tag:theconversation.com,2011:/us/topics/toxin-1292/articlesToxin – The Conversation2023-08-10T20:00:53Ztag: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>
<hr>
<p>
<em>
<strong>
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>
</strong>
</em>
</p>
<hr>
<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>
<hr>
<p>
<em>
<strong>
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>
</strong>
</em>
</p>
<hr>
<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/2037632023-04-18T03:28:33Z2023-04-18T03:28:33ZWhen did you have your last tetanus vaccine? A booster dose may save your life<figure><img src="https://images.theconversation.com/files/521445/original/file-20230418-18-3hqftn.jpg?ixlib=rb-1.1.0&rect=327%2C35%2C7482%2C5199&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/covid-vaccine-plaster-doctor-patient-consulting-2211549193">Shutterstock</a></span></figcaption></figure><p>NSW Health <a href="https://twitter.com/NSWHealth/status/1646283387496443906">recently reported</a> three cases of tetanus and the tragic death of a woman in her 80s – the first tetanus fatality in the state in 30 years. </p>
<p>Tetanus is a rare but potentially fatal disease. Thankfully, it’s preventable – being up to date with tetanus vaccination is your best protection.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1646359040266731520"}"></div></p>
<h2>What is tetanus and how do you get it?</h2>
<p>The bacteria that causes tetanus is called <em>Clostridium tetani</em>. Spores can enter your body usually following a skin wound, puncture or injury. </p>
<p>Tetanus cannot be transmitted from person to person. </p>
<p>The spores are ubiquitous, found in soil, dust and animal waste. They can <a href="https://www.elsevierhealth.com.au/plotkins-vaccines-9780323357616.html">persist</a> in the environment for months to years, and are remarkably hardy – they’re even resistant to boiling and a number of disinfectants. </p>
<figure class="align-center ">
<img alt="Person gardens in soil with their bare hands" src="https://images.theconversation.com/files/521442/original/file-20230418-28-vlw6xx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/521442/original/file-20230418-28-vlw6xx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/521442/original/file-20230418-28-vlw6xx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/521442/original/file-20230418-28-vlw6xx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/521442/original/file-20230418-28-vlw6xx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/521442/original/file-20230418-28-vlw6xx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/521442/original/file-20230418-28-vlw6xx.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">The bacteria that causes tetanus can remain in soil for years.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/q13Zq1Jufks">Sandie Clarke/Unsplash</a></span>
</figcaption>
</figure>
<p>Once in a wound, the bacteria can grow and produce a toxin. It is the toxin that acts on your nervous system to cause muscle rigidity and painful spasms. </p>
<h2>What are the symptoms?</h2>
<p>One <a href="https://www.uptodate.com/contents/tetanus">classic symptom</a> of tetanus is “lockjaw”, where the muscles around your mouth go into spasms. This makes it difficult to eat and speak but patients maintain full consciousness or awareness. The muscle contractions and spasms are intensely painful and can be triggered by loud noises, physical contact or even light.</p>
<p>Patents with tetanus are commonly treated in an intensive care unit and require cleaning of the wound, antibiotics and injections of anti-toxin, known as human tetanus immunoglobulin, as well as a vaccine. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/at-least-five-reasons-you-should-wear-gardening-gloves-89451">(At least) five reasons you should wear gardening gloves</a>
</strong>
</em>
</p>
<hr>
<p>In severe cases, spasms of muscles surrounding your airways and lungs, alongside high and low blood pressure and heart rhythm abnormalities can lead to death. </p>
<p>Despite the best treatment, about <a href="https://link.springer.com/article/10.17269/s41997-022-00732-7#:%7E:text=From%201995%20to%202019%2C%20a,range%3A%2043%E2%80%9393">2</a>-<a href="https://www.gov.uk/government/publications/tetanus-in-england-annual-reports/tetanus-in-england-2021#:%7E:text=tetanus%20is%20a%20severe%2C%20potentially,per%20year%20over%20previous%20years">10</a>% of patients die. </p>
<h2>How does the vaccine work?</h2>
<p>In Australia, tetanus is rare because of high vaccination coverage, with around <a href="https://www1.health.gov.au/internet/main/publishing.nsf/Content/2A15CD097063EF40CA2587CE008354F1/$File/summary_of_national_surveillance_data_on_vaccine_preventable_diseases_in_australia_2016_2018_final_report.pdf">14 cases</a> reported to health authorities a year.</p>
<p>Tetanus can occur at any age, but is more common in older adults who have never been vaccinated or were vaccinated more than ten years ago. </p>
<p>The vaccine is very effective in preventing tetanus. Tetanus vaccination stimulates the production of antibodies, also known as antitoxin. This means vaccination doesn’t stop <em>Clostridium tetani</em> growing in contaminated wounds. Rather, it protects against the effects of the toxin.</p>
<figure class="align-center ">
<img alt="Nurse vaccinates child" src="https://images.theconversation.com/files/521447/original/file-20230418-18-jwzs1z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/521447/original/file-20230418-18-jwzs1z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/521447/original/file-20230418-18-jwzs1z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/521447/original/file-20230418-18-jwzs1z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/521447/original/file-20230418-18-jwzs1z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/521447/original/file-20230418-18-jwzs1z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/521447/original/file-20230418-18-jwzs1z.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">Vaccination protects you from the effects of the toxin.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-doctor-putting-medical-plaster-girl-1921268393">Shutterstock</a></span>
</figcaption>
</figure>
<h2>When do we need a tetanus shot?</h2>
<p>Tetanus vaccination has been available in Australia since <a href="https://www.health.vic.gov.au/immunisation/vaccine-history-timeline">1925</a>. It’s currently on the National Immunisation Program (NIP) as an initial five-dose schedule for infants and children until five years of age, administered as a combined diphtheria-tetanus-acellular pertussis (DTPa) vaccine. </p>
<p><a href="https://doi.org/10.33321/cdi.2022.46.60">Most children</a> (97%) in Australia complete this primary immunisation schedule. </p>
<p>The <a href="https://www.who.int/publications/i/item/WHO-WER9206">level of antitoxin needed</a> for protection from tetanus is 0.1-0.2 international units (IU) per millilitre (mL). This level is <a href="https://pubmed.ncbi.nlm.nih.gov/16822597/">reached</a> following a fifth dose, at age four to six years. </p>
<p>But by middle age, <a href="https://pubmed.ncbi.nlm.nih.gov/30318003/">about 20%</a> of Australians have low or undetectable levels of antitoxin. This places them at risk of contracting tetanus after a wound or injury. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-are-you-up-to-date-with-your-vaccinations-116510">Health Check: are you up to date with your vaccinations?</a>
</strong>
</em>
</p>
<hr>
<p>A single dose of tetanus vaccine produces protective levels of antitoxin in these people. This is why a booster dose of tetanus vaccine is <a href="https://immunisationhandbook.health.gov.au/contents/vaccine-preventable-diseases/tetanus">recommended</a> for the following people if their last dose was more than ten years ago: </p>
<ul>
<li><p>adults at 50 years of age</p></li>
<li><p>adults aged 65 years or over</p></li>
<li><p>travellers, of any age, to countries where it may be difficult to access timely health services if you sustain a tetanus-prone wound (any wound other than a clean, minor cut).</p></li>
</ul>
<p>If you have a tetanus-prone wound and there is any doubt about your tetanus immunisation status, you should receive tetanus immunoglobulin as soon as possible. You should also receive a tetanus vaccine. </p>
<p>If you’re overseas, it could be hard and expensive to get access to both tetanus immunoglobulin and tetanus vaccine.</p>
<h2>How do I check my vaccination status?</h2>
<p>If you’re over 14 years of age, you can check your vaccine history:</p>
<ul>
<li><p>online, by setting up a myGov account and accessing your Medicare online account through the Express Plus Medicare mobile app</p></li>
<li><p>by calling the <a href="https://www.servicesaustralia.gov.au/australian-immunisation-register">Australian Immunisation Register</a> on 1800 653 809</p></li>
<li><p>by asking your doctor or immunisation provider to <a href="https://www.health.gov.au/topics/immunisation/getting-vaccinated/check-immunisation-history">print a copy</a> of your immunisation records. </p></li>
</ul>
<p>If it has been more than ten years since your last dose, ask your GP about getting a booster. It could save your life.</p><img src="https://counter.theconversation.com/content/203763/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nicholas Wood has previously received funding from the NHMRC for a Career Development Fellowship.</span></em></p><p class="fine-print"><em><span>Helen Quinn 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>Tetanus is a rare but potentially fatal disease. Being up to date with tetanus vaccination is your best protection.Nicholas Wood, Associate Professor, Discipline of Childhood and Adolescent Health, University of SydneyHelen Quinn, Senior Research Fellow, National Centre for Immunisation Research and Surveillance & Senior Lecturer, Children’s Hospital Westmead Clinical School, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1960512023-01-12T04:14:50Z2023-01-12T04:14:50Z‘More potent than cyanide’: how to stay safe from blue-ringed octopus this summer<figure><img src="https://images.theconversation.com/files/504135/original/file-20230112-13-yk30h3.jpg?ixlib=rb-1.1.0&rect=26%2C22%2C2968%2C1661&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Kris Mikael Krister/Unsplash</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>As an octopus biologist, I get a call from the media every summer because someone has had an encounter with a blue-ringed octopus. Thankfully, everyone has been OK. </p>
<p>Blue-ringed octopus are famed for being one of the most venomous animals on the planet, and the symptoms from a bite are the stuff of nightmares. But how worried do you need to be?</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/who-would-win-in-a-fight-between-an-octopus-and-a-seabird-two-marine-biologists-place-their-bets-158520">Who would win in a fight between an octopus and a seabird? Two marine biologists place their bets</a>
</strong>
</em>
</p>
<hr>
<h2>1,000 times more powerful than cyanide</h2>
<p>It’s a common myth that blue-ringed octopus are found only in the tropics. These tiny marine animals are, in fact, found all around Australia, including Tasmania.</p>
<p>There are <a href="https://www.publish.csiro.au/book/6526/">three official species</a> in Australia, with a maximum size ranging from 12 to 22 centimetres, and they are all extremely venomous. There are <a href="https://museumsvictoria.com.au/article/blue-ringed-octopus/">also many</a> scientifically “undescribed” species, which have yet to be named and officially added to the blue-ringed family.</p>
<p>The venom of blue-ringed octopus contains tetrodotoxin, a potent neurotoxin <a href="https://www.mdpi.com/2072-6651/6/2/693">claimed to be</a> a thousand times more potent to humans than cyanide. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/504137/original/file-20230112-24-xqf111.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Blue-ringed octopus are found all over Australia.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>First discovered in pufferfish, tetrodotoxin <a href="https://www.cell.com/current-biology/pdf/S0960-9822(16)30596-6.pdf">is actually found in</a> more than 100 species including the Panamanian golden frog and rough-skinned newt. But levels of the toxin varies hugely between species, and levels in blue-ringed octopus are high. </p>
<p>Surprisingly, scientists are debating where blue-ringed octopus and other marine animals source their tetrodotoxin. <a href="https://www.sciencedirect.com/science/article/pii/S0166445X1830465X">One theory</a> is that it’s produced by bacteria that live inside the host species, the other is that it’s sourced from the diet. </p>
<p>Most of these animals use tetrodotoxin for defence, but blue-ringed octopus also use it to hunt and kill their prey, such as fish and crabs. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pufferfish" src="https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/504138/original/file-20230112-4958-hwkux8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tetrodotoxin is found in over 100 species, including pufferfish.</span>
<span class="attribution"><span class="source">Stelio Puccinelli/Unsplash</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Are blue-ringed octopus proliferating?</h2>
<p>The <a href="https://www.dailymail.co.uk/news/article-5397513/Record-number-blue-ringed-octopus-sightings-Adelaide.html">media often report</a> spikes or record numbers in blue-ringed octopus sightings. </p>
<p>While we don’t have the long-term data to confirm this, the populations of some octopus species <a href="https://www.sciencedirect.com/science/article/pii/S0960982216303190">are increasing</a>. For example, there <a href="https://reporterre.net/Il-n-y-a-plus-que-ca-En-Bretagne-l-inquietante-invasion-des-poulpes">are reports</a> the common European octopus is proliferating in France right now. </p>
<p>Octopus are short-lived – the blue-ringed octopus only lives for <a href="https://link.springer.com/article/10.1007/BF00348686">a few months</a> – and are highly responsive to changing environmental conditions. </p>
<p>Hypothetically, some human-made habitats, such as breakwalls and lobster pots, or marine litter, such as bottles and cans, could be providing additional habitat for blue-ringed octopus. Likewise, climate change could confer an advantage to some octopus species that can better adapt to <a href="https://www.publish.csiro.au/mf/pdf/MF14126">warming waters</a>.</p>
<p>But we simply do not know if this is the case for blue-ringed octopus. Octopus populations may also undergo natural “boom and bust” cycles in response to fluctuations in temperature, food, and other factors in their environment, resulting in rapid increases and decreases in population numbers. </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/tv/CZVjyUYqnTy/?utm_source=ig_web_copy_link","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>How to keep safe</h2>
<p>Blue-ringed octopus deliver venom by biting using their parrot-like beak, which is found at the base of the arms. </p>
<p>Blue-ringed octopus bites are rare – they are docile, shy animals and are not interested in people. But they may bite when they are threatened or provoked, so <em>NEVER, EVER</em> pick them up. </p>
<p>And remember, these octopus <a href="https://journals.biologists.com/jeb/article/215/21/3752/19182/How-does-the-blue-ringed-octopus-Hapalochlaena">only flash</a> their characteristic blue rings when upset, so stay clear of any small octopus, no matter what they look like. </p>
<p>Blue-ringed octopus are found in shallow coastal waters, including the foreshore, so accidental encounters do happen. Their <a href="https://www.publish.csiro.au/book/6526/">preferred habitats</a> include rocky reefs and coral reefs, seagrass and algal beds, and rubble. Given they’re found throughout the Indo-West Pacific, you may encounter them while on holiday.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Blue-ringed octopus in a shallow tide pool" src="https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/504139/original/file-20230112-34767-8nyu7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&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 blue-ringed octopus in a shallow tide pool.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Be careful exploring rock pools, cracks or crevices, or picking up empty shells or bottles at the beach, where the octopus may make a home or den, or even when retrieving fishing gear, such as octopus pots or lobster pots.</p>
<p>Curious, young children may also be at risk of an encounter as they explore the beach environment – I know my own toddler would seek out the ideal octopus habitat if given a chance. </p>
<p>This month also, many dead blue-ringed octopus were found on the beach after a mass death event of marine critters in <a href="https://www.abc.net.au/news/2023-01-06/carnage-of-dead-marine-life-on-beaches-near-murray-mouth/101831330">South Australia</a>. It’s best not to pick them up as they could be dying and stressed. Please also keep pets and young children well away as ingestion could lead to poisoning. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-could-octopuses-evolve-until-they-take-over-the-world-and-travel-to-space-156493">Curious Kids: could octopuses evolve until they take over the world and travel to space?</a>
</strong>
</em>
</p>
<hr>
<h2>What to do if bitten, and symptoms to watch for</h2>
<p>All three blue-ringed octopus species in Australia <a href="https://www.publish.csiro.au/book/6526/">have killed people</a>, but cases are extremely rare. The severity of symptoms <a href="http://www.toxinology.com/generic_static_files/A%20Clinician's%20Guide%20to%20Venomous%20Bites%20&%20Stings%202013.pdf">depends on</a> how much venom someone receives.</p>
<p>A mild case of envenomation may result in tingling around the mouth and mild weakness. A <a href="http://www.toxinology.com/generic_static_files/A%20Clinician's%20Guide%20to%20Venomous%20Bites%20&%20Stings%202013.pdf">severe case</a> may lead to flaccid paralysis (weak or limp muscles), including respiratory paralysis and the inability to breathe. </p>
<p>A tricky thing with blue-ringed octopus is that bites may be painless, so people can be unaware they have been bitten. But the onset of symptoms can be rapid (within minutes) and so an equally rapid first-aid response is crucial.</p>
<p>If you believe someone has been bitten by a blue-ringed octopus, remove them from water immediately and seek urgent medical care. You do not need to put anything on the bite, such as vinegar or hot water. Rather, pressure bandaging and immobilisation is <a href="http://www.toxinology.com/generic_static_files/A%20Clinician's%20Guide%20to%20Venomous%20Bites%20&%20Stings%202013.pdf">recommended, as for snake bites</a>.</p>
<p>If the envenomation is severe, first aid is also focused on providing basic life support, particularly breathing support. <strong>Full first aid response details <a href="http://www.toxinology.com/fusebox.cfm?fuseaction=main.first_aid.firstaid&id=FAD-14">can be found here</a> and <a href="http://www.toxinology.com/generic_static_files/A%20Clinician's%20Guide%20to%20Venomous%20Bites%20&%20Stings%202013.pdf">here</a>.</strong></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-hidden-world-of-octopus-cities-and-culture-shows-why-its-wrong-to-farm-them-180536">The hidden world of octopus cities and culture shows why it’s wrong to farm them</a>
</strong>
</em>
</p>
<hr>
<p>Importantly, undertaking a first-aid course may help equip you with some of the skills to support a person who has been bitten before medical help arrives. </p>
<p>While there is no antivenom available for a blue-ringed octopus bite, the venom has <a href="http://www.toxinology.com/generic_static_files/A%20Clinician's%20Guide%20to%20Venomous%20Bites%20&%20Stings%202013.pdf">short-lived effects</a> (usually hours). </p>
<p>At the end of the day, enjoy the ocean. But if you see any small octopus, whatever you do, do not pick it up. </p>
<p><em>The author gratefully acknowledges clinical toxinologist, Professor Julian White AM (Women’s & Children’s Hospital, Adelaide), who provided advice on this article.</em></p><img src="https://counter.theconversation.com/content/196051/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zoe Doubleday receives funding from the Australian Research Council, Australian Academy of Science, and Fisheries Research and Development Corporation. </span></em></p>Ranging from 12 to 22 centimetres, these tiny octopus are extremely venomous and found all over Australia. Here’s what to do if you see someone get bitten.Zoe Doubleday, Marine Ecologist and ARC Future Fellow, University of South AustraliaLicensed 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>
<hr>
<p>
<em>
<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>
</strong>
</em>
</p>
<hr>
<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/1601512021-06-07T12:34:52Z2021-06-07T12:34:52ZWhy are some mushrooms poisonous?<figure><img src="https://images.theconversation.com/files/402428/original/file-20210524-17-1a7bsu.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3870%2C2570&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Poisonous or edible?</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/collection-of-poisonous-and-edible-mushrooms-from-royalty-free-image/1019817860">Ekaterina Morozova/iStock via Getty Images Plus</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>Why are some mushrooms poisonous and some are not? – Alice T., age 11</strong></p>
</blockquote>
<hr>
<p>You may have noticed that mushrooms pop up in your yard or in parks right after a rain but don’t last for long. </p>
<p>A mushroom is the above-ground part of a fungus. Most of the time, fungi live as threadlike structures called hyphae underground or in materials like wood. For fungi to reproduce, a mushroom must form above ground.</p>
<p>Some mushrooms are poisonous for the same reason some plants are poisonous – to protect themselves from being eaten so they can reproduce. Other mushrooms use the opposite strategy. They need animals to eat them in order to spread spores through poop. Still other mushrooms have completely different game plans.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Finger shaped fungi release spores that look like smoke." src="https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=412&fit=crop&dpr=1 600w, https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=412&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=412&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=518&fit=crop&dpr=1 754w, https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=518&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/402432/original/file-20210524-17-1r89xz1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=518&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 candlestick fungus, <em>Xylaria hypoxylon</em>, releases its spores.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/xylaria-hypoxylon-candlestick-fungus-royalty-free-image/1286089348">Jasius/Moment via Getty Images</a></span>
</figcaption>
</figure>
<h2>Spreading spores</h2>
<p>Mushrooms develop when the temperature is right and there is enough water. They usually consist of a cap and a stalk. On the underside of the cap, mushrooms produce spores that, like the seeds of plants, produce new fungi. </p>
<p>If you peek under a variety of mushroom caps, you will notice they are not all the same. </p>
<p>Some mushrooms have gills that look like a pleated sheet of paper. Some have pores that look like sponges. And some have toothlike structures. All of these surfaces produce spores. To create a new generation of fungi, spores need to get to new areas – and there are many fascinating ways mushrooms accomplish this. </p>
<p>For some mushrooms, spores simply fall from their caps and are carried to new homes by air currents.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A cluster of mushrooms glow in the dark." src="https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/402426/original/file-20210524-23-b4szbm.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 ghost fungus, <em>Omphalotus nidiformis</em>, at night in an Australian driveway.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/omphalotus-nidiformis-or-ghost-fungus-royalty-free-image/1188626849">Louise Docker Sydney Australia/Moment via Getty Images</a></span>
</figcaption>
</figure>
<p>Other mushrooms attract insects by <a href="https://www.treehugger.com/bioluminescent-fungi-mushrooms-that-glow-in-the-dark-4868794">glowing at night</a>. The glow from fungi in the woods at night can be very strong and is sometimes called foxfire. Insects, which are attracted to the light, inadvertently pick up spores as they investigate the glow and carry them elsewhere when they move on. </p>
<p>Some mushrooms never form an above-ground structure. Instead the mushroom stays underground and is eaten by squirrels and mice, which spread the spores by taking pieces back to their nests and by pooping. Such mushrooms are called truffles, and sometimes people will pay a lot of money for them. </p>
<h2>A window of opportunity</h2>
<p>Since mushrooms don’t last long, it’s important they spread their spores quickly. This is where poisons and toxins can come in. </p>
<p>Mushrooms are pretty tasty to snails, some insects, beetles, chipmunks, squirrels, deer and people. If an animal eats a mushroom, usually its spores are lost – unless they’re the type encased in a protective covering meant to be carried to a new neighborhood in poop.</p>
<p>Scientists have figured out that <a href="https://doi.org/10.1016/0031-9422(95)00773-3">insects and snails avoid eating mushrooms that contain poison</a>. Some mushroom poisons may make the <a href="https://doi.org/10.1007/BF00988513">eater only sick enough to avoid that species in the future</a>, but some can be fatal. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A white gilled mushroom lies on its side in the grass." src="https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=887&fit=crop&dpr=1 600w, https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=887&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=887&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1115&fit=crop&dpr=1 754w, https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1115&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/402424/original/file-20210524-17-1wprn4k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1115&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 deadly poisonous mushroom, <em>Amanita virosa</em>.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/gails_pictures/8552148482">gailhampshire/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>There are many different mushroom poisons. One kind belongs to a group of very beautiful mushrooms, the amanitas, also called “destroying angels” because they are both pretty and deadly. Amanitas are often mistaken for mushrooms that can be eaten, and they <a href="https://en.wikipedia.org/wiki/Amanita_phalloides">cause several deaths worldwide each year</a>. </p>
<p>People use some mushroom poisons in medicine. The poison of the ergot fungus, for example, was developed into a drug <a href="https://doi.org/10.1007/s11916-003-0011-7">used to prevent migraine headaches</a>. </p>
<p>Approximately <a href="http://www.mushroomthejournal.com/greatlakesdata/TopTen/Quest19.html">1%-2% of mushrooms are poisonous to humans</a>. The common term for such a mushroom is a “toadstool,” but there is no easy way to distinguish a poisonous mushroom from one that is edible. So it’s not a good idea to eat mushrooms you find, because it’s hard to be sure whether they’re poisonous or not. </p>
<p>Many mushrooms are healthy and delicious. Just make sure you get them from a store or from someone who is a mushroom expert. </p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/160151/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Karen Hughes receives funding from the U.S. National Science Foundation and the Great Smoky Mountains National Park. </span></em></p>Poison can be a deadly defense that helps a mushroom make sure its spores are spread to new places to grow into baby mushrooms.Karen Hughes, Professor of Mycology, University of TennesseeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1373072020-04-29T12:08:29Z2020-04-29T12:08:29ZNairobi flies: unpacking the mystery of a small beetle with huge burn power<figure><img src="https://images.theconversation.com/files/330726/original/file-20200427-145513-1bov23d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Paederus.</span> <span class="attribution"><span class="source">Ian Jacobs/Flickr</span></span></figcaption></figure><p>A <a href="https://citizentv.co.ke/news/video-panic-over-bizarre-swarm-of-narrow-bee-flies-nairobi-flies-in-kabarnet-town-330665/">huge swarm</a> of small black and red insects were recently seen in a town called Kabarnet, in western Kenya.</p>
<p>Debate has been <a href="https://twitter.com/hashtag/nairobifly">been raging</a> in the local media about what to call the insects: Nairobi fly, Kenya fly, narrow bee fly? There is no official name but “Nairobi fly” <a href="https://www.capitalfm.co.ke/lifestyle/2017/04/24/things-know-nairobi-fly/">seems to be</a> the most commonly used. Other parts of the world have their own local names.</p>
<p>In fact, the insects are neither flies, nor bees. They’re beetles. They belong to the genus <em>Paederus</em> which contains about 600 described species and is part of the beetle family <em>Staphylinidae</em>, commonly known as rove beetles. </p>
<p>They are well known, and feared, for the burns – or dermatitis – that they can cause on human skin. </p>
<p>The genus <em>Paederus</em> was described by the Danish entomologist Johann Christian Fabricius in 1775, though it was known to Chinese medicine over 1,200 years before this. An insect called <em>ch’ing yao ch’ung</em> <a href="https://academic.oup.com/jme/article-abstract/24/2/155/917757">was described</a> in 739 A.D: “It contains a strong poison and when it touches the skin it causes the skin to swell up…”. </p>
<p>But not all species of <em>Paederus</em> contain the toxin. Only about 20 species of the beetle are known to cause the burns.</p>
<p>The two species of rove beetles known as “Nairobi fly”, and many other species of <em>Paederus</em>, are obvious due to their red and black colouration; warning colours of their toxicity. They also have a very long body, typical of rove beetles. </p>
<p>They do not bite or sting. Burns are caused when the beetle is slightly or completely squashed. This releases the ‘juices’ from the haemolymph, the invertebrate equivalent of blood. </p>
<p>The toxin causing these burns is a called pederin. It is <a href="https://www.sciencedirect.com/science/article/pii/S0965174801001151?via%3Dihub">produced by</a> a symbiotic bacteria that lives inside the beetles. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/1wxiKSDM2jE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>Severity of the dermatitis <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-4362.1990.tb04844.x">depends on</a> each individual case, the dose of pederin and duration of contact. Mild cases of dermatitis consist of a slight redness of the skin. Moderate cases will start itching after about 24 hours and develop blisters at about 48 hours – these usually dry out and don’t leave scars. More severe cases could happen if the toxin is more widespread over the body and could cause fever, nerve pains, joint pains or vomiting. When pederin comes into contact with people’s eyes, because of hand rubbing, it <a href="https://academic.oup.com/jme/article-abstract/24/2/155/917757">can cause</a> conjunctivitis – also known as Nairobi eye – and potentially temporary blindness.</p>
<p>Despite the name of the beetle, it is not restricted to Kenya. Cases of dermatitis caused by <em>Paederus</em> are <a href="https://www.ajol.info/index.php/samj/article/view/69775">known to occur</a> in <a href="https://europepmc.org/article/med/17459295">several African countries</a> such as Sierra Leone and Tanzania and other tropical and temperate countries through the world.</p>
<p>In some years the beetles do particularly well and emerge in huge numbers, usually following the rainy season. This is probably due to the high levels of moisture which prevent the beetles from drying up and dying. It is difficult to predict how long swarms persist.</p>
<h2>Why so toxic?</h2>
<p>There are over 64,000 types of rove beetles, most of which hunt other small insects in leaf litter and other terrestrial habitats all over the world. These beetles are important components of our ecosystem since they actively hunt other small insects that could, for example, be harmful pests of crops.</p>
<p>The beetles <a href="https://www.ncbi.nlm.nih.gov/pubmed/26336279">often occur</a> in and <a href="https://academic.oup.com/jme/article-abstract/24/2/155/917757">around</a> agricultural fields and are attracted to light. This is probably the main reason they accumulate in such large numbers around residential areas, where house lights and street lights beam throughout the night.</p>
<p>Rather remarkably, whether a beetle contains pederin or not <a href="https://www.ncbi.nlm.nih.gov/pubmed/28307257">makes very little difference</a> to their predators. The exact reason why some <em>Paederus</em> contain pederin is not known. The most obvious explanation would be to repel predators, but then <a href="https://www.ncbi.nlm.nih.gov/pubmed/28307257">we would expect</a> the beetles to produce the pederin without being partly or fully squashed. An additional problem with this idea is that the acid present in the stomachs of predators that are likely to feed on <em>Paederus</em> has been shown to destroy pederin.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/330724/original/file-20200427-145508-1o00dt4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/330724/original/file-20200427-145508-1o00dt4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/330724/original/file-20200427-145508-1o00dt4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/330724/original/file-20200427-145508-1o00dt4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/330724/original/file-20200427-145508-1o00dt4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/330724/original/file-20200427-145508-1o00dt4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/330724/original/file-20200427-145508-1o00dt4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Paederus dermatitis at neck.</span>
<span class="attribution"><span class="source">TisforThan/Shutterstock</span></span>
</figcaption>
</figure>
<h2>What to do?</h2>
<p>The main preventative measures to reduce contact with <em>Paederus</em> rove beetles include the use of bed nets, long-sleeve clothing and avoiding sitting under lights at night. </p>
<p>If a beetle does land on your skin it should be blown or gently brushed off and not crushed. If your skin does come into contact with juices from the beetles, wash the affected area with soap and water.</p>
<p>One of the problems is when the beetles are in someone’s bed and get crushed by the person moving in their sleep. Placing sticky traps around light sources <a href="https://academic.oup.com/jme/article-abstract/52/4/517/2459629?redirectedFrom=fulltext">may help</a> to manage the numbers of <em>Paederus</em>. </p>
<p>There’s also evidence that the beetle’s toxin might eventually help us. Preliminary research on mice <a href="https://link.springer.com/article/10.1007/BF01897720">suggests that</a> the pederin inside the beetles has the potential to slow the growth of cancerous tumours. </p>
<p>This highlights the need for further research on these incredible little beetles, specifically the symbiotic bacteria and the pederin the bacteria produces and its potential in anti-cancer treatments.</p>
<p>Even the evolutionary relationships between <em>Paederus</em> rove beetles is not well known and would be an important first step in understanding where and how to look for pederin among the hundreds of described and undescribed species.</p><img src="https://counter.theconversation.com/content/137307/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Josh Jenkins Shaw 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>“Nairobi fly” are obvious due to their red and black colouration; these are warning colours of their toxicity.Josh Jenkins Shaw, Systematic Entomologist, Chinese Academy of SciencesLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1246302019-12-20T16:56:16Z2019-12-20T16:56:16ZHangovers happen as your body tries to protect itself from alcohol’s toxic effects<figure><img src="https://images.theconversation.com/files/308125/original/file-20191220-11904-o6bx4v.jpg?ixlib=rb-1.1.0&rect=365%2C121%2C4409%2C3063&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A night of revelry can mean an uncomfortable day after.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/migraine-headache-227278786">Everett Collection/Shutterstock.com</a></span></figcaption></figure><p>Debaucherous evening last night? You’re probably dealing with veisalgia right now.</p>
<p>More commonly known as a hangover, this unpleasant phenomenon <a href="https://time.com/3958046/history-of-hangovers/">has been dogging humanity</a> since our ancestors first happened upon fermentation.</p>
<p>Those nasty vertigo-inducing, cold sweat-promoting and vomit-producing sensations after a raucous night out are all part of your body’s attempt to protect itself from injury after you overindulge in alcoholic beverages. Your liver is working to break down the alcohol you consumed so your kidneys can clear it out ASAP. But in the process, your body’s inflammatory and metabolic reactions are going to lay you low with a hangover.</p>
<p>As long as people have suffered from hangovers, they’ve searched in vain for a cure. Revelers have access to a variety of compounds, products and devices that purport to ease the pain. But there’s a lot of purporting and not a lot of proof. Most have not been backed up well by science in terms of usefulness for hangover treatment, and often their effects don’t seem like they’d match up with what scientists know about the biology of the hangover.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/308010/original/file-20191219-11900-1nrkesq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Drain enough cups of booze in one session and you know what’s bound to follow.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/EEIIm23ktS4">Laura buron/Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Working overtime to clear out the booze</h2>
<p>Hangovers are virtually guaranteed when you drink too much. That amount varies from person to person based on <a href="https://doi.org/10.1111/add.12699">genetic factors</a> as well as whether there are <a href="https://doi.org/10.1111/j.1530-0277.2009.01116.x">other compounds</a> that formed along with ethanol in the fermentation process.</p>
<p>Over the course of a night of heavy drinking, your blood alcohol level continues to rise. Your body labors to break down the alcohol – consumed as ethanol in beer, wine or spirits – forming damaging oxygen free radicals and acetaldehyde, itself a harmful compound. The longer ethanol and acetaldehyde stick around, the more damage they can do to your cellular membranes, proteins and DNA, so your body’s enzymes work quickly to metabolize acetaldehyde to a less toxic compound, acetate.</p>
<p>Over time, your ethanol levels drop through this natural metabolic process. Depending on how much you consumed, you’re likely to experience a hangover as the level of ethanol in your blood slowly returns to zero. Your body is withdrawing from high levels of circulating alcohol, while at the same time trying to protect itself from the effects of alcohol.</p>
<p>Scientists have limited knowledge of the leading causes of the hangover. But they do know that the body’s responses include changes in hormone levels to <a href="https://www.pulsus.com/abstract/alcohol-hangover-its-effects-on-human-body-review-4404.html">reduce dehydration</a> and cellular stress. Alcohol consumption also affects a variety of <a href="https://doi.org/10.1093/alcalc/agz016">neurotransmitter systems</a> in the brain, including glutamate, dopamine and serotonin. Inflammation increases in the body’s tissues, and the healthy gut bacteria in your digestive system take a hit too, promoting <a href="https://doi.org/10.1093/alcalc/agy061">leaky gut</a>.</p>
<p>Altogether, <a href="https://doi.org/10.1093/alcalc/agz016">the combination of all these reactions</a> and protective mechanisms activated by your system gives rise to the experience of a hangover, which can last up to 48 hours.</p>
<h2>Your misery likely has company</h2>
<p>Drinking and socializing are cultural acts, and most hangovers <a href="https://doi.org/10.1080/13676261.2012.693594">do not happen in isolation</a>. Human beings are social creatures, and there’s a high likelihood that at least one other individual feels the same as you the morning after the night before.</p>
<p>Each society has different rules regarding alcohol use, which can affect how people <a href="https://doi.org/10.1016/j.puhe.2011.09.014">view alcohol consumption within those cultures</a>. Drinking is often valued for its relaxing effect and for promoting sociability. So it’s common to see alcohol provided at celebratory events, social gatherings and holiday parties.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=638&fit=crop&dpr=1 600w, https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=638&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=638&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=802&fit=crop&dpr=1 754w, https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=802&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/308014/original/file-20191219-11939-1p3ym3k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=802&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">For many people, ‘partying’ is synonymous with ‘drinking.’</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/BnzqQwerUOY">Lidya Nada/Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>In the United States, drinking alcohol is largely embraced by mainstream culture, which may even promote behaviors involving <a href="https://doi.org/10.1186/1471-2458-9-51">excessive drinking</a>. It should be no surprise that overindulgence goes hand in hand with these celebratory social events – and leads to hangover regrets a few hours later. </p>
<p>Your body’s reactions to high alcohol intake and the sobering-up period can influence mood, too. The combination of fatigue that you experience from sleep deprivation and hormonal stress reactions, in turn, affect your neurobiological responses and behavior. As your body is attempting to repair itself, you’re more likely to be easily irritated, exhausted and want nothing more than to be left alone. Of course, your <a href="https://doi.org/10.2174/1874473711003020080">work productivity takes a dramatic hit</a> the day after an evening of heavy drinking.</p>
<p>When all is said and done, you’re the cause of your own hangover pain, and you’re the one who must pay for all the fun of the night before. But in short order, you’ll <a href="https://doi.org/10.1016/j.addbeh.2008.06.014">forget how excruciating your last hangover</a> was. And you may very soon talk yourself into doing the things you swore you’d never do again.</p>
<h2>Speeding up recovery</h2>
<p>While pharmacologists <a href="https://scholar.google.com/citations?user=miPd9ysAAAAJ&hl=en&oi=ao">like</a> <a href="https://scholar.google.com/citations?user=ZLL4yjwAAAAJ&hl=en&oi=ao">us</a> understand a bit about how hangovers work, we still lack a true remedy.</p>
<p>Countless articles describe a <a href="http://www.cjhp.org/volume16Issue1_2018/documents/79-90_CJHP2018Issue1_Kruger.pdf">variety of foods</a>, caffeine, ion replenishment, <a href="https://doi.org/10.1016/j.neulet.2018.01.030">energy drinks</a>, <a href="https://www.ncbi.nlm.nih.gov/pubmed/30462386">herbal supplements</a> including <a href="https://doi.org/10.3390/molecules21010064">thyme and ginger, vitamins</a> and the “hair of the dog” as ways to <a href="https://doi.org/10.1002/hup.2600">prevent and treat hangovers</a>. But the evidence isn’t really there that any of these work effectively. They’re just not scientifically validated or well reproduced.</p>
<p>For example, Kudzu root (<em>Pueraria lobata</em>), a popular choice for hangover remedies, has primarily been investigated for its effects in reducing alcohol-mediated stress and hangover. But at the same time, Kudzu root appears to <a href="https://doi.org/10.1016/j.alcohol.2007.07.009">inhibit the enzymes that break down acetaldehyde</a> – not good news since you want to clear that acetaldehyde from your system quickly.</p>
<p>To fill this knowledge gap, our lab is <a href="https://pharmacyschool.usc.edu/directory/?expert=jing.liangphd">working with colleagues</a> to see if we can find scientific evidence for or against potential hangover remedies. We’ve focused on the benefits of dihydromyricetin, a Chinese herbal medicine that is currently available and formulated as a dietary supplement for hangover reduction or prevention.</p>
<p>Dihydromyricetin appears to work its magic by <a href="https://www.ncbi.nlm.nih.gov/pubmed/17048612">enhancing alcohol metabolism</a> and reducing its toxic byproduct, acetaldehyde. From our findings in mice models, we are collecting data that support the usefulness of dihydromyricetin in <a href="http://www.koreascience.or.kr/article/JAKO200003042335835.page">increasing the expression and activity of enzymes</a> responsible for ethanol and acetaldehyde metabolism in the liver, where ethanol is primarily broken down. These findings explain one of the several ways dihydromyricetin protects the body against alcohol stress and hangover symptoms. </p>
<p>We are also studying how this enhancement of alcohol metabolism results in changes in alcohol drinking behaviors. Previously, dihydromyricetin was found to counteract the relaxation affect of drinking alcohol by interfering with particular neuroreceptors in the brain; <a href="https://doi.org/10.1523/JNEUROSCI.4639-11.2012">rodents didn’t become as intoxicated</a> and consequently reduced their ethanol intake. Through this combination of mechanisms, we hope to illustrate how DHM might reduce the downsides of excessive drinking beyond the temporary hangover, and potentially reduce drinking behavior and damage associated with heavy alcohol consumption.</p>
<p>Of course, limiting alcohol intake and substituting water for many of those drinks during an evening out is probably the best method to avoid a painful hangover. However, for those times when one alcoholic beverage leads to more than a few more, be sure to stay hydrated and catch up on rest. Your best bet for a smoother recovery is probably some combination of <a href="https://doi.org/10.1016/j.alcohol.2019.10.006">nonsteroidal anti-inflammatory drug</a> like ibuprofen, Netflix and a little downtime. </p>
<p>[ <em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/124630/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dr. Davies received a Donation from 82 Labs two years ago to conduct basic research on DHM that is mentioned in the article. </span></em></p><p class="fine-print"><em><span>Joshua Silva and Terry David Church do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Researchers know the basic biology of what happens to your system after a night of heavy drinking. Unfortunately, evidence-based cures for the common hangover are still at the investigation stage.Daryl Davies, Professor of Clinical Pharmacy, University of Southern CaliforniaJoshua Silva, Ph.D. Candidate in Clinical and Experimental Therapeutics, University of Southern CaliforniaTerry David Church, Assistant Professor of Regulatory and Quality Sciences, University of Southern CaliforniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1165062019-06-27T17:54:59Z2019-06-27T17:54:59ZWhy lead is dangerous, and the damage it does<figure><img src="https://images.theconversation.com/files/281212/original/file-20190625-81770-1xsoxow.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Two house painters in hazmat suits remove lead paint from an old house. </span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/two-house-painters-hazmat-suits-removing-458202448?src=vvQkBkUCuohuBPZHOVUaUA-1-5&studio=1">Jamie Hooper/Shutterstock.com</a></span></figcaption></figure><p>Everything is a toxin, or has the potential to be, in the field of toxicology. In the 1500s, Swiss physician <a href="http://doi.org/10.1111/bcpt.12622">Paracelsus, the father of toxicology</a>, coined his famous dictum: “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.” </p>
<p>Lead, however, is toxic at any dose. <a href="https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health">It serves no purpose in our body</a>. Unlike most other toxins that our body can eliminate through metabolism and excretion, our body has <a href="https://www.atsdr.cdc.gov/phs/phs.asp?id=92&tid=22">no ability to purge lead</a>. </p>
<p>As a clinical toxicologist, I care for children and adults who have been exposed to lead and assure that those individuals receive the best possible care. Lead can enter the body through a number of different routes, depending on the source of the element. Most commonly, it enters the body through ingestion or inhalation. </p>
<p>As an example, toddlers are constantly placing items, including their hands, in their mouths. If a toddler lives in an old home that was previously painted with leaded paint – which was <a href="https://www.govinfo.gov/content/pkg/STATUTE-84/pdf/STATUTE-84-Pg2078.pdf">banned in the United States in 1978 for use in homes</a> – the child may ingest old lead paint chips or lead contaminated dust from their hands on a daily basis resulting in gastrointestinal absorption of lead. This is by far one of the most common causes for elevated blood lead level that I see in my clinic. </p>
<p>On the other hand, I have evaluated adults in our clinic who had elevated blood lead levels after inhaling lead vapor following heating of lead in poorly ventilated areas. A couple of those cases included a hobbyist who made his own lead musket balls in his basement for Revolutionary War and Civil War reenactments and a military marksmen who was practicing target shooting with lead ammo. One of my patients who was pregnant was using a heat gun to strip lead paint in an old home and developed markedly elevated blood lead levels via inhalation, placing her fetus at risk since lead crosses the placenta. </p>
<h2>Clinical effects of lead</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=411&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=411&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=411&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=516&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=516&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281218/original/file-20190625-81750-pi8g8s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=516&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 people in areas of Flint, Michigan, were exposed to high levels of lead through the water supply.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/ypsilanti-miusa-jan-27-2016-sign-368463005?src=vvQkBkUCuohuBPZHOVUaUA-1-8&studio=1">Barbara Kalbfleisch/Shutterstock.com</a></span>
</figcaption>
</figure>
<p>The clinical effects from lead toxicity are potentially subtle and may be slow to emerge and may not be noticed initially. The timing of symptoms is based on the dose taken into the body and the time over which lead enters the body. A child who ingests a lead fishing sinker that is retained in the stomach may have a rapid rise in blood lead levels and become symptomatic over days with nausea, vomiting, confusion, and sedation. On the other hand, a child exposed to ingested dust contaminating the hands daily may develop few and subtle symptoms that take years to manifest, if at all. </p>
<p>Once lead enters the body, it first flows through the blood stream where it slowly crosses into various organs such as the kidneys, muscles and brain. Lead is bad for humans because it interferes with numerous enzymes inside the cells of these organs. This results in symptoms such as muscle and joint aches as well as constipation and overall fatigue. It damages our brains by interfering with how brain cells send messages and communicate. Lead decreases fertility in both males and females. It harms our kidneys and can result in <a href="https://ghr.nlm.nih.gov/condition/hypertension">hypertension</a> later in life. Lead prevents our bodies from creating hemoglobin – the molecule that carries oxygen in our red blood cells – resulting in <a href="https://www.nhlbi.nih.gov/health-topics/iron-deficiency-anemia">anemia</a>. </p>
<p>Rather than being eliminated, much of the lead we absorb into our bodies becomes deposited in bones and stays with us for the rest of our lives. From those tissues and the blood, lead will eventually enter the bone where it is deposited and remains for the lifetime of most individuals. That is why the Centers for Disease Control and Prevention has clearly stated that “<a href="https://ephtracking.cdc.gov/showChildhoodLeadPoisoning">no safe blood lead level in children has been identified</a>.” </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/281216/original/file-20190625-81776-np2kee.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/281216/original/file-20190625-81776-np2kee.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=361&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281216/original/file-20190625-81776-np2kee.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=361&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281216/original/file-20190625-81776-np2kee.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=361&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281216/original/file-20190625-81776-np2kee.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=453&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281216/original/file-20190625-81776-np2kee.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=453&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281216/original/file-20190625-81776-np2kee.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=453&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Chelation therapy uses ethylenediaminetetraacetic acid to remove lead, mercury, iron and arsenic from the blood.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/chelation-therapy-lead-mercury-iron-acid-1341184721?studio=1">rumruay/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Lead in the brain</h2>
<p>Lead is a dangerous toxin for people of all ages. But it is especially dangerous for young children. In young developing brains it alters brain development and changes the architecture, ultimately causing learning problems and lower IQs. In the brain lead interferes with with the release of signaling molecules called neurotransmitters, it inhibits function of a receptor (N-methyl-D-aspartate-type glutamate receptor) vital for memory and forming new neural connections, and raises the levels of a messenger molecule called protein kinase C. Taken together, these effects diminish the the number of <a href="https://www.ncbi.nlm.nih.gov/pubmed/9870138">synaptic connections during a critical early period</a> of postnatal development. </p>
<p>There are numerous treatments, such as a process called chelation which helps to eliminate lead from the body when an individual has been poisoned. Chelation is used when blood lead levels are above a specific critical threshold where such treatments might benefit. However, the first goal is to assure our population does not become exposed to toxins, especially lead. </p>
<p>Entities, such as the CDC, the <a href="https://www.osha.com">Occupational Safety and Health Administration</a> and local state health departments work to decrease adult and child lead exposure. Public health initiatives over the past few decades in the U.S. have been successful in <a href="https://www.sciencedirect.com/science/article/pii/S0002934316306003">lowering our public’s blood lead levels</a>. Such public health preventative work to decrease lead exposure will reduce future adverse health outcomes in subsequent generations.</p>
<p>If you have questions about lead, view information at reliable sites, such <a href="http://www.vdh.virginia.gov/leadsafe/">your state health department</a>, <a href="https://www.cdc.gov/nceh/lead/">the CDC</a> and <a href="https://www.atsdr.cdc.gov/ToxProfiles/tp.asp?id=96&tid=22">the Agency for Toxic Substances and Disease Registry</a>. </p>
<p>The U.S. poison centers can also help to answer questions regarding lead poisoning, day or night (1-800-222-1222).</p><img src="https://counter.theconversation.com/content/116506/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher P. Holstege 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>The Flint water crisis made the country aware of the dangers of lead. But why, exactly, is this element so toxic and what does it do to the body?Christopher P. Holstege, Professor of Emergency Medicine and Pediatrics, University of VirginiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/912882018-02-07T00:03:26Z2018-02-07T00:03:26ZHow bombardier beetles survive being eaten – and other amazing animal defence mechanisms<p>In Disney’s film version of Pinnochio, the boy-puppet rescues his creator Geppetto by lighting a fire inside Monstro the whale, who has swallowed them both. The fire causes the whale to sneeze, freeing Pinnochio and Geppetto from their gastric prison.</p>
<p>Before you dismiss this getaway as incredible fantasy, consider that new research shows that a kind of fire in the belly can actually be an effective strategy for escaping predators in the real world. In fact, the animal kingdom is full of amazing examples of unusual defence mechanisms that help small creatures avoid a nasty fate.</p>
<p>In a new paper <a href="http://rsbl.royalsocietypublishing.org/lookup/doi/10.1098/rsbl.2017.0647">in Biology Letters</a>, scientists at Kobe University in Japan describe how bombardier beetles can survive being eaten by a toad by releasing a hot chemical spray that makes the hungry amphibian vomit.</p>
<p>Bombardier beetles are so-named because, when threatened, they emit a boiling, irritating substance from their backsides <a href="http://news.bbc.co.uk/2/hi/science/nature/422599.stm">with remarkable accuracy</a>, to deter potential predators. They produce the caustic mixture by <a href="https://www.wired.com/2014/05/absurd-creature-of-the-week-bombardier-beetle/">combining hydrogen peroxide, hydroquinones and chemical catalysts</a> in a specially reinforced chamber at the base of their abdomen, which shields the beetle’s own organs from the resulting explosive reaction.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/iPlcA3VGXtc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p><a href="http://rsbl.royalsocietypublishing.org/lookup/doi/10.1098/rsbl.2017.0647">The Japanese researchers</a> fed two different species of bombardier beetles to captive toads. They were then able to confirm that the beetles used their weapon inside the toads by listening carefully for the explosive pop that accompanies each discharge. </p>
<p>Toads are ambush predators, quite used to swallowing first and asking questions later. When they start to feel a dose of diner’s remorse, they can literally turn <a href="https://indianapublicmedia.org/amomentofscience/how-to-heave-your-guts/">their stomachs inside out and scrape out the contents</a>, rather than suffering meekly from indigestion. Many of the toads in this experiment did just that, disgorging the beetles up to 107 minutes after ingestion. Remarkably, the ejected beetles all survived.</p>
<p>In a further experiment, the researchers poked beetles with forceps to deplete their spray reserves. Compared to those with full tanks of fuel, the exhausted beetles were much less likely to be ejected. This showed that it really was their chemical arsenals that saved them, rather than just their taste or behaviour in the gut.</p>
<figure> <img src="https://media.giphy.com/media/26DN4S3rQgsgvzEY0/giphy.gif"><figcaption>“I guess I’ll die another day.” Sugiura & Sato, Kobe University</figcaption></figure>
<p>The bombardier beetle is of course not the only animal escape artist. The diverse getaway tactics of animals are a testament to the fascinating creativity of evolution. Subject to millions of years of abuse and exploitation by predators, natural selection has shaped an array of ingenious strategies for cheating death in the face of would-be devourers.</p>
<h2>Animal Houdinis</h2>
<p>Some examples are probably familiar to most people. For instance, many lizards drop their tails to distract a predator or <a href="https://academic.oup.com/bioscience/article/59/8/728/256547">escape from its venom</a>. But others are more exotic. Sea cucumbers don’t have tails so they <a href="http://echinoblog.blogspot.ca/2012/01/sea-cucumber-evisceration-defense.html">eject and regenerate their internal organs instead</a>. Loud sounds (<a href="http://thatslifesci.com.s3-website-us-east-1.amazonaws.com/2016-12-26-How-Pistol-Shrimp-Kill-With-Bubbles-AStrauss/">such as the “gunshots” of snapping shrimp</a>) and bright colours (as on <a href="https://www.ucpress.edu/ebook.php?isbn=9780520952461">banded wing grasshoppers</a>) are also effective means of <a href="https://pdfs.semanticscholar.org/5742/afd010a4e1b889d1097f28f6f5741f10d33e.pdf">startling predators</a>. Mantid insects unite movement, sound and colour in an elaborate display that can stop an attack or at least give them a chance to escape.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/G6QBRbLrOSw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>Some animals fight back, such as the frogs that can <a href="http://rsbl.royalsocietypublishing.org/content/4/4/355">erect sharp bony splinters</a> from their claws that <a href="https://www.newscientist.com/article/dn13991-horror-frog-breaks-own-bones-to-produce-claws/">pierce their own skin</a>, like X-Men’s Wolverine. Other animals, including <a href="https://doi.org/10.1098%252Frspb.2001.1708">the mimic octopus</a>, prefer to pretend to be being dangerous, <a href="https://www.nature.com/scitable/blog/accumulating-glitches/the_mimic_octopus_master_of">adopting the appearance of more deadly prey</a> when threatened.</p>
<p>The stunning variety of defensive mechanisms would be impressive even if we only counted variations of chemical warfare, similar to the bombardier beetle’s steam treatment. There are the defensive toxins in <a href="https://www.nationalgeographic.com/animals/fish/group/pufferfish/">pufferfish</a> and <a href="http://www.bbc.com/earth/story/20150422-the-worlds-most-poisonous-animal">poison arrow frogs</a>, the nauseating <a href="https://www.newscientist.com/article/mg12717282-900-science-the-seven-deadly-smells-of-a-skunk/">odours of skunks</a>, the charmingly named but actually revolting <a href="http://www.bbc.com/earth/story/20150623-millipedes-use-chemical-weapons">repugnatorial glands of some millipedes</a>, and the <a href="http://www.nydailynews.com/life-style/vomit-bird-throws-defense-predators-eurasian-roller-nestlings-emit-foul-smelling-fluid-protection-article-1.1037423">projectile vomiting</a> and <a href="https://wildfowl.wwt.org.uk/index.php/wildfowl/article/view/562">faecal egg decorating</a> of some birds.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/205061/original/file-20180206-14107-1lzimnd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205061/original/file-20180206-14107-1lzimnd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205061/original/file-20180206-14107-1lzimnd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205061/original/file-20180206-14107-1lzimnd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205061/original/file-20180206-14107-1lzimnd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205061/original/file-20180206-14107-1lzimnd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205061/original/file-20180206-14107-1lzimnd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">I wouldn’t eat me if I were you.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/strawberry-poison-dart-frog-dendrobates-pumilio-110478725?src=wsqFvxedepyW5_6CPNI-NQ-1-3">Maiquez/Shutterstock</a></span>
</figcaption>
</figure>
<p>Why should nature have created such an impressive array of defensive tactics? One possible explanation can be summarised as the <a href="http://evosophos.com/life-dinner-principle/">life-dinner principle</a>, articulated by biologists <a href="http://rspb.royalsocietypublishing.org/content/205/1161/489">Richard Dawkins and John Krebs in the late 1970s</a>. The argument is that predator and prey often face asymmetrical selection pressures, meaning that the stakes are different for the two competitors. If a predator fails to capture its target, it loses dinner, but if the prey fails to escape, it loses its life. Because the stakes are greater for prey, we shouldn’t be surprised they have developed so many impressive defences.</p>
<p>Understanding nature’s tremendous capacity to adapt should make us be careful. Humans interact with other organisms all the time, and usually we’re the predators. When we try to take action against other creatures to stop them spreading disease or eating crops, we should be mindful that evolutionary innovation can produce remarkable adaptations. For example, our widespread use of <a href="https://www.myjoyonline.com/lifestyle/2018/february-3rd/high-levels-of-antibiotic-resistance-found-worldwide-who.php">antibiotics</a> and <a href="https://guardian.ng/features/malaria-cases-rise-as-insecticide-resistance-spreads/">pesticides</a> has spurred the evolution of organisms that are resistant to these methods.</p>
<p>Only by having a healthy respect for the relentless power of evolution can we hope to generate sustainable solutions to these kinds of problems. If we grow complacent and inattentive, we may some day soon find ourselves facing newly evasive diseases and pests, sputtering to breathe and dyspeptic amid all the fire and smoke in our bellies.</p><img src="https://counter.theconversation.com/content/91288/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Luc Bussiere 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>Meet the brawny bug with a concoction so caustic it’ll make a toad vomit.Luc Bussiere, Lecturer in Biological Sciences, University of StirlingLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/508422016-01-13T19:11:00Z2016-01-13T19:11:00ZLittle shop of horrors: the Australian plants that can kill you<figure><img src="https://images.theconversation.com/files/106215/original/image-20151216-25624-1lovqtc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The national flower of Zimbabwe, the Glory Lily, is also found in Queensland where it's more famously known as a noxious weed that's highly poisonous to humans.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/johnske/8213403234/in/photolist-dUdxyR-7BZFmg-2kumWS-PfzQp-PfDUV-2iXTMq-ZqCUH-2c5zYC-ip2C6s-xtDaA-q6duat-dvMQCA-9ZyxfF-9akoSc-8jQzaX-931xu7-iWrEJE-4oVSA9-db4SpL-22fiwC-6VEJJn-6mS577-2jD21h-2duVi6-NYPC2-8HiWgF-Sweeh-dugbVG-hV5Y21-6itcVH-21jbQN-Swe9S-hpy1zn-981EdA-TiXYa-YtLW9-6NuXJA-6NuWsd-9xVKgH-od8ktK-qa8htf-9ex8am-9yst5k">JohnSkewes/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Australia is so famous for its dangerous creatures that visitors often arrive fearful that everything that moves is out to get them. In a land where snakes, spiders, shells and even one of the iconic mammals – the platypus – can bite or sting, should we all be worried about plants as well? </p>
<p>Plants around the world produce a staggering diversity of chemicals and many of these are potentially toxic to animals including humans, sometimes even upon contact. Many of these toxins have evolved to protect plant roots, leaves and unripe fruits from being eaten by herbivores, particularly insects and browsing mammals. </p>
<p>Australia’s toxic plants are not terribly appealing or nutritious for humans. If someone is poisoned, it’s usually accidental, and <a href="http://www.schn.health.nsw.gov.au/parents-and-carers/fact-sheets/poisonous-plants">many victims are curious children</a>. </p>
<p>There are <a href="http://anpsa.org.au/APOL7/sep97-4.html">many historical records</a> of plant poisoning in Australia involving early explorers and settlers who were short of supplies or looking for new sources of food. Today, though, plant poisoning accounts for <a href="http://www.austin.org.au/Assets/Files/VPIC%20Annual%20Report%202014.pdf">less than 1% of calls</a> to poisons information lines in Australia. </p>
<h2>Animals beware</h2>
<p>The threat of poisoning to livestock is <a href="http://www.mla.com.au/Research-and-development/Animal-health-welfare-biosecurity/Poisonings/Toxic-plants">much more substantial</a> and causes significant economic and animal welfare impacts. </p>
<p>It’s in the interests of cattle and sheep to become expert botanists, but even experts can get things wrong when confronted with something they’ve never seen before. Most livestock poisonings occur when animals are moving through new country or are put into new paddocks with unfamiliar plants.</p>
<p>Native plants that kill significant numbers of livestock include Cooktown ironwood in northern Australia (as little as 50 grams of leaf can contain a quantity of alkaloids that can kill a bull) and the poison peas and heart-leafed poison bush of Western Australia and Queensland respectively (<em>Gastrolobium</em>), which contain a deadly metabolic poison, sodium fluoroacetate.</p>
<p>Elsewhere, introduced pasture weeds such as fireweed, <em>Senecio madagasciarensis</em>, and Paterson’s curse, <em>Echium plantagenium</em>, pose significant threats to cattle, sheep and horses.</p>
<h2>It’s in the dose</h2>
<p>The adage that “the poison is in the dose” is correct in that small amounts of most poisonous plants are unlikely to cause permanent damage or death, although there are exceptions. Indeed, most herbivores have to tolerate some exposure to plant poisons because they’re so widespread among the plants they eat. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/108120/original/image-20160114-2365-yr2vsl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/108120/original/image-20160114-2365-yr2vsl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=2058&fit=crop&dpr=1 600w, https://images.theconversation.com/files/108120/original/image-20160114-2365-yr2vsl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=2058&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/108120/original/image-20160114-2365-yr2vsl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=2058&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/108120/original/image-20160114-2365-yr2vsl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=2586&fit=crop&dpr=1 754w, https://images.theconversation.com/files/108120/original/image-20160114-2365-yr2vsl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=2586&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/108120/original/image-20160114-2365-yr2vsl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=2586&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Small amounts of some toxic compounds can even be beneficial and sometimes have traditional or medical uses. Aboriginal people, for instance, used <em>Duboisia hopwoodii</em> and other native tobacco species (<em>Nicotiana</em>) to produce a powerful and widely traded stimulant, pituri, the active ingredient of which is the potent alkaloid, nicotine. </p>
<p>Similarly, atropine, an alkaloid found in Angels’ trumpets and thorn-apple (<em>Brugmansia</em> and <em>Datura</em> species) is a powerful hallucinogen and toxin. But it’s also a valuable drug used to treat some heart and nervous conditions, as well as poisoning by some other plant alkaloids and cardiac glycosides. </p>
<p>Knowing what dose of poison a plant contains is not always easy. How much toxin an individual plant contains can vary with season, the age of the plant, soil type, drought and the plant’s genes. Just as you may be tall and your next-door neighbour short, two plants of the same species growing alongside can vary in how much toxin they produce. </p>
<p>On top of that, different animal species and individual people and animals can also vary in their ability to tolerate poisons. This makes ingesting toxic plants a little like Russian roulette: there’s a strong element of chance.</p>
<h2>Deadly relatives</h2>
<p>A significant number of Australia’s more than 20,000 plants are potentially toxic. In many cases, Australia has species or subspecies of plants that are closely related to well-known toxic plants from elsewhere. But their relative toxicity is not well established. </p>
<p>The Indian suicide tree, <em>Cerbera odollum</em>, has been described as the “<a href="https://www.newscientist.com/article/dn6701-suicide-tree-toxin-is-perfect-murder-weapon/">perfect murder weapon</a>”, for instance, but the toxicity of our native <em>Cerbera manghas</em> is less well understood, despite the fact it possesses the same cardiac poisons. </p>
<p>Similarly, how our native strychnine bushes <em>Strychnos lucida</em> and <em>S. psilosperma</em> compare to the better-known strychnine tree <em>S. nux-vomica</em> from India is not well known, but they do also produce strychnine. </p>
<p>Unless you’re a hungry ruminant, you’re probably unlikely to suffer death by plant poisoning in Australia, but the risk is nonetheless real. It pays to realise that garden plants and even common indoor plants are sometimes just as dangerous as what lurks in the bush. Parents and outdoorsy types should be aware of the risks posed by contact with or ingestion of plants.</p>
<p><em>This article is part of our series <a href="https://theconversation.com/au/topics/deadly-australia">Deadly Australia</a>. Stay tuned for more pieces on the topic in the coming days.</em></p><img src="https://counter.theconversation.com/content/50842/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ben Moore receives funding from the Australian Research Council. </span></em></p>It’s not just Australia’s animals that can be deadly, there are plenty of dangerous plants too.Ben Moore, Senior Lecturer in Ecology, Hawkesbury Institute for the Environment, Western Sydney UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/429962015-06-10T02:01:24Z2015-06-10T02:01:24ZWhy I Love: surrounding myself with venomous critters<figure><img src="https://images.theconversation.com/files/84457/original/image-20150609-10747-1t852o5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Stephens' banded snake is one of Australia's few arboreal (tree-dwelling) venomous snakes.</span> <span class="attribution"><span class="source">Timothy Jackson</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Life is chemistry. You, me and every living thing – we’re all just spectacularly complex chemistry sets. Inside you, every second of the day, thousands of tiny chemical reactions are taking place. </p>
<p>Chemical reactions powered your transformation from a single cell into a colony of trillions of cells, and they allow you to harvest energy from the environment and transform it into yet more cells. They maintain the delicate balance in which all the components of your body function. In fact, they are that balance. They even drive your thoughts and emotions. </p>
<p>Most of these molecules have evolved to work <em>inside</em> the bodies of the organisms that make them. But some are special: some have evolved to work on the <em>outside</em>, often in the bodies of other organisms. These are the “exochemicals”, “exo” meaning outside, as opposed to “endo”, meaning inside. </p>
<p>Ever since there has been an inside and an outside – ever since cells evolved the first membranes that segregated their chemicals from those of the outside world – there has been “exochemistry”. </p>
<p>The first cells fed by secreting enzymes across their cell walls (to the outside) in order to break down large molecules into smaller bite-size chunks that could be then absorbed. </p>
<p>Today, exochemistry is all around us: organisms of all kinds use chemicals to send signals to one another, poisonous plants and animals use them to deter would-be predators or competitors, and venomous animals use them to secure a meal. </p>
<p>And I’m an exochemist – I research this chemistry “on the outside”.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=583&fit=crop&dpr=1 600w, https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=583&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=583&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=733&fit=crop&dpr=1 754w, https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=733&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/84465/original/image-20150609-10675-m0bq0i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=733&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 cane toad uses poison to defend itself from would-be predators, with devastating consequences for native Australian wildlife.</span>
<span class="attribution"><span class="source">Timothy Jackson</span></span>
</figcaption>
</figure>
<h2>Day in the life</h2>
<p>The evolution of snake venom is currently the primary focus of my research. Venoms are mixtures of toxins, which are physiologically active molecules that have evolved to disrupt the internal chemistry (the “endochemistry”) of target animals. </p>
<p>Using fangs, stingers or other specialised apparatuses, venomous animals inject these weaponised chemical cocktails into their intended prey, or into potential predators trying to make them into prey. This is textbook exochemistry in action.</p>
<p>There are many ways to study venom. But first I need to get my hands on some. Although I’ve spent many years working directly with venomous animals, these days I prefer to keep my hands away from the bitey parts and I leave the venom collection to the specialists at <a href="http://www.venomsupplies.com">Venom Supplies</a>. </p>
<p>Before I get my venom, I also need to think about the questions I want to ask. Studying the evolution of venom, like most areas of science, is hypothesis-driven research. This means we proceed by coming up with specific predictions and then conduct experiments to try and confirm or deny their accuracy. So, the predictions I want to test often dictate which venoms I need to acquire. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=391&fit=crop&dpr=1 600w, https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=391&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=391&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=492&fit=crop&dpr=1 754w, https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=492&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/84464/original/image-20150609-10675-luuzb9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=492&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 funnel web spider uses its impressive fangs to deliver venom both in offence and defence.</span>
<span class="attribution"><span class="source">Timothy Jackson</span></span>
</figcaption>
</figure>
<p>One of the concepts that drives a lot of my research is the predator-prey arms race. A useful way of thinking about this is to think of the venom and the organism into which it is injected as chemical systems with specific functions. </p>
<p>What I mean by “systems” is that each of them is composed of many different parts that work together in order to achieve some specific goal that is selected by evolution. The endochemistry of any given organism is a marvellously complex and finely balanced system that has evolved to keep that organism alive. </p>
<p>Venom is a system designed to disrupt that fine balance. So, when exochemistry and endochemistry meet, it’s chemical warfare. What I’m interested in is how evolution gives one system the edge over another. </p>
<p>I’ll often start by just looking at the composition of the venom, such as seeing what toxins are present. I’ll then correlate this with what is known about the snake’s diet, and how it catches its prey. </p>
<p>Now the fun begins as I attempt to disentangle the details of interaction between the two systems. All sorts of complexities emerge: which systems in the prey animal does this venom attack? Maybe the blood or the nervous system? Are there molecules in the venom that, while not toxic themselves, facilitate the action of the toxins? Is the prey animal evolving resistance? Is the prey animal active or at rest when the snake attacks it? All of these questions and many more arise when studying the evolution of venom.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=365&fit=crop&dpr=1 600w, https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=365&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=365&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=459&fit=crop&dpr=1 754w, https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=459&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/84460/original/image-20150609-10747-2dy71w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=459&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 golden-crowned snake specialises in feeding upon lizards. How might this affect the composition of its venom?</span>
<span class="attribution"><span class="source">Timothy Jackson</span></span>
</figcaption>
</figure>
<h2>Beyond chemistry</h2>
<p>Exochemistry is not any one field. For example, the study of toxins produced by plants and animals is called toxinology, where we study everything from the genes that encode the toxins and their targets to the structure and function of the molecules themselves, all the way up to the sorts of systems-level questions I mentioned above. </p>
<p>Insights from toxinological research are important not only for our understanding of the evolution of life on Earth, but also have many applications in human medicine. Studying the structure and function of toxins has given us great insight into our own physiology. It has helped us understand the nervous system and disorders of <a href="http://en.wikipedia.org/wiki/Coagulation">blood clotting</a>. </p>
<p>Another major area of exochemical research is biodiscovery, where toxins are sought to aid in the creation of life-saving drugs and pesticides to protect our crops. Understanding venoms is also crucial for the development of antivenoms, as snakebite is a major medical issue in developing countries. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/84462/original/image-20150609-10672-itye7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Before the development of an effective antivenom, the human fatality rate from bites by death adders may have been as high as 50%.</span>
<span class="attribution"><span class="source">Timothy Jackson</span></span>
</figcaption>
</figure>
<p>For someone like me studying the evolution of exochemistry, the natural world is an inexhaustibly rich source of stimulating research questions. </p>
<p>Everywhere I look I see chemical arms races. All around us are poisonous and venomous critters taking advantage of whatever chemical leg-up they can exploit to get that critical competitive edge in the struggle for survival. </p>
<p>As one organism gets ahead, evolving a new chemical weapon, so another evolves a degree of resistance to that weapon, and yet another, perhaps incapable of making its own, steals that weapon (a process called toxin sequestration) and uses it to further its own cause. </p>
<p>For some people, being surrounded by venomous creepy crawlies probably seems like a nightmare, but for me it’s a dream come true.</p><img src="https://counter.theconversation.com/content/42996/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Timothy N. W. Jackson 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>Most people avoid venomous creatures, but they can also teach us a lot about chemical reactions that take place outside of the body - or exochemistry.Timothy N. W. Jackson, PhD candidate in exochemistry, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.