tea have led to seizures and cardiac arrests.Darren Roberts, Conjoint Associate Professor in clinical pharmacology and toxicology, St Vincent’s Healthcare Clinical Campus, UNSW SydneyJared Brown, Clinical Associate Lecturer, School of Pharmacy, University of SydneyKatherine Isoardi, Conjoint Associate Professor, Faculty of Medicine, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1890512022-09-06T00:14:15Z2022-09-06T00:14:15ZMicroplastics are common in homes across 29 countries. New research shows who’s most at risk<figure><img src="https://images.theconversation.com/files/481984/original/file-20220831-22-kajqnp.jpg?ixlib=rb-1.1.0&rect=0%2C1727%2C3808%2C2510&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Pexels</span></span></figcaption></figure><p>The evidence is clear: microplastics have contaminated <a href="https://www.nature.com/articles/d41586-021-01143-3">every corner of the globe</a>. We can’t escape exposure to these tiny bits of plastic (less than 5mm across) in the environment, which includes the homes where people <a href="https://www.nature.com/articles/7500165">spend most of their time</a>. </p>
<p>Recent research has discovered <a href="https://www.sciencedirect.com/science/article/pii/S0160412022001258">microplastics in the blood of humans</a>. However, the question of harm to humans <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7068600/">remains unresolved</a>. Despite concerns that some substances in microplastics could cause cancer or damage our DNA, we still have a poor grasp of the true risks of harm. </p>
<p>Our <a href="https://doi.org/10.1016/j.envpol.2022.119957">study of global microplastics</a> exposure inside homes across 29 countries, published today, shows people living in lower-income countries and young children are at greater risk of exposure. But our analysis of the chemical composition of microplastics in the home shows the specific health risk is surprisingly low. The study covered all the continents, including Australia.</p>
<p>The current challenge in understanding health risks from microplastics is the very limited data on toxic effects of the petrochemicals used in plastics production. </p>
<p>A recurrent theme in the environmental health research literature is that early concerns about suspect chemicals and related compounds, including those found in plastics, <a href="https://ec.europa.eu/environment/chemicals/non-toxic/pdf/NTE%20main%20report%20final.pdf">were eventually justified</a>. The effects of suspect substances only become clear after extensive toxicological and epidemiological research.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1164726964047028225"}"></div></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/youre-eating-microplastics-in-ways-you-dont-even-realise-97649">You're eating microplastics in ways you don't even realise</a>
</strong>
</em>
</p>
<hr>
<h2>What did the new study look at?</h2>
<p>Our study investigated three main questions relating to exposure to microplastics inside homes:</p>
<ol>
<li><p>what are the impacts in different countries across the world?</p></li>
<li><p>who is most at risk?</p></li>
<li><p>what are the specific health risks?</p></li>
</ol>
<p>We reached out to residents across 29 countries to collect their indoor atmospheric dust over a one-month period. At 108 homes sampled across these countries, we also collected information about households and behaviours. This helped us to better understand possible sources and causes of microplastics in dust. These data included:</p>
<ul>
<li><p>how often floors were cleaned</p></li>
<li><p>flooring type</p></li>
<li><p>presence or absence of children</p></li>
<li><p>number of people living in each home</p></li>
<li><p>percentage of full-time workers.</p></li>
</ul>
<p>In each home, atmospheric dust particles were collected in specially cleaned and prepared glass Petri dishes. We measured the levels of microplastics in the collected dust using a suite of microscopic techniques and instruments. We used <a href="https://www.chem.uci.edu/%7Edmitryf/manuals/Fundamentals/FTIR%20principles.pdf">infrared spectroscopy</a> – which identifies substances by how they interact with light – to determine the chemical composition of these microplastics.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/house-dust-from-35-countries-reveals-our-global-toxic-contaminant-exposure-and-health-risk-172499">House dust from 35 countries reveals our global toxic contaminant exposure and health risk</a>
</strong>
</em>
</p>
<hr>
<h2>What did the study find?</h2>
<p>The household dust contained a wide variety of synthetic <a href="https://www.livescience.com/60682-polymers.html">polymer</a> fibres. The most common were:</p>
<ul>
<li><p>polyester (as polyethylene terephthalate) at 9.1%, which is used in clothing fabrics</p></li>
<li><p>polyamide (7.7%), which is mainly used in textiles</p></li>
<li><p>polyvinyls (5.8%), which are used in floor varnishes</p></li>
<li><p>polyurethane (4.4%), which is used in surface coatings of furniture and in bedding</p></li>
<li><p>polyethylene (3.6%), a common polymer used in food containers and reusable bags. </p></li>
</ul>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1297&fit=crop&dpr=1 600w, https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1297&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1297&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1630&fit=crop&dpr=1 754w, https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1630&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/481992/original/file-20220831-1921-rycya7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1630&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="attribution"><a class="source" href="https://www.sciencedirect.com/science/article/pii/S026974912201171X?via%3Dihub">Author provided, The Conversation</a></span>
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<hr>
<p>We examined the prevalence and risk of microplastics according to the gross national income of each country, grouped as low, medium and high-income (such as Australia). Overall, we found lower-income countries have higher loads of microplastics, which were deposited at an average daily rate of 3,518 fibres per square metre. The rates for medium-income and high-income countries were 1,268 and 1,257 fibres/m²/day.</p>
<p>In low-income countries, the most prevalent synthetic polymer fibres were made of polyurethane (11.1% of all fibres in samples). In high-income countries, polyamide and polyester were the most prevalent microplastic types (11.2% and 9.8% respectively). </p>
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<p><iframe id="46JpN" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/46JpN/6/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p><iframe id="lX15k" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/lX15k/2/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
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<h2>So what are the health risks?</h2>
<p>For the first time we could attribute the health risk across countries according to incomes. Our analyses showed lower-income countries are at higher risk from microplastic pollution. This aligns with <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(17)32345-0/fulltext">research findings</a> on other toxic exposures – poorer countries and people are most at risk from pollution. </p>
<p>Nevertheless, we found the overall risk from microplastics exposure was low. We used the US Environmental Protection Agency’s <a href="https://www.epa.gov/iris">toxicity information</a> on polymers in the microplastics to calculate health risk based on the types and levels we detected. </p>
<p>Low-income countries had a higher lifetime risk of cancers due to indoor microplastic exposure at 4.7 people per million. High-income countries were next at 1.9 per million, with medium-income countries at 1.2 per million. </p>
<p>We attributed these differences in cancer risk to the different percentages of carcinogenic substances in the microplastics found in household dust.</p>
<p>We calculated the sum of the carcinogenic risk from inhalation and ingestion of the following chemicals in the microplastic fibres: vinyl chloride (polyvinyl chloride), acrylonitrile (polyacrylics) and propylene oxide (polyurethane). Because toxicity data for polymers are limited, the assessment was a minimum estimate of true risk.</p>
<p>Children are at greater risk irrespective of income, which is true for many types of environmental exposures. This is because of their smaller size and weight, and tendency to have more contact with the floor and to put their hands in their mouths more often than adults.</p>
<p>Our analysis indicated that the microplastics came mainly from sources inside the home, and not from outside. Synthetic polymer-based materials are used widely in high-income countries in products such as carpets, furniture, clothing and food containers. We anticipated levels of microplastic shedding in the home might be greater in these countries. </p>
<p>However, analysis of the data showed the only factor obviously linked with levels of microplastics in deposited dust was how often they were vacuumed. Frequent vacuuming reduces microplastic levels. </p>
<p>Vacuuming was more frequent in higher-income countries. Factors that influence the type of cleaning include people’s preference for sweeping and mopping versus vacuuming, as well as their access to and capacity to afford electronic vacuum cleaners.</p>
<figure class="align-center ">
<img alt="Person vacuuming a rug on a timber floor in the home" src="https://images.theconversation.com/files/482223/original/file-20220901-24-dmslui.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482223/original/file-20220901-24-dmslui.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482223/original/file-20220901-24-dmslui.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482223/original/file-20220901-24-dmslui.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482223/original/file-20220901-24-dmslui.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482223/original/file-20220901-24-dmslui.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482223/original/file-20220901-24-dmslui.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The levels of microplastics in the home appear to be reduced by frequent vacuuming.</span>
<span class="attribution"><span class="source">Liliana Drew/Pexels</span></span>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/were-all-ingesting-microplastics-at-home-and-these-might-be-toxic-for-our-health-here-are-some-tips-to-reduce-your-risk-159537">We're all ingesting microplastics at home, and these might be toxic for our health. Here are some tips to reduce your risk</a>
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</p>
<hr>
<h2>What can we do to reduce the risks?</h2>
<p>Based on this and our previous <a href="https://doi.org/10.1016/j.envpol.2021.117064">study data</a>, it is clear vacuuming regularly, instead of sweeping, is associated with less airborne microplastics indoors. Other obvious actions – such as choosing natural fibres for clothing, carpets and furnishings instead of petrochemical-based polymer fibres – can reduce the shedding of microplastics indoors.</p>
<p>Future research needs to focus on developing more complete profiles of the harmful effects of each of the toxic petrochemical-based synthetic polymers that can produce microplastics. This will give us a better understanding of the risks of exposure to these ubiquitous pollutants.</p><img src="https://counter.theconversation.com/content/189051/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Patrick Taylor received funding via an Australian Government Citizen Science Grant (2017-2020), CSG55984 ‘Citizen insights to the composition and risks of household dust’ (the DustSafe project). The VegeSafe and DustSafe programs are supported by publication donations to Macquarie University. He is a full-time employee of EPA Victoria, appointed to the statutory role of Chief Environmental Scientist.</span></em></p><p class="fine-print"><em><span>Neda Sharifi Soltani works for Macquarie University. She receives funding from Macquarie University. </span></em></p><p class="fine-print"><em><span>Scott P. Wilson has received funding from state and federal grants, corporate entities and philanthropic and charitable organisations to undertake his research . He undertook this work while employed by Macquarie University but is currently employed by Earthwatch Australia. </span></em></p>It’s impossible to escape exposure to microplastics and a new study confirms they’re in household dust around the world. But the health risks appear surprisingly low, and vacuuming makes a difference.Mark Patrick Taylor, Chief Environmental Scientist, EPA Victoria; Honorary Professor, School of Natural Sciences, Macquarie UniversityNeda Sharifi Soltani, Academic Casual, School of Natural Sciences, Macquarie UniversityScott P. Wilson, Chief Scientist, Earthwatch Australia, Honorary Senior Research Fellow, School of Natural Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1854472022-06-22T14:53:15Z2022-06-22T14:53:15ZHow Nairobi police failures let people get away with murder<figure><img src="https://images.theconversation.com/files/469994/original/file-20220621-17-iswo86.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A protest against police brutality outside parliament buildings in Nairobi.
</span> <span class="attribution"><span class="source">Patrick Meinhardt/AFP via Getty Images</span></span></figcaption></figure><p>At least <a href="https://www.standardmedia.co.ke/counties/article/2001361964/how-police-get-away-with-murder-report">one person gets killed every two days</a> in Kenya’s capital city, Nairobi. Most of these cases <a href="https://www.theguardian.com/global-development/2021/aug/17/the-wounds-wont-heal-kenyas-agonising-wait-for-justice-on-killings-by-police">are never resolved</a>. Only 94 murder cases were registered in Nairobi courts in 2021.</p>
<p>Nairobi is Kenya’s most populous city with more than <a href="https://www.knbs.or.ke/2019-kenya-population-and-housing-census-results/">four million people</a>. Like other major cities across Africa, it grapples with crime amid the strained provision of policing services. Kenya was ranked fourth in the <a href="https://www.statista.com/statistics/1223810/countries-with-the-highest-organized-crime-index-in-africa/">2021 Organised Crime Index</a> in Africa, with the <a href="https://www.knbs.or.ke/wp-content/uploads/2022/05/2022-Economic-Survey1.pdf">2022 Economic Survey</a> reporting that Nairobi regularly records the highest number of crimes in the country. </p>
<p>The swift progress the Directorate of Criminal Investigations made in investigating the murder of <a href="https://www.youtube.com/watch?v=PLDXux7pqkw">Dutch businessman Tob Cohen</a>, who had lived in Kenya for years, is largely unheard of. Investigators drawn from the directorate’s homicide unit took <a href="https://www.the-star.co.ke/news/2020-09-01-the-new-detective-in-town-how-dci-is-using-tech-to-crack-crime/">less than two months</a> to unravel Cohen’s 2019 murder and apprehend the perpetrators. </p>
<p>The country’s criminal justice system has a history of failing to crack <a href="https://nation.africa/kenya/news/unsolved-murders-high-profile-cases-yet-to-be-closed-207752">high-profile murders</a>. Cases are characterised by shambolic investigations that eventually lead to their being dismissed due to a lack of evidence.</p>
<p>Unresolved murders that have captured national attention include that of an International Criminal Court witness and whistleblower <a href="https://www.bbc.com/news/world-africa-31799171">Meshack Yebei</a> in 2015. He had been lined up to testify against Kenyan Deputy President William Ruto who was facing charges – that were later dropped – at The Hague-based court.</p>
<p>University student <a href="https://www.standardmedia.co.ke/nairobi/article/2000080721/police-say-varsity-student-keino-was-murdered">Mercy Keino’s body</a> was found along a major Nairobi highway in 2013. Her murderers are yet to face justice. The same holds for <a href="https://www.bbc.com/news/world-africa-40807425">Chris Msando</a>, an elections official who was tortured and killed just weeks before Kenya’s 2017 poll.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/justiceforsheila-highlights-the-precarious-lives-of-queer-people-in-kenya-183102">#JusticeForSheila highlights the precarious lives of queer people in Kenya</a>
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<p>Several challenges lie behind the failure of policing agencies to unravel murder cases. These include: poor evidence gathering; mistreatment and manhandling of potential witnesses; police negligence and recklessness; a lack of forensic capability; a poor legal and regulatory environment; and accusations of police involvement in extra-judicial killings.</p>
<p>Based on <a href="https://repository.kippra.or.ke/bitstream/handle/123456789/2745/policing.pdf?sequence=1&isAllowed=y">my research</a> on public sector reforms and policing in Kenya, I believe that the situation can be reversed. For this to happen, however, the <a href="https://www.npsc.go.ke/about-us/">National Police Service</a> must fully implement policing reforms that have been ongoing for the last 12 years.</p>
<h2>The challenges</h2>
<p><strong>Poor evidence gathering and mistreatment of potential witnesses:</strong> Under Kenya’s National Police Service <a href="https://www.nationalpolice.go.ke/downloads/category/5-acts.html">regulations</a>, the first responders at a crime scene are tasked with securing it for the collection of forensic evidence. However, this often doesn’t happen. It is common to see community members crowding around crime scenes, contaminating crucial evidence. </p>
<p>Witnesses are also critical to court processes. But there have been cases of police officers <a href="https://pettyoffences.org/kenyadrunk-and-disorderly-poor-mans-offence-a-cash-cow-for-police/">rounding up and mishandling anybody</a> at a crime scene. This includes potential witnesses, which makes them reluctant to cooperate with investigators. </p>
<p>Ideally, the details and contacts of potential witnesses ought to be recorded before they leave the scene. And the police must avoid detaining witnesses without justifiable reason.</p>
<p><strong>Police incompetence and recklessness:</strong> Police officers have been called out by the courts for carrying out <a href="https://www.standardmedia.co.ke/nairobi/article/2001327141/how-police-bungle-open-and-shut-murder-cases">shoddy investigations</a> or deliberately failing to submit critical evidence. </p>
<p>An example involves the killing of a member of parliament, <a href="https://nation.africa/kenya/blogs-opinion/opinion/how-police-bungle-probes-from-the-word-go-1067846">George Muchai,</a> and his three aides in 2015. The four men were <a href="https://nairobinews.nation.africa/witness-this-is-how-mp-muchai-was-killed/">shot and killed</a> on the streets of Nairobi. In court, however, police officers issued contradicting information on what happened. </p>
<p>In yet other cases, the courts have faulted police officers for relying on <a href="https://www.kenyans.co.ke/news/40149-suspect-3-murders-set-free-after-police-bungle-investigation">rumours and innuendo</a>. This has often resulted in acquittals due to a lack of evidence or even the prosecution of innocent suspects. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-violence-is-a-hallmark-of-kenyan-policing-and-what-needs-to-change-139878">Why violence is a hallmark of Kenyan policing. And what needs to change</a>
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<p><strong>Lack of forensic capability:</strong> Kenya has finally launched a <a href="https://www.president.go.ke/2022/06/13/president-kenyatta-officially-opens-dci-national-forensic-laboratory/">forensic laboratory</a> after a nearly 20-year delay caused by various <a href="https://nation.africa/kenya/blogs-opinion/blogs/why-newly-launched-dci-national-forensic-laboratory-was-overdue-3853436">corruption scandals</a>. Investigators previously relied on forensic laboratories in <a href="https://www.standardmedia.co.ke/national/article/2001447864/uhuru-kenyatta-launches-forensic-lab-ends-two-decade-wait-for-change">South Africa or Europe</a>. </p>
<p>In most cases, the cost of shipping samples abroad was borne by the families of victims, and it could take months to get results. </p>
<p><strong>Poor legal and regulatory environment:</strong> The National Police Service doesn’t have an official policy that guides officers on how to interact with communities. Its <a href="https://www.nationalpolice.go.ke/downloads/category/5-acts.html">Service Standing Orders</a> are archaic. They are not aligned with the constitution of Kenya, which spells out the rights of citizens even during emergencies. There are cases in which police officers have used <a href="https://www.africanews.com/2022/06/03/kenya-four-shot-dead-in-protest-against-dangerous-wildlife/">live ammunition</a> on unarmed citizens, alleging self defence. </p>
<p><strong>Inadequate data:</strong> Kenya doesn’t have a national crime register that would make it easier for policing agencies to identify habitual criminals within communities. </p>
<p><strong>Allegations of police involvement in extra-judicial killings:</strong> Police officers in Kenya have been <a href="https://www.hrw.org/news/2020/04/22/kenya-police-brutality-during-curfew">accused</a> of extra-judicial killings, making it nearly impossible for the public to expect them to be neutral during investigations and subsequent trials of suspects.</p>
<p>Many of the killings that are reported and documented involve the <a href="https://www.hrw.org/news/2020/02/20/kenya-no-letup-killings-nairobi-police">deaths of victims of police-related actions</a>. In such cases, investigations are often <a href="https://www.one.org/africa/blog/ndwiga-brothers-death-police-brutality-kenya/">bungled from the beginning</a> due to the ‘blue code of silence’ common within policing agencies. This sees many crimes involving police officers <a href="http://kenyalaw.org/caselaw/cases/view/193506/">deliberately covered up</a> by their colleagues. </p>
<p>A public oversight body, the <a href="http://www.ipoa.go.ke/">Independent Policing Oversight Authority </a>, is mandated to investigate cases of police misconduct. However, it has often met resistance from policing agencies in carrying out its work.</p>
<p>In addition, the country is yet to effect the <a href="https://www.knchr.org/Portals/0/Handbook%20On%20The%20National%20Coroners%20Service%20Act%2C%202017_2018.pdf">National Coroners Service Act 2017</a>. This law transfers the investigation of unnatural and violent deaths, including of people in police custody and prisons, from policing agencies to the office of a coroner general. </p>
<h2>The solutions</h2>
<p>First, evidence gathering and the treatment of witnesses needs to improve. The National Police Service must restore public confidence in its ability to investigate crimes. Police officers need to treat communities as partners in crime resolution, not as suspects.</p>
<p>Second, police incompetence needs to be addressed. The Internal Affairs Unit of the police rarely makes its findings on cases of misconduct open. Neither does it say what action was taken. The unit needs to work with communities to build public trust and ensure that cases of police negligence, recklessness and misconduct are addressed.</p>
<p>Third, forensic capabilities need to be improved. The <a href="https://www.president.go.ke/2022/06/13/president-kenyatta-officially-opens-dci-national-forensic-laboratory/">National Forensic Laboratory</a> is expected to improve officers’ ability to resolve complex crimes and support the criminal justice system through evidence-based investigations. </p>
<p>With changes in technology, the police service must ensure that the forensic laboratory stays updated and that it appoints officers with high integrity.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-do-police-forensic-scientists-investigate-a-case-a-clandestine-gravesite-recovery-expert-explains-171959">How do police forensic scientists investigate a case? A clandestine gravesite recovery expert explains</a>
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<p>Fourth, Kenya needs a stronger regulatory environment. The National Coroners Service Act, if implemented, <a href="https://www.amnestykenya.org/establish-coroner-generals-office-to-help-solve-rising-murder-mysteries/">is key</a>. This law would ensure that many unresolved murders are dealt with through forensic science.</p>
<p>Lastly, the country must address the issue of extra-judicial killings. This can be done by fixing weak forensic laws that help abet unlawful police killings and enable murder suspects to outmanoeuvre the law by either compromising investigators or court officials. </p>
<p>An audit of extra-judicial killings needs to be undertaken, leading to open and independent vetting of all police officers who come into contact with communities. </p>
<p>Continuous training, retraining, reevaluation and reconfiguration of how policing agencies conduct their business is critical. And officers who engage in crime, negligence and murders must be sanctioned heavily and removed from the service.</p><img src="https://counter.theconversation.com/content/185447/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Douglas Lucas Kivoi does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A host of problems are behind police failures, including poor evidence gathering and the mistreatment of witnesses.Douglas Lucas Kivoi, Principal Policy Analyst, Governance Department, The Kenya Institute for Public Policy Research and Analysis (KIPPRA)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1716052021-11-18T19:10:41Z2021-11-18T19:10:41ZWe can expect more COVID drugs next year. But we’ve wasted so much time getting here<figure><img src="https://images.theconversation.com/files/432513/original/file-20211117-15-vzhlc0.jpg?ixlib=rb-1.1.0&rect=1%2C7%2C997%2C658&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/creative-layout-pills-capsules-on-blue-1794385843">Shutterstock</a></span></figcaption></figure><p>Several COVID drugs <a href="https://theconversation.com/pfizers-pill-is-the-latest-covid-treatment-to-show-promise-here-are-some-more-171589">are in the pipeline</a> for 2022, some you can potentially take at home, others for use in hospital.</p>
<p>It’s taken almost two years of the pandemic to get here.</p>
<p>However, as <a href="https://bpspubs.onlinelibrary.wiley.com/doi/10.1002/prp2.866">we argue in our paper</a>, with more and larger collaborations, and focusing on repurposing the right drugs, we could have developed effective COVID drugs at scale, earlier.</p>
<p>Here’s what we can do better for the next pandemic.</p>
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<em>
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Read more:
<a href="https://theconversation.com/pfizers-pill-is-the-latest-covid-treatment-to-show-promise-here-are-some-more-171589">Pfizer's pill is the latest COVID treatment to show promise. Here are some more</a>
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<h2>First, some good news</h2>
<p>One recent study <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(21)00448-4/fulltext">found</a> a commonly prescribed drug for depression, fluvoxamine, given to people diagnosed with COVID-19 reduced their chance of symptoms deteriorating, needing to go to hospital, and dying.</p>
<p>There are four powerful features of this study. It was based on:</p>
<ul>
<li><p><strong>an existing human drug:</strong> drugs designed for another purpose can have extra therapeutic benefits. We also didn’t have to design a drug from scratch and knew a lot about tolerated doses, side-effects and drug interactions, over many years of people taking it</p></li>
<li><p><strong>earlier observation and data:</strong> the drug was chosen based on prior data showing people taking the same or similar drugs for depression did better with COVID-19 infection</p></li>
<li><p><strong>a large population:</strong> the study included enough people to give meaningful results</p></li>
<li><p><strong>an international collaboration:</strong> it is unclear why were there not many, thorough, studies of this type implemented at the very start of the pandemic. Collaboration helps with quicker recruitment and broader input into trial design.</p></li>
</ul>
<p>However, this example is the exception rather than the rule when it comes to finding COVID drugs. And during the pandemic, we’ve had several mis-steps.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-an-antidepressant-could-be-used-to-treat-covid-19-150295">Why an antidepressant could be used to treat COVID-19</a>
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<h2>We missed an early opportunity</h2>
<p>We can treat COVID with one of two broad strategies. One is to target or immobilise the virus itself. The other is to “treat the host”. This involves treating the body’s overwhelming response to the virus and the cause of most death and disease. Fluvoxamine mentioned above is an example of the latter.</p>
<p>However, we didn’t see any major strategy to “treat the host” in the early part of the pandemic, except with the decades-old corticosteroid drugs dexamethasone and budesonide.</p>
<p>Focusing more on “treating the host” would have <a href="https://bpspubs.onlinelibrary.wiley.com/doi/full/10.1002/prp2.620">bought us time</a> to produce vaccines and antiviral drugs, which typically take longer to develop.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1249753469449375745"}"></div></p>
<p>“Treating the host” is hardly radical. We’ve been doing this with existing medicines for <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5124618/">infectious diseases</a> for years.</p>
<p>In fact, we knew early on that we respond to COVID-19 in much the same way to being infected with other viral infections that can overwhelm the body, such as influenza and Ebola.</p>
<p>That’s not the only mis-step.</p>
<h2>We backed a few wrong horses</h2>
<p>It’s inevitable some existing drugs trialled initially for COVID-19 would fall by the wayside and never be used clinically. But we backed some of the wrong drugs, at the wrong doses. According to basic research and clinical knowledge of how drugs work in the body, this should have been obvious from the start.</p>
<p>Over a century after doctors unsuccessfully tried to treat the Spanish flu with quinine and its derivatives, <a href="https://jamanetwork.com/journals/jama/article-abstract/2764074">history was repeating itself</a>. We were asking if the related drug hydroxychloroquine could be used to treat COVID-19.</p>
<p>Researchers around the world conducted multiple trials with hydroxychloroquine, even after some others reported a lack of efficacy.</p>
<p>In the first year of the pandemic, <a href="https://www.nature.com/articles/d41586-021-01246-x">hydroxychloroquine was tested</a> in about 250 studies involving nearly 89,000 people, despite evidence it <a href="https://theconversation.com/hydroxychloroquine-for-covid-19-a-new-review-of-several-studies-shows-flaws-in-research-and-no-benefit-137869">does not help</a>.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1288861467152973824"}"></div></p>
<p>If we are to repurpose existing drugs, this needs to be based on our experience of that drug in humans with COVID-19, such as in the <a href="https://doi.org/10.1016/S2214-109X(21)00448-4">fluvoxamine example</a>. Alternatively, the drug needs to <a href="https://doi.org/10.1111/bcp.14551">fit with what we know</a> about how the virus causes disease and how the infection develops in humans.</p>
<p>If we are to repurpose drugs identified solely on cell-based laboratory studies, this must also be based on what we know about how the human body handles the drug and how the drug works in the body. We also need the relevant quality mathematical models to get the <a href="https://doi.org/10.1111/bcp.14964">dose right</a> for the early phase human studies. </p>
<p>Using such basic approaches to drug development, which we’ve known about for years, we could have foreseen that ivermectin and hydroxychloroquine would prove to be ineffective – before larger scale human trials were ever allowed to be conducted.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ivermectin-shows-us-how-hard-it-is-to-use-old-drugs-for-covid-heres-how-to-do-better-next-time-168192">Ivermectin shows us how hard it is to use old drugs for COVID. Here's how to do better next time</a>
</strong>
</em>
</p>
<hr>
<h2>We also backed too many small trials</h2>
<p>During the pandemic, there have been <a href="https://doi.org/10.1016/S2214-109X(21)00448-4">an estimated</a> 2,800 clinical trials for COVID drugs with fewer than 300 reported.</p>
<p>In one database of COVID-19 trials, <a href="https://www.nature.com/articles/d41586-021-01246-x">40% said</a> researchers were enrolling fewer than 100 patients, a sample size generally too small to be useful.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1283745968085561345"}"></div></p>
<p>For us to get a better idea if a COVID drug is safe and effective, we need larger, collaborative trials.</p>
<p>For example, the <a href="https://www.recoverytrial.net">RECOVERY trial</a>
enrolled about 45,000 people at 180 sites to test a range of potential COVID therapies. It showed the repurposed drug dexamethasone <a href="https://www.nejm.org/doi/full/10.1056/nejmoa2021436">reduced death rates</a>, changing standard practice.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dexamethasone-the-cheap-old-and-boring-drug-thats-a-potential-coronavirus-treatment-140932">Dexamethasone: the cheap, old and boring drug that's a potential coronavirus treatment</a>
</strong>
</em>
</p>
<hr>
<h2>How could we do better next time?</h2>
<p>We need to start thinking about ways of developing drugs for the early part of the next pandemic, considering what we’ve learned from this one. </p>
<p>This is essential if we are to have a range of safe, effective, cheap and available therapies for treating the host, to buy time to develop vaccines and antivirals.</p>
<p>We now know from global experiences the importance of rational choice of drugs for testing. We also know the importance of large clinical trials that come from major, international collaborations.</p>
<p>We also need to co-ordinate research efforts nationally, rather than compete for research dollars with other groups. Doing research in a pandemic is not like doing research in non-pandemic times. So this means countries such as Australia need to have their <a href="https://www.aph.gov.au/Parliamentary_Business/Committees/Senate/COVID-19/COVID19/Submissions">own centre for pandemic preparedness</a> or <a href="https://www.mja.com.au/system/files/issues/215_02/mja251143.pdf">centre for disease control</a> to co-ordinate research and funding priorities.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/coronavirus-pandemic-shows-its-time-for-an-australian-centre-for-disease-control-in-darwin-138724">Coronavirus pandemic shows it's time for an Australian Centre for Disease Control – in Darwin</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/171605/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>We’ve made a few mistakes in the past two years, when it comes to developing COVID drugs. Some were obvious and could have easily been avoided.Jennifer Martin, Professor of Medicine, University of NewcastleRichard John Head, Emeritus Professor, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1686602021-10-17T19:14:16Z2021-10-17T19:14:16ZPeople want to use bleach and antiseptic for COVID and are calling us for advice<figure><img src="https://images.theconversation.com/files/425387/original/file-20211008-21-ofpnwd.jpg?ixlib=rb-1.1.0&rect=0%2C1%2C1000%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/man-gargling-throat-holding-galss-1797736726">Shutterstock</a></span></figcaption></figure><p>Through our work at the <a href="https://www.poisonsinfo.nsw.gov.au">New South Wales Poisons Information Centre</a>, we’re used to receiving calls from concerned parents about what to do if their child has accidentally drunk some cleaning product. We also take calls from health professionals for advice on how to manage poisonings.</p>
<p>But over the past 18 months, we’ve seen an increasing number of people calling us about home remedies to prevent or cure COVID-19, particularly during an outbreak. They’re calling for advice before using items such as bleach or disinfectant. Or they’re calling to ask about side-effects after gargling, spraying or bathing in them.</p>
<p>When asked about the reason for using such products, callers say they did not know they could be harmful. Some say they thought it was better to do something, rather than nothing. </p>
<p>We’re concerned about the use of unproven COVID-19 home remedies. Here are some of the more common ones people have called our 24-hour poisons information service about, the types that can need medical care.</p>
<h2>1. Inhaling hydrogen peroxide</h2>
<p>Hydrogen peroxide is used in household disinfectants, chlorine-free bleaches, stain removers and hair dyes. And people have been calling about inhaling products containing hydrogen peroxide as a fine mist (called <a href="https://theconversation.com/what-are-nebulisers-and-how-could-they-help-spread-covid-19-155032">nebulising</a>).</p>
<p>Hydrogen peroxide (1-1.5%) mouthwashes <a href="https://pubmed.ncbi.nlm.nih.gov/34196047/">have been recommended</a> as an antiseptic before a dental procedure. However, results about whether it kills SARS-CoV-2, the virus that causes COVID-19, <a href="https://pubmed.ncbi.nlm.nih.gov/34399189/">are conflicting</a>.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1446942764235698177"}"></div></p>
<p>Nebulising hydrogen peroxide <a href="https://pubmed.ncbi.nlm.nih.gov/15298493/">can cause</a> irritation and swelling to the nose, throat and lungs. People can develop a cough and become short of breath; it can cause persistent damage to the lungs. These symptoms can be misinterpreted as a lung infection. If you have COVID-19, nebulising hydrogen peroxide can make you sicker and prolong your recovery. </p>
<p>People also report nausea and vomiting after nebulising hydrogen peroxide. The risk is increased with solutions of higher concentrations, although we do not believe any concentration is safe.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/thinking-of-trying-ivermectin-for-covid-heres-what-can-happen-with-this-controversial-drug-167178">Thinking of trying ivermectin for COVID? Here's what can happen with this controversial drug</a>
</strong>
</em>
</p>
<hr>
<h2>2. Gargling or swallowing antiseptics</h2>
<p>People have also called about gargling or swallowing strong antiseptics. These can cause irritation, swelling and pain to the mouth, as well as vomiting, diarrhoea and stomach pains. </p>
<p>Gargling or swallowing <a href="https://pubmed.ncbi.nlm.nih.gov/32348645/">corrosive</a> household cleaning products, such as the type you’d use in your kitchen or bathroom, is <a href="https://pubmed.ncbi.nlm.nih.gov/30689457/">particularly unsafe</a>. This can lead to life-threatening injuries, including rupture and bleeding of the upper gut, between the mouth and stomach.</p>
<p>A <a href="https://www.rollingstone.com/culture/culture-news/betadine-anti-vaxxer-covid-treatment-iodine-1225438/">recently promoted</a> home remedy is gargling antiseptics containing povidone-iodine.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1439996535815684105"}"></div></p>
<p>Some low concentration (0.5-1%) of products containing povidone-iodine can be gargled. And povidone-iodine (0.5%) mouthwash has been recommended before a dental procedure to <a href="https://pubmed.ncbi.nlm.nih.gov/34561086/">prevent transmission</a> <a href="https://pubmed.ncbi.nlm.nih.gov/34399189/">of SARS-CoV-2</a>.</p>
<p><a href="https://pubmed.ncbi.nlm.nih.gov/34628705/">Small pilot studies</a> have suggested that similar low-strength gargle and nasal sprays may shorten the survival of SARS-CoV-2 in the nose and mouth. But these results should be confirmed in larger studies. </p>
<p>Although some people are allergic to povidone-iodine, low concentration solutions are <a href="https://pubmed.ncbi.nlm.nih.gov/32520599/">usually safe</a> when applied in the nose or mouth for a few months. </p>
<p>However, many products contain much higher concentrations of povidone-iodine and other chemicals designed for use on the skin. </p>
<p>So swallowing, gargling or inserting these products in the nose is not recommended.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/gargling-with-iodine-wont-stop-you-getting-covid-167946">Gargling with iodine won't stop you getting COVID</a>
</strong>
</em>
</p>
<hr>
<h2>3. Bathing in bleach or disinfectant</h2>
<p>Bathing in household cleaning products (such as bleach or disinfectant), or applying them directly to the skin, can cause mild-to-moderate irritation and rashes.</p>
<p><a href="https://pubmed.ncbi.nlm.nih.gov/30689457/">Burns</a> <a href="https://pmj.bmj.com/content/59/693/472">can occur</a> <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7529601/">with stronger products</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/bleach-bonfires-and-bad-breath-the-long-history-of-dodgy-plague-remedies-137658">Bleach, bonfires and bad breath: the long history of dodgy plague remedies</a>
</strong>
</em>
</p>
<hr>
<h2>4. Spraying face masks</h2>
<p>Routinely spraying disinfectants into face masks, and then breathing in the fumes and residue for a prolonged period, can also harm.</p>
<p>This can result in irritation to the throat and lungs, dizziness, headache and nausea.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Person spraying disposable face mask" src="https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/425389/original/file-20211008-13-wdygg9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">If you spray your face mask, you’ll breathe in the fumes.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/hand-woman-spraying-alcohol-on-medical-1737708047">Shutterstock</a></span>
</figcaption>
</figure>
<h2>5. Taking high-dose vitamins</h2>
<p>Taking over-the-counter supplements, including vitamins, for a prolonged period is also a concern as high doses can have <a href="https://www.nps.org.au/australian-prescriber/articles/the-safety-of-commonly-used-vitamins-and-minerals">side-effects</a>:</p>
<ul>
<li><p>vitamin C can cause kidney stones</p></li>
<li><p>zinc can cause loss of taste or smell</p></li>
<li><p>vitamin D can cause high concentrations of calcium in the blood, with effects including headache, thirst and, uncommonly, seizures.</p></li>
</ul>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/vitamins-and-minerals-arent-risk-free-here-are-6-ways-they-can-cause-harm-165399">Vitamins and minerals aren't risk-free. Here are 6 ways they can cause harm</a>
</strong>
</em>
</p>
<hr>
<h2>It’s a confusing time</h2>
<p>COVID-19 is arguably the most confusing time in recent history for making decisions about our health care. While people debate if any of these proposed home remedies work, it is essential to also consider their potential harms. </p>
<p>Deaths and other complications are <a href="https://www.nps.org.au/australian-prescriber/articles/covid-19-and-the-quality-use-of-medicines-evidence-risks-and-fads">reported in people overseas</a> due to well-meaning use of proposed treatments and home remedies. We hope to avoid this in Australia. </p>
<hr>
<p><em>If this article raises concerns for you or for someone you know about a COVID-19 home remedy, call the <a href="https://www.poisonsinfo.nsw.gov.au/">Poisons Information Hotline</a> from anywhere in Australia on 131 126. This evidence-base advice is available 24 hours a day. For life-threatening symptoms, call 000.</em></p><img src="https://counter.theconversation.com/content/168660/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Darren Roberts is the medical director of the NSW Poisons Information Centre, and a clinical toxicologist/pharmacologist at Royal Prince Alfred Hospital and St Vincent’s Hospital (Sydney).</span></em></p><p class="fine-print"><em><span>Nicole Wright is the Acting Department Head, NSW Poisons Information Centre</span></em></p>They’re calling for advice before using bleach or disinfectant. Or they’re calling to ask about side-effects after gargling, spraying or bathing in them. It’s a worry.Darren Roberts, Conjoint Associate Professor in clinical pharmacology and toxicology, UNSW SydneyNicole Wright, Clinical Educator, Faculty of Pharmacy, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1671782021-09-02T05:27:41Z2021-09-02T05:27:41ZThinking of trying ivermectin for COVID? Here’s what can happen with this controversial drug<figure><img src="https://images.theconversation.com/files/419019/original/file-20210902-18-njx5bl.jpg?ixlib=rb-1.1.0&rect=1%2C1%2C997%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/clamart-france-august-22-2021-box-2028959327">Shutterstock</a></span></figcaption></figure><p>Westmead Hospital in Sydney’s west says it has treated a patient <a href="https://www.news.com.au/lifestyle/health/health-problems/westmead-hospital-patient-overdoses-on-online-cure-for-covid19/news-story/d5cc0998a98791af3b43bcaef42578b9">who overdosed</a> after taking the drug ivermectin, an unproven and potentially dangerous treatment for COVID-19.</p>
<p>The person went to hospital seeking treatment for diarrhoea and vomiting side-effects, after taking the drug, which is usually used to treat parasites. The person had ordered this and other unproven COVID “cures” online.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1433020559349084160"}"></div></p>
<p>While the patient did not die, <a href="https://www.tga.gov.au/covid-19-treatments-information-consumers-and-health-professionals">health authorities are concerned</a> at the number of people taking ivermectin, and warn against it for anyone else who may have COVID symptoms or has been diagnosed with the virus.</p>
<p>Other known ivermectin side-effects range from mild to the life-threatening, including seizures and coma.</p>
<h2>Why are people taking it?</h2>
<p>Ever since researchers showed ivermectin could kill SARS-CoV-2 (the virus that causes COVID-19) in the laboratory, there has been interest in whether the drug would also work to kill the virus <a href="https://theconversation.com/head-lice-drug-ivermectin-is-being-tested-as-a-possible-coronavirus-treatment-but-thats-no-reason-to-buy-it-135683">in the human body</a>.</p>
<p>So far, there is <a href="https://theconversation.com/a-major-ivermectin-study-has-been-withdrawn-so-what-now-for-the-controversial-drug-164627">no clinical evidence</a> it works to treat or prevent COVID-19. And there is widespread consensus people should not take ivermectin at home for COVID-19. </p>
<p>Organisations that recommend against it include: the <a href="https://www.who.int/news-room/feature-stories/detail/who-advises-that-ivermectin-only-be-used-to-treat-covid-19-within-clinical-trials">World Health Organization</a>, Australia’s <a href="https://covid19evidence.net.au/faqs/#Ivermectin">National COVID-19 Clinical Evidence Taskforce</a> and <a href="https://www.nps.org.au/ivermectin-and-covid-19">NPS Medicinewise</a>, the United State’s <a href="https://www.fda.gov/animal-veterinary/animal-health-safety-and-coronavirus-disease-2019-covid-19/cvm-letter-veterinarians-and-retailers-help-stop-misuse-animal-ivermectin-prevent-or-treat-covid-19">Food and Drug Administration</a>, and the <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD015017.pub2/full">Cochrane Library</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-major-ivermectin-study-has-been-withdrawn-so-what-now-for-the-controversial-drug-164627">A major ivermectin study has been withdrawn, so what now for the controversial drug?</a>
</strong>
</em>
</p>
<hr>
<h2>How are people getting hold of it?</h2>
<p>Despite this, <a href="https://www.theguardian.com/australia-news/2021/sep/01/australian-pharmacists-report-rise-in-customers-refusing-to-say-what-ivermectin-prescription-is-for">community pharmacists</a> have reported increased demand for ivermectin, with people seeking the drug as a possible COVID treatment.</p>
<p>In Australia, ivermectin is <a href="https://www.tga.gov.au/covid-19-treatments-information-consumers-and-health-professionals">approved to treat parasite infections in humans</a>. It’s also widely used in veterinary medicine to treat and prevent parasite infections.</p>
<p>However, as a prescription-only human medicine (known as <a href="https://www.healthdirect.gov.au/medicines/brand/amt,3069011000036101/stromectol">schedule 4</a>), you can only access ivermectin legally in Australia after approval from a doctor.</p>
<p>This is because, like all medicines, ivermectin is not 100% safe. It does have possible harmful side-effects and a doctor’s judgement is necessary to decide if ivermectin is safe and appropriate for each patient.</p>
<p>So ivermectin is currently only recommended to treat and prevent COVID-19 when used <a href="https://covid19evidence.net.au/faqs/#Ivermectin">as part of a clinical trial</a>, where patients can be more safely selected and carefully monitored.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1432747015507779586"}"></div></p>
<p>As well as more patients presenting to pharmacies with scripts, the Therapeutic Goods Administration <a href="https://www.tga.gov.au/media-release/risks-importing-ivermectin-treatment-covid-19">warns</a> about the danger of importing ivermectin products of unknown quality, bought over the internet.</p>
<p>This is risky because products may not contain the stated drug, may contain dangerous contaminants or much more of the drug than thought, which may result in an overdose.</p>
<p>Of most concern are reports from <a href="https://www.abc.net.au/radio/programs/worldtoday/warnings-against-ivermectin/13524184">Australia</a> and <a href="https://www.theguardian.com/commentisfree/2021/aug/31/a-human-is-not-a-horse-so-why-is-a-livestock-drug-sweeping-america-covid-ivermectin">overseas</a> of people buying and taking ivermectin products intended for animal use. People may be resorting to these types of products where they have been unable to access a script for human formulations of ivermectin.</p>
<h2>What does it do to your body?</h2>
<p>We know very little about what the drug does to humans, and the little we do know mostly comes from <a href="https://pubmed.ncbi.nlm.nih.gov/34149064/">its use in animals</a>.</p>
<p>When taken at the recommended dose, the drug is generally well tolerated. But ivermectin is known to cause mild side-effects such as diarrhoea, nausea, dizziness and sleepiness. Less common, but serious, side-effects include severe skin rashes and effects on the nervous system (causing tremor, confusion and drowsiness). </p>
<p>In higher doses, and overdose cases, these side-effects can be <a href="https://www.fda.gov/consumers/consumer-updates/why-you-should-not-use-ivermectin-treat-or-prevent-covid-19">more severe</a>. These include low blood pressure, problems with balance, seizures, liver injury, and it can even <a href="https://www.nejm.org/doi/full/10.1056/NEJMc1917344">induce comas</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/coronavirus-misinformation-is-a-global-issue-but-which-myth-you-fall-for-likely-depends-on-where-you-live-143352">Coronavirus misinformation is a global issue, but which myth you fall for likely depends on where you live</a>
</strong>
</em>
</p>
<hr>
<h2>The take-home message</h2>
<p>The public is understandably interested in medicines to treat and prevent COVID-19. However, <a href="https://theconversation.com/au/topics/covid-misinformation-103292">misinformation about ivermectin and others continues to circulate</a>. </p>
<p><a href="https://theconversation.com/how-well-do-covid-vaccines-work-in-the-real-world-162926">COVID-19 vaccination</a> remains the best way to reduce the risk of serious illness and death from COVID-19. Australia’s <a href="https://covid19evidence.net.au/">National COVID-19 Clinical Evidence Taskforce</a> provides the most up-to-date information about COVID-19 treatments and is a reliable source of information as new knowledge emerges.</p>
<hr>
<p><em>If you or a family member take ivermectin and have strong side-effects you should seek medical advice. Call the <a href="https://www.health.gov.au/contacts/poisons-information-centre">Poisons Information Centre</a> on 131 126. For life-threatening symptoms, call 000 for an ambulance.</em></p><img src="https://counter.theconversation.com/content/167178/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Associate Professor Wheate in the past has received funding from the ACT Cancer Council, Tenovus Scotland, Medical Research Scotland, Scottish Crucible, and the Scottish Universities Life Sciences Alliance. He is Fellow of the Royal Australian Chemical Institute and a member of the Australasian Pharmaceutical Science Association. Nial is science director of the medicinal cannabis company Canngea Pty Ltd, a board member of the Australian Medicinal Cannabis Association, and a Standards Australia committee member for sunscreen agents.</span></em></p><p class="fine-print"><em><span>Andrew McLachlan receives research funding from the NHMRC and the Sydney Pharmacy School receives research scholarship funding from GSK for a PhD student under his supervision. Andrew has served as a paid consultant on Australian government committees related to medicines regulation. Andrew does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article.</span></em></p><p class="fine-print"><em><span>Slade Matthews has served the Australian Therapeutic Goods Administration as an external evaluator for the Therapeutic Goods Evaluation Panel. He also serves on the NSW Poisons Advisory Committee as the pharmacologist member. Slade does not work for, consult or own shares in or receive funding from any company of organisation that would benefit from this article.</span></em></p>Side-effects for this unproven and potentially dangerous treatment range from vomiting and diarrhoea to seizures and a coma.Nial Wheate, Associate Professor of the Sydney Pharmacy School, University of SydneyAndrew McLachlan, Head of School and Dean of Pharmacy, University of SydneySlade Matthews, Senior Lecturer, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1470012020-10-26T12:00:34Z2020-10-26T12:00:34ZFan of black licorice? Beware of its dark side − it can be dangerous for your health<figure><img src="https://images.theconversation.com/files/363719/original/file-20201015-13-1edro0h.jpg?ixlib=rb-1.1.0&rect=10%2C40%2C6689%2C4416&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Black licorice gets its distinctive flavor from licorice root.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/heap-of-licorice-roots-and-black-salt-licorice-royalty-free-image/1171067902?adppopup=true">PicturePartners/Getty Images</a></span></figcaption></figure><p>Black licorice may look and taste like an innocent treat, but this candy has a dark side. On Sept. 23, 2020, doctors reported that black licorice was the culprit in the <a href="https://apnews.com/article/archive-04cf918055b735ea69483dd00e281253">death of a 54-year-old man in Massachusetts</a>. How could this be? Overdosing on licorice sounds more like a twisted tale than a plausible fact.</p>
<p><a href="https://wjsulliv.wixsite.com/sullivanlab">I am a toxicologist</a> and <a href="https://authorbillsullivan.com">author of the book</a> “<a href="https://www.nationalgeographicpartners.com/press/2019/10/-pleased-to-meet-me--genes--germs--and-the-curious-forces-that-m/">Pleased to Meet Me: Genes, Germs, and the Curious Forces That Make Us Who We Are</a>.” I have a long-standing interest in how chemicals in food and the environment affect the body and mind. </p>
<p>When something seemingly harmless like licorice is implicated in a death, we are reminded of the <a href="https://doi.org/10.1093/toxsci/53.1.2">famous proclamation</a> by Swiss physician Paracelsus, considered the father of toxicology: “All things are poison, and nothing is without poison; the dosage alone makes it so a thing is not a poison.” </p>
<h2>Root of the problem</h2>
<p>The unfortunate man who succumbed to excessive black licorice consumption is not alone. There is a smattering of similar case reports in medical journals in which patients experienced a <a href="https://pubmed.ncbi.nlm.nih.gov/26380428/">sudden severe increase in blood pressure</a>, <a href="https://doi.org/10.5414/cn107011">muscle breakdown</a> or even death. </p>
<p>Adverse reactions are most frequently seen in people over the age of 40 who are eating far more black licorice than the average person. In addition, they are usually consuming the product for prolonged periods of time. In the 2020 case, the Massachusetts man had been eating a <a href="https://doi.org/10.1056/NEJMcpc2002420">bag and a half</a> of black licorice every day for three weeks.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Ilustration of a plant with round green leaves and pinkish blooms" src="https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=736&fit=crop&dpr=1 600w, https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=736&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=736&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=925&fit=crop&dpr=1 754w, https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=925&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/365280/original/file-20201023-18-upsl27.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=925&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>Glycyrrhiza glabra</em> is a species native to Eurasia and North Africa from which most confectionery licorice is produced.</span>
<span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/a/a4/Glycyrrhiza_glabra_-_K%C3%B6hler%E2%80%93s_Medizinal-Pflanzen-207.jpg">Franz Eugen Köhler/Köhler's Medizinal-Pflanzen via Wikimedia Commons</a></span>
</figcaption>
</figure>
<p>Licorice is a flowering plant native to parts of Europe and Asia. Its scientific name, <em>Glycyrrhiza</em>, is derived from the Greek words “glykos” (sweet) and “rhiza” (root). People have long used the aromatic and sweet extract from its root as an herbal remedy for a wide variety of health maladies, from heartburn and stomach issues to sore throats and cough. However, there is <a href="https://doi.org/10.1177%2F2042018812454322">insufficient evidence</a> that licorice is effective in treating any medical condition.</p>
<p>Glycyrrhizin, also called glycyrrhizic acid, is the chemical in black licorice that gives the candy its signature flavor, but it also leads to its toxic effects. </p>
<p>Glycyrrhizin mimics <a href="https://www.yourhormones.info/hormones/aldosterone/">aldosterone</a>, a hormone your adrenal glands make when your body needs to retain sodium and excrete potassium. <a href="https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Introductory_Biology_(CK-12)/02%3A_Cell_Biology/2.16%3A_Sodium-Potassium_Pump">Sodium and potassium</a> work together as a kind of cellular battery that drives communication between nerves and the contraction of muscles. Too much glycyrrhizin upsets the balance of these electrolytes, which can raise blood pressure and disturb the heart’s rhythm. <a href="https://doi.org/10.3390%2Fnu15183866">Other symptoms</a> of excessive licorice intake include swelling, muscle pain, numbness and headache. Examination of the man who died from consuming too much licorice revealed that he had <a href="https://doi.org/10.1056/NEJMcpc2002420">dangerously low levels of potassium</a>, consistent with glycyrrhizin toxicity.</p>
<p>It should be noted that a number of licorice-based foods do not contain real licorice but use a flavoring substitute called <a href="https://pubchem.ncbi.nlm.nih.gov/compound/Anise-Oil">anise oil</a>, which does not pose the dangers discussed here. In addition, despite its name, <a href="https://www.livestrong.com/article/537724-black-licorice-vs-red-licorice/">red licorice</a> rarely contains licorice extract. Instead, red licorice is infused with chemicals that impart its cherry or strawberry flavor.</p>
<p>Products that contain real licorice are usually labeled as such and list licorice extract or glycyrrhizic acid among the ingredients. Be advised that some products, such as black jelly beans or Good & Plenty, are mixtures of different candies that contain both anise oil and licorice extract.</p>
<figure class="align-center ">
<img alt="Close up of red licorice" src="https://images.theconversation.com/files/365294/original/file-20201023-23-1uee3ur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/365294/original/file-20201023-23-1uee3ur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=195&fit=crop&dpr=1 600w, https://images.theconversation.com/files/365294/original/file-20201023-23-1uee3ur.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=195&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/365294/original/file-20201023-23-1uee3ur.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=195&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/365294/original/file-20201023-23-1uee3ur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=245&fit=crop&dpr=1 754w, https://images.theconversation.com/files/365294/original/file-20201023-23-1uee3ur.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=245&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/365294/original/file-20201023-23-1uee3ur.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=245&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Red licorice is sickeningly sweet but safe to eat.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/wall-of-licorice-royalty-free-image/103742661?adppopup=true">Darren Boucher/Getty Images</a></span>
</figcaption>
</figure>
<h2>Hidden dangers increase risk</h2>
<p>Glycyrrhizin has the distinct licorice flavor and is <a href="https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=19&contentid=Licorice">50 times sweeter than sugar</a>. It has been used in other types of candy, soft drinks, tea, Belgian beers, throat lozenges and tobacco. The prevalence of glycyrrhizin can make it challenging to keep track of how much has been consumed, and a combination of these products could trigger adverse effects.</p>
<p>Some people take dietary or health supplements that already contain licorice, which increases the risk of toxic effects from eating black licorice candy. Certain medications such as <a href="https://doi.org/10.5414/cn107011">hydrochlorothiazide</a> are diuretics that cause increased urination, which can lower potassium levels in the body. Glycyrrhizin also lowers potassium levels, further disrupting the balance of electrolytes, which can produce muscle cramps and irregular heart rhythms.</p>
<p>People with certain <a href="https://doi.org/10.1177%2F2042018812454322">preexisting conditions</a> are more susceptible to black licorice overdose. For example, patients who already have low potassium levels, high blood pressure or heart arrhythmia are likely to have greater sensitivity to the effects of excessive licorice. Those with liver or kidney deficiencies will also retain glycyrrhizin in their bloodstream for longer periods, increasing their risk of experiencing adverse effects.</p>
<h2>Safely eating black licorice</h2>
<p>If you’re a fan of black licorice, there is no need to ban it from your pantry. Eaten in small quantities from time to time, licorice poses no significant threat to otherwise healthy adults and children. </p>
<p>But it is advisable to monitor your intake. A 2024 study conducted in Sweden found that daily ingestion of 100 mg of licorice, which is <a href="https://apps.who.int/food-additives-contaminants-jecfa-database/Home/Chemical/4366">considered a safe amount</a>, for two weeks was <a href="http://dx.doi.org/10.1016/j.ajcnut.2024.01.011">sufficient to raise blood pressure</a> by an average of 3.1 mm Hg. A quarter of the participants also had elevated blood levels of a protein that is made when the heart is working harder.</p>
<p>Be sure to remind your kids that candy is a “<a href="https://www.preventivehealth.sa.gov.au/healthy-living/being-active-healthy/eating-well/how-to-eat-less-sometimes-foods">sometimes food</a>,” especially black licorice. The U.S. Food and Drug Administration had <a href="https://wayback.archive-it.org/7993/20171031104524mp_/https:/www.fda.gov/ForConsumers/ConsumerUpdates/ucm277152.htm">issued warnings</a> about the rare but serious effects of too much black licorice, advising that people avoid eating more than 2 ounces of black licorice a day for two weeks or longer. The agency advises that if you have been eating a lot of black licorice and experience an irregular heart rhythm or muscle weakness, stop eating it immediately and contact your health care provider.</p>
<p>Some scientists have further cautioned against the routine use of licorice in the form of a dietary supplement or tea for its alleged health benefits, including the treatment of cough <a href="https://doi.org/10.1002/emp2.12411">associated with COVID-19</a> or other respiratory infections. A review article from 2012 warned that “the daily consumption of licorice is <a href="https://doi.org/10.1177/2042018812454322">never justified</a> because its benefits are minor compared to the adverse outcomes of chronic consumption.”</p>
<p><em>This article, originally published Oct. 26, 2020, has been updated to include results from a 2024 study.</em></p><img src="https://counter.theconversation.com/content/147001/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bill Sullivan does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Who knew that black licorice could be dangerous? A scientist and new research explains when this treat becomes a threat.Bill Sullivan, Professor of Pharmacology and Toxicology, Indiana UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1468252020-10-15T19:03:06Z2020-10-15T19:03:06ZExposure to man-made chemicals influences genes controlling aging, immune system and metabolism<figure><img src="https://images.theconversation.com/files/363279/original/file-20201013-13-pj36wo.jpg?ixlib=rb-1.1.0&rect=92%2C0%2C5515%2C3640&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Most genes in the human body can be disrupted by man-made chemicals.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/smoke-coming-out-of-power-plant-china-royalty-free-image/977807238?adppopup=true">Göran Andersson/Getty Images</a></span></figcaption></figure><p>Today humans are exposed to thousands of man-made chemicals. Yet the effects on people’s health are still not fully understood.</p>
<p>In 2020 the number of registered chemicals reached <a href="https://www.cas.org/support/documentation/chemical-substances">167 million</a>. Every day people are exposed to them through food, water, contaminated air, drugs, cosmetics and other man-made substances. Less than <a href="https://www.chemistryworld.com/news/us-agencies-test-less-than-1-of-chemicals-/9220.article">1% of these chemicals were tested for toxicity</a>, and those that were tested demonstrate ability to disrupt almost every biological process in our body. Can we infer how cumulative exposures shape our health?</p>
<p><a href="https://blogs.umass.edu/asuvorov/">I am an environmental toxicologist</a> studying effects of man-made chemicals on our health. I decided to develop <a href="https://doi.org/10.1016/j.chemosphere.2020.128362">a computational approach</a> to objectively compare sensitivity of all genes to all chemicals and identify the most vulnerable biological processes.</p>
<h2>Unbiased approach</h2>
<p><a href="https://doi.org/10.1016/j.chemosphere.2020.128362">For our study</a>, my research colleagues and I used data from the <a href="http://ctdbase.org">Comparative Toxicogenomic Database</a>. The Comparative Toxicogenomic Database collects information from thousands of published studies on how chemicals change the activity of genes. Genes are sections of DNA that encode proteins which perform a broad range of functions in cells, from building tissues to metabolizing nutrients. When chemicals affect genes, that results in increased or decreased production of proteins.</p>
<p>Modern methods of molecular biology can detect changes in activity of all genes in the genome in response to a chemical insult. I developed an approach that overlays lists of altered genes from different studies to calculate how many times each gene was affected. The resulting numbers reflect sensitivities of genes to chemicals generally. </p>
<p>Using 2,169 studies on mice, rats, humans and their cells, my research group ranked the sensitivity of 17,338 genes to chemical exposures. These studies tested the impact of 1,239 diverse chemicals ranging from prescription drugs to environmental pollutants. </p>
<p>At the next step we ran tests to ensure that this sample of over 1,000 chemicals was large enough to reliably represent all classes of man-made chemicals people are exposed to. To do so, we measured sensitivity of genes for one half of this list and then for another to test if even a smaller number of chemicals can reliably identify sensitive genes. The results were encouraging – the values of gene sensitivities were almost identical in the two trials. </p>
<h2>Cellular defense system responds to chemicals</h2>
<p>Our cells are not completely helpless when exposed to chemical insults. In fact, they <a href="https://doi.org/10.1038/sj.onc.1208615">possess strategies for dealing with stress and damage induced by chemicals</a>. Our data confirm that these safeguards become active in response to exposures. </p>
<p>This line of defense includes enzymes that eliminate toxic chemicals, alleviate oxidative stress (the accumulation of reactive radicals in cells), repair damaged DNA and proteins, and identify highly damaged cells to trigger their death and prevent them from turning cancerous. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=405&fit=crop&dpr=1 600w, https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=405&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=405&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=508&fit=crop&dpr=1 754w, https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=508&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/363283/original/file-20201013-21-3nrd7q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=508&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Could exposure to man-made chemicals be boosting obesity rates around the world?</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/midsection-of-overweight-boy-measuring-waist-with-royalty-free-image/1192272111?adppopup=true">Chutima Sonma / EyeEm/Getty Images</a></span>
</figcaption>
</figure>
<h2>Metabolism of lipids and carbohydrates is vulnerable</h2>
<p>Surprisingly, we found that molecular networks involved in the regulation of cellular metabolism are most sensitive to chemical exposures. One of them is <a href="https://doi.org/10.1146/annurev.med.53.082901.104018">PPAR signaling</a>. PPARs are a group of proteins that regulate energy balance and metabolism of lipids and glucose.</p>
<p>Rises or falls in PPARs activity contribute to <a href="https://doi.org/10.1038/cr.2010.13">obesity, metabolic syndrome, diabetes and fatty liver disease</a>. The ability of some <a href="https://doi.org/10.1016/j.tiv.2019.104700;%20https://doi.org/10.1038/ijo.2008.207">environmental chemicals</a> to affect PPARs was shown before. However, we didn’t expect to see sensitivity of PPARs to a very broad range of compounds. </p>
<p>We also discovered that genes involved in the development of pancreatic beta cells, which secrete insulin and play a key role in glucose metabolism, are suppressed by a majority of chemicals in our list. Dysfunction of beta cells results in diabetes. Thus, cumulative chemical exposures may be a significant risk factor for diabetes.</p>
<p>Today an epidemic of metabolic disease is a major public health issue. The prevalence of <a href="https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight">obesity nearly tripled between 1975 and 2016</a>. Approximately <a href="https://doi.org/10.1016/S2213-8587(14)70161-5">40% of Americans will develop Type 2 diabetes during their lives</a>, and <a href="https://doi.org/10.1152/ajpendo.00064.2004">33%-88% have fatty liver</a>. <a href="https://doi.org/10.1111/j.1365-2605.2007.00858.x;%20https://doi.org/10.1210/jc.2014-4326">Connection between exposures and metabolic diseases was shown before for some chemicals with endocrine disruptive properties</a>. However, the role of a broadest range of man-made chemicals in this epidemic was not recognized before but can be significant. </p>
<h2>Growth, aging and the immune system</h2>
<p>Two hormones involved in growth – growth hormone (GH) and insulin-like growth factor (IGF1) – are also affected by exposure to chemicals. </p>
<p>IGF1 is a hormone <a href="https://doi.org/10.1038/ncpendmet0427">secreted mostly by the liver</a>. It is recognized as a major regulator of <a href="https://doi.org/10.1098/rspb.2013.2458">body growth</a>. Additionally, multiple mouse experiments show that decreased GH-IGF1 signaling <a href="https://doi.org/10.5483/BMBRep.2019.52.1.299">results in longer lifespan</a>. This pathway also determines if cells will <a href="https://doi.org/10.1016/j.cell.2012.03.017">use energy to build new molecules the body needs</a>, or if they will break down existing molecules to release energy for the organism to use. The ability of chemicals to affect this central regulator of growth and aging is a novel finding. What health problems may be due to the sensitivity of GH-IGF1 is yet to be uncovered. </p>
<p>Our analysis indicates that genes that control the immune response are also highly sensitive to chemicals.</p>
<p>Two major outcomes of a dysfunctional immune system are allergy and autoimmunity. Prevalence for both conditions follows upward trends. Food allergies increased from <a href="https://www.cdc.gov/nchs/data/databriefs/db121.pdf">3.4% to 5.1% between 1997 and 2011 among children in the U.S.</a> Skin allergies increased from <a href="https://www.cdc.gov/nchs/data/databriefs/db121.pdf">7.4% to 12.5% during the same period</a>. Another study showed a <a href="https://doi.org/10.1002/art.41214">5% increase in blood marker of autoimmune disease</a> in Americans during the period 1988-2012.</p>
<h2>All molecular pathways are sensitive to chemicals</h2>
<p>Overall we found that almost every known pathway may be affected by chemicals. That finding has significant implications for regulatory toxicology.</p>
<p>With ever-increasing numbers of man-made chemicals, <a href="https://doi.org/10.1289/ehp.118-a172a">society needs to develop</a> <a href="https://doi.org/10.1016/j.tox.2013.08.011">rapid and cost-efficient methods</a> of toxicity testing. </p>
<p>[<em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>.]</p>
<p>One important question that remains unanswered is what pathways should be covered by testing to ensure that regulators do not approve chemicals that harm or disrupt critical molecular circuits. Our data suggests that we need to develop tests that cover every known molecular pathway without exception.</p>
<p>Our study outlines new priorities for toxicological research, including the role of chemical exposures for metabolic health, immune system, development and aging.</p><img src="https://counter.theconversation.com/content/146825/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alexander Suvorov receives funding from the US NIH. </span></em></p>Man-made chemical disrupt the activities of most human genes. What effect does this have on human health and how should regulators respond?Alexander Suvorov, Assistant Professor, UMass AmherstLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1455742020-09-04T11:31:21Z2020-09-04T11:31:21ZNovichok: how are victims surviving poisoning?<p>Russian opposition leader Alexei Navalny is <a href="https://www.theguardian.com/world/2020/sep/03/alexei-navalny-faces-long-and-uncertain-road-to-recovery">likely to survive</a> a suspected poisoning with the <a href="https://theconversation.com/nerve-agents-what-are-they-and-how-do-they-work-93079">nerve agent Novichok</a>, according to the hospital treating him. There have now been at least six known cases of serious Novichok poisoning in the past two years. But only one victim <a href="https://www.bbc.co.uk/news/uk-45000472">tragically died from it</a>.</p>
<p>Why is that? Is the substance less lethal than previously thought? Or could it be that the stockpile of the nerve agent is degrading?</p>
<p>Nerve agents were discovered through pesticide research. They belong to a group of substances known as <a href="https://cot.food.gov.uk/sites/default/files/cot/opchap.pdf">organophosphorus chemicals</a>, or “OPs” for short. There are literally thousands of OP substances, many of which can damage the body by inhibiting a family of enzymes known as “<a href="https://pubmed.ncbi.nlm.nih.gov/22286807/">cholinesterases</a>” that are critical to regulating the activity of the central nervous system in animals.</p>
<p>OP pesticides are much less toxic to humans than nerve agents because they have been designed to specifically inhibit insect cholinesterases. In contrast, nerve agents target human cholinesterases.</p>
<p>By disrupting the nervous system, Novichok and other nerve agents can kill people through asphyxiation or cardiac arrest. We know they are deadly. The nerve agent Sarin caused multiple casualties in 1995 <a href="https://time.com/3742241/tokyo-subway-attack-1995/">when it was released</a> in the Tokyo subway. </p>
<p>The nerve agent VX is thought to have <a href="https://www.theguardian.com/world/2019/apr/01/how-north-korea-got-away-with-the-assassination-of-kim-jong-nam">killed Kim Jong-nam</a>, the half brother of North Korea’s leader Kim Jong-un, in just 20 minutes after it was allegedly smeared across his face. But all types of nerve agent poisoning can be treated with standard antidotes such as <a href="https://www.drugbank.ca/drugs/DB00572">atropine</a> and <a href="https://www.nhs.uk/medicines/diazepam/">diazepam</a>. </p>
<p>Little is known about the types of Novichok that have been synthesised or deployed in assassination attempts, other than that they tend to be liquids or powders.</p>
<h2>The dose makes the poison</h2>
<p>One of the fundamental principles of toxicology was <a href="https://collection.sciencemuseumgroup.org.uk/people/cp72721/paracelsus">first proposed</a> by a 16th century alchemist, known as Paracelsus, who is often credited with the statement “<em>sola dosis facit venenum</em>”, or “the dose makes the poison”. It means that all substances are capable of being toxic if administered in a sufficient dose. This applies to normally innocuous chemicals such as water, as well as highly toxic materials such as nerve agents. </p>
<p>So have the recent Novichok victims somehow got smaller doses than intended? In the case of the poisoning of <a href="https://www.bbc.co.uk/news/uk-43643025">Sergei and Yulia Skripal</a> in Salisbury, UK, in 2018, it appears that the poison was initially applied to <a href="https://www.bbc.co.uk/news/uk-43577987">a door knob</a>. </p>
<p>While the applied dose may have been quite large, possibly equating to several thousand lethal doses, the amount transferred to their skin would have been a fraction of that. The palm of the hand is also one of the least permeable areas of the human body, which would reduce the rate of absorption into the body.</p>
<p>Subsequent contact with other surfaces through normal daily activities would be expected to further reduce the dose on the victims’ hands. This means that the net dose absorbed by the skin would have been relatively small in comparison to the original amount. </p>
<p>In the case of the Skripals, this was still sufficient to cause life-threatening toxicity after a delay of several hours. The fact that they were quickly given appropriate antidotes and supportive therapies was instrumental in their survival.</p>
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<img alt="" src="https://images.theconversation.com/files/227219/original/file-20180711-27030-1gf3i9c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/227219/original/file-20180711-27030-1gf3i9c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/227219/original/file-20180711-27030-1gf3i9c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/227219/original/file-20180711-27030-1gf3i9c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/227219/original/file-20180711-27030-1gf3i9c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/227219/original/file-20180711-27030-1gf3i9c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/227219/original/file-20180711-27030-1gf3i9c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Police searching Salisbury and Amesbury after poisoning attack.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Britain-Poisoning-Probe/8f963000907944fc8462ff2246b871e0/16/0">Matt Dunham/AP Photo</a></span>
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<p>Two police officers <a href="https://www.bbc.co.uk/news/uk-england-wiltshire-49361327">were subsequently also poisoned</a> with the substance when searching Skripals’ home – and both survived. It is possible that they received an even lower dose of Novichok than the Skripals.</p>
<p>Soon after the incident, two more people were poisoned in nearby Amesbury. Tragically, one victim, Dawn Sturgess, died. She had unknowingly <a href="https://www.businessinsider.com/novichok-dawn-sturgess-reportedly-sprayed-poison-on-wrists-like-perfume-2018-7?r=US&IR=T">sprayed Novichok directly onto her wrist</a> from a perfume bottle her partner had found nearby. </p>
<p>This would undoubtedly have resulted in a much higher dose than the Skripals received and was applied to a thinner, more permeable area of skin. The fact that the onset of poisoning was much faster (minutes) than in the case of the Skripals tends to support this idea. </p>
<p>Sadly, prompt medical treatment was unable to prevent her death. Antidotes can be effective against several multiples of a lethal dose. For example, military antidotes are generally designed to allow survival from at least five lethal doses of a nerve agent. However, no antidote will be effective against a massive dose. </p>
<p>Strurgess’ partner, Charlie Rowley, reportedly spilled some of the contents of the perfume bottle onto his hands, but <a href="https://www.dailymail.co.uk/news/article-5987495/First-pictures-novichok-victim-Charlie-Rowley-release-hospital.html#:%7E:text=He%20was%20so%20ill%20when,why%20he%20believes%20he%20survived">immediately washed off</a> the oily residue. Immediate decontamination is known to be a highly effective practice against nerve agents and is the recommended initial treatment strategy for chemically contaminated casualties in the <a href="https://emj.bmj.com/content/36/2/117">UK</a> and <a href="https://www.medicalcountermeasures.gov/barda/cbrn/prism/">USA</a>. It is likely that this action saved the life of Rowley.</p>
<p>In the case of Navalny, it has been reported that he was poisoned through a <a href="https://www.theguardian.com/world/2020/aug/20/a-cup-of-tea-then-screams-of-agony-how-alexei-navalny-was-left-fighting-for-his-life">contaminated cup of tea</a>. As the amount added to the beverage is likely to have been multiples of a lethal dose, how did he survive?</p>
<p>The exact details of the incident are not available, but a variety of factors may have influenced the dose he absorbed. For example, he may just have had just a few sips rather than the whole cup. Initial reports indicate that Navalny also vomited. We also don’t know if the Novichok was adequately dissolved in the tea. These factors may all have contributed to lowering the dose.</p>
<p>The inherent toxicity of nerve agents is a clear attraction to would-be assassins, as are other poisons such as arsenic, cyanide and ricin. However, the practical difficulties in disseminating any type of poison will introduce a wide margin of error in dosing. </p>
<p>Current information suggests that Novichok agents are chemically stable and are manufactured to high purity <a href="https://www.theguardian.com/world/2018/mar/14/nerve-agent-novichok-produced-russia-site-expert">in specialist production facilities</a>. Therefore, surviving exposure is unlikely to be due to “poor quality” Novichok. The substance is no doubt lethal and has resulted in the death of innocent people as well as the intended victims.</p><img src="https://counter.theconversation.com/content/145574/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This article is wholly based on information available in the public domain. The opinions stated are those of the author and do not reflect the views, opinions or policies of any government department.
Robert Chilcott has previously received funding to investigate mass casualty decontamination protocols from the UK's Home Office and Department of Health, the European Union, and the US Biomedical Advanced Research and Development Authority (BARDA). </span></em></p>It’s all about the dose.Robert Chilcott, Professor, Centre for Research into Topical Drug Delivery and Toxicology, University of HertfordshireLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1439792020-08-05T04:46:47Z2020-08-05T04:46:47ZWhat is ammonium nitrate, the chemical that exploded in Beirut?<p>The Lebanese capital Beirut <a href="https://www.theguardian.com/world/live/2020/aug/04/beirut-explosion-huge-blast-port-lebanon-capital">was rocked</a> on Tuesday evening local time by an explosion that has killed at least 78 people and injured thousands more.</p>
<p>The country’s prime minister Hassan Diab said the blast was caused by around 2,700 tonnes of ammonium nitrate stored near the city’s cargo port. Video footage appears to show a <a href="https://www.npr.org/2020/08/04/898969935/massive-explosion-rocks-beirut-damaging-buildings-and-shattering-windows">fire</a> burning nearby before the blast. </p>
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<p>Ammonium nitrate has the chemical formula NH₄NO₃. Produced as small porous pellets, or “prills”, it’s one of the world’s most widely used fertilisers. </p>
<p>It is also the main component in many types of mining explosives, where it’s mixed with fuel oil and detonated by an explosive charge.</p>
<p>For an industrial ammonium nitrate disaster to occur, a lot needs to go wrong. Tragically, this seems to have been the case in Beirut. </p>
<h2>What could have caused the explosion?</h2>
<p>Ammonium nitrate does not burn on its own. </p>
<p>Instead, it acts as a source of oxygen that can accelerate the <a href="https://www.bbc.co.uk/bitesize/topics/zypsgk7/articles/zcwxcj6">combustion</a> (burning) of other materials. </p>
<p>For combustion to occur, oxygen must be present. Ammonium nitrate prills provide a much more concentrated supply of oxygen than the air around us. This is why it is effective in mining explosives, where it’s mixed with oil and other fuels.</p>
<p>At high enough temperatures, however, ammonium nitrate can violently decompose on its own. This process creates gases including nitrogen oxides and water vapour. It is this rapid release of gases that causes an explosion. </p>
<p>Ammonium nitrate decomposition can be set off if an explosion occurs where it’s stored, if there is an intense fire nearby. The latter is what happened in the 2015 <a href="https://www.bbc.com/news/world-asia-china-37927158">Tianjin explosion</a>, which killed 173 people after flammable chemicals and ammonium nitrate were stored together at a chemicals factory in eastern China.</p>
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Read more:
<a href="https://theconversation.com/explainer-how-dangerous-is-the-sodium-cyanide-found-at-tianjin-explosion-site-46229">Explainer: how dangerous is the sodium cyanide found at Tianjin explosion site?</a>
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<p>While we don’t know for sure what caused the explosion in Beirut, footage of the incident indicates it may have been set off by a fire – visible in a section of the city’s port area before the explosion happened. </p>
<p>It’s relatively difficult for a fire to trigger an ammonium nitrate explosion. The fire would need to be sustained and confined within the same area as the ammonium nitrate prills. </p>
<p>Also, the prills themselves are not fuel for the fire, so they would need to be contaminated with, or packaged in, some other combustible material.</p>
<h2>Residents’ health at risk</h2>
<p>In Beirut, it has been reported 2,700 tonnes of ammonium nitrate were <a href="https://www.theguardian.com/world/live/2020/aug/04/beirut-explosion-huge-blast-port-lebanon-capital">stored in a warehouse</a> for six years without proper safety controls.</p>
<p>This will almost certainly have contributed to the tragic circumstances that resulted in a commonplace industrial fire causing such a devastating explosion.</p>
<p>An ammonium nitrate explosion produces massive amounts of <a href="https://www.abc.net.au/news/2020-06-15/bright-orange-mine-blast-concerns-residents/12332224">nitrogen oxides</a>. Nitrogen dioxide (NO₂) is a red, bad-smelling <a href="https://www.abc.net.au/news/2020-06-15/bright-orange-mine-blast-concerns-residents/12332224">gas</a>. Images from Beirut reveal a distinct reddish colour to the plume of gases from the blast. </p>
<p>Nitrogen oxides are commonly present in urban air pollution, and can irritate the respiratory system. Elevated levels of these pollutants are particularly concerning for people with respiratory conditions.</p>
<p>The fumes in Beirut will present a health risk to residents until they naturally dissipate, which could take several days depending on the local weather. </p>
<h2>An important reminder</h2>
<p>Here in Australia, we produce and import large amounts of ammonium nitrate, mostly for use in mining. It is made by combining <a href="https://www.britannica.com/science/ammonia">ammonia</a> gas with liquid nitric acid, which itself is made from ammonia.</p>
<p>Ammonium nitrate is classified as <a href="http://www.dmp.wa.gov.au/Dangerous-Goods/What-is-a-dangerous-good-4411.aspx">dangerous goods</a> and all aspects of its use are tightly regulated. For decades, Australia has produced, stored and used ammonium nitrate without a <a href="https://www.abc.net.au/news/2014-09-07/ammonium-nitrate-truck-explosion-site/5725904?nw=0"><em>major</em></a> incident. </p>
<p>The explosion in Beirut shows us just how important these regulations are.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/75-years-after-hiroshima-and-nagasaki-the-vatican-is-providing-moral-guidance-on-nuclear-weapons-140615">75 years after Hiroshima and Nagasaki, the Vatican is providing moral guidance on nuclear weapons</a>
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<img src="https://counter.theconversation.com/content/143979/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gabriel da Silva does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>For combustion to occur, oxygen must be present. Ammonium nitrate prills provide a much more concentrated supply of oxygen than the air around us.Gabriel da Silva, Associate Professor of Chemical Engineering, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1112432019-03-01T20:13:45Z2019-03-01T20:13:45ZEPA’s plan to regulate chemical contaminants in drinking water is a drop in the bucket<figure><img src="https://images.theconversation.com/files/261713/original/file-20190301-110150-b7wzv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Hoosick Fall, N.Y. is one of many U.S. communities whose drinking water has been contaminated with PFOA or PFOS.</span> <span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Village-Water-Chemical/1f0f5817921d4b6789be6c2b9a41da43/22/0">AP Photo/Mike Groll, File</a></span></figcaption></figure><p>After more than a year of community meetings and deliberations, the U.S. Environmental Protection Agency announced in February 2019 that it would <a href="https://www.epa.gov/pfas">begin the process of regulating</a> two drinking water contaminants, seeking to stem a <a href="https://www.washingtonpost.com/national/health-science/not-a-problem-you-can-run-away-from-communities-confront-the-threat-of-unregulated-chemicals-in-their-drinking-water/2019/01/01/a9be8f72-dd4b-11e8-b732-3c72cbf131f2_story.html?utm_term=.a20c31739d0d">growing national public health crisis</a>. If EPA follows through, this would be the first time in nearly 20 years that it has set an enforceable standard for a new chemical contaminant under the <a href="https://www.epa.gov/sdwa">Safe Drinking Water Act</a>.</p>
<p>The chemicals at issue, PFOA and PFOS, have contaminated drinking water supplies across the country affecting millions of Americans. They belong to a class of synthetic chemicals called PFAS, or per- and polyfluoroalkyl substances, that are <a href="https://www.epa.gov/chemical-research/research-and-polyfluoroalkyl-substances-pfas">widely used</a> in products including firefighting foams, waterproof apparel, stain-resistant furniture, <a href="https://doi.org/10.1021/acs.estlett.6b00435">food packaging</a> and even <a href="https://doi.org/10.1038/s41370-018-0109-y">dental floss</a>.</p>
<p>These chemicals have been linked with <a href="https://www.atsdr.cdc.gov/toxprofiles/tp200.pdf">numerous health problems</a>, including cancers, thyroid disease, high cholesterol, low birth weight and effects on the immune system. Studies show exposure to PFAS in children can <a href="http://dx.doi.org/10.1001/jama.2011.2034">dampen the effectiveness of vaccines</a> – a topic my colleagues and I are currently investigating as part of a project called <a href="https://silentspring.org/press-releases/scientists-examine-health-impacts-children-exposed-contaminated-drinking-water">PFAS-REACH</a>. In laboratory studies, low levels of PFAS can alter mammary gland development, which could have implications for <a href="http://dx.doi.org/10.1289/ehp.1002864">increasing breast cancer susceptibility</a> later in life. </p>
<p>What’s more, PFAS are highly persistent. Once released into the environment, they don’t break down – a fact that has led many to dub these substances “forever chemicals.”</p>
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<a href="https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=311&fit=crop&dpr=1 600w, https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=311&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=311&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=391&fit=crop&dpr=1 754w, https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=391&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/261448/original/file-20190228-106353-1dbzozd.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=391&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A 2016 study found that drinking water supplies for 6 million U.S. residents exceeded EPA’s lifetime health advisory levels for PFOS and PFOA.</span>
<span class="attribution"><a class="source" href="https://pubs.acs.org/doi/10.1021/acs.estlett.6b00260">Hu et al., 2016.</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<h2>A persistent problem</h2>
<p>PFAS have been used for decades, but only in the last few years have we begun to grasp the full extent of contamination. A 2016 study reported that <a href="http://dx.doi.org/10.1021/acs.estlett.6b00260">over 16 million Americans</a> are exposed to these contaminants in drinking water, and a more recent estimate put that number at <a href="https://www.ewg.org/research/report-110-million-americans-could-have-pfas-contaminated-drinking-water">110 million</a>. </p>
<p>PFAS find their way into water supplies from military fire training areas and airports, as well as industrial sites and wastewater treatment plants. For instance, in 2010 my colleagues and I at the nonprofit <a href="https://silentspring.org/">Silent Spring Institute</a>, which studies links between environmental chemicals and women’s health, first detected PFAS in <a href="https://doi.org/10.1016/j.scitotenv.2013.08.067">public and private drinking water wells</a> on Cape Cod, Massachusetts. The Department of Defense has identified approximately <a href="https://www.gao.gov/products/GAO-18-700T">400 current or former military sites</a> with known or suspected contamination, stemming mostly from use of firefighting foams. </p>
<p>Today there are more than <a href="http://www.oecd.org/officialdocuments/publicdisplaydocumentpdf/?cote=ENV-JM-MONO(2018)7&doclanguage=en">4,700 PFAS substances in use</a>. All are chemically similar and highly persistent. The United States phased PFOS out of products in 2000 and PFOA in 2006, but they are still turning up widely in drinking water, which is why states want EPA to set standards specifying what levels of exposure are safe. Meanwhile, studies suggest that some newer PFAS chemicals have <a href="http://dx.doi.org/10.1016/j.envint.2018.01.011">similar health effects</a>, and most <a href="https://www2.mst.dk/Udgiv/publications/2015/05/978-87-93352-15-5.pdf">have not been studied</a> at all. </p>
<p>Scientists are working hard to better understand these chemicals in order to mitigate the public’s exposure. For example, researchers at the <a href="https://web.uri.edu/steep/">STEEP Superfund Research Program</a>, a multi-institutional effort which I am a part of, are investigating how these chemicals move through the environment, their chemical characteristics, how they accumulate in our bodies, and their impacts on our health.</p>
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<figcaption><span class="caption">PFAS contamination is a problem near many military bases, which use the chemicals in firefighting foams.</span></figcaption>
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<h2>A shifting landscape</h2>
<p>EPA has been considering regulating PFOS and PFOA in drinking water since 2009. The agency’s recent announcement is a step in the right direction, but still only addresses these two chemicals in drinking water and any new federal standard won’t be fully implemented for years. </p>
<p>Earlier this year my colleagues and I published an analysis in which we showed <a href="https://doi.org/10.1038/s41370-018-0099-9">wide variation</a> in the way state and federal regulators manage these contaminants in drinking water. We found that seven states have their own guideline levels for PFOA and PFOS. Of these, Vermont, Minnesota and New Jersey have adopted levels that are more stringent than EPA’s current non-enforceable levels. </p>
<p>More recently, New Hampshire, New York and California have also proposed guideline levels lower than EPA’s. The day after EPA announced its plan, Pennsylvania officials announced they would create their own standards, citing concerns about EPA’s sluggish efforts to address the issue. </p>
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<p>Meanwhile, some states are developing their own guidelines covering additional PFAS chemicals. For instance, Minnesota has included in its guidelines a chemical called PFBS, which is used in Scotchgard. North Carolina regulators are focusing their efforts on a substitute called GenX that seeped into local water supplies from a plant upstream and has been detected in their air and soil.</p>
<p>A key question now is how EPA’s drinking water standard for PFOA and PFOS will compare with what states are doing. Will the agency consider the full body of scientific evidence on health risks associated with exposure to this class of chemicals when setting a “safe” limit in drinking water? Will it consider effects on sensitive populations, such as pregnant women and children? Although the science is still evolving, one thing is clear: The more we learn about these chemicals, the more we see health effects at <a href="https://doi.org/10.1186/1476-069X-12-35">lower and lower levels</a>. </p>
<p>It is important to give states latitude to adopt more stringent approaches than those set by EPA, and a lot can be learned from how states set guidelines. However, the emerging regulatory patchwork raises concerns that some Americans are not adequately protected. Some states have the resources and technical know-how to conduct their own risk assessments, but others may lack the funding and expertise. </p>
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<p>Political and social factors, as well as pressure from industry, can lead to wide disparities in exposure, with some communities protected and others left vulnerable. A federal standard would ensure that everyone is protected, regardless of whether their states have the will and the resources to develop their own standards.</p>
<h2>It’s all in the family</h2>
<p>EPA’s plan includes other steps that sound promising, such as listing PFOS and PFOA as “hazardous substances” under the <a href="https://www.epa.gov/superfund/what-superfund">Superfund law</a> to establish liability for contamination and support cleanup, enhanced monitoring in drinking water, and better reporting of releases from industry. But the plan largely focuses on addressing problems at existing contaminated sites, not on keeping these chemicals out of water supplies and the environment.</p>
<p>Conducting risk assessments on individual PFAS compounds one at a time is impractical. As a result, many advocacy groups and scientists – including my colleagues at the <a href="https://greensciencepolicy.org/">Green Science Policy Institute</a> – are calling for these chemicals to be <a href="http://dx.doi.org/10.1289/ehp.1509934">regulated as a class</a>.</p>
<p>Under the <a href="https://www.epa.gov/laws-regulations/summary-toxic-substances-control-act">Toxic Substances Control Act</a>, EPA has authority to restrict approval of new toxic chemicals. But in reality, new ones are approved all the time <a href="https://theintercept.com/2018/10/25/epa-pfoa-pfas-pfos-chemicals/">without thorough evaluations</a>. Given concerns about the extreme persistence and mobility of PFAS compounds, in my view it makes good sense to restrict this entire class of chemicals. </p>
<p>There are precedents for such action. In 1979 the United States <a href="https://archive.epa.gov/epa/aboutepa/epa-bans-pcb-manufacture-phases-out-uses.html">banned PCBs</a> after these persistent and toxic chemicals became widespread in the environment. The global community banned chlorofluorocarbons in 1996 when scientists learned that they <a href="https://theconversation.com/is-earths-ozone-layer-still-at-risk-5-questions-answered-91470">damage Earth’s stratospheric ozone layer</a>. And in 2017 the U.S. Consumer Product Safety Commission voted to ban <a href="https://silentspring.org/blog/victory-federal-panel-takes-action-class-flame-retardants">an entire class of toxic flame retardants</a> from consumer products. </p>
<p>There is ample evidence for treating PFAS the same way. The question is whether federal regulators have the will.</p><img src="https://counter.theconversation.com/content/111243/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laurel Schaider receives funding from the National Institute of Environmental Health Sciences, the National Science Foundation, and the Casey & Family Foundation. She is a research scientist in environmental chemistry and engineering at Silent Spring Institute in Newton, Mass., where she leads the Institute's drinking water quality research program.</span></em></p>EPA is moving to regulate two chemicals from a group called PFAS that are contaminating drinking water. A public health expert explains why the agency should take much broader action.Laurel Schaider, Visiting Scientist, Harvard T.H. Chan School of Public Health, Harvard UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1055592018-10-26T10:46:27Z2018-10-26T10:46:27ZRoundup weed killer lawsuit hits a snag, but Monsanto is not off the hook<figure><img src="https://images.theconversation.com/files/242360/original/file-20181025-71020-e1khvm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Bottles of Monsanto's Roundup weed killer in the United Kingdom, relabelled by activists to highlight the World Health Organization's judgment that its main ingredient is a probable carcinogen.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/GMTxeG">Global Justice Now</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>On Aug. 10, 2018, a San Francisco jury handed down a US$289 million award to Dewayne Johnson, a groundskeeper who is dying of non-Hodgkin lymphoma. Johnson sued Monsanto, the maker of the weed killer Roundup, claiming that glyphosate – the active ingredient in Roundup – caused his cancer. The jury awarded Johnson $39 million in compensatory damages and $250 million dollars in punitive damages. </p>
<p>Now, in response to a request from Monsanto for a new trial, Superior Court Judge Suzanne Bolanos has <a href="https://www.cnn.com/2018/10/22/health/monsanto-judge-final-ruling-dewayne-johnson-case/index.html">partially overturned</a> that verdict. Judge Bolanos let stand the jury’s finding that Roundup caused Johnson’s cancer, but decided that the punitive damage award was too high, and offered Johnson two alternatives: accept $39 million in punitive damages ($78 million in total), or submit to a new trial on the punitive damages. The compensatory damages of $39 million would remain intact either way.</p>
<p>This new twist in the case highlights key questions in tort litigation: What is the meaning of “proof of causation,” and what constitutes fair compensation once “cause” has been “proven”? My field, cancer epidemiology, has developed ways to think about causation, but we still <a href="https://www.healthknowledge.org.uk/e-learning/epidemiology/practitioners/causation-epidemiology-association-causation">struggle with defining it</a> for individual patients. Whenever epidemiology is used in court, an added layer of complexity comes from issues of human suffering and fairness to the individual plaintiff.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/x000RkDAIkc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In 2017, 22 women and their families were awarded $4.7 billion in a lawsuit claiming that talcum powder made by Johnson & Johnson contained asbestos and gave the women ovarian cancer.</span></figcaption>
</figure>
<h2>A cascade of syllogisms</h2>
<p>There are several crucial steps in product liability litigation, each of which depends on a <a href="https://en.wikipedia.org/wiki/Syllogism">syllogism</a>. If a person is injured, then there must be a cause. If the cause was a company’s product, then that company should pay compensation. If the company knew, or had a good reason to suspect, that the product was dangerous, then the company should be punished and required to pay punitive monetary damages.</p>
<p>Glyphosate was classified as a probable human carcinogen in 2015 by the <a href="https://www.iarc.fr/">International Agency for Research on Cancer</a> (IARC), which is part of the <a href="http://www.who.int/">World Health Organization</a>. That classification was one cornerstone of Johnson’s lawsuit. The other cornerstone was a series of <a href="https://www.nytimes.com/2017/08/01/business/monsantos-sway-over-research-is-seen-in-disclosed-emails.html">internal Monsanto documents</a> which seemingly implied that the company knew or suspected that glyphosate was dangerous.</p>
<p>The jury was persuaded that Johnson’s cancer was caused by Roundup, and that Monsanto had known it was dangerous for a long time. Each of these decisions, of course, was a matter of opinion. That’s how the legal system works to <a href="https://theconversation.com/does-monsantos-roundup-cause-cancer-trial-highlights-the-difficulty-of-proving-a-link-100875">“prove” cause and effect</a>. Some jurors felt so strongly about their verdict that they <a href="https://abcnews.go.com/US/wireStory/judge-upholds-monsanto-verdict-cuts-award-78-million-58675789">wrote to Judge Bolanos</a> urging her not to overturn it.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=410&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=410&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=410&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=515&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=515&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242369/original/file-20181025-71038-m3h3ib.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=515&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Plaintiff Dewayne Johnson (center) takes press questions after the initial verdict in his lawsuit against Monsanto, Aug. 10, 2018.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Roundup-Weed-Killer-Cancer/a9b2fda45b8348fcac34ee2dff26dde4/2/0">AP Photo/Paul Elias, File</a></span>
</figcaption>
</figure>
<h1>Probability of causation in cancer cases</h1>
<p>The legal claims against Roundup are torts – cases that one private party brings against another seeking compensation for some kind of harm. Under <a href="http://www.nyulawreview.org/issues/volume-92-number-4/mass-tort-class-actions-past-present-and-future">current tort law</a>, plaintiffs must prove an action by the defendant caused them a specific harm. </p>
<p>For example, if a new automobile is sold with faulty brakes and someone is injured as a result, specific causation is easy to determine, and the car’s manufacturer is liable for compensatory damages. If the manufacturer knew the brakes were faulty, then punitive damages would also be awarded.</p>
<p>But it is much more difficult to determine a specific cause for a cancer diagnosis. Heavy smoking greatly increases risk of lung cancer, but it is impossible to prove that an individual smoker’s lung cancer was due to smoking, since even lifelong nonsmokers sometimes get lung cancer. There is no reliable laboratory test to identify the specific cause of an individual cancer.</p>
<p>In such cases, the question becomes the “risk of harm,” as opposed to “specific causation.”</p>
<p>In the scientific world, the idea of “risk of harm” is analogous to the concept of “probability of causation,” or PC, which the <a href="https://www.cancer.gov/">National Cancer Institute</a> has developed over the last several decades to assess cancer risks associated with <a href="https://radiationcalculators.cancer.gov/">exposure to ionizing radiation</a>. These risk estimates are based in part on the long-term risk of cancer in survivors of the atomic bombings in Hiroshima and Nagasaki.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242378/original/file-20181025-71038-m1aiuo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Many U.S. crops, like this field of sugar beets, are grown from ‘Roundup Ready’ seeds that have been genetically engineered to resist the herbicide. This allows farmers to use Roundup widely to kill weeds.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Biotech-Beets/3798bf98589a4315b1b21e78631f2b99/7/0">AP Photo/Ed Andrieski, File</a></span>
</figcaption>
</figure>
<p>PC values are used in determining worker’s compensation awards. If a worker at a nuclear power plant develops leukemia and his or her cumulative radiation exposure over the years as measured by a badge dosimeter exceeds a certain threshold, then the worker’s leukemia is deemed probably to be the result of radiation exposure, and compensation is warranted.</p>
<p>This approach could be useful in product liability lawsuits when the harm is development of cancer or some other terrible chronic disease for which “specific causation” is unknowable. It would involve two important steps. First, jurors would need to understand the risk analysis itself: What data are used, what assumptions are made, and what statistical modeling was applied?</p>
<p>If the analysis is deemed to be credible, the next thorny issue is determining what threshold should trigger damage awards. If juries believe there was a 10 percent chance that a product gave a plaintiff cancer, should the manufacturer pay? This seems too low, but requiring 99 percent certainty seems unattainable. Perhaps a reasonable threshold would be a 51 percent chance – in other words, more likely than not.</p>
<h1>In praise of litigation</h1>
<p>Tort litigation today does not require juries to meet such precise standards. Nonetheless, despite its inefficiencies and occasional injustices, I believe it is <a href="https://global.oup.com/academic/product/in-praise-of-litigation-9780199380800?cc=us&lang=en&">an important part of American society</a>, and has often led to changes in policy and regulations that have benefited the public. </p>
<p>One well-known example is the case of groundwater contamination and leukemia in the town of <a href="https://serc.carleton.edu/woburn/Case_summary.html">Woburn, Massachusetts, in the mid-1980s</a>. Residents sued two large corporations for groundwater contamination from their operations, which they asserted had caused several cases of leukemia. The lawsuit resulted in a <a href="https://www.penguinrandomhouse.com/books/76093/a-civil-action-by-jonathan-harr/9780679772675/">book</a> and <a href="https://www.imdb.com/title/tt0120633/">movie</a>, both titled “A Civil Action.” It also resulted in an <a href="https://www3.epa.gov/region1/superfund/sites/wellsgh/over.html">Environmental Protection Agency investigation</a> and then <a href="https://www.epa.gov/enforcement/case-summary-epa-receives-over-54-million-wr-grace-bankruptcy">prosecution</a>, including what was at the time the <a href="https://www.joc.com/four-companies-pay-69-million-cleanup_19910709.html">largest settlement paid in the history of the Superfund program in New England</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=433&fit=crop&dpr=1 600w, https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=433&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=433&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=544&fit=crop&dpr=1 754w, https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=544&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/242380/original/file-20181025-71011-4w10ru.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=544&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Plaintiffs in the Woburn trial sought to link contamination of city water wells from dumping like this to a cluster of leukemia cases in their town.</span>
<span class="attribution"><a class="source" href="http://sphweb.bumc.bu.edu/otlt/MPH-Modules/PH/Woburn/Woburn_print.html">Boston University</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>As the Woburn case demonstrated, tort litigation can be a costly and time-consuming process. Many <a href="https://www.legalzoom.com/articles/top-ten-frivolous-lawsuits">lawsuits are frivolous</a>, which compounds the cost. The system <a href="https://www.hg.org/legal-articles/what-is-tort-reform-35441">can certainly be improved</a>, and efforts to do so are ongoing.</p>
<p>But in the end, tort litigation is one of the few avenues available for compensation from large corporations that do the wrong thing and hurt people. And sometimes it can lead to real changes in rules and regulations that will protect the public in general. </p>
<p>It’s too soon to tell whether lawsuits against Monsanto will have limited impact or radically change how Roundup is marketed and used. But the twists and turns in Dewayne Johnson’s case have raised important questions about risk, causation and liability. And this latest ruling suggests that they will not be resolved anytime soon.</p><img src="https://counter.theconversation.com/content/105559/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard G. "Bugs" Stevens does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Thousands of people are suing Monsanto, claiming that its Roundup herbicide gave them cancer. A California judge has reduced the first damage award but let the verdict against Monsanto stand.Richard G. "Bugs" Stevens, Professor, School of Medicine, University of ConnecticutLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1014332018-08-12T22:30:30Z2018-08-12T22:30:30ZJury finds Monsanto liable in the first Roundup cancer trial – here’s what could happen next<figure><img src="https://images.theconversation.com/files/231573/original/file-20180812-2906-l2x3dx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Plaintiff Dewayne Johnson reacts after hearing the verdict in his case against Monsanto at the Superior Court of California in San Francisco, Aug. 10, 2018. </span> <span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Roundup-Weed-Killer-Cancer/a62f4ec26666469380703da844468a60/9/0">Josh Edelson/Pool Photo via AP</a></span></figcaption></figure><p>In the first of many pending lawsuits to go to trial, a jury in San Francisco <a href="https://www.cnn.com/2018/08/10/health/monsanto-johnson-trial-verdict/index.html">concluded on Aug. 10</a> that the plaintiff had developed cancer from exposure to Roundup, Monsanto’s widely used herbicide, and ordered the company to pay US$289 million in damages. </p>
<p>The plaintiff, Dewayne Johnson, had used Roundup in his job as groundskeeper in a California school district. He later developed non-Hodgkin lymphoma. The jury awarded Johnson $39 million in compensatory damages to cover pain, suffering and medical bills due to negligence by Monsanto, plus an additional $250 million in punitive damages. </p>
<p>This means the jury wanted to punish Monsanto because members believed the company deliberately withheld from the public scientific knowledge that glyphosate, the active ingredient in Roundup, was a cancer danger. The size of the damages awarded indicates that the jury was not persuaded by Monsanto’s expert witnesses.</p>
<p>Product liability lawsuits are an important part of American culture. There are many examples of <a href="http://www.latimes.com/opinion/editorials/la-ed-lead-paint-initiative-20180529-story.html">companies knowingly adding toxic agents to their products</a>. So there must be a process for aggrieved individuals who have been harmed to hold these companies accountable.</p>
<p>On the other hand, a lawsuit can be brought against any company for any reason, and some may be frivolous. It is an unfortunate comment on our health care system that so many people are uninsured, and if struck by a dreaded disease, must seek money to deal with it somehow from somewhere.</p>
<p>In many instances it is simply unknown whether a product and its contents are a danger. This verdict is just the first in what could be a long legal battle over Roundup, and <a href="https://theconversation.com/does-monsantos-roundup-cause-cancer-trial-highlights-the-difficulty-of-proving-a-link-100875">proving causality in such cases is not easy</a>. But here are some observations from my own experience <a href="https://scholar.google.com/citations?user=p32Aq9sAAAAJ&hl=en">trying to help figure out why people get cancer</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=372&fit=crop&dpr=1 600w, https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=372&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=372&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=468&fit=crop&dpr=1 754w, https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=468&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/231576/original/file-20180812-2912-1l7g8pl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=468&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Asbestos was widely used in flooring, walls, ceilings and pipes until the 1980s, when it was shown to cause lung cancer. Today workers removing asbestos from older buildings wear protective clothes and respirators.</span>
<span class="attribution"><a class="source" href="https://www.army.mil/article/137053/asbestos_can_only_pose_danger_when_airborne">US Army</a></span>
</figcaption>
</figure>
<h2>How credible is the scientific case against Roundup?</h2>
<p>Much of the plaintiff’s case was based on a widely criticized 2015 statement by the <a href="https://www.iarc.fr/">International Agency for Research on Cancer</a>, part of the World Health Organization, that glyphosate was a “probable human carcinogen” (<a href="https://monographs.iarc.fr/agents-classified-by-the-iarc/">Group 2A on its scale</a>). A classification of “human carcinogen” (Group 1) means that a panel of scientists convened by the IARC believes the agent is a cancer hazard to humans, like smoking and ionizing radiation. The 2A classification is not as strong. It means that there is credible evidence, but it does not reach the standard of “beyond a reasonable doubt.”</p>
<p>The IARC’s process for determining carcinogenicity has come under heavy criticism before. In particular, in the early 2000s some observers worried that industry was actually influencing the agency to <a href="https://doi.org/10.1016/S1470-2045(03)00968-9">downgrade its classification of chemical agents</a>. In the Roundup cases, the accusation against the IARC cuts the other way. According to some accounts, it was biased against industry and <a href="https://www.reuters.com/investigates/special-report/who-iarc-glyphosate/">sought a harsh classification for glyphosate</a>. </p>
<p>The IARC has provided a <a href="http://www.iarc.fr/en/media-centre/iarcnews/pdf/IARC_response_to_criticisms_of_the_Monographs_and_the_glyphosate_evaluation.pdf">detailed defense of its process in the glyphosate evaluation</a>. It has also published a <a href="https://www.iarc.fr/en/media-centre/iarcnews/2016/glyphosate_IARC2016.php">monograph on glyphosate</a> with all the gory details of the science behind its evaluation.</p>
<p>I served on a monograph working group in 2007 for an IARC assessment of <a href="https://monographs.iarc.fr/iarc-monographs-on-the-evaluation-of-carcinogenic-risks-to-humans-23/">whether shift work was a potential cancer hazard</a>. I have also participated in three other meetings sponsored by IARC over the years, so I have seen the agency’s process up close. In my view, IARC personnel go to great lengths to ensure objectivity and scientific rigor. </p>
<p>This does not mean that their classifications are the last word. In fact, the agency has often changed its classification of an agent based on new evidence after initial evaluation. Sometimes it has become more certain that the agent poses a hazard, but in other cases it has downgraded the hazard.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/dx9pQe7d-sI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Monsanto argues that hundreds of tests have shown Roundup does not pose health risks, but several thousand plaintiffs are suing the company, charging that glyphosate gave them cancer.</span></figcaption>
</figure>
<h2>What path for glyphosate?</h2>
<p>Glyphosate and Monsanto could follow the path of the <a href="https://www.asbestos.com/companies/johns-manville/">Johns-Manville company</a>, which started manufacturing asbestos products in the 1880s. After many epidemiological studies showed that exposure to asbestos caused very high rates of lung cancer – primarily pleural mesothelioma – and much litigation, the company <a href="https://www.washingtonpost.com/archive/business/1990/11/20/a-history-of-asbestos-and-the-manville-trust-fund/fb60ed34-2a94-4570-9648-9e2efb8167f0/?utm_term=.8fd35c1cc152">went bankrupt in 1982</a>. Its assets were reorganized to form the <a href="http://mantrust.claimsres.com/">Manville Trust</a>, which allocates monetary damages to people harmed by asbestos.</p>
<p>Some products still contain small quantities of asbestos today, including <a href="https://www.maacenter.org/blog/5-types-of-products-that-still-contain-asbestos/">motor vehicle parts and fireproof clothing</a>. The Environmental Protection Agency tried to ban it in 1989, but was overturned by a federal court. Nonetheless, because asbestos is so clearly linked to cancer, most companies <a href="https://slate.com/business/2018/08/the-trump-administration-is-not-bringing-back-asbestos.html">avoid it now for fear of liability</a>.</p>
<p>Alternatively, glyphosate may follow the route of <a href="http://enhs.umn.edu/current/saccharin/fda.html">saccharin</a>, an artificial sweetener <a href="https://www.sciencehistory.org/distillations/magazine/the-pursuit-of-sweet">discovered in the late 1870s</a>. In 1970 scientists reported that saccharin caused bladder cancer in rats, which led the U.S. Food and Drug Administration to <a href="https://www.nytimes.com/1977/03/11/archives/saccharin-ban-causes-storm-of-complaints-fda-saccharin-ban-causing.html">propose a ban</a> on this extremely popular product in 1977. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=769&fit=crop&dpr=1 600w, https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=769&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=769&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=966&fit=crop&dpr=1 754w, https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=966&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/231578/original/file-20180812-2918-p3b8sx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=966&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A 1946 advertisement suggested that cigarettes were safe by showing a doctor smoking. Scientific evidence later showed that heavy smoker had 10 to 20 times higher risk of developing cancer than non-smokers.</span>
<span class="attribution"><a class="source" href="http://tobacco.stanford.edu/tobacco_main/images.php?token2=fm_st001.php&token1=fm_img0002.php&theme_file=fm_mt001.php&theme_name=">SRITA</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>However, after much more research – including toxicology in rats and epidemiologic studies in people – the IARC downgraded saccharin from a classification of “2B: possible human carcinogen” to “3: not classifiable,” and the U.S. National Toxicology Program <a href="https://ntp.niehs.nih.gov/ntp/roc/content/appendix_b.pdf">removed saccharin from a 2016 report on carcinogens</a>. As it turned out, the mechanism for causing bladder cancer in rats did not apply to people, and epidemiological studies showed no association.</p>
<p>Monsanto will undoubtedly appeal this initial decision, and it could be years before the issue is settled once and for all. But with this verdict, the onus is now on Monsanto to provide compelling evidence that Roundup is safe in other trials that soon will follow.</p><img src="https://counter.theconversation.com/content/101433/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard G. "Bugs" Stevens does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A jury concluded on Aug. 10 that exposure to the herbicide Roundup caused Dewayne Johnson’s cancer and ordered the company to pay $289 million in damages. Thousands more claims are pending.Richard G. "Bugs" Stevens, Professor, School of Medicine, University of ConnecticutLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/997082018-07-25T10:38:01Z2018-07-25T10:38:01ZAI more accurate than animal testing for spotting toxic chemicals<figure><img src="https://images.theconversation.com/files/228869/original/file-20180723-189332-1iznxa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">These rats are in special cages for urine collection. Every year, millions of animals are used for testing chemicals that are used in industrial products.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/animal-experiments-urine-collection-using-white-738846352?src=au4jbW6OZYGllstFIRXYcQ-1-87">By unoL/shutterstock.com</a></span></figcaption></figure><p>Most consumers would be dismayed with how little we know about the majority of chemicals. Only 3 percent of industrial chemicals – mostly drugs and pesticides – are comprehensively tested. Most of the 80,000 to 140,000 chemicals in consumer products have not been tested at all or just examined superficially to see what harm they may do locally, at the site of contact and at extremely high doses.</p>
<p><a href="https://scholar.google.com/citations?user=qwAR168AAAAJ&hl=en">I am a physician and former head of the European Center for the Validation of Alternative Methods of the European Commission</a> (2002-2008), and I am dedicated to finding faster, cheaper and more accurate methods of testing the safety of chemicals. To that end, I now lead a new program at Johns Hopkins University to revamp the safety sciences.</p>
<p>As part of this effort, we have now developed a computer method of testing chemicals that could save more than a US$1 billion annually and more than 2 million animals. Especially in times where the <a href="https://www.houstonchronicle.com/opinion/outlook/article/Rolling-back-chemical-security-regulations-is-13085922.php">government is rolling back regulations</a> on the chemical industry, new methods to identify dangerous substances are critical for human and environmental health. </p>
<h2>How the computer took over from the lab rat</h2>
<p>Our computerized testing is possible because of <a href="http://ec.europa.eu/environment/chemicals/reach/reach_en.htm">Europe’s REACH</a> (Registration, Evaluation, Authorizations and Restriction of Chemicals) legislation: It was the first worldwide regulation to systematical log existing industrial chemicals. Over a period of one decade from 2008 to 2018, at least those chemicals produced or marketed at more than 1 ton per year in Europe had to be registered with increasing safety test information depending on the quantity sold. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/228888/original/file-20180723-189332-1rk6pkk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/228888/original/file-20180723-189332-1rk6pkk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/228888/original/file-20180723-189332-1rk6pkk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/228888/original/file-20180723-189332-1rk6pkk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/228888/original/file-20180723-189332-1rk6pkk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/228888/original/file-20180723-189332-1rk6pkk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/228888/original/file-20180723-189332-1rk6pkk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Thousands of new chemicals are developed and used each year in consumer products without being tested for toxicity.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/chemistry-reaction-formula-toning-135146540">By Garsya/shutterstock.com</a></span>
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</figure>
<p><a href="http://doi.org/10.1038/4601080a">Our team published a critical analysis</a> of European testing demands in 2009 that concluded the demands of the legislation could only be met by adopting new methods of chemical analysis. Europe does not track new chemicals below an annual market or production volume of 1 ton. But the similar size U.S. chemical industry brings about 1,000 chemicals at this tonnage range to the market each year. However, Europe does a much better job in requesting safety data. This also highlights how many new substances should be assessed every year even when they are produced in small quantities below 1 ton, which are not regulated in Europe. Inexpensive and fast computer methods lend themselves to this purpose.</p>
<p>Our group took advantage of the fact that REACH made its safety data on registered chemicals publicly available. In 2016, we reformatted the REACH data, making it machine-readable and creating <a href="http://doi.org/10.1038/nature.2016.19365">the largest toxicological database</a> ever. It logged 10,000 chemicals and connected them to the 800,000 associated studies.</p>
<p>This laid the foundation for testing whether animals tests – considered the gold standard for safety testing – were reproducible. Some chemicals were tested surprisingly often in the same animal test. For example, two chemicals were tested more than 90 times in rabbit eyes; 69 chemicals were tested more than 45 times. This enormous waste of animals, however, enabled us to study whether these animal tests yielded consistent results. </p>
<p>Our analysis showed that these tests, which consume more than 2 million animals per year worldwide, are simply not very reliable – when tested in animals a chemical known to be toxic is only proven so in about 70 percent of repeated animal tests. These were animal tests done according to OECD test guidelines under Good Laboratory Practice – which is to say, the best you can get. This clearly shows that the quality of these tests is overrated and agencies must try alternative strategies to assess the toxicity of various compounds.</p>
<h2>Big data more reliable than animal testing</h2>
<p>Following the vision of <a href="http://doi.org/10.1038/460208a">Toxicology for the 21st Century</a>, <a href="https://ncats.nih.gov/tox21/about">a movement led by U.S. agencies</a> to revamp safety testing, important work was carried out by my Ph.D. student Tom Luechtefeld at the Johns Hopkins <a href="http://caat.jhsph.edu">Center for Alternatives to Animal Testing</a>. Teaming up with Underwriters Laboratories, we have now leveraged an expanded database and machine learning to predict toxic properties. <a href="https://doi.org/10.1093/toxsci/kfy152">As we report</a> in the journal Toxicological Sciences, we developed a novel algorithm and database for analyzing chemicals and determining their toxicity – what we call read-across structure activity relationship, RASAR. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/228877/original/file-20180723-189338-15dfob2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/228877/original/file-20180723-189338-15dfob2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=379&fit=crop&dpr=1 600w, https://images.theconversation.com/files/228877/original/file-20180723-189338-15dfob2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=379&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/228877/original/file-20180723-189338-15dfob2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=379&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/228877/original/file-20180723-189338-15dfob2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=477&fit=crop&dpr=1 754w, https://images.theconversation.com/files/228877/original/file-20180723-189338-15dfob2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=477&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/228877/original/file-20180723-189338-15dfob2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=477&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">This graphic reveals a small part of the chemical universe. Each dot represents a different chemical. Chemicals that are close together have similar structures and often properties.</span>
<span class="attribution"><span class="source">Thomas Hartung</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>To do this, we first created an enormous database with 10 million chemical structures by adding more public databases filled with chemical data, which, if you crunch the numbers, represent 50 trillion pairs of chemicals. A supercomputer then created a map of the chemical universe, in which chemicals are positioned close together if they share many structures in common and far where they don’t. Most of the time, any molecule close to a toxic molecule is also dangerous. Even more likely if many toxic substances are close, harmless substances are far. Any substance can now be analyzed by placing it into this map. </p>
<p>If this sounds simple, it’s not. It requires half a billion mathematical calculations per chemical to see where it fits. The chemical neighborhood focuses on 74 characteristics which are used to predict the properties of a substance. Using the properties of the neighboring chemicals, we can predict whether an untested chemical is hazardous. For example, for predicting whether a chemical will cause eye irritation, our computer program not only uses information from similar chemicals, which were tested on rabbit eyes, but also information for skin irritation. This is because what typically irritates the skin also harms the eye. </p>
<h2>How well does the computer identify toxic chemicals?</h2>
<p>This method will be used for new untested substances. However, if you do this for chemicals for which you actually have data, and compare prediction with reality, you can test how well this prediction works. We did this for 48,000 chemicals that were well characterized for at least one aspect of toxicity, and we found the toxic substances in 89 percent of cases. </p>
<p>This is clearly more accurate that the corresponding animal tests which only yield <a href="http://doi.org/10.1038/4601080a">the correct answer 70 percent of the time</a>. The RASAR shall now be formally validated by an interagency committee of 16 U.S. agencies, including the EPA and FDA, that will challenge our computer program with chemicals for which the outcome is unknown. This is a prerequisite for acceptance and use in many countries and industries.</p>
<p>The potential is enormous: The RASAR approach is in essence based on chemical data that was registered for the 2010 and 2013 REACH deadlines. If our estimates are correct and chemical producers would have not registered chemicals after 2013, and instead used our RASAR program, we would have saved 2.8 million animals and $490 million in testing costs – and received more reliable data. We have to admit that this is a very theoretical calculation, but it shows how valuable this approach could be for other regulatory programs and safety assessments.</p>
<p>In the future, a chemist could check RASAR before even synthesizing their next chemical to check whether the new structure will have problems. Or a product developer can pick alternatives to toxic substances to use in their products. This is a powerful technology, which is only starting to show all its potential.</p><img src="https://counter.theconversation.com/content/99708/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Thomas Hartung consults Underwriters Laboratories (UL) and receives shares of their respective sales. His PhD student Tom Luechtefeld received funding from an NIH training grant. </span></em></p>Testing new industrial chemicals is essential for public health and the environment. But animal testing is costly, and too many chemicals are left untested. A new AI tool may solve the problem.Thomas Hartung, Professor of Environmental Health and Engineering, Johns Hopkins UniversityLicensed as Creative Commons – attribution, no derivatives.