tag:theconversation.com,2011:/id/topics/food-safety-3481/articlesFood safety – The Conversation2024-03-29T08:28:44Ztag:theconversation.com,2011:article/2263692024-03-29T08:28:44Z2024-03-29T08:28:44ZHow to make sure your leftovers are safe to eat<figure><img src="https://images.theconversation.com/files/584372/original/file-20240326-20-oixbu7.jpg?ixlib=rb-1.1.0&rect=15%2C7%2C5144%2C3435&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Leftovers should only be stored in the fridge for a maximum of two days.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/handsome-man-putting-lunchbox-fridge-taking-2399269457">Halfpoint/ Shutterstock</a></span></figcaption></figure><p>Eating leftovers can be a great way to save money, diversify your cooking repertoire and reduce food waste. </p>
<p>But eating leftover food can also be risky as these foods have already been exposed to bacteria in the environment. If you haven’t stored and re-heated leftovers correctly, you could be putting yourself at risk of potentially life-threatening food poisoning.</p>
<p>That doesn’t mean you should start avoiding leftovers, however. By following the the correct <a href="https://www.foodstandards.gov.scot/consumers/food-safety/at-home/storage">food safety practices</a>, you can ensure you avoid harm when eating leftovers. </p>
<h2>How quickly should leftovers be refrigerated or frozen?</h2>
<p>Bacteria exist everywhere in our world, including in kitchens – and the foods within them. The bacteria that cause food to spoil can grow rapidly with the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10325786/">right nutrients, moisture and temperatures</a>. Some double in numbers in as little as 20 minutes.</p>
<p>It’s important that any leftovers are put into the fridge or freezer as quickly as possible and within two hours maximum. This time advice is based on how quickly bacteria can grow in food at non-refrigerated temperatures, and means leftover food become less safe to eat the longer it is left at more than 5°C. You should also make sure that leftovers are covered. Clingfilm and airtight lids help prevent air from getting at the food. This is important, as most pathogens <a href="https://www.britannica.com/science/bacteria/Physical-requirements">need oxygen to grow</a>.</p>
<h2>How long are refrigerated leftovers safe to eat?</h2>
<p>Your fridge should be kept at a temperature of <a href="https://ask.usda.gov/s/article/Why-is-a-refrigerator-important-for-keeping-food-safe">between 0 and 5°C</a>, as this inhibits the growth of food poisoning bacteria on leftovers. </p>
<p>Leftovers must be eaten within two days, as any longer gives harmful bacteria more time to grow. Indeed, pathogens such as <em>Listeria</em>, which can cause flu-like symptoms, <a href="https://ask.usda.gov/s/article/Why-is-a-refrigerator-important-for-keeping-food-safe">can even grow</a> in <a href="https://pubmed.ncbi.nlm.nih.gov/3146567/">refrigerated temperatures</a> and are more likely to grow beyond two days – which is why this is the recommended time limit for storing your leftovers.</p>
<p>If you don’t think you’ll eat your leftovers within that timeframe, consider freezing them. Leftovers can be kept for <a href="https://www.foodstandards.gov.scot/consumers/food-safety/at-home/storage">up to three months</a> if frozen at -18°C.</p>
<h2>What is the safest way to re-heat your leftovers?</h2>
<p>When you reheat leftovers, you must <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742775/pdf/foods-06-00107.pdf">ensure the food is piping hot</a> all the way through. If not, don’t eat it.</p>
<p>Leftover foods should be reheated to an internal temperature of <a href="https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/leftovers-and-food-safety">at least 165°F</a> (74°C). For sauces, stews, soups and gravy, it’s best to bring them to a full boil, stirring for at least three minutes. These practices will kill most bacteria and inactivate any heat-sensitive bacterial toxins that are present. </p>
<p>If reheating leftovers in the oven, set the oven temperature to at least 325°F (163°C or gas mark 3) and bake long enough to completely heat the food through to at least 74°C. If reheating leftovers in the microwave, you should also make sure they reach an internal temperature of 74°C before eating.</p>
<figure class="align-center ">
<img alt="A woman places a bowl in the microwave to reheat." src="https://images.theconversation.com/files/584373/original/file-20240326-22-rfg43i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/584373/original/file-20240326-22-rfg43i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/584373/original/file-20240326-22-rfg43i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/584373/original/file-20240326-22-rfg43i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/584373/original/file-20240326-22-rfg43i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/584373/original/file-20240326-22-rfg43i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/584373/original/file-20240326-22-rfg43i.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">
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<span class="caption">Make sure leftover foods are piping hot when you reheat them.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/african-woman-reheat-food-ceramic-bowl-1884606334">TommyStockProject/ Shutterstock</a></span>
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<p>Reheating food using a slow cooker is not a good idea because if foods stay at a temperature less than 165°F for several hours, this can <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742775/pdf/foods-06-00107.pdf">permit bacterial growth</a> – increasing your risk of food poisoning.</p>
<h2>Can you reheat leftovers more than once?</h2>
<p>You really should not reheat leftovers <a href="https://webarchive.nationalarchives.gov.uk/ukgwa/20190801131631/https://www.food.gov.uk/sites/default/files/media/document/sfbb-childminders-cooking-reheating.pdf">more than once</a>. Each time a food warms and cools, it provides the right temperature and amount of time needed for any harmful bacteria to start to re-grow.</p>
<p>This then makes it harder for heat kill all the pathogens present the next time you warm up the leftovers. If you don’t think you’ll eat all your leftovers within two days, consider freezing them.</p>
<h2>Can you reheat a takeaway?</h2>
<p>Whether you can safely re-heat takeaway foods depends on how you stored it. </p>
<p>If it was stored warm in the back of your car or left at room temperature in your home for more than two hours, then the meal may be a food poisoning risk – especially if you’ve already touched or partially eaten it (which introduces bacteria to the food). </p>
<p>But if you didn’t handle the food much and refrigerated it within two hours of purchase, then the takeaway is safe to re-heat – provided the next time it’s eaten it’s first heated to a piping hot temperature of at least 74°C. It also shouldn’t be stored in the fridge for more than two days. </p>
<p>There are some takeaway foods that you should be careful about saving as leftovers. Cooked rice dishes are possibly the most risky to save. Uncooked rice may contain spores of <em><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7913059/pdf/foods-10-00302.pdf">Bacillus cereus</a></em>, a bacterium that causes food poisoning. </p>
<p>While the parent bacterium is killed when rice is cooked, its spores can survive the temperature of boiling water. If rice is not refrigerated within two to three hours of cooking, the spores can grow into bacteria which in turn release the rice toxins which give rise to food poisoning symptoms such as diarrhoea, abdominal pain and vomiting. The longer contaminated cooked rice is left to stand at a non-refrigerated temperature, the more <em>Bacillus cereus</em> will be present and the more unsafe the dish becomes.</p>
<p>If cooked rice needs to be saved, it should be covered once cooked and cooled quickly (ideally within 2 hours), then stored and refrigerated for no more than 24 hours. <a href="https://www.nhs.uk/common-health-questions/food-and-diet/can-reheating-rice-cause-food-poisoning/">Cooked rice leftovers</a> should be piping hot when reheated, and should never be reheated more than once. </p>
<p>Leftovers can be safe to eat so long as you take the right precautions. But if you’re ever in doubt, or don’t think you’ll eat them within two days, storing them in the freezer will give you more flexibility than storing them in the fridge.</p><img src="https://counter.theconversation.com/content/226369/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Primrose Freestone 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>If leftovers aren’t saved and reheated properly, it could put you at risk of food poisoning.Primrose Freestone, Senior Lecturer in Clinical Microbiology, University of LeicesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2257002024-03-27T16:02:40Z2024-03-27T16:02:40ZHazardous mould contaminates many food staples – what you should know about mycotoxins<p><em>Mycotoxins are substances produced by mould that poison food. They are <a href="https://academic.oup.com/carcin/article/31/1/71/2392129">harmful</a> to humans and animals when consumed. According to the Food and Agricultural Organisation (FAO), about 25% of the world’s agricultural harvests are <a href="https://pureadmin.qub.ac.uk/ws/files/185127566/Worldwide_contamination_of_food_crops_with_mycotoxins_Validity_of_the_widely_cited_FAO_estimate_of_25.pdf">contaminated</a> by mycotoxins. Though reliable data is lacking, mycotoxin contamination is <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4108760/">widespread in Africa</a>. It often takes the form of aflatoxin in cereal crops and has led to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6354945/#:%7E:text=They%20have%20the%20ability%20to,of%20humans%20annually%20(15).">health issues</a> such as chronic gastritis, diarrhoea, kidney problems and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3699030/">liver cancer</a>. Biologist Oluwadara Pelumi Omotayo <a href="https://www.sciencedirect.com/science/article/pii/S2214750018307315">studied</a> how mycotoxins contaminate ginger in South Africa. We asked her to explain what they are and how to avoid the danger.</em></p>
<hr>
<h2>What are mycotoxins?</h2>
<p>Mycotoxins are hazardous substances produced by certain microorganisms called toxigenic fungi (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4108760/">moulds</a>). </p>
<p>One mould species may produce more than one type of mycotoxin, and a single mycotoxin may be produced by several mould species. Mycotoxins are ubiquitous. They can be found indoors and outdoors, thriving in warm and highly humid areas. They are usually toxic to living things. </p>
<p>Contamination can lead to variety of illnesses, and even death. They can cause <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4108760/">cancer</a>, <a href="https://www.sciencedirect.com/science/article/abs/pii/B9780323870313000305">hepatic diseases</a>, deterioration of the <a href="https://journals.sagepub.com/doi/abs/10.1191/0960327103ht328oa">kidneys</a>, <a href="https://journals.sagepub.com/doi/abs/10.1191/0960327103ht328oa">nephropathy</a>, and <a href="https://core.ac.uk/download/481757543.pdf">alimentary toxic aleukia</a>, a potentially fatal illness marked by nausea, vomiting, diarrhoea and skin inflammation. They can also impair an animal’s immune system, decrease milk production, cause stunted growth and weight loss, and induce gastroenteritis. </p>
<p>Mycotoxins have been reported to be responsible for numerous human deaths. For example, in 2004, Kenya <a href="https://www.devex.com/news/kenyans-love-maize-but-aflatoxins-are-making-it-dangerous-96279">recorded</a> an outbreak of aflatoxin poisoning which led to the death of about 125 people.</p>
<p>Mycotoxins drastically suppress the immune system. And a single mycotoxin, even in minute quantities, can result in acute poisoning in humans and animals.</p>
<p>Over 300 types of mycotoxins have been identified so far, including the notable aflatoxin and other types like ochratoxin and fumonisin, which often contaminate grains like maize. </p>
<h2>How do humans come in contact with mycotoxin?</h2>
<p>People can be exposed to mycotoxins through eating contaminated food and through contact and absorption through the skin. Exposure can also happen through inhalation of polluted air, as they can be present in airborne particles such as fungal spores.</p>
<p>Human exposure to mycotoxins can come from plant-based food and from the carry-over of mycotoxins and their metabolites in animal products such as meats.</p>
<p>Food items that can be tainted include spices, grains (such as maize, rice and sorghum), nuts, fruits (dry or fresh), coffee beans, cocoa seeds, vegetables and rhizomes like ginger.</p>
<h2>Why should we be concerned about mycotoxins?</h2>
<p>Mycotoxin contamination is widespread, especially in African countries. The toxins exist even in medicinal plants and herbs. This was confirmed by our <a href="https://www.sciencedirect.com/science/article/pii/S2214750018307315">study</a>, which investigated the presence of mycotoxin in ginger. </p>
<p>Ginger has been used since antiquity for the treatment of various ailments such as colds, migraines and gastrointestinal tract disorders. However, like other spices and herbs, it has been reported to contain mycotoxins. Ginger has been found to contain aflatoxin and ochratoxin A (which is known to be teratogenic: capable of causing developmental abnormalities in unborn foetuses). </p>
<p>From our study, aflatoxins B1, B2, G1 and G2 and ochratoxin A were found in ginger collected from the North-West province of South Africa in summer and winter. Though at varying concentrations, the highest concentration was observed in summer. This indicates that there’s no period when crops and plants, including ginger, would necessarily be completely free from mycotoxins.</p>
<h2>How do farmers and consumers know that a crop has been contaminated?</h2>
<p>Mycotoxins are not visible to the naked eye. The invasion of crops and foods by moulds is an indication that they are potentially contaminated with mycotoxins. </p>
<p>Farmers and consumers should inspect food crops for evidence of moulds, and discard crops and food that have mould growth. </p>
<h2>What can be done to prevent mycotoxin contamination?</h2>
<p>To minimise the risk of mycotoxin exposure and contamination, we recommend action before and after harvest and storage.</p>
<ul>
<li><p>Prevent mycotoxin/fungi invasion while the crops are still in the field. This can be achieved by cultivating and harvesting at the appropriate time. Adopt techniques that reduce stress in plants, such as ensuring they get enough water and are well spaced. They also need adequate sunlight and should be cultivated on suitable soil. It is also important to avoid using agricultural residues as compost as they can produce toxigenic fungi and mycotoxins when decaying.</p></li>
<li><p>After harvest, reduce fungal contamination and mycotoxin production in foods during storage, handling, processing and transport. Facilities should be monitored and kept at temperatures that discourage mould growth. Crops with moulds should be sorted and removed before storage. Storage facilities must be aerated and dry. Reducing moisture content in crops before storage is important to prevent mould.</p></li>
<li><p>Avoid damage to grains before storing as damaged grain is more susceptible to mould growth and mycotoxin contamination.</p></li>
<li><p>Don’t store food too long before consumption. It is important to follow recommended guidelines for safely storing <a href="https://www.foodsafety.gov/food-safety-charts/cold-food-storage-charts">cooked and raw food</a> in the <a href="https://www.foodsafety.gov/food-safety-charts/food-safety-during-power-outage">refrigerator</a>, <a href="https://www.agric.wa.gov.au/fruit/storage-fresh-fruit-and-vegetables?nopaging=1">fruits and vegetables</a>, <a href="https://wholegrainscouncil.org/recipes/cooking-whole-grains/storing-whole-grains">grains</a>, <a href="https://wildlyorganic.com/blogs/recipes/how-long-do-nuts-last-tips-for-storing-nuts-and-seeds">nuts and seeds</a>, and spices such as <a href="https://eatbydate.com/other/spice-menu/how-long-does-ginger-last-shelf-life/">ginger</a>. </p></li>
<li><p>Inspect and discard foods contaminated by moulds. </p></li>
<li><p>Ensure contaminated foods are not sold to consumers.</p></li>
<li><p>Improve awareness about mycotoxin contamination.</p></li>
</ul><img src="https://counter.theconversation.com/content/225700/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Oluwadara Pelumi Omotayo 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>Mycotoxins contamination causes health issues. Paying attention to storage of agricultural produce can save many lives.Oluwadara Pelumi Omotayo, Postdoctoral Research Fellow, North-West UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2205072024-02-08T14:09:18Z2024-02-08T14:09:18ZNigeria’s street food: tasty but toxic? Expert shares advice to make it safer<p>In the lively streets of Nigeria’s cities, where delicious street food is a daily delight, a wide variety of food can be bought and consumed instantly. From the sizzling suya snack in Abuja to the aromatic jollof rice in Lagos, street food has become an integral part of Nigerian life. </p>
<p>However, beneath these enticing flavours lies a critical question of public safety and health regulation. There is growing concern about the chemical and microbiological safety of these foods, as there seems not to be any oversight or control in their production and marketing.</p>
<p>Over 70% of urban dwellers in Africa <a href="https://www.ifpri.org/blog/why-brutalizing-food-vendors-hits-africas-growing-cities-where-it-hurts#:%7E:text=Food%20markets%20in%20the%20informal,meat%2C%20fish%2C%20and%20milk.">rely on street vendors</a>. However, inadequate government regulation in developing nations, such as Nigeria, raises concerns about food safety and public health. Foodborne diseases have been <a href="https://www.tandfonline.com/doi/full/10.1080/23311932.2023.2266194">linked</a> with contaminated street foods. Common pathogens include <em>E. coli</em> and <em>Salmonella</em>, which has potential to cause foodborne illnesses such as <a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/gastroenteritis-salmonellosis">gastroenteritis</a>, <a href="https://www.who.int/news-room/fact-sheets/detail/e-coli">haemorrhagic colitis or bloody diarrhoea and life-threatening conditions such as haemolytic uraemic syndrome</a>. Heavy metal contamination is another risk. </p>
<p>This issue is not unique to Nigeria or Africa; it is a <a href="https://link.springer.com/chapter/10.1007/978-981-15-2556-8_7">global challenge</a> in many developing countries where street food is a <a href="https://www.scirp.org/journal/paperinformation?paperid=104389">substantial</a> part of the economy.</p>
<p><a href="https://core.ac.uk/download/pdf/82316865.pdf">Research</a> has explored the role of street-vended foods in meeting socio-economic challenges, particularly in developing nations. Other studies have focused on the microbiological safety of street foods (for example, <a href="https://www.sciencedirect.com/science/article/pii/S0362028X22104229?via%3Dihub">soy wara</a>, a Nigerian curdled soy milk product), and <a href="https://core.ac.uk/download/pdf/82316865.pdf">the risk factors in street food practices</a>. </p>
<p>Our own <a href="https://www.tandfonline.com/doi/full/10.1080/23311932.2023.2266194">study</a> analysed gaps in the safety and regulation of street foods in Nigeria. We highlighted gaps in infrastructure, training and vendor awareness, and made recommendations to solve the problems we identified. </p>
<p>We <a href="https://www.tandfonline.com/doi/full/10.1080/23311932.2023.2266194">found</a> a gap in food safety standards for street-vended foods in Nigeria. While street food vendors <a href="https://www.ajol.info/index.php/ajfand/article/view/163672/153148">provide</a> affordable and accessible meals, the lack of regulation <a href="https://www.tandfonline.com/doi/full/10.1080/23311932.2023.2266194">poses</a> significant health risks. </p>
<h2>Why street food can be unsafe</h2>
<p>The primary concern is hygiene and food handling practices. Inadequate <a href="https://onlinelibrary.wiley.com/doi/full/10.2991/efood.k.200619.001">access to clean water</a>, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279176/">inappropriate waste disposal</a>, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0956713514004307">temperature abuse</a> and lack of food safety knowledge are common challenges seen among street food vendors. </p>
<p>These conditions can lead to food-borne illnesses, which can be prevented but continue to be a public health issue. The WHO <a href="https://www.who.int/activities/estimating-the-burden-of-foodborne-diseases#:%7E:text=Each%20year%20worldwide%2C%20unsafe%20food,number%20is%20likely%20an%20underestimation.">estimates</a> that each year, there are more than 600 million cases of foodborne illnesses, resulting in over 420,000 deaths, with the greatest burden of these (more than 30%) occuring in children less than 5 years of age. </p>
<p>In Nigeria, there have been pockets of foodborne disease outbreaks over the years which have claimed lives. The Consumer Advocacy for Food Safety and Nutrition Initiative <a href="https://www.gainhealth.org/sites/default/files/publications/documents/report-of-eatsafe-launch-in-nigeria-with-next-steps.pdf#page=3">estimates</a> that 173 million cases of foodborne illnesses occur in Nigeria, resulting in 33,000 deaths annually.</p>
<p>Generally, street food preparation in Nigeria mirrors traditional approaches to food preparation at home. However, <a href="https://jara.org.in/uploads/archivepdf/8025JARA_Vol_03_June_2021_01.pdf">a study in Asaba</a>, Delta State Nigeria highlights that because of the scale and quantity of foods prepared, more than 50% of food processors do not wash raw foods prior to preparation and another 40% of the food processors do not wash their hands. Neither do they practise personal hygiene during the handling of foods. Similarly, many street food vendors <a href="https://pubmed.ncbi.nlm.nih.gov/25258630/">operate in less than perfect environments for food processing</a>: many street food vendor stands have flies, rodents and open waste bins which are risk factors for the contamination of foods. </p>
<p>The lack of a clean and sanitary environment for food processing <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279176/">has been identified</a> as among the key factors that contribute to the contamination of street foods by microorganisms. </p>
<h2>Checking unsafe practices</h2>
<p>A multifaceted approach to these issues must be adopted. </p>
<ul>
<li><p>Training: First, <a href="https://www.tandfonline.com/doi/full/10.1080/23311932.2023.2266194">basic food safety training for vendors</a> is crucial. This training should cover essential hygiene practices, safe food handling and storage procedures. It can be done through local health departments and community organisations. This recommendation draws on <a href="https://www.food.gov.uk/business-guidance/food-hygiene-for-your-business">established principles</a> of hygiene and safe food handling. Continuous training on food safety has <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0287996">proved</a> effective in promoting food safety.</p></li>
<li><p>Enforcement: The government should <a href="https://www.tandfonline.com/doi/full/10.1080/23311932.2023.2266194">develop and enforce</a> food safety regulations specific to street vendors. This requires a balance between ensuring public health and not stifling the livelihoods of the vendors. Subsidising the cost of necessary equipment like portable sinks or refrigeration units could be a part of this initiative. Supplying vendors with hygienic materials has <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0287996">proved</a> to be valuable for preserving and enhancing food safety in low- and middle-income nations.</p></li>
<li><p>Inspection: Regular inspections should be conducted to ensure compliance with these regulations. These should not be punitive but rather supportive, helping vendors to meet the required standards. A <a href="https://www.food.gov.uk/sites/default/files/media/document/Stage%202%20Process_evaluation%20final%20report.pdf">food hygiene rating scheme</a> should be put in place to identify vendors complying with food safety standards as this could motivate them to improve their sanitary conditions.</p></li>
<li><p>Awareness: Public awareness also plays a vital role. Consumers should be educated about the importance of food safety and how to identify vendors who adhere to hygiene standards. <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-019-7475-9">Consumer awareness</a> can create a demand for safer practices, encouraging vendors to comply with regulations.</p></li>
<li><p>Research and development: Finally, research and collaboration with food scientists and public health experts can lead to innovative solutions that are tailored to the Nigerian context. For instance, exploring low-cost preservation techniques or developing mobile apps for health inspection ratings could revolutionise the way street food is regulated.</p></li>
</ul>
<h2>Regulations will save lives and livelihoods</h2>
<p>Regulating street food in Nigeria is not just about preventing disease; it is about preserving a way of life in a safe and sustainable manner. At the heart of this issue are the vendors and consumers, whose lives and well-being are interconnected with the very essence of street food culture.</p><img src="https://counter.theconversation.com/content/220507/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Helen Onyeaka 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>Street food is popular in Nigeria but safety is not regulated.Helen Onyeaka, Associate Professor, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2209682024-02-08T14:00:57Z2024-02-08T14:00:57ZNigeria’s popular wara cheese has a short shelf life: we’ve found a way to keep it fresh for longer<p>Cheese is a highly nutritious food produced in hundreds of varieties around the world. It’s all made by fermenting milk but the results range widely in flavour, texture and end uses.</p>
<p>The global market value of cheese was about <a href="https://www.statista.com/topics/6586/global-cheese-market/">US$83.4 billion</a> in 2022 and is projected to exceed <a href="https://www.statista.com/topics/6586/global-cheese-market/">US$120 billion</a> in 2028.</p>
<p>In Nigeria, the most popular cheese is wara, a soft product with a mild, sweet taste and milky flavour. Wara is produced by coagulating cow’s milk with an extract of sodom apple (<em>Calotropis procera</em>, or bomubomu) and is traditionally sold in its whey (milk-like liquid), sometimes in a calabash, at room temperature. </p>
<p>Unhygienic conditions during production and sale, and lack of good packaging materials, can result in wara containing harmful <a href="https://www.sciencepub.net/nature/0403/06-0176-uzeh-ns.pdf">microorganisms</a> such as <em>E. coli</em>, <em>Staphylococcus aureus</em> and other bacteria. These can spoil the cheese or make a person ill after eating it.</p>
<p>Wara also has a very <a href="https://www.academia.edu/63932279/EFFECT_OF_PRESERVATIVES_AND_STORAGE_CONDITIONS_ON_MICROORGANISMS_IN_NIGERIAN_UNRIPENED_CHEESE_WARA">short shelf life</a> of about two or three days. This can be prolonged by refrigerating, drying or frying the cheese but these processes usually affect the taste, texture, colour, flavour and other sensory properties. They also discard the whey, which is an essential component of wara.</p>
<p>As Nigerian food scientists, we set out to find a way to preserve wara more effectively in its indigenous form. </p>
<p>We used different amounts of sorbic acid and natural ginger as preservatives, separately and in combination, and compared the microbial load in the wara samples. We <a href="https://www.academia.edu/63932279/EFFECT_OF_PRESERVATIVES_AND_STORAGE_CONDITIONS_ON_MICROORGANISMS_IN_NIGERIAN_UNRIPENED_CHEESE_WARA">found</a> that the best combination was 2.5% ginger with 0.05% sorbic acid, and that refrigeration was better than keeping the cheese at room temperature.</p>
<p>Extending its shelf life and improving its safety could boost demand and sales at all outlets, from informal to supermarkets. It would make a nutritious food more accessible and be good for producers and food processing businesses.</p>
<h2>Our research</h2>
<p>In our experiment we <a href="https://www.academia.edu/63932279/EFFECT_OF_PRESERVATIVES_AND_STORAGE_CONDITIONS_ON_MICROORGANISMS_IN_NIGERIAN_UNRIPENED_CHEESE_WARA">preserved</a> wara with chemical and natural preservatives: sorbic acid and ginger respectively. We kept the wara in whey for three weeks. </p>
<p>Sorbic acid was added to different samples at a concentration of 0.05% and 0.1%, which is below its maximum permissible limit of 0.3% in cheese according to the international <a href="https://dairyconsultant.co.uk/pdf/codex_specification_spreadable_processed_cheese">Codex Alimentarius standard</a>. The ginger (known locally as atalẹ) was prepared by washing and peeling rhizomes, slicing them into thin sheets, drying them in an oven at 50°C, and cooling, milling and sieving the dried product to obtain ginger powder. </p>
<p>Wara was produced by filtering 2 litres of fresh cow’s milk. The milk was divided into four portions (A, B, C and D). Preservatives were added in the following concentrations:</p>
<ul>
<li><p>5% ginger to portion A</p></li>
<li><p>2.5% ginger and 0.05% sorbic acid to portion B</p></li>
<li><p>0.1% sorbic acid to portion C</p></li>
<li><p>no preservatives in portion D.</p></li>
</ul>
<p>Each mixture was boiled and an extract of sodom apple leaves was added while boiling. The curd (the solid which separates from the liquid whey) was moulded into a cone shape. Each curd was transferred into a sterile plastic container, covered in whey and <a href="https://ijt.oauife.edu.ng/index.php/ijt/article/view/152">stored</a> in the refrigerator or at room temperature.</p>
<p>The populations and types of microorganisms associated with the preserved wara were determined every week. Microorganisms are important in fermenting milk and most are beneficial, but could cause spoilage if their growth is not controlled.</p>
<p>We also studied the effect of the preservatives on the sensory attributes such as taste, flavour, colour, appearance and texture of the wara samples. </p>
<h2>The outcome</h2>
<p>Preservation of wara with ginger and/or sorbic acid significantly reduced the population of microorganisms during storage. The use of 0.1% sorbic acid to preserve wara was the most effective in reducing bacterial and fungal count. The control sample without preservatives had the highest population of microorganisms. The addition of 2.5% ginger and 0.05% sorbic acid to wara reduced the microorganisms present and was much more effective than the addition of 5% ginger alone. </p>
<p>The physical examination of the stored wara showed that samples stored inside the refrigerator retained their fresh aroma throughout the period of storage. Those stored on the shelf at room temperature showed a change in aroma after two weeks. The samples without preservatives, stored at room temperature, had an offensive odour after a week. Spoilage of samples stored at room temperature was due to the higher rate of microbial metabolism. </p>
<p>There were no pathogenic (disease-causing) organisms in any of the wara samples throughout storage. </p>
<p>Wara samples stored inside the refrigerator had better quality in terms of microbial load, type of microorganisms, colour, texture and aroma than samples kept on the shelf at room temperature.</p>
<p>Freshly made wara samples without preservatives had the highest score for taste, flavour, colour, texture and overall acceptability. The values were not significantly different from the samples treated with 0.1% sorbic acid. Adding 2.5% ginger and 0.05% sorbic acid reduced the sensory scores of wara compared to the 0.1% sorbic acid sample. </p>
<p>In conclusion, we suggest that Nigerian wara can be produced on a large scale by using 0.1% sorbic acid or a combination of 2.5% ginger extract and 0.05% sorbic acid as a preservative. This will increase the time wara can be stored after production, thereby increasing the ability of the producers to scale up. </p>
<p>Preservation of wara can improve nutrition and create employment.</p><img src="https://counter.theconversation.com/content/220968/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Malomo Adekunbi Adetola works for Obafemi Awolowo University, Ile - Ife, Nigeria. She receives funding from Carnegie and the Dutch Ministry of Foreign Affairs. </span></em></p>Nigeria’s soft cheese, wara, could be made more widely available with new techniques to extend its shelf life.Malomo Adekunbi Adetola, Lecturer in Food Science and Technology, Obafemi Awolowo UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2192932023-12-17T13:41:39Z2023-12-17T13:41:39ZEnsure a safe and delicious holiday feast: How to use a food thermometer to prevent foodborne illness<figure><img src="https://images.theconversation.com/files/565861/original/file-20231214-23-un4rke.jpg?ixlib=rb-1.1.0&rect=646%2C71%2C5209%2C3916&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Different foods have different target temperatures to eliminate pathogens, so use a reliable food safety chart and a digital food thermometer when cooking each dish, and whenever you reheat leftovers.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/ensure-a-safe-and-delicious-holiday-feast-how-to-use-a-food-thermometer-to-prevent-foodborne-illness" width="100%" height="400"></iframe>
<p>Most holiday festivities include preparing and eating food. Addressing uninvited guests (pathogens) that lurk in the background is crucial amid the joy and celebration. </p>
<p>As food safety researchers, we study how to protect people from infections caused by <a href="https://www.canada.ca/content/dam/hc-sc/healthy-canadians/migration/publications/eating-nutrition/foodborne-illness-infographic-maladies-origine-alimentaire-infographie/alt/pub-eng.pdf">foodborne pathogens</a>. While you likely know to wash your hands and keep your raw meats separate from other foods, there’s another essential thing to do to avoid spending your holiday in the bathroom: probe your food. </p>
<p>Each year, <a href="https://www.canada.ca/en/public-health/services/food-borne-illness-canada/yearly-food-borne-illness-estimates-canada.html">four million Canadians get sick from the food they eat</a>. The most common cause is <a href="https://doi.org/10.1089/fpd.2012.1389">norovirus, which causes the most illnesses</a>. Other leading causes include the bacteria Listeria, Salmonella, Campylobacter and Shiga toxin-producing E. coli.</p>
<p>The impact is far-reaching, from mild cases causing discomfort to severe instances requiring <a href="https://doi.org/10.1017/S0950268810001883">hospitalization</a>. Each year, these infections cause millions of missed workdays, resulting in <a href="https://doi.org/10.1016/j.ijfoodmicro.2008.06.007">productivity losses</a> and costs of <a href="https://doi.org/10.4315/0362-028X-69.3.651">about $400 million</a>. </p>
<p>The <a href="https://www.who.int/groups/foodborne-disease-burden-epidemiology-reference-group-(ferg)">World Health Organization</a> is currently determining how much foodborne illness occurs globally each year, including the long-term complications that can occur, like <a href="https://doi.org/10.1371/journal.pmed.1001921">kidney disease and Guillain Barré syndrome</a>.</p>
<h2>Ensuring food is cooked correctly</h2>
<p>Many people may not know that a <a href="https://publications.gc.ca/Collection/A104-17-2003E.pdf">food thermometer</a> is the only way to know your food is cooked correctly. A food thermometer is your holiday feast’s unsung hero, ensuring that poultry, meats and other dishes — including those that are vegetable-based — reach the internal temperatures needed to eliminate harmful pathogens. </p>
<p>Proper food thermometer use not only safeguards against illness but also enhances the overall culinary experience by guaranteeing that your dishes are cooked to perfection.</p>
<p>But when should you <a href="https://blog.foodsafety.ca/how-use-and-calibrate-probe-thermometer">use a thermometer, and how</a>? You should <a href="https://doi.org/10.4315/0362-028X.JFP-18-245">use your food thermometer any time you cook meat</a> or other foods high in protein (like quiche, stir fry and plant-based “meats”), and whenever you <a href="https://www.canada.ca/en/health-canada/services/general-food-safety-tips/food-safety-tips-leftovers.html">reheat leftovers</a>. </p>
<p>Different foods have different target temperatures, so use a <a href="https://www.canada.ca/en/health-canada/services/general-food-safety-tips/safe-internal-cooking-temperatures.html">reliable food safety chart</a> to determine the appropriate temperature for each dish. If you are pressed for time, the safest temperature for most foods (except whole birds) is <a href="https://www.canada.ca/en/health-canada/services/general-food-safety-tips/safe-internal-cooking-temperatures.html">74 C (165 F)</a>. Health Canada recommends <a href="https://www.canada.ca/en/health-canada/services/general-food-safety-tips/safe-internal-cooking-temperatures.html">82 C (180 F) for whole birds</a> like turkey and chicken. </p>
<p>You can even update your old recipes and cookbooks by changing “cook until the juices run clear” (or other instructions that are not very useful!) to “cook until it reaches 74 (or 82) degrees Celsius.”</p>
<h2>Choosing and using a food thermometer</h2>
<figure class="align-center ">
<img alt="Illustration of a variety of food thermometers" src="https://images.theconversation.com/files/565864/original/file-20231214-27-mflv4p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565864/original/file-20231214-27-mflv4p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=225&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565864/original/file-20231214-27-mflv4p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=225&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565864/original/file-20231214-27-mflv4p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=225&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565864/original/file-20231214-27-mflv4p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=283&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565864/original/file-20231214-27-mflv4p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=283&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565864/original/file-20231214-27-mflv4p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=283&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Types of food thermometers include instant-read models for quick checks and oven-safe thermometers that you can leave in items while they’re cooking in the oven.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>If you’re among the <a href="https://doi.org/10.4315/JFP-20-148">one-third of Canadians who don’t own a food thermometer</a>, your first step is <a href="https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/kitchen-thermometers">selecting the right one</a>. </p>
<p>Choose a reliable digital food thermometer designed for the specific type of food you’re preparing. <a href="https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/kitchen-thermometers">There are various types</a>, including instant-read thermometers for quick checks and oven-safe thermometers that you can leave in items while they’re cooking in the oven.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/heres-how-much-your-holiday-dinner-will-cost-this-year-218786">Here's how much your holiday dinner will cost this year</a>
</strong>
</em>
</p>
<hr>
<p>To <a href="https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/kitchen-thermometers">check the temperature</a>, insert the thermometer into the thickest part of the food, avoiding bones and fatty areas. For poultry, the thermometer should be inserted into the innermost part of the thigh and wing and the thickest part of the breast. </p>
<p>Make sure to wait until the temperature readout stops changing, to allow the thermometer sufficient time to provide an accurate reading. Finally, make sure you <a href="https://www.canada.ca/en/health-canada/services/general-food-safety-tips/safe-internal-cooking-temperatures.html#s1">wash the thermometer</a> with warm soapy water after each use. </p>
<h2>Cooked to perfection</h2>
<figure class="align-center ">
<img alt="A roast on a carving board with a meat thermometer in it" src="https://images.theconversation.com/files/565863/original/file-20231214-19-sub7nr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565863/original/file-20231214-19-sub7nr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565863/original/file-20231214-19-sub7nr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565863/original/file-20231214-19-sub7nr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565863/original/file-20231214-19-sub7nr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565863/original/file-20231214-19-sub7nr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565863/original/file-20231214-19-sub7nr.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">If a friend cooks the roast beef to sawdust, giving them a meat thermometer can help them cook food to perfection without worrying about pathogens.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Besides making sure food gets hot enough to kill harmful pathogens, there’s other good news about food thermometer use. Does your best friend overcook the roast beef to sawdust level? Do you have a family member who cooks the taste out of chicken in the name of safety? Using a food thermometer <a href="https://blogs.ifas.ufl.edu/seminoleco/2018/02/02/want-your-food-to-taste-better-use-a-thermometer/">can help ensure a moist and delicious meal</a>, bringing friends and family together. </p>
<p>As food safety researchers, our goal is to make sure that “<a href="https://doi.org/10.1111/josh.12782">all Canadians…know how to use a food thermometer, and that it becomes…as much a part of their life as a toothbrush</a>.” On that note, food thermometers make great gifts!</p>
<h2>Handling leftovers</h2>
<p>In addition to using a food thermometer to check that your leftovers are reheated to 74 C before you eat them, there are other important tips for safely handling leftovers this holiday season. </p>
<p><a href="https://www.canada.ca/en/health-canada/services/seasonal-food-safety/holiday-food-safety.html">Refrigerate them promptly in ways that allow them to cool quickly</a>, such as in shallow containers, loosely covered until they are chilled. Either consume them in the next two to three days, or freeze them right away for later use.</p>
<p>Many people prepare unique dishes for the holidays, travel with food and prepared dishes, and host or attend holiday buffets and potlucks. <a href="https://www.canada.ca/en/health-canada/services/seasonal-food-safety/holiday-food-safety.html">Health Canada has specific tips</a> for ensuring your buffets, baked goods, ciders, eggnog, stuffing and more are safe to eat.</p>
<p>Finally, if you do happen to get sick this holiday season with nausea, vomiting, diarrhea or other digestive troubles, make sure you seek health care as needed. From a food safety perspective, the best option, if you can, is to stay out of the kitchen while you are ill and don’t prepare food for others. </p>
<p><em>This article was co-authored by Ken Diplock. He is a professor and program co-ordinator of the Bachelor of Environmental Public Health program at Conestoga College, and a member of the Canadian Institute of Public Health Inspectors.</em></p><img src="https://counter.theconversation.com/content/219293/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shannon Majowicz has held or currently holds research grants and contracts to study food safety related issues from the Canadian Institutes of Health Research, Bill and Melinda Gates Foundation, World Health Organization, British Columbia Centre for Disease Control Foundation Open Award Program, Public Health Agency of Canada, and the Ontario Ministry of Agriculture, Food, and Rural Affairs' Food Safety Research Fund.</span></em></p>A food thermometer is your holiday feast’s unsung hero, ensuring that poultry, meats and other dishes, including vegetable-based, reach the internal temperatures needed to eliminate harmful pathogens.Shannon Majowicz, Associate Professor, School of Public Health Sciences, University of WaterlooLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2177562023-11-24T17:18:22Z2023-11-24T17:18:22ZChicken doesn’t need to be washed before cooking – here’s why<figure><img src="https://images.theconversation.com/files/561077/original/file-20231122-29-3qy0dy.jpg?ixlib=rb-1.1.0&rect=0%2C8%2C5472%2C3628&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Only cooking can remove the harmful pathogens raw chicken contains.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/top-view-preparing-cutting-fresh-raw-1086759212">nerudol/ Shutterstock</a></span></figcaption></figure><p>Social media isn’t exactly known for being a welcoming place to have a productive discussion or share your opinions. Even the most inoffensive posts can breed noxious comments sections. Take this seemingly harmful post on TikTok, in which a woman shares a step-by-step recipe for spatchcocking chicken. </p>
<p><div data-react-class="TiktokEmbed" data-react-props="{"url":"https://www.tiktok.com/@zoebarrie/video/7256943895165078827"}"></div></p>
<p>While you might expect to find comments asking about the recipe or even sharing tips and advice, instead you find comment after comment of people expressing disbelief that the chef didn’t wash her chicken before cooking it. </p>
<p>But despite the number of comments certain the chef has done the wrong thing, in reality she’s made the right move. Washing chicken isn’t just unnecessary – it can actually increase your risk of foodborne illness.</p>
<h2>Why chicken really shouldn’t be washed</h2>
<p>Traces of feathers, slime or dirt might have necessitated washing chicken half a century ago. But nowadays, poultry is <a href="https://www.usda.gov/media/press-releases/2019/08/20/washing-raw-poultry-our-science-your-choice">pre-washed and ready to cook</a> when you buy it.</p>
<p>Still, some people seem to think you should wash your chicken in order to remove the dangerous microorganisms raw meat contains. While it’s true chicken does contain harmful microorganisms, washing prior to cooking doesn’t remove them. </p>
<p>Chicken in particular naturally carries <a href="https://www.cdc.gov/foodsafety/communication/salmonella-food.html">Salmonella</a> and <a href="https://www.cdc.gov/campylobacter/index.html">Campylobacter</a>. These can cause very severe illness, with infections <a href="https://www.cdc.gov/foodsafety/prevention.html">causing symptoms</a> such as fever, nausea, vomiting, diarrhoea and possibly even septicaemia (blood infection).</p>
<p>Children, elderly people, pregnant women and those with other health conditions or poor immune systems are most at risk of illness from these bacteria. But even in healthy people, Salmonella and Campylobacter infections can lead to <a href="https://www.usda.gov/media/press-releases/2019/08/20/washing-raw-poultry-our-science-your-choice">hospitalisations and death</a>. </p>
<p>Washing chicken prior to cooking does not eliminate all the germs within a chicken. At most, it may only remove the bacteria on the surface. But this practice actually makes the <a href="https://www.usda.gov/media/press-releases/2019/08/20/washing-raw-poultry-our-science-your-choice#:%7E:text=Poultry%20(whole%20or%20ground)%20are,and%20immediately%20wash%20your%20hands.">overall infection risk</a> from raw chicken significantly worse, as it may potentially cause the pathogens washed off the chicken skin to spread throughout your kitchen.</p>
<p>When you put raw chicken under the tap, the bacteria on the skin move into the water stream. This will then be splashed into your sink – and potentially your surrounding counters, cupboards and dish rack. This <a href="https://www.safefood.net/food-safety/raw-poultry">water spray</a> can travel up to 80cm – the length of the average adult arm. This makes cross-contamination pretty likely, especially if these water droplets have landed elsewhere in your kitchen. It may even contaminate other uncooked foods you later place in the same sink. </p>
<p>Even if you rinse the sink with water after washing the chicken, this <a href="https://www.usda.gov/media/press-releases/2019/08/20/washing-raw-poultry-our-science-your-choice">may not be sufficient</a> to remove all the pathogenic bacteria that have become attached. </p>
<p>It’s also worth noting that soaking poultry in a brine of water and vinegar or citrus juice does not make it more hygienic. Research has shown that Salmonella <a href="https://www.sciencedirect.com/science/article/abs/pii/S0956713518303244?via%253Dihub">weren’t killed</a> following soaking chicken in vinegar or citrus juice for more than five minutes. Other research shows that <a href="https://pubmed.ncbi.nlm.nih.gov/20132670/">Campylobacter numbers</a> may be reduced following a marinade in vinegar or lemon juice, but it takes 24 hours of soaking.</p>
<h2>Handling raw chicken safely</h2>
<p>There are many simple steps you should follow when preparing raw poultry to keep safe from foodborne illnesses. </p>
<p>The containers or wrappers that raw poultry comes in are often contaminated with bacteria. Once you’ve opened the package and removed the chicken, place it in a clean plastic bag so the contents don’t drip on your kitchen floor or waste bin when you dispose of it.</p>
<p>Next, place your raw poultry on a clean cutting board so you can prepare it.</p>
<p>Since washing creates an unnecessary risk of cross-contamination, if there’s dirt or slime on the surface of the chicken – or if the chicken is wet – simply wipe it off with a paper towel. Immediately dispose the paper towel to avoid contamination.</p>
<figure class="align-center ">
<img alt="A person uses a spray bottle of kitchen disinfectant and a paper towel to clean a counter." src="https://images.theconversation.com/files/561085/original/file-20231122-21-b3uziz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/561085/original/file-20231122-21-b3uziz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/561085/original/file-20231122-21-b3uziz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/561085/original/file-20231122-21-b3uziz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/561085/original/file-20231122-21-b3uziz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/561085/original/file-20231122-21-b3uziz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/561085/original/file-20231122-21-b3uziz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Be sure to disinfect your work area after you’re finished preparing the chicken.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/hand-holding-spray-bottle-clean-stone-122730847">tab62/ Shutterstock</a></span>
</figcaption>
</figure>
<p>If you accidentally drop any meat debris on the work surfaces during preparation, mop it up with a paper towel, dispose of it, then clean the surface with diluted bleach or an antibacterial spray. Dry the surface with a clean paper towel. Likewise, if any spice containers you’re using to season the chicken touch it before it’s cooked, be sure to wipe these down with an antibacterial spray.</p>
<p>When you’re finished preparing your chicken, immediately wash your hands with soap and warm water. You should wash your hands under warm water for <a href="https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/washing-food-does-it-promote-food#:%7E:text=While%2520washing%2520meat%2520and%2520poultry,further%2520washing%2520is%2520not%2520necessary">at least 20 seconds</a> as this will kill any bacteria on your hands.</p>
<p>Then wash your chopping board and utensils. It’s also a good idea to disinfect the surrounding work area with an antibacterial spray or diluted bleach, which you should then dry with a clean paper towel.</p>
<p>You cannot remove the bacteria from your chicken, or indeed any poultry or meat, by washing it. The only way to kill germs and make the food safe to eat is by cooking it.</p>
<p>Cooking poultry at the correct temperature and for the right amount of time is essential for preventing many foodborne illnesses. While the time and temperature will vary depending on how large your chicken is or the recipe you’re using, your chicken should reach an internal temperature of <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3282150/">about 75°C</a>. This is effective at killing bacterial pathogens, including Salmonella and Campylobacter.</p>
<p>Be sure to use a meat thermometer to check your chicken is safe to eat. Another test is to check the juices from the chicken. If they <a href="https://www.taste.com.au/articles/temperature-cooked-chicken-cook-chicken-safely/3dd0buop">run clear</a> and there’s no trace of blood, the chicken is probably cooked sufficiently.</p>
<p>If you’re served what looks like under-cooked chicken, or indeed any poultry, in a restaurant (you can see blood when you cut into the meat) send the food back to be cooked properly.</p>
<p>The bacteria found on raw poultry is natural even though it’s harmful for humans. But so long as you adequately cook your chicken, it’s still safe to eat.</p><img src="https://counter.theconversation.com/content/217756/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Primrose Freestone 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>Washing chicken may actually increase your risk of cross-contamination.Primrose Freestone, Senior Lecturer in Clinical Microbiology, University of LeicesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2174522023-11-20T19:56:02Z2023-11-20T19:56:02ZThis Thanksgiving − and on any holiday − these steps will help prevent foodborne illness<figure><img src="https://images.theconversation.com/files/559841/original/file-20231116-15-tommvh.jpg?ixlib=rb-1.1.0&rect=0%2C21%2C7205%2C5368&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A delicious – and safe – holiday spread involves careful foreplanning and preparation.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/holiday-turkey-dinner-royalty-free-image/836012728?phrase=thanksgiving+dinner&searchscope=image%2Cfilm&adppopup=true">Lauri Patterson/E+ via Getty Images</a></span></figcaption></figure><p>Thanksgiving is a time for gathering with friends and family around the dinner table. No one wants to cause their family or friends to get sick from a foodborne illness on this holiday or any other occasion. </p>
<p>The Centers for Disease Control and Prevention reports that 1 in 6 Americans, or 48 million people, <a href="https://www.cdc.gov/foodborneburden/2011-foodborne-estimates.html">get sick from a foodborne illness</a> each year. According to the CDC, more than 1 million of these people get sick from <a href="https://www.mayoclinic.org/diseases-conditions/salmonella/symptoms-causes/syc-20355329">salmonella</a>, which is the primary pathogen associated with poultry. </p>
<p>As a <a href="https://news.clemson.edu/our-experts/kimberly-baker/">food safety specialist</a>, I educate food producers, manufacturers and consumers on how to ensure the safety of the food they produce.</p>
<p>This Thanksgiving – and, really, for any gathering – make sure you understand how to prepare your meal to ensure that everyone goes home without a foodborne illness. Understanding the safe food practices to follow at home during preparation, cooking, serving and storing leftovers will keep your holiday meal delicious and safe to eat.</p>
<h2>Pathways to foodborne illness</h2>
<p><a href="https://www.cdc.gov/salmonella/general/index.html">Salmonella is a bacteria</a> that causes a foodborne illness called salmonellosis. Salmonella is also often linked to undercooked poultry and beef, undercooked eggs, raw milk and produce. Symptoms of salmonellosis, which include diarrhea, fever and stomach pain, <a href="https://www.foodsafety.gov/food-poisoning/bacteria-and-viruses">can begin six hours to six days</a> after eating contaminated food. </p>
<p>Food contamination occurs when pathogens, toxins or chemicals make their way into food. <a href="https://www.fda.gov/media/83271/download">Common pathogens</a> that are attributed to foodborne illnesses are salmonella, E. coli, listeria and norovirus. Botulism is a foodborne illness that is caused by a toxin that is produced by a bacterium. A bacterial or viral contaminant can get on the food at any point along the <a href="https://www.cdc.gov/foodsafety/production-chain.html">food production chain</a>, from the field, water, equipment, processing, handling, transportation, storage or preparation.</p>
<p>Every person who grows, handles, transports, stores or prepares food along the food production chain plays a very important role in detecting, eliminating or reducing contamination.</p>
<h2>The perennial wisdom of hand-washing</h2>
<p>Any food preparation and handling should always start with hand-washing. </p>
<p>There are five steps to <a href="https://www.foodsafety.gov/blog/wash-your-hands-health">proper hand-washing</a>: </p>
<ul>
<li>Wash hands with running water. </li>
<li>Apply <a href="https://hgic.clemson.edu/snowman-hands-can-prevent-food-borne-illness/">enough soap to create a complete lather</a>.</li>
<li>Scrub hands, including the top, between fingers, around fingernails and wrists for a minimum of 20 seconds.</li>
<li>Rinse hands under running water.</li>
<li>Dry with a paper towel or air dry. </li>
</ul>
<p>Hands should also be washed any time during food preparation that your hands have touched another food or surface that may have pathogens on it. This includes handling raw meat, poultry, seafood or eggs, as well as touching unwashed produce, blowing your nose, touching your cellphone or petting a cat or dog, to name a few.</p>
<p>A study by the U.S. Department of Agriculture’s Food Safety Inspection Service, which is the branch of the USDA that makes sure meat, poultry and eggs are safe for consumption, observed that <a href="https://www.foodsafety.gov/blog/millions-americans-dirty-hands-are-spreading-dangerous-bacteria">97% of study participants failed to wash their hands</a> during food preparation when they should have. So while hand-washing might seem like a no-brainer, clearly it’s not. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/3PmVJQUCm4E?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">It’s hard to overstate the importance of hand-washing prior to food handling.</span></figcaption>
</figure>
<h2>Rinsing the poultry beforehand is a no-no</h2>
<p>While preparing your meal, there are a few critical food-handling steps to follow to prevent cross contamination, or the transfer of pathogens from one surface to another. </p>
<p>First, keep raw meat, poultry and seafood away from raw or ready-to-eat foods. For example, do not prepare your raw turkey next to where you are preparing a salad, or do not cut produce on a cutting board that had raw meat on it without washing it thoroughly first. </p>
<p>Many people may not realize that it is unsafe to rinse poultry before cooking. The USDA recommends <a href="https://www.usda.gov/media/blog/2016/11/16/wash-or-not-wash">leaving poultry unwashed</a> because it can cause pathogens to easily spread throughout the kitchen from the spray of the water. The only exception is a brined turkey. Brined turkeys are required to be rinsed before cooking, but use extra caution when doing so, and be sure to sanitize all surfaces in and around the sink afterward.</p>
<h2>Having a clean work surface is critical</h2>
<p>Another key step to keeping your Thanksgiving meal safe is to effectively <a href="https://extension.colostate.edu/docs/pubs/foodnut/kitchen-sanitize.pdf">clean and sanitize kitchen surfaces and equipment</a> following instructions on your kitchen cleaner. </p>
<p><a href="https://extension.sdstate.edu/make-your-own-kitchen-cleaning-sanitizer">Chlorine bleach</a> is a commonly used sanitizer that can be used in the kitchen, but there are a few things to know before using it. Chlorine bleach works best when mixed with cool – not hot – water and should be made fresh daily before using. To prepare, mix a teaspoon of bleach with one quart of water, and let the solution cover the surface for one minute before wiping, or allow to air dry. </p>
<h2>Cooking the meat to safe temperatures</h2>
<p>Cooking the <a href="https://theconversation.com/why-is-turkey-the-main-dish-on-thanksgiving-193702">Thanksgiving turkey</a> or ham are two more critical steps in preparing a safe holiday meal. </p>
<p>Before cooking turkey, <a href="https://www.usda.gov/media/blog/2016/11/18/how-safely-thaw-turkey">make sure it is completely thawed</a> in the refrigerator. For large birds, this may require up to one week of thawing time, so plan ahead. </p>
<p>All poultry must be cooked to a minimum of 165 degrees Fahrenheit. <a href="https://hgic.clemson.edu/factsheet/how-to-cook-turkey/">Cooking instructions</a> and cooking temperatures will vary based on the cooking method that you choose. But no matter the cooking method, make sure to take the temperature of the turkey in the thickest portion of the breast meat and innermost part of the thigh, being sure not to touch bone with the thermometer. Poultry must be cooked to 165 F because this is the <a href="https://www.fsis.usda.gov/sites/default/files/media_file/2021-12/Appendix-A.pdf">temperature that is required to kill salmonella</a> instantly. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A woman stands in front of a cooked turkey that's sitting on a kitchen counter as she smiles and demonstrates how to handle poultry." src="https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=350&fit=crop&dpr=1 600w, https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=350&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=350&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=440&fit=crop&dpr=1 754w, https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=440&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/560489/original/file-20231120-27-f8dj5z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=440&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Food safety expert Kimberly Baker discusses the finer points of preparing a Thanksgiving turkey.</span>
<span class="attribution"><span class="source">Clemson University</span></span>
</figcaption>
</figure>
<p>Based on the size of your bird and your cooking method, determine the amount of cooking time it will need well ahead of time. If you are cooking it in the oven with other dishes, consider that some extra roasting time may be needed, as the temperature of the oven decreases and extends cooking time every time the oven door is opened. You want to make sure you have enough time to cook the turkey thoroughly and allow approximately 30 minutes of rest time at room temperature before carving.</p>
<p>If you are <a href="https://hgic.clemson.edu/factsheet/holiday-meats-not-just-turkey/">preparing ham</a>, first determine whether it is fully precooked at the time of purchase or if cooking is required. Even if fully cooked, hams still need to be heated to a minimum of 140 F. Those that require cooking need to be cooked to 145 F. Like turkey, roasting time will be based on the size of the ham – plan ahead so you know when to put it in the oven. A thermometer should be used to measure the temperature of the thickest portion of the ham without touching bone.</p>
<h2>Safe handling and storage should not be an afterthought</h2>
<p>Safe handling of the turkey, ham and other side dishes does not end after they are cooked. </p>
<p>If the food is served buffet style and will be kept out at room temperature for an extended period of time, make sure to have a plan to keep hot food hot, which means above 135 F, and cold foods below 40 F, which is equivalent to the maximum safe temperature of a refrigerator. For example, hot foods can be kept hot in a preheated chafing dish, and cold foods can be served in their serving dish that is nestled in a bowl or tray of ice. If you are unable to keep the food hot or cold during service, then make sure they are put away in the refrigerator within two hours after serving. </p>
<p>Thanksgiving leftovers should be stored in the refrigerator for <a href="https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/leftovers-and-food-safety">no more than three to four days</a>. If you have a lot of leftovers that won’t be eaten within this time frame, consider freezing them for a quick meal at a later date, then thaw and eat them within three to four months for best quality. Remember to label and date leftovers so you know what they are and when they were put in the refrigerator or freezer.</p><img src="https://counter.theconversation.com/content/217452/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kimberly Baker 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>Keeping guests safe involves far more than just careful cooking − hand-washing, keeping work surfaces clean, safe handling and proper storage are also key ingredients.Kimberly Baker, Food Systems and Safety Program Team Director and Assistant Extension Specialist, Clemson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2173052023-11-16T14:46:31Z2023-11-16T14:46:31ZThere are too few toilets in Africa and it’s a public health hazard – how to fix the problem<p>Imagine you are miles from the nearest restroom, and nature’s call is urgent – a situation that might raise a mild panic during a hike or at a music festival. Now, picture that same scenario, not as a one-off inconvenience, but as a daily reality. This is the case for about <a href="https://tropmedhealth.biomedcentral.com/articles/10.1186/s41182-022-00416-5">half a billion</a> people globally. </p>
<p>In African countries, the issue of open defecation often goes unaddressed by society and policymakers despite its negative impact on health, economic development, dignity and the environment. </p>
<p>Led from Queen’s University Belfast, a team of multidisciplinary researchers aimed to evaluate how prevalent the practice is in African countries and which social factors are driving it. We also aimed to establish which communities were in most urgent need of interventions. </p>
<p>We used demographic and health surveys, alongside World Bank data. In a <a href="https://link.springer.com/article/10.1007/s10668-023-03992-6">recent paper</a> we set out our findings. </p>
<p>Our main ones were that in Nigeria, Ethiopia, Niger, the Democratic Republic of Congo, Burkina Faso and Chad, a large number of people engaged in open defecation. </p>
<p>We found that as few as ten countries could account for 247 million Africans defecating in the open by 2030 if critical and emergency actions are not taken.</p>
<p>The biggest driver is lack of access to proper sanitation facilities. The poorest individuals, particularly in rural areas, are more likely to resort to open defecation than people in urban areas. In regions with the most critical need, the poorest are 43 times more likely than the wealthy to resort to open toileting. </p>
<p>We recommend tackling poverty, and intervening in regions and communities that urgently need improved sanitation infrastructure and programmes. West Africa needs special attention since many of its communities are in the critical category.</p>
<h2>A systematic approach</h2>
<p>Sanitation has far-reaching implications for food safety. Contaminated water sources and unsanitary conditions can spread waterborne diseases, which can contaminate food and put millions at risk. Addressing open defecation is a step in ensuring the safety and hygiene of the food chain.</p>
<p>The link between poor sanitation and health is well <a href="https://www.who.int/news-room/fact-sheets/detail/sanitation">documented</a>. But our study casts this relationship in a new, alarming light: the likely role of open defecation in antimicrobial resistance. </p>
<p><a href="https://www.who.int/health-topics/antimicrobial-resistance">Antimicrobial resistance</a> is the ability of microbes, such as bacteria, viruses and fungi, to resist the effects of medications that were once used effectively against them. It is a looming crisis, threatening to make antibiotics ineffective. Common infections could once again become deadly. </p>
<p>Our research suggests a probable link between open defecation and antimicrobial resistance. When people defecate outdoors, resistant bacteria from human waste can contaminate water and food. This <a href="https://doi.org/10.1093/jtm/taad069">often leads</a> to faecal-oral diseases and urinary tract infections.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/gutter-to-gut-how-antimicrobial-resistant-microbes-journey-from-environment-to-humans-189446">Gutter to gut: How antimicrobial-resistant microbes journey from environment to humans</a>
</strong>
</em>
</p>
<hr>
<p>However, there is a need for more research to clarify the relationship, its implications and prevention. A clear recommendation from our research is that data about antimicrobial resistance should be integrated into health surveys.</p>
<p>While the full breadth of the study’s findings is huge, its conclusions are clear: open defecation is a challenge in Africa that requires actions. Our research doesn’t just ring the alarm bell; it provides a blueprint for change, identifying specific regions where the practice is most prevalent and where interventions could have the greatest impact.</p>
<h2>What needs to be done</h2>
<p>Addressing open defecation across a continent as vast and diverse as Africa is no small feat. We made a number of recommendations in the study.</p>
<p><strong>A pragmatic three-tier priority system</strong> </p>
<p>This will categorise regions based on the urgency of need for intervention: critical, high, and medium. Regions marked as critical are those with the highest prevalence of open defecation (more than 80% of the population) and the least access to sanitation facilities. These areas need immediate attention with the deployment of resources and sanitation infrastructure. The high priority regions have some access to sanitation. Here, the strategy is a combination of infrastructure development and community education. For medium priority areas (40%-59%), where some sanitation infrastructure may exist, the focus should be on sustainable practices, behavioural change and maintenance of existing facilities.</p>
<p>The system above is just to cut the high rates and inequalities among communities in a country. There is also a lot to do in communities with an open defecation rate of less than 40%. The goal is to reinforce positive behaviour and ensure facilities are maintained and improved. </p>
<p>Policy support, such as incentives for building private toilets or community sanitation blocks, may also help. This tiered strategy hinges on continuous assessment and reallocation of resources. Interventions should respond to the changing landscape as regions improve or decline. </p>
<p><strong>Support sanitation projects and policies</strong></p>
<p>Advocacy is important to increase awareness and donations to organisations that build toilets and provide sanitation programmes in affected areas. </p>
<p><strong>Educate and spread awareness</strong></p>
<p>Learning about the cultural and socio-economic factors that contribute to this practice must be encouraged and the knowledge shared with others. Campaigns that focus on the importance of sanitation for health and the environment are key.</p>
<p><strong>Encourage sustainable sanitation practices</strong></p>
<p>This includes using toilets properly, not littering, and understanding local challenges. The use of compostable toilets and other sustainable waste management practices where traditional toilets are not feasible must be encouraged.</p>
<p><strong>Foster global partnerships for sanitation</strong></p>
<p>Global partnerships can amplify efforts to end open defecation. Collaborations between governments, NGOs, private sector stakeholders and international organisations must be encouraged. Pooling resources and sharing knowledge can lead to more effective and sustainable solutions.</p><img src="https://counter.theconversation.com/content/217305/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The struggle with open defecation is a silent emergency, undermining the continent’s efforts towards sustainable development goals.Omololu Fagunwa, Research Fellow, Queen's University BelfastHelen Onyeaka, Associate Professor, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2118472023-08-31T13:41:54Z2023-08-31T13:41:54ZA fruit fly has landed in your wine – is it OK to drink?<figure><img src="https://images.theconversation.com/files/544624/original/file-20230824-25-c2ho4q.jpg?ixlib=rb-1.1.0&rect=18%2C0%2C6039%2C4014&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/fruit-fly-swimming-red-wine-wasnt-2283078405">Anne Webber/Shutterstock</a></span></figcaption></figure><p>You pour a chilled glass of your favourite sauvignon blanc and are about to take a sip when a fruit fly lands in it. The fly is clearly dead. But given what you know about where flies hang out, you wonder if it’s safe to drink.</p>
<p>Despite their salubrious sounding name, fruit flies (<em>Drosophila</em> species),
eat food that is decaying. They inhabit rubbish bins, compost heaps or any place where food is present, including drains. Rotting food is rich in germs, any of which a fly can pick up on their body and transfer to where it next lands.</p>
<p>These <a href="https://www.sciencedirect.com/science/article/pii/S0362028X22084745">bacteria</a> include <em>E coli</em>, <em>Listeria</em>, <em>Shigella</em> and <em>Salmonella</em>, any of which can cause a potentially serious infection in even healthy people. The fruit fly, you realise, may have just deposited potentially lethal microbes in your wine, so you toss it in the sink and pour a fresh glass. </p>
<p>However, the scientific evidence suggests you may have just wasted a good glass of wine. Wine has typically between 8% and 14% ethanol and has a pH of around 4 or 5 – a pH below 7 is considered acidic. </p>
<p>Alcohol is well known to be inhibitory to germs and is one reason wine can be stored for so long. <a href="https://pubmed.ncbi.nlm.nih.gov/9754789/">Several</a> <a href="https://www.mdpi.com/2304-8158/9/7/936">laboratory</a> <a href="https://pubmed.ncbi.nlm.nih.gov/20629891/">studies</a> have also shown that the combined effects of wine alcohol and organic acids, such as malic acid, can prevent the growth of <em>E coli</em> and <em>Salmonella</em>.</p>
<figure class="align-center ">
<img alt="E coli bacteria" src="https://images.theconversation.com/files/545266/original/file-20230829-17-jfb8mc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545266/original/file-20230829-17-jfb8mc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545266/original/file-20230829-17-jfb8mc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545266/original/file-20230829-17-jfb8mc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545266/original/file-20230829-17-jfb8mc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545266/original/file-20230829-17-jfb8mc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545266/original/file-20230829-17-jfb8mc.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">Wine is known to inhibit the growth of germs, such as E coli.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/escherichia-coli-bacterium-e-gramnegative-rodshaped-1026248248">Kateryna Kon/Shutterstock</a></span>
</figcaption>
</figure>
<p>Whether the germs transmitted by the fruit fly into the wine can cause an infection <a href="https://www.ift.org/news-and-publications/food-technology-magazine/issues/2021/may/columns/food-safety-and-quality-infectious-doses-of-foodborne-illness">depends on</a> the number of bacteria deposited (the “infectious dose”) and how metabolically fit the germs are. The wine the fruit fly entered was also chilled, which some food poisoning bacteria find <a href="https://www.frontiersin.org/articles/10.3389/fmicb.2016.01151/full">shocks their metabolism so profoundly</a> it stops them growing.</p>
<p>As all types of wine (red, white or rosé, whether chilled or room temperature) are naturally antibacterial, germs in wine are <a href="https://pubmed.ncbi.nlm.nih.gov/20629891/">likely to become damaged</a>, which will reduce their infection fitness. This suggests that while the germs deposited into wine by the flies might be present in a dose high enough to cause illness, they are not likely to cause an infection as they are too damaged. So, in all likelihood, the contaminated wine could be drunk without ill effect – whether it was chilled or not.</p>
<h2>Then it has the body to contend with</h2>
<p>And if not damaged directly by the wine, any germs still alive from the fruit fly deposit will encounter the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7684463/pdf/WJG-26-6706.pdf">highly acidic fluids of the human stomach</a>. </p>
<p>Food poisoning germs are highly sensitive to acid, which damages their DNA, and stomach acid can even kill them. In the stomach, germs must also overcome other deadly barriers such as digestive enzymes, entrapping mucus and the ever-watchful immune system defences. Fly-deposited wine germs are <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7553086/pdf/fmicb-11-556140.pdf">unlikely to be able to set up an infection</a>.</p>
<p>Unless you are germ-phobic, I would suggest removing the fly and drinking the wine. If you want the extra protein, you could even swallow the fly.</p>
<p>The fruit fly is unlikely to change the taste of the wine, even if there are several of them. Your digestive system will simply process the fly like any other protein. Salud!</p><img src="https://counter.theconversation.com/content/211847/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Primrose Freestone does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A microbiologist explains the risks to your health of a fly landing in your chilled glass of sauvignon blanc.Primrose Freestone, Senior Lecturer in Clinical Microbiology, University of LeicesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2118082023-08-22T11:38:58Z2023-08-22T11:38:58ZThe sniff test is not reliable for food safety – here’s why<p>I should know better, but I admit that I do it too. I’ve just pulled some sliced chicken out of the fridge, as I set out to make up some sandwiches. I notice the chicken is within its use-by date, but I’m still suspicious. Another member of the family has unlovingly ripped open the packaging and the slices have been sitting exposed in the fridge for several days. Wondering if the chicken is still usable, I give it a good sniff, hoping for some evidence that it is still good or has gone off.</p>
<p>I should know better because I’m a microbiologist, and I know that the microbes that I might be worried about making me sick have no smell. Yet, there I am, trying and failing to give myself confidence with the old sniff test. </p>
<p>It’s certainly true that some microbes create odours when they are growing. Favourites include the lovely smell of yeast in freshly risen or baked bread, which is in stark contrast to - and please excuse the toilet humour – the aversion we all have to the gaseous concoctions created by our microbes that come in the form of flatulence or bad breath. </p>
<p>These gases arise when microbial populations are growing and becoming abundant – when the metabolism of each microbial resident converts carbon and other elements into sources of energy or building blocks for their own cellular structure. However, the microbes that are most commonly associated with foodborne illness, such as <em>Listeria</em> and <em>Salmonella</em>, are going to be near impossible to pick up with the sniff test.</p>
<p>Even if present – and the <a href="https://www.gov.uk/government/statistics/united-kingdom-food-security-report-2021/united-kingdom-food-security-report-2021-theme-5-food-safety-and-consumer-confidence">risk is thankfully relatively low</a> – these bacteria would probably be at such a small amount in the food that any metabolic action (and then odour production) would be entirely imperceptible to our noses. </p>
<p>Also, any eau de <em>Listeria</em> would be indistinguishable from the minor odours that would be made by the more abundant microbial species that are common and expected to be on our foods, and which cause us no health concerns. </p>
<p>Yes, there’s a very small chance that <em>Listeria</em> may be present in the smoked salmon that I picked up at the coastal smokehouse last week. But absolutely no chance that my olfactory senses can detect any hints of <em>Listeria</em> over the delicious smells of the dill and salts and smoke that make up the product.</p>
<p>Back to my sandwich construction. There’s even less of a chance of smelling any <em>Salmonella</em> on the tomato that I dug out from the fruit and veg drawer in the fridge – even if I had super <em>Salmonella</em>-smelling powers, which I don’t. If this pathogen was ever present on the tomato, it was probably introduced by contaminated water on the farm while the tomato was growing, so it is not on the surface of the tomato but within the tomato and doubly impossible to smell.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/543737/original/file-20230821-17-rcr69k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/543737/original/file-20230821-17-rcr69k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=370&fit=crop&dpr=1 600w, https://images.theconversation.com/files/543737/original/file-20230821-17-rcr69k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=370&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/543737/original/file-20230821-17-rcr69k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=370&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/543737/original/file-20230821-17-rcr69k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=465&fit=crop&dpr=1 754w, https://images.theconversation.com/files/543737/original/file-20230821-17-rcr69k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=465&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/543737/original/file-20230821-17-rcr69k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=465&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">There is zero chance you would smell Salmonella in a tomato.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/sliced-tomato-red-tomatoes-on-wooden-1597625194">Gulsina/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Spoiled food can smell, though</h2>
<p>But it is possible to detect when food is spoiled – another action of microbes, as they eat away at food that has been left for too long or has been in the wrong storage conditions. This is one of the reasons why a more appropriate use of the sniff test is to suss out spoiled <a href="https://my.morrisons.com/blog/community/sniff-test/">milk</a> and help limit food waste, rather than throw out milk that might otherwise be safe. And for some foods – think of the microbial contribution to the finest cheeses – it is a culinary attribute to be malodorous. </p>
<p>While my wife disagrees with the aromatic attributes of some fermented foods, such as kimchi, and has banned them from the house, these are definitely not spoiled and should not be destined for the bin. Instead, for other foods, such as fresh fruits or vegetables or milk, I still pay heed to any odours suggestive of spoilage and take these as a warning to do a better job of storing that particular food type in the future – or to make less or buy less of it if I’m not eating it in time. </p>
<p>I also reflect that some of the <a href="https://www.food.gov.uk/research/foodborne-disease/the-burden-of-foodborne-disease-in-the-uk-2018-0">causes of foodborne illness</a> are still unknown to us. While many cases of illness are known to be caused by bacterial contaminants such as <em>Campylobacter</em> or the other microbes I’ve mentioned, there are just as many cases where we don’t yet know the source. But we’re getting better at this too, with <a href="https://food.blog.gov.uk/2021/11/23/path-safe-tracking-foodborne-pathogens-and-antimicrobial-resistant-microbes/">scientists</a> creating tools much more accurate than our nose at detecting food-borne pathogens. </p>
<p>So, if I’m ever worried about becoming sick from my food, my energies are best spent on storing them at the right temperature and cooking them for the right amount of time, rather than trusting my nose to sniff out a pathogen. I wouldn’t even trust my nose to tell the difference between a cabernet and shiraz, let alone a <em>Campylobacter</em> and <em>Salmonella</em>.</p><img src="https://counter.theconversation.com/content/211808/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Matthew Gilmour receives funding from Biotechnology and Biological Sciences Research Council (BBSRC). He is affiliated with the UK Food Safety Research Network which connects food businesses, food and health policymakers, and academia to collaboratively pursue shared research priorities that will protect the UK from foodborne microbial hazards.. </span></em></p>Some people like to use their sense of smell to tell if food has gone off. A food safety expert explains why that’s not a good idea.Matthew Gilmour, Research Scientist; Director, Food Safety Research Network, Quadram InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2090492023-07-23T10:01:46Z2023-07-23T10:01:46ZFood safety policy neglects informal markets in developing countries - 3 ways this can change<figure><img src="https://images.theconversation.com/files/537827/original/file-20230717-248129-a9slss.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The informal sector poses great challenges for food safety. </span> <span class="attribution"><span class="source">Steven Jaffee</span></span></figcaption></figure><p>The food industry in many low- and middle-income countries is dominated by the informal sector. Numerous micro and small businesses, which are not legally registered and mostly compete on the basis of price, handle much of the food that people eat. This includes meat, fish and fresh fruit and vegetables. Informal businesses also dominate when it comes to out-of-home eating.</p>
<p>Fresh foods are important vectors of food-borne diseases, chemical contaminants and other hazards. But in the informal sector there are widespread deficiencies in food safety awareness and in the way food is stored, prepared and handled. Hygiene is not always good at places where vendors work. Consumers are mainly focused on price and have limited ability to protect themselves from unsafe foods.</p>
<p>The informal sector therefore poses great challenges for food safety. </p>
<p>We recently published a report that looked at food safety risks in the informal sector of developing countries. Our <a href="https://cgspace.cgiar.org/handle/10568/130652">report</a> suggests that food sourced through informal markets accounts for 80% of cases of food-borne disease in low-income countries. In lower middle-income countries, the proportion is 65%. </p>
<p>There has been growing attention on food safety in low- and middle-income countries by governments and international development agencies. Our report shows, however, there’s a big policy blind spot in this area. Most food safety initiatives focus on medium or larger food manufacturers, elements of the so-called “modern retail”, food exports and commercial farms or better organised smallholder producers. Also, most attention is given to upgrading national food safety regulations.</p>
<p>The informal sector is typically given minimal attention. There are exceptions. But most efforts to upgrade the food handling practices of informal food vendors have had only short-lived impacts and are not scalable. The need for traditional food markets to be upgraded and for the capacity of towns and cities to regulate informal food businesses are glaring omissions.</p>
<p>We conclude in our report that tackling the food safety problem in low- and middle-income countries requires a fundamental shift in thinking and practice. Actions towards improving food safety must be implemented by local governments and municipalities where informal markets are based. There must be synergies with other goals and interventions, for example the provision of safe water and improved sanitation. And government agencies need to balance incentives and deterrents better when trying to get informal food businesses to use better food safety practices.</p>
<h2>Informal markets</h2>
<p>The continued dominance of the informal sector in low- and middle-income countries might be considered a transitional issue that will naturally go away with time. That is, food will become safer as economic development proceeds, food systems change, and governments become better at food safety regulation. </p>
<p>Certainly, we have seen supermarkets and other “modern” forms of food distribution emerge in the major cities of these countries. However, food system formalisation takes time. In poorer countries, in particular, informal markets and the traditional operators that work there will continue to dominate for many years. Further, diet and demographic changes in these countries are increasing consumer exposure to food safety hazards, especially as they eat more fresh foods. </p>
<p>On top of this, while significant resources have gone into strengthening national food safety agencies in some countries, the impact on the informal sector has been minimal. Central government agencies typically have little regular contact with the informal sector, and even less influence over it.</p>
<p>The informal sector is often an afterthought when low- and middle-income countries look to upgrade their food safety controls. Worse, it is seen as a legacy of the past, not fitting with the national vision of a modern, competitive and resilient food system. Government officials ignore many informal food businesses. Or worse, they do what they can to make them go away, for example by disrupting their commerce or imposing draconian fines.</p>
<h2>Tailored solutions</h2>
<p>Much of the food safety problem is a natural consequence of the limited capacity and weak incentives of informal food businesses. Sustainable improvements are needed to address both issues simultaneously. </p>
<p>Local circumstances, including market and administrative structures, and the state of physical infrastructure, vary greatly. There are also variations in the risk profile of different types of informal businesses, be they market sellers, micro food processors or street food vendors. A “one size fits all” approach won’t do. Solutions need to be customised to local conditions and to the targeted players.</p>
<p>Three fundamental shifts are needed to achieve greater and more sustained progress towards safer food in low- and middle-income countries.</p>
<p>The epicentre of attention needs to shift from central to local governments. It is municipal governments that interact with informal food businesses and influence the conditions in which they operate. These include access to clean water and sanitation and the physical condition of markets. Municipalities lay down most of the controls on the activities of local food businesses. Central governments need to empower local governments to act, giving them the legal authority and resources they need, and laying down frameworks for local action and for sharing experiences.</p>
<p>The focus should be on multisectoral interventions that could combine food safety with attention to animal health, environmental health, nutrition, safe water and sanitation. Stand-alone food safety projects and programmes may not be the best way to mobilise and use resources in the informal sector.</p>
<p>Regulation of the informal sector by government agencies should be reset. It should aim to enable gradual and sustained improvements in food safety practices. Government officials should mainly provide advice and support services, and be rewarded on the basis of incremental food safety improvements. Regulatory enforcement will still be needed, but should be the last resort.</p><img src="https://counter.theconversation.com/content/209049/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Improving food safety in low- and middle-income countries requires a shift in thinking and practice.Spencer Henson, Professor of Food Economics, University of GuelphSteven Jaffee, Lecturer, University of MarylandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2081442023-07-18T07:34:37Z2023-07-18T07:34:37ZMalnutrition in South Africa: how one community wants resources to be spent<figure><img src="https://images.theconversation.com/files/535329/original/file-20230703-269585-e1naed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Proposed solutions to malnutrition included providing school breakfast. </span> <span class="attribution"><span class="source">Richard van der Spuy/Shutterstock</span></span></figcaption></figure><p>South Africa has persistently high rates of <a href="https://ci.uct.ac.za/sites/default/files/content_migration/health_uct_ac_za/533/files/CG2020_ch1_slow%2520violence%2520of%2520malnutrition.pdf">hunger and malnutrition</a> among mothers and children. More than a quarter – <a href="https://dhsprogram.com/pubs/pdf/FR337/FR337.pdf#page=213">27%</a> – of children under five are stunted and <a href="https://dhsprogram.com/pubs/pdf/FR337/FR337.pdf#page=219">61%</a> of children are iron-deficient. <a href="https://dhsprogram.com/pubs/pdf/FR337/FR337.pdf#page=332">Sixty-nine percent</a> of women of reproductive age are overweight or obese, and 31% are iron-deficient.</p>
<p>These figures paint a worrying picture. They suggest gaps in the country’s <a href="https://dhsprogram.com/pubs/pdf/FR337/FR337.pdf">evidence-based</a> nutrition policies and services. </p>
<p>One way to accelerate progress on malnutrition is through engaging with the people who are directly affected by policies. </p>
<p>South Africa’s health system strategy does include <a href="https://www.health.gov.za/wp-content/uploads/2020/11/depthealthstrategicplanfinal2020-21to2024-25-1.pdf">public consultation</a>. But public participation is mostly limited to public meetings once a policy has already been drafted. This leaves little opportunity for substantial revisions. The lack of meaningful public engagement is also evident in how funds for mother and child nutrition are allocated. <a href="http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0256-95742018000300016">Decisions are left to policy makers</a> and there’s little input from people on the ground. </p>
<p>Only by understanding what communities consider important can policies respond to the actual needs of individuals.</p>
<p>We are a group of social scientists at the University of the Witwatersrand who have been exploring approaches for public engagement. We designed a study that puts communities into the shoes of policy makers. We asked community members which programmes they would prioritise if they were given a limited health budget.</p>
<p>The <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-023-15761-1#ref-CR14">respondents</a> in Soweto, an urban township in South Africa with constrained resources, didn’t focus much on health system programmes. They put more emphasis on the underlying causes of malnutrition. To help mothers and children be well nourished they proposed: providing school breakfast; paid maternity leave; improved food safety; and establishing community gardens and clubs.</p>
<p>This article presents one approach for public engagement. We suggest policy makers, researchers and funders consider programmes that communities view as essential for improving mother-and-child nutrition.</p>
<h2>The study</h2>
<p>To engage communities, we modified an exercise called <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-023-15761-1#ref-CR14">CHAT (Choosing All Together)</a>. CHAT is a simulation exercise, something like a board game. It offers a practical way to involve the public in making healthcare decisions. It seeks to show not only which programmes people prioritise, using a limited budget, but the values (assumptions, beliefs or perspectives) those priorities are based on.</p>
<p>Our research team modified CHAT specifically for the context of Soweto. Members of the community were invited to select a package of programmes they saw as priorities to improve mother-and-child nutrition. Fifty-four adult men and women volunteered to part take in the exercise. As with policy makers in real life, they had to make difficult decisions around what to include in their package of programmes, what to leave out (given a limited budget), and why. The volunteers had to discuss and debate their choices to convince one another why one programme would be better for the community than another.</p>
<p>Participants worked together in small groups and they could select from 14 programmes. Five programmes were “nutrition-specific” (directly influenced the immediate causes of malnutrition) and delivered through the healthcare system (pregnancy supplements). Nine programmes were “nutrition-sensitive” (addressed the underlying causes of nutrition), and accessed in non-health sectors (extended paid maternity leave).</p>
<h2>The outcomes</h2>
<p>Community members’ top three priorities were:</p>
<ul>
<li><p>the provision of school breakfast </p></li>
<li><p>extending paid maternity leave to six months and to those in informal employment </p></li>
<li><p>ensuring that food sold by street vendors and served in schools and creches was prepared in a safe and hygienic way. </p></li>
</ul>
<p>Affordable healthy food, help in finding jobs, and community gardens were other programmes the participants considered important to improve their community’s mother-and-child nutrition.</p>
<blockquote>
<p>I think community gardens can help everyone. To be able to, if you want to, grow vegetables and sell them to people, to be able to get money and teach children and other older people to do gardening.</p>
</blockquote>
<p>The community’s choices reflect the values of fairness, equity, social justice and children’s well-being. Participants showed a willingness to consider other viewpoints and reflect on the consequences of their choices for the entire community. </p>
<p>Programmes that would interrupt the intergenerational cycle of poverty were important. These included freeing up disposable income by growing more of their own food, enhancing their self-reliance overall – which could also uplift the neediest among them – and reducing their dependence on social welfare.</p>
<p>In the South African context of astronomical rates of unemployment (<a href="https://www.statssa.gov.za/?p=15407">more than 60%</a> among young adults), solutions like establishing community gardens represented paths to livelihoods, socio-economic empowerment, and supporting the neediest in the community. </p>
<h2>Translating public engagement into action</h2>
<p>Public engagement is entrenched in the constitution and in various policy documents. But there are gaps. Even where public engagement has occurred it has had very little impact on policy making.</p>
<p>For South Africa to uphold its <a href="https://www.health.gov.za/wp-content/uploads/2020/11/depthealthstrategicplanfinal2020-21to2024-25-1.pdf">commitment</a> to equity in healthcare, engaging the public on ethical and social values should be part of a systematic process of setting priorities in government.</p>
<p>Addressing malnutrition will also require coordinated actions across many sectors. Our findings show that not all potential solutions (such as community gardens and extended maternity leave) would fall to the already overburdened health system. </p>
<p>The <a href="https://www.nutritionsociety.co.za/wp-content/uploads/2021/02/National-Food-and-Nutrition-Security-Plan-2018-2023.pdf">South African National Food and Nutrition Security Plan 2018-2023</a> already has cross-sectoral coordination as an objective, via the establishment of a multisectoral advisory council to oversee alignment of policies, and coordinate and implement programmes. Integrating public engagement, through using tools like CHAT, could complement such efforts.</p><img src="https://counter.theconversation.com/content/208144/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Agnes Erzse receives funding from the SAMRC/Wits Centre for Health Economics and Decision Science, PRICELESS, University of Witwatersrand School of Public Health, Faculty of Health Sciences, Johannesburg South Africa (23108).</span></em></p><p class="fine-print"><em><span>Aviva Tugendhaft receives funding from The SAMRC/Wits Centre for Health Economics and Decision Science, PRICELESS, University of Witwatersrand School of Public Health, Faculty of Health Sciences, Johannesburg South Africa (23108).</span></em></p>Failing to understand what communities consider important greatly diminishes the responsiveness of policies to the actual needs of individuals.Agnes Erzse, Researcher, SAMRC/Centre for Health Economics and Decision Science- PRICELESS SA, University of the WitwatersrandAviva Tugendhaft, Senior Researcher, SA MRC Centre for Health Economics and Decision Science, PRICELESS SA, Faculty of Health Sciences, Wits School of Public Health, University of the WitwatersrandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2046822023-07-13T03:17:27Z2023-07-13T03:17:27ZConsumers want NZ farmers to comply with regulations – better monitoring and transparency would help to build trust<figure><img src="https://images.theconversation.com/files/535673/original/file-20230704-3107-dn8cc2.jpg?ixlib=rb-1.1.0&rect=33%2C207%2C4367%2C2220&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Fiona Goodall/Getty Images</span></span></figcaption></figure><p>Assurance systems such as freshwater monitoring are a cornerstone of New Zealand’s agribusiness. They enable compliance with regulations, product safety and international trade. </p>
<p>But these systems face <a href="https://link.springer.com/article/10.1007/s10551-020-04539-9">growing challenges</a>. Urban communities demand higher transparency and engagement, and consumers are increasingly sceptical of the effectiveness and compliance of farm operations. </p>
<p>Based on a recent survey, we developed a <a href="https://ourlandandwater.nz/outputs/enhancing-farm-assurance-a-white-paper/">white paper</a> to address these challenges and to improve farm assurance systems. We explore technological developments, public awareness and the potential to incorporate Māori perspectives. </p>
<p>The survey was designed to gather public perceptions of farm assurance and identify ways to enhance public understanding of farming and its impacts. </p>
<p>It suggests better farm monitoring systems could strengthen agriculture’s social license to operate. It also highlights the importance of transparency, accountability and engagement with interest groups and communities to foster trust and ensure compliance.</p>
<h2>Public perceptions of farm monitoring</h2>
<p>The survey shows most respondents have positive views of assurance programs in New Zealand. They believe farm monitoring programs are necessary to ensure food safety, animal welfare and sustainable use of water and land.</p>
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<p>However, it also highlights the need for better public engagement with these programs as many respondents were not familiar with how they work.</p>
<p>Based on our survey, most New Zealanders believe on-site farm inspections are essential for efficient farm monitoring. But they also acknowledge the constraints of these inspections. A significant number of respondents suggest the use of technology to supplement them. </p>
<p>Respondents recognise the value of independent governance and personal interaction when monitoring farms. The public values the participation of qualified personnel and on-site visits, while having less confidence in monitoring conducted by commercial partners and, in part, modern technologies. </p>
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<strong>
Read more:
<a href="https://theconversation.com/a-new-farming-proposal-to-reduce-carbon-emissions-involves-a-lot-of-trust-and-a-lot-of-uncertainty-185121">A new farming proposal to reduce carbon emissions involves a lot of trust – and a lot of uncertainty</a>
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<p>The survey also reveals the public considers auditors and inspectors trustworthy if they have industry experience, high integrity and are approved by independent certifying bodies. Respondents value the independence of individuals involved in farm assurance.</p>
<p>These findings suggest organisations and farmers should prioritise transparency and independence when developing or improving farm assurance programs to build public trust and improve their reputation.</p>
<h2>Use of technologies for farm monitoring</h2>
<p>Food safety, animal welfare and water quality are the respondents’ main concerns. Many would like to see Māori values and land practices incorporated into monitoring systems.</p>
<p>The public is interested in sharing information about farm performance through mechanisms such as benchmarking and audit grades. Views differ about data sharing, but it is clear that disclosing more details about farm performance will play a major role in developing a positive relationship with the public. </p>
<p>Survey participants were not fully supportive of futuristic concepts such as 24/7 monitoring of farms through satellites or remote sensors. However, they encouraged the use of technology to improve farm assurance programs.</p>
<figure class="align-center ">
<img alt="A drone flying over a farm." src="https://images.theconversation.com/files/535675/original/file-20230704-17768-4if4y6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/535675/original/file-20230704-17768-4if4y6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/535675/original/file-20230704-17768-4if4y6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/535675/original/file-20230704-17768-4if4y6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/535675/original/file-20230704-17768-4if4y6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/535675/original/file-20230704-17768-4if4y6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/535675/original/file-20230704-17768-4if4y6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">The survey shows support for technology to improve farm monitoring.</span>
<span class="attribution"><span class="source">Shutterstock/Attasit saentep</span></span>
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<p>The survey also shows substantial support for unannounced farms visits. However, we found variation in the level of support for monitoring technologies based on respondents’ level of knowledge about farming. This highlights the importance of education and outreach.</p>
<h2>Incorporating a Māori worldview</h2>
<p>Māori concepts and approaches increasingly guide national policies and regulations, especially for environmental issues. This involves understanding the environment in a relational way and emphasising the interdependence between humans and the land and water they rely on. </p>
<p>Māori farming collectives are investing in <a href="https://ourlandandwater.nz/wp-content/uploads/2021/08/Tauutuutu_WhitePaper_ExecutiveSummary.pdf">environmental sensing technologies to improve their operations</a>. They use voluntary and compulsory assurance systems to improve governance and market access. </p>
<p>Incorporating Māori worldviews into assurance practices requires investing in trust-building relationships with tangata whenua and recognising local context and authority. The use of Māori values and mātauranga Māori in assurance practices offers innovation but requires careful consideration of local differences.</p>
<h2>Where to from here?</h2>
<p>Based on our study, we suggest the development and implementation of a comprehensive farm assurance strategy to lift the performance of primary sector supply chains in New Zealand. </p>
<p>This strategy should be inclusive, involving all stakeholders in its development and implementation. We recommend a multi-stakeholder approach to funding, including partnerships between the government, private sector and community organisations. Additional funds could come from user fees or grants.</p>
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<p>
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<strong>
Read more:
<a href="https://theconversation.com/robot-farmers-could-improve-jobs-and-help-fight-climate-change-if-theyre-developed-responsibly-162718">Robot farmers could improve jobs and help fight climate change – if they're developed responsibly</a>
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<p>Future work should focus on <a href="https://www.sciencedirect.com/science/article/pii/S0959652623004894">integrating assurance and monitoring systems with data platforms</a>. The strategy should define pathways for the assessment and possible inclusion of technologies such as remote sensing, satellite imaging, <a href="https://www.sciencedirect.com/science/article/pii/S0959652620308209">AI and machine learning</a>. It should explore possible incentives to support the uptake of these technologies and issues related to data security and ownership. </p>
<p>One thing is clear. The New Zealand public is more engaged with the farming sector than it used to be. It is important to use this momentum to build trust with communities.</p>
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<p><em>The authors acknowledge the contribution of Jon Manhire from the Agribusiness Group in the preparation of this article.</em></p>
<hr><img src="https://counter.theconversation.com/content/204682/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pavel Castka received funding from Our Land and Water National Science Challange for this project. He has also recieved funding from New Zealand China Food Protection Network for projects on food safety and assurance. Pavel is affiliated with International Organization for Standardization (ISO) at Technical Committee TC176 and cooperates & consults with various organisations on matters related to assurance.</span></em></p><p class="fine-print"><em><span>John Reid is Managing Director of Earth Quotient - a consultancy specialising in environmental sensing. He receives funding from the Biological Heritage National Science Challenge and the Our Land and Water National Science Challenge.</span></em></p><p class="fine-print"><em><span>Corey Ruha and Xiaoli Zhao do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Consumers’ main concerns regarding farm monitoring are food safety, animal welfare and water quality. Many would like to see Māori values and land practices incorporated.Pavel Castka, Professor in Operations Management and Sustainability, University of CanterburyCorey Ruha, Researcher and Project Manager, University of WaikatoJohn Reid, Senior Research Fellow, University of CanterburyXiaoli Zhao, Lecturer in Strategic Management, Lincoln University, New ZealandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2083622023-06-23T12:29:14Z2023-06-23T12:29:14Z3M offers $10.3B settlement over PFAS contamination in water systems – now, how do you destroy a ‘forever chemical’?<figure><img src="https://images.theconversation.com/files/533599/original/file-20230623-15-nsjvg7.jpg?ixlib=rb-1.1.0&rect=2494%2C1498%2C2997%2C2264&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">How long do chemicals really need to last? </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/pipetting-sample-into-multi-well-tray-royalty-free-image/482185539?phrase=chemicals&adppopup=true">Andrew Brookes via Getty Images</a></span></figcaption></figure><p>PFAS chemicals seemed like a good idea at first. As <a href="https://www.aps.org/publications/apsnews/202104/history.cfm">Teflon</a>, they made pots easier to clean starting in the 1940s. They made jackets waterproof and carpets stain-resistant. Food wrappers, firefighting foam, even makeup seemed better with perfluoroalkyl and polyfluoroalkyl substances.</p>
<p>Then tests started detecting <a href="https://static.ewg.org/reports/2020/pfas-epa-timeline/1998_3M-Alerts-EPA.pdf">PFAS in people’s blood</a>.</p>
<p>Today, PFAS are pervasive in soil, dust and drinking water around the world. Studies suggest they’re in <a href="https://doi.org/10.1289/ehp.10598">98% of Americans’ bodies</a>, where they’ve been <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7906952/">associated with health problems</a> including thyroid disease, liver damage and kidney and testicular cancer. There are now <a href="https://www.cdc.gov/niosh/topics/pfas/default.html">over 9,000 types</a> of PFAS. They’re often referred to as “forever chemicals” because the same properties that make them so useful also <a href="https://www.michigan.gov/-/media/Project/Websites/PFAS-Response/Reports/Report-2018-12-07-Science-Advisory-Board.pdf?rev=4a075fe29d794a3a942729557c4e6745">ensure they don’t break down in nature</a>.</p>
<p>Facing lawsuits over PFAS contamination, the industrial giant 3M, which has made PFAS for many uses for decades, <a href="https://www.prnewswire.com/news-releases/3m-resolves-claims-by-public-water-suppliers-supports-drinking-water-solutions-for-vast-majority-of-americans-301858581.html">announced a US$10.3 billion settlement</a> with public water suppliers on June 22, 2023, to help pay for testing and treatment. The company admits no liability in the settlement, which requires court approval. Cleanup could cost <a href="https://news.bloomberglaw.com/environment-and-energy/3m-heads-to-trial-in-existential-143-billion-pfas-litigation">many times that amount</a>.</p>
<p>But how do you capture and destroy a forever chemical?</p>
<p>Biochemist <a href="https://scholar.google.com/citations?user=fbJ7DGMAAAAJ&hl=en">A. Daniel Jones</a> and soil scientist <a href="https://scholar.google.com/citations?user=K5qNMk4AAAAJ&hl=en">Hui Li</a> work on PFAS solutions at the Michigan State University and explained the promising techniques being tested today. </p>
<h2>How do PFAS get from everyday products into water, soil and eventually humans?</h2>
<p>There are two main exposure pathways for PFAS to get into humans – drinking water and food consumption.</p>
<p>PFAS can get into soil through land application of biosolids, that is, sludge from wastewater treatment, and can they leach out from landfills. If contaminated biosolids are <a href="https://www.michigan.gov/mdard/environment/rtf/biosolids/gen/frequently-asked-biosolids-questions">applied to farm fields as fertilizer</a>, PFAS can get into water and into crops and vegetables.</p>
<p>For example, livestock can consume PFAS through the crops they eat and water they drink. There have been <a href="https://www.michigan.gov/mdard/about/media/pressreleases/2022/01/28/grostic-cattle-company-of-livingston-county-beef-sold-directly-to-consumers-may-contain-pfos">cases reported in Michigan</a>, <a href="https://www.washingtonpost.com/nation/2022/04/11/pfas-forever-chemicals-maine-farm/">Maine</a> and <a href="https://nmpoliticalreport.com/2021/12/21/dairy-farmers-facing-pfas-contamination-now-eligible-for-payment-for-their-cattle/">New Mexico</a> of elevated levels of PFAS in beef and in dairy cows. How big the potential risk is to humans is still <a href="https://www.ewg.org/news-insights/news/2022/04/ewg-forever-chemicals-may-taint-nearly-20-million-cropland-acres">largely unknown</a>. </p>
<figure class="align-center ">
<img alt="Two cows look over a wooden hay trough with a barn in the background." src="https://images.theconversation.com/files/479759/original/file-20220817-18153-uivgbk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/479759/original/file-20220817-18153-uivgbk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479759/original/file-20220817-18153-uivgbk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479759/original/file-20220817-18153-uivgbk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479759/original/file-20220817-18153-uivgbk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479759/original/file-20220817-18153-uivgbk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479759/original/file-20220817-18153-uivgbk.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">
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<span class="caption">Cows were found with high levels of PFAS at a farm in Maine.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/cows-with-high-levels-of-pfas-on-a-farm-royalty-free-image/1178310633">Adam Glanzman/Bloomberg via Getty Images</a></span>
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<p>Scientists in our research group at Michigan State University are working on materials added to soil that could prevent plants from taking up PFAS, but it would leave PFAS in the soil.</p>
<p>The problem is that these chemicals are everywhere, and there is <a href="https://www.michigan.gov/-/media/Project/Websites/PFAS-Response/Reports/Report-2018-12-07-Science-Advisory-Board.pdf?rev=4a075fe29d794a3a942729557c4e6745">no natural process</a> in water or soil effective at breaking them down. Many consumer products are loaded with PFAS, including makeup, dental floss, guitar strings and ski wax.</p>
<h2>How are remediation projects removing PFAS contamination now?</h2>
<p>Methods exist for filtering them out of water. The chemicals will stick to activated carbon, for example. But these methods are expensive for large-scale projects, and you still have to get rid of the chemicals.</p>
<p>For example, near a former military base near Sacramento, California, there is a huge activated carbon tank that takes in <a href="https://www.afcec.af.mil/News/Article-Display/Article/2530050/new-water-treatment-systems-address-pfospfoa-issues-at-former-mather-afb/">about 1,500 gallons</a> of contaminated groundwater per minute, filters it and then pumps it underground. That remediation project has cost <a href="https://www.afcec.af.mil/News/Article-Display/Article/2530050/new-water-treatment-systems-address-pfospfoa-issues-at-former-mather-afb/">over $3 million</a>, but it prevents PFAS from moving into drinking water the community uses.</p>
<p>The U.S. Environmental Protection Agency has <a href="https://www.epa.gov/newsreleases/biden-harris-administration-proposes-first-ever-national-standard-protect-communities">proposed establishing legally enforceable regulations</a> for maximum levels of six PFAS chemicals in public drinking water systems. Two of these chemicals, PFOA and PFOS, would be recognized as individual hazardous chemicals, with regulatory actions enforced when levels of either exceed 4 parts per trillion, which is substantially lower than previous guidance. </p>
<p>Filtering is just one step. Once PFAS is captured, then you have to dispose of PFAS-loaded activated carbons, and PFAS still moves around. If you bury contaminated materials in a landfill or elsewhere, PFAS will eventually leach out. That’s why finding ways to destroy it is essential.</p>
<h2>What are the most promising methods scientists have found for breaking down PFAS?</h2>
<p>The most common method of destroying PFAS is incineration, but most PFAS are remarkably resistant to being burned. That’s why they’re in firefighting foams.</p>
<p><a href="https://www.niehs.nih.gov/health/topics/agents/pfc/index.cfm">PFAS have multiple</a> fluorine atoms attached to a carbon atom, and the bond between carbon and fluorine is one of the strongest. Normally to burn something, you have to break the bond, but fluorine resists breaking off from carbon. Most PFAS will break down completely at incineration temperatures around <a href="https://www.regulations.gov/document/EPA-HQ-OLEM-2020-0527-0002">1,500 degrees Celsius</a> (2,730 degrees Fahrenheit), but it’s energy intensive and suitable incinerators are scarce.</p>
<p>There are several other experimental techniques that are promising but haven’t been scaled up to treat large amounts of the chemicals.</p>
<figure class="align-center ">
<img alt="Several pallets of bottled water sit while people prepare to put it into the trunks of SUVs picking it up." src="https://images.theconversation.com/files/533598/original/file-20230623-29-zc7t2v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533598/original/file-20230623-29-zc7t2v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533598/original/file-20230623-29-zc7t2v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533598/original/file-20230623-29-zc7t2v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533598/original/file-20230623-29-zc7t2v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533598/original/file-20230623-29-zc7t2v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533598/original/file-20230623-29-zc7t2v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Wayland, Mass., one of the cities that sued 3M, distributed bottled water to residents in May 2021 after elevated levels of PFAS were detected in its public water sources.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/because-of-the-elevated-levels-of-pfas-found-in-its-public-news-photo/1233087323?adppopup=true">Pat Greenhouse/The Boston Globe via Getty Images</a></span>
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<p>A group at Battelle has developed <a href="https://doi.org/10.1061/(ASCE)EE.1943-7870.0001957">supercritical water oxidation</a> to destroy PFAS. High temperatures and pressures change the state of water, accelerating chemistry in a way that can destroy hazardous substances. However, scaling up remains a challenge. </p>
<p>Others are <a href="https://doi.org/10.1016/j.jhazmat.2020.124452">working with</a> <a href="https://www.af.mil/News/Article-Display/Article/2009997/air-force-tests-plasma-reactor-to-degrade-destroy-synthetic-chemical-compounds/">plasma reactors,</a> which use water, electricity and argon gas to break down PFAS. They’re fast, but also not easy to scale up. </p>
<h2>What are we likely to see in the future?</h2>
<p>A lot will depend on what we learn about where humans’ PFAS exposure is primarily coming from.</p>
<p>If the exposure is mostly from drinking water, there are more methods with potential. It’s possible it could eventually be destroyed at the household level with electro-chemical methods, but there are also potential risks that remain to be understood, such as converting common substances such as chloride into more toxic byproducts.</p>
<p>The big challenge of remediation is making sure we don’t make the problem worse by releasing other gases or creating harmful chemicals. Humans have a long history of trying to solve problems and making things worse. Refrigerators are a great example. Freon, a chlorofluorocarbon, was the solution to replace toxic and flammable ammonia in refrigerators, but then <a href="https://www.pca.state.mn.us/air/chlorofluorocarbons-cfcs-and-hydrofluorocarbons-hfcs">it caused stratospheric ozone depletion</a>. It was replaced with hydrofluorocarbons, which now <a href="https://www.ccacoalition.org/fr/slcps/hydrofluorocarbons-hfcs">contribute to climate change</a>. </p>
<p>If there’s a lesson to be learned, it’s that we need to think through the full life cycle of products. How long do we really need chemicals to last?</p>
<p><em>This is an updated version of an article originally <a href="https://theconversation.com/how-to-destroy-a-forever-chemical-scientists-are-discovering-ways-to-eliminate-pfas-but-this-growing-global-health-problem-isnt-going-away-soon-188965">published Aug. 18, 2022</a>.</em></p><img src="https://counter.theconversation.com/content/208362/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>A. Daniel Jones receives funding from the National Science Foundation, National Institutes of Health, U.S. Department of Agriculture-National Institute of Food and Agriculture, U.S. Forest Service, and the U.S. Department of Defense Strategic Environmental Research and Development Program (SERDP).</span></em></p><p class="fine-print"><em><span>Hui Li receives funding from the Environmental Protection Agency, U.S. Department of Agriculture, and National Institute of Environmental Health Sciences.</span></em></p>PFAS can be filtered, but getting rid of the chemicals is a monumental challenge. A biochemist and soil scientist explain.A. Daniel Jones, Professor of Biochemistry, Michigan State UniversityHui Li, Professor of Environmental and Soil Chemistry, Michigan State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2061242023-06-04T07:46:48Z2023-06-04T07:46:48ZYour snacks may be delicious, but are they safe?<figure><img src="https://images.theconversation.com/files/528790/original/file-20230529-15-wmgf5g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Roasted meat on sticks popularly known as 'Suya' is a common delicacy in Nigeria. </span> <span class="attribution"><span class="source">Pius Utomi Ekpei/AFP via Getty Images</span></span></figcaption></figure><p>Food safety is a concern for Nigerians after <a href="https://guardian.ng/features/600m-people-suffer-from-foodborne-sicknesses-yearly/">increasing reports of food-borne illnesses</a> in recent years. According to the Consumer Advocacy for Food Safety and Nutrition Initiative (CAFSANI), consumption of unsafe food in Nigeria results in about <a href="https://pdf.usaid.gov/pdf_docs/PA00XX8H.pdf#page=3">173 million cases of diarrhoea</a> and approximately 33,000 deaths due to foodborne illnesses. </p>
<p>The country has over the years experienced repeated outbreaks of diseases that can be transmitted through contaminated food, including <a href="https://ncdc.gov.ng/diseases/info/C">cholera</a> and <a href="https://ncdc.gov.ng/diseases/info/L">lassa fever</a>. </p>
<p>Food safety is a global issue affecting everyone, regardless of location or social status. According to the <a href="https://www.who.int/news-room/fact-sheets/detail/food-safety">World Health Organization</a>, food-borne diseases affect an estimated 600 million people annually, resulting in 420,000 deaths globally.<br>
Nigeria has significant challenges <a href="https://www.mdpi.com/2304-8158/10/8/1878#B17-foods-10-01878">when it comes to food safety</a> – behaviour around food hygiene. For most developing countries, it can be difficult to practise food safety when clean water and sanitation aren’t available. Some of the other factors that influence food safety in Nigeria are population growth, income inequality, long food supply chains, education gaps and poor regulation.<br>
As a <a href="https://sciprofiles.com/profile/951517">microbiological expert</a>, I am often asked, “how safe is my snack?” The answer to this is not straightforward. It depends on various factors like where the ingredients come from, and how snacks are prepared and stored. </p>
<p>In Nigeria, snacks are small food items that are eaten between meals – a quick bite, as a stand-alone treat or with a beverage. They may be savoury or sweet. Examples include chin-chin, meat pie, <a href="https://theconversation.com/you-love-amagwinya-puff-puff-bofrot-heres-a-healthier-version-of-africas-favourite-snack-170845">puff-puff</a> (deep fried dough), sausage rolls (gala), suya (grilled meat), akara (bean cake), kilishi (dried beef jerky), roasted corn, plantain and groundnuts. </p>
<p>These are usually available from street vendors, in local markets and from supermarkets. Supermarket snacks usually come pre-packaged from the factories while snacks purchased from street vendors and open markets are packaged in a variety of materials such as newspapers for suya and kilishi, polyethylene bags for chin-chin and puff-puff and reused plastic bottles for groundnuts. This unconventional packaging may increase the risk of <a href="https://doi.org/10.18034/ra.v5i3.315">contamination with microorganisms</a>.</p>
<p>There are simple and effective ways to make snacks safer for everyone. Choosing ingredients from trusted sources and following proper food preparation and storage methods can make a big difference. </p>
<figure class="align-center ">
<img alt="men standing behind piles of fruits and vegetables arranged on tables" src="https://images.theconversation.com/files/528410/original/file-20230525-25-7fvjqu.jpg?ixlib=rb-1.1.0&rect=14%2C22%2C4905%2C3201&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528410/original/file-20230525-25-7fvjqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528410/original/file-20230525-25-7fvjqu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528410/original/file-20230525-25-7fvjqu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528410/original/file-20230525-25-7fvjqu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528410/original/file-20230525-25-7fvjqu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528410/original/file-20230525-25-7fvjqu.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">
<figcaption>
<span class="caption">Raw fruits and vegetables can be contaminated at the point of sale. Photo by:Pius Utomi Ekpei/AFP.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/roadside-vendors-display-fruits-for-sale-in-lagos-nigerias-news-photo/1239230464?adppopup=true">from www,gettyimages.com</a></span>
</figcaption>
</figure>
<p>By following the tips I offer here, you can enjoy your snacks and reduce the risk of foodborne diseases. Remember, “an ounce of prevention is worth a pound of cure”.</p>
<h2>Managing the risks</h2>
<p><strong>The source of ingredients:</strong> One of the main things that affect the safety of your snack is where its ingredients come from. Raw materials, including fruits, vegetables and animal products, can be <a href="https://www.sciencedirect.com/science/article/pii/S0740002017310158?via%3Dihub">contaminated with harmful microorganisms</a>, such as bacteria, viruses, and parasites. </p>
<p>These microorganisms can cause food-borne illnesses if they are not properly handled and cooked.</p>
<p>To reduce the risk of contamination, it is important to buy <a href="https://www.betterhealth.vic.gov.au/health/healthyliving/food-safety-when-shopping">ingredients from trusted suppliers</a> who have good hygiene practices. </p>
<p>When buying fresh produce, look for signs of spoilage, such as mould, discolouration and foul odours. Avoid buying pre-cut fruits and vegetables, as they are more susceptible to contamination. Always wash fruits and vegetables thoroughly with clean running water before using them.</p>
<p>There are also things to watch out for when buying processed food. Food processing, such as canning and freezing, can kill harmful microorganisms and <a href="https://www.betterhealth.vic.gov.au/health/healthyliving/food-processing-and-nutrition">extend the shelf life of products</a>. But poor processing and handling can lead to contamination and spoilage. </p>
<p><strong>Safe handling and storage:</strong> It’s important to follow <a href="https://www.cdc.gov/handwashing/handwashing-kitchen.html">good hygiene practices</a>, such as washing your hands thoroughly with soap and water before handling food and using clean utensils and equipment. To avoid <a href="https://www.food.gov.uk/safety-hygiene/avoiding-cross-contamination">cross-contamination</a>, separate raw and cooked foods and use different cutting boards for different types of food. Cook food to the <a href="https://www.healthline.com/health/what-temperature-kills-bacteria">appropriate temperature</a> to kill any harmful microorganisms present.</p>
<p>Proper storage can prevent the growth of harmful microorganisms and extend the shelf life of products. <a href="https://opentextbc.ca/foodsafety/chapter/storage-temperatures-and-procedures/">Store perishable items</a>, such as meats, dairy products and cooked foods, in the refrigerator at temperatures of 40°F (4°C) or below. </p>
<p><a href="https://countrylifefoods.com/blogs/country-life-feed/a-quick-guide-on-how-to-store-dried-beans-nuts-and-other-pantry-items">Keep dry foods</a>, such as crackers, cookies and chips, in a cool, dry place away from moisture and heat.</p>
<p><strong>Packaging and labelling:</strong> The <a href="https://www.nafdac.gov.ng/wp-content/uploads/Files/Resources/Guidelines/FOOD/Guidelines%20For%20Food%20Labelling_Labelling.pdf">packaging and labelling</a> of snacks provide important and valuable information about their safety. Look out for products with clear, easy-to-read labels that include information about the <a href="https://www.inecta.com/blog/food-labeling-requirements-what-you-should-know">ingredients, nutritional content and allergens</a>. </p>
<p>Products with damaged or bulging packaging should be avoided as this could be a sign of contamination or spoilage.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/nigerias-street-food-adds-to-the-plastic-problem-green-leaves-offer-a-solution-203618">Nigeria’s street food adds to the plastic problem – green leaves offer a solution</a>
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<h2>Symptoms of food-borne diseases</h2>
<p>Knowing the <a href="http://www.aimspress.com/article/10.3934/microbiol.2017.3.529">most common types of foodborne illnesses</a> and their symptoms is very important. The most common microorganisms that cause food-borne illnesses include salmonella, E. coli, listeria and norovirus. </p>
<p>Symptoms of food-borne illness can range from mild, such as nausea and diarrhoea, to severe, such as kidney failure and paralysis – the inability to move some or all parts of your body.</p>
<p>If you experience or observe any symptoms of food-borne illness after eating a snack, seek medical attention immediately. Food-borne infections can spread quickly, and it is important to take preventive measures to avoid the spread. <a href="https://www.cdc.gov/handwashing/when-how-handwashing.html">Wash your hands</a> frequently and avoid food preparation or handling until you fully recover.</p>
<p>In conclusion, ensuring the safety of your snack requires careful consideration of various factors that can affect its quality and safety. These include the source of ingredients, processing and preparation methods, storage, packaging, labelling, and awareness of common food-borne illnesses.</p><img src="https://counter.theconversation.com/content/206124/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Helen Onyeaka 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>Food safety means checking the source and paying attention to hygiene and storage.Helen Onyeaka, Associate Professor, University of BirminghamLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2050872023-05-16T14:41:27Z2023-05-16T14:41:27ZHow does food get contaminated? The unsafe habits that kill more than 400,000 people a year<figure><img src="https://images.theconversation.com/files/526039/original/file-20230514-182951-p8iehb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Food-borne illnesses usually present as diarrhoea, vomiting and stomach pains. </span> <span class="attribution"><span class="source">Getty Images</span></span></figcaption></figure><p><em>Unsafe foods, according to the <a href="https://www.who.int/news/item/07-03-2022-world-food-safety-day-2022-theme-highlights-the-role-that-safe-nutritional-food-plays-in-ensuring-human-health">World Health Organization</a> (WHO), contribute to poor health, including impaired growth and development, micro-nutrient deficiencies, noncommunicable and infectious diseases, and mental illness. Globally, one in ten people are affected by food-borne diseases each year. Antonina Mutoro, a nutrition researcher at the African Population and Health Research Center, explains what causes food contamination and how we can lower the risk of disease.</em></p>
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<iframe id="noa-web-audio-player" style="border: none" src="https://embed-player.newsoveraudio.com/v4?key=x84olp&id=https://theconversation.com/how-does-food-get-contaminated-the-unsafe-habits-that-kill-more-than-400-000-people-a-year-205087&bgColor=F5F5F5&color=D8352A&playColor=D8352A" width="100%" height="110px"></iframe>
<h2>What is food contamination?</h2>
<p>Access to safe and nutritious food is a basic human right which many do not enjoy, partly because of food contamination. This is defined as the presence of harmful chemicals and microorganisms in food that can cause illness. According to the WHO, food contamination affects about <a href="https://www.who.int/news-room/fact-sheets/detail/food-safety">one in every ten people</a> globally and causes about <a href="https://www.who.int/news-room/fact-sheets/detail/food-safety">420,000 deaths annually</a>. </p>
<p>Food contamination can be:</p>
<ul>
<li><p><strong>physical:</strong> foreign objects in food can potentially cause injury or carry disease-causing microorganisms. Pieces of metal, glass and stones can be choking hazards, or cause cuts or damage to teeth. Hair is another physical contaminant.</p></li>
<li><p><strong>biological:</strong> living organisms in food, including microorganisms (bacteria, viruses and protozoa), pests (weevils, cockroaches and rats) or parasites (worms), can cause disease. </p></li>
<li><p><strong>chemical:</strong> substances like soap residue, pesticide residue and toxins produced by microorganisms such as <a href="https://theconversation.com/what-must-be-done-to-get-toxin-out-of-kenyas-food-supply-127137">aflatoxins</a> can lead to poisoning.</p></li>
</ul>
<h2>What are the most common causes of food contamination?</h2>
<p>The most common cause of food contamination is poor food handling. This includes not washing your hands at the appropriate time – before eating and preparing food, after using the toilet, or after blowing your nose, coughing or sneezing. Using dirty utensils, not washing fruits and vegetables with clean water, and storing raw and cooked food in the same place can also be harmful. Sick people should not handle food. And you should avoid consuming under-cooked foods, particularly meat.</p>
<p>Poor <a href="https://theconversation.com/vegetable-farmers-in-urban-ghana-dont-worry-much-about-food-safety-but-they-should-143706">farming practices</a> can also contaminate food. This includes the heavy use of pesticides and <a href="https://theconversation.com/chickens-from-live-poultry-markets-in-nigeria-could-be-bad-for-your-health-scientists-explain-why-192646">antibiotics</a>, or growing fruits and vegetables using contaminated soil and water. The use of inadequately composted or raw animal manure or sewage is also harmful. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/power-cuts-and-food-safety-how-to-avoid-illness-during-loadshedding-200586">Power cuts and food safety: how to avoid illness during loadshedding </a>
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</em>
</p>
<hr>
<p>Fresh foods can lead to a number of illnesses. In Kenya, for instance, the <a href="https://bmcresnotes.biomedcentral.com/articles/10.1186/1756-0500-7-627">contamination of meat</a>, <a href="https://www.researchgate.net/publication/329170819_Consumer_Risk_Exposure_to_Chemical_and_Microbial_Hazards_Through_Consumption_of_Fruits_and_Vegetables_in_Kenya">fruits</a> and <a href="https://pubmed.ncbi.nlm.nih.gov/24968591/">vegetables</a> with human waste is relatively common. This is attributed to the use of contaminated water to wash food. Flies carrying contaminants can also directly transfer faecal matter and bacteria onto plant leaves or fruits.</p>
<p><a href="https://theconversation.com/informal-food-markets-what-it-takes-to-make-them-safer-161601">Street foods</a> are another common source of food contamination. These foods are widely consumed in low- and middle-income countries because they’re cheap and easily accessible. </p>
<h2>What are the signs that you’ve eaten contaminated food?</h2>
<p>Biological and chemical substances are the most common food contaminants. They account for <a href="https://www.who.int/news-room/fact-sheets/detail/food-safety">more than 200 food-borne illnesses</a>, including <a href="https://theconversation.com/explainer-causes-symptoms-and-cures-of-typhoid-fever-53645">typhoid</a>, <a href="https://theconversation.com/explainer-why-cholera-remains-a-public-health-threat-74444">cholera</a> and <a href="https://theconversation.com/what-led-to-worlds-worst-listeriosis-outbreak-in-south-africa-92947">listeriosis</a>. Food-borne illnesses usually present as diarrhoea, vomiting and stomach pains.</p>
<p>In severe cases, food-borne illnesses can lead to neurological disorders, organ failure and even death. It’s therefore advisable to seek immediate medical attention if you begin to experience symptoms like persistent diarrhoea and vomiting after eating or drinking.</p>
<p>Children aged under five are the most vulnerable to food-borne illnesses. They bear <a href="https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001923">40%</a> of the food-borne disease burden. A child’s immune system is still developing and can’t fight off infections as effectively as an adult’s. </p>
<p>In low- and middle-income countries, reduced immunity in children can also occur as a result of malnutrition and frequent exposure to infections due to poor hygiene and sanitation, including a lack of access to safe water and toilets. Additionally, when children are ill, they tend to have poor appetites. This translates to reduced food intake. Coupled with increased nutrient losses through diarrhoea and vomiting, this can lead to a cycle of infection and malnutrition and, in extreme cases, death. </p>
<p>Pregnant women and people with <a href="https://theconversation.com/how-do-i-improve-my-immunity-expert-shares-tips-on-what-to-do-and-what-to-avoid-198537">reduced immunity</a> due to illness or age are equally vulnerable and extra care should, therefore, be taken to prevent food-borne illnesses among these groups.</p>
<h2>What can we do to prevent food contamination?</h2>
<p>Food-borne illnesses also have negative economic impacts, especially in low- and middle-income countries. The World Bank estimates it costs more than <a href="https://www.worldbank.org/en/news/press-release/2018/10/23/food-borne-illnesses-cost-us-110-billion-per-year-in-low-and-middle-income-countries#:%7E:text=The%20total%20productivity%20loss%20associated,estimated%20at%20US%24%2015%20billion.">US$15 billion</a> annually to treat these illnesses in these countries. So it’s important to have preventive strategies in place.</p>
<p>Food contamination can be prevented through simple measures:</p>
<ul>
<li><p>washing your hands at key times (before preparing, serving or eating meals; before feeding children, after using the toilet or after disposing of faeces) </p></li>
<li><p>wearing clean, protective clothing during food preparation </p></li>
<li><p>storing food properly</p></li>
<li><p>washing raw foods with clean water</p></li>
<li><p>keeping raw and cooked foods separate</p></li>
<li><p>using separate utensils for meats and for food meant to be eaten raw. </p></li>
</ul>
<p>Good farming practices, such as the use of clean water and application of approved pesticides in recommended amounts, can help prevent food contamination. </p>
<p>Food vendors also need to be trained on food safety, and provided with clean water and proper sanitation. </p>
<p>As part of the research team at the African Population and Health Research Center, I’m working on the <a href="https://healthyfoodafrica.eu/blog/promoting-access-to-nutritious-food-in-nairobi-urban-poor-settings/">Healthy Food Africa project</a>, which aims to boost food security in urban informal settlements through the promotion of food safety. In Kenya, the project is working closely with the Nairobi county government to develop a food safety training manual targeting street food vendors. This will go a long way towards improving food safety in the city.</p><img src="https://counter.theconversation.com/content/205087/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Antonina Mutoro 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>Biological and chemical substances are the most common food contaminants and account for over 200 food-borne illnesses.Antonina Mutoro, Postdoctoral Research Scientist, African Population and Health Research CenterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2030582023-05-02T03:43:47Z2023-05-02T03:43:47ZHere’s why your freezer smells so bad – and what you can do about it<figure><img src="https://images.theconversation.com/files/523344/original/file-20230427-28-gy0qd6.jpg?ixlib=rb-1.1.0&rect=206%2C35%2C2568%2C1742&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">TY Lim/Shutterstock</span></span></figcaption></figure><p>Most people would expect a freezer can keep perishable food fresh and safe from spoilage for many months. Unfortunately, this is not always the case.</p>
<p>Have you ever noticed a funky smell in your freezer? Where does it come from and what can be done to fix the problem?</p>
<h2>Hardy microbes and pungent chemicals</h2>
<p>There are several causes for bad smells coming from your freezer. Typically, the culprits are microbes – bacteria, yeasts and moulds.</p>
<p>Although a freezer dramatically slows down the growth of most common spoilage microbes, some can still thrive if the temperature rises above -18°C (<a href="https://www.foodsafety.asn.au/topic/fridge-freezer-foodsafety/">the recommended freezer temperature</a>). This can happen if there is a power outage for more than a few hours, or if you put something hot straight in the freezer.</p>
<p>Food spills and open containers provide an opportunity for microbes to get to work. It’s also worth noting that many microbes will <a href="https://www.safefood.qld.gov.au/newsroom/food-safety-myths-continued/?keyword=freezing">survive freezing</a> and start growing again once conditions are favourable – for example, if you remove the food, partially thaw it, and return it to the freezer.</p>
<p>Two things happen when food breaks down. First, as microbes start to grow, several pungent chemicals are produced. Second, the fats and flavours that are part of the food itself can and will be released.</p>
<p>These are generally referred to as volatile organic compounds (VOCs). They are the pleasant aromas that we sense when we eat, but VOCs can also be produced by bacteria.</p>
<p>For example, many of us would be familiar with the smells that come from fermentation – a microbial process. When fermenting a food, we intentionally contaminate it with microbes of known characteristics, or provide conditions that favour the growth of desirable microbes and subsequent production of aromatic compounds.</p>
<p>By contrast, uncontrolled food spoilage is problematic, especially when the contaminating microbes can cause disease.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of chopsticks picking up a piece of kimchi from a white bowl" src="https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/523356/original/file-20230428-28-iqy59g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Kimchi is one of the foods we deliberately allow to be ‘contaminated’ in order to produce the intense flavour.</span>
<span class="attribution"><span class="source">Nungning20/Shutterstock</span></span>
</figcaption>
</figure>
<h2>Freezing changes the food</h2>
<p>It is not only microbial growth that can lead to undesirable odours. There’s a suite of chemical processes happening in the freezer, too.</p>
<p>Freezing causes physical changes to foods, often enhancing their breakdown. Many of us would be familiar with “freezer burn” on meats and other foods, as well as ice crystals on frozen food.</p>
<p>This phenomenon is called “<a href="https://en.wikipedia.org/wiki/Brine_rejection">salt rejection</a>”. Depending on how rapidly something is frozen, salts can sometimes be concentrated, as pure water freezes at a higher temperature than water with things dissolved in it – like sugars and salts. On a large scale, this happens to icebergs in the ocean. As the sea water freezes, salt is removed. Thus, the iceberg is composed of fresh water, and the surrounding sea water becomes a saltier and denser brine.</p>
<p>In a similar way, as water in food freezes, organic molecules are concentrated and expelled. If these are volatile, they move about the freezer and stick to other things. Where they end up depends on what else is around.</p>
<p>Some of the volatiles like water. We call them “hydrophilic” or water loving; those are the ones that will make your food taste bad. Other are more water-hating or “hydrophobic” and they stick to things like silicone ice cube trays, <a href="https://www.nytimes.com/wirecutter/blog/how-to-get-smells-out-of-silicone-kitchenware/">making them go smelly</a>.</p>
<p>Domestic freezers are commonly attached to a refrigerator, and this provides another opportunity for smells to move through the systems. The two units share a single cooling source and airflow channel. If your fridge has foul odours from the food inside (natural or after microbial spoilage), it is very likely they will migrate to your freezer.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-colour-coding-your-fridge-can-stop-your-greens-going-to-waste-45703">How colour-coding your fridge can stop your greens going to waste</a>
</strong>
</em>
</p>
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<h2>Help, my freezer smells!</h2>
<p>There are some simple steps you can take to stop your freezer from smelling.</p>
<p>First, try to prevent odours from developing in the first place by covering the food. If you place food in an airtight container (glass is best), it will dramatically slow the release of any aromatic compounds produced by bacteria or the food itself. Covered food is also less likely to absorb smells and flavours from other foods around it.</p>
<p>If the smells have already developed, you can eliminate them by following a few simple steps, including a thorough clean.</p>
<ul>
<li><p>Remove all items from the freezer and inspect the foods for any spoilage, freezer burn or unpleasant odours. </p></li>
<li><p>Discard anything that has developed ice crystals and store the rest in a cooler box while attending to the freezer itself. You should also inspect the fridge and discard any bad-smelling foods. </p></li>
<li><p>Once you have removed all items, take out the shelves and clean up spills or crumbs. </p></li>
<li><p>Wipe down all surfaces using warm soapy water or a mix of two tablespoons of baking soda with warm water.</p></li>
<li><p>Wash all the shelves and ice compartments and let them dry completely. </p></li>
</ul>
<p>If the smells are not removed with these simple cleaning steps, the freezer may require a deep clean, which involves turning off the unit and letting it “breathe” for a few days.</p>
<p>Placing some baking soda inside the freezer before adding food can help to absorb any residual odours. For serious smells where crevices or insulation are contaminated, you may need a service technician.</p>
<p>In short, even though we think freezers keep things “fresh”, microbes can still proliferate in there. Make sure to clean your freezer now and then to keep your food safe and healthy.</p><img src="https://counter.theconversation.com/content/203058/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Do your ice taste funny? Is there ‘freezer burn’ on your meat? This is why your freezer probably isn’t as clean as you think – but it only takes a few simple steps to fix it.Enzo Palombo, Professor of Microbiology, Swinburne University of TechnologyRosalie Hocking, Swinburne University of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2005862023-05-01T10:41:49Z2023-05-01T10:41:49ZPower cuts and food safety: how to avoid illness during loadshedding <figure><img src="https://images.theconversation.com/files/522112/original/file-20230420-201-bpqhqv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Keep as little food as possible in your fridge and freezer.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p><em>South Africa has been grappling with power cuts for <a href="https://www.myggsa.co.za/when-did-load-shedding-first-start-in-south-africa/">15 years</a>, which have <a href="https://www.resbank.co.za/content/dam/sarb/publications/quarterly-bulletins/boxes/2022/december/Measures%20of%20electricity%20load-shedding.pdf">worsened in recent years</a>. The persistent power outages have disrupted <a href="https://theconversation.com/africa/search?q=power+cuts">every facet of life</a>, including <a href="https://theconversation.com/your-fridge-might-not-be-cold-enough-to-keep-food-safe-70262">food safety</a>. The Conversation Africa’s Ina Skosana spoke to food safety expert Lise Korsten about the impact of persistent power cuts on the food in our homes and the best ways to protect ourselves.</em> </p>
<hr>
<h2>How should we manage the food in our fridges?</h2>
<p>The reality is that loadshedding for extended periods of time is causing temperature fluctuations in our fridges. Particularly if the fridge is regularly opened during loadshedding or if it has old rubber sealants. Temperature fluctuations can make food go bad. </p>
<p>To start with, let’s consider “what’s in our fridges”, “do we really need to keep so much perishable food in our fridges” and “how safe is it, given current loadshedding schedules”.</p>
<p>Loadshedding is forcing us to think about food safety and spoilage, our general behaviour in terms of food purchases, storage, managing our fridges, hygiene and the use of leftover food. </p>
<p>We need to ask ourselves: “are we buying more food than we should, and are we not wasting more food?”</p>
<p>Perhaps we should consider a more minimalist lifestyle if we are to survive the current economic downturn and manage the impact of loadshedding. </p>
<p>Keeping too much food in fridges increases the potential risk of food-borne illness given our current energy crises. In short, households need to better manage the food in fridges and keep as little of it as possible. </p>
<h2>What’s the best way to avoid illness?</h2>
<p>Keep your fridge – and kitchen – clean. Doing so will reduce the potential of organisms that can proliferate in these environments and cause illnesses, such as food poisoning. There are a few basic ways to maintain hygiene:</p>
<ul>
<li><p>regularly clean your fridge and keep a special eye on obvious potential contamination points such as areas where, for instance, the blood from raw meat dripped onto the bottom shelf </p></li>
<li><p>defrost your freezer to remove any ice building up that can affect the performance of the freezer. </p></li>
</ul>
<p>New fridges often maintain the temperature more effectively for longer periods of time due to new, well-fitting seals. If it’s an older fridge and the rubber seals are broken or the door doesn’t close properly, temperature fluctuations will more likely occur.</p>
<p>A good rule is also to keep your fridge closed during loadshedding and pack more higher risk items towards the back where less temperature fluctuations will occur. The door of the fridge is a higher risk area because of higher temperature fluctuations. This is important since we often keep milk in this compartment, thereby increasing the risk of it going off before the use-by date. </p>
<p>So set your fridge or freezer temperature correctly, and make sure it’s clean and fully functional. The key is keep the temperature consistent and manage the stocks in your fridge. </p>
<h2>Why does fridge temperature matter?</h2>
<p>We don’t get sick from just one organism. We get sick from a certain number of tiny organisms. What is important to keep in mind is that some microorganisms can multiply rapidly – in fact some every <a href="https://www.sciencedirect.com/science/article/abs/pii/B9780433101000500091">20 minutes</a>, others even every <a href="https://blogs.udla.edu.ec/haccp/2017/05/25/bacteria-and-how-they-multiply/#:%7E:text=In%20the%20right%20conditions%2C%20a,would%20have%20over%208%2C000%20bacteria.">10 minutes</a>. </p>
<p>Environmental conditions – such as fluctuating temperatures – will influence how many organisms are present at a certain point in time and can multiply. If the food is kept at temperatures that fluctuate it will encourage rapid growth of microorganism to levels high enough to cause illness by the time the food is consumed. </p>
<p>In general, microorganisms can multiply at temperatures between 4°C and 60°C. This temperature range is often called the “danger zone” in food safety. Some of these organisms prefer room temperature to rapidly multiply. Leaving food outside the fridge is, therefore, risky behaviour since you do not know if food is contaminated with any pathogens or if general spoilage can occur. The strategy is, therefore, to prevent contamination or “slow down” the growth of organisms through effective cold chain management. </p>
<p>The amount of microorganisms in food that can cause illnesses varies. It can be as little as <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2553879/">10 or 100 colony forming units</a> – the number of microbial cells in a sample that are able to multiply – per gramme of food. Some organisms can make us sick very quickly, even if only a few cells were initially present. Others increase in number over time when temperatures fluctuate, making food temperature management important. </p>
<p>It’s also important to remember that not all microorganisms are enemies. Less <a href="https://microbiologysociety.org/why-microbiology-matters/what-is-microbiology/microbes-and-the-human-body/microbes-and-disease.html">than 1%</a> actually make us sick. We need to understand the microbial balance in nature and manage the system to our benefit. </p>
<h2>Is it safe to eat leftovers?</h2>
<p>It’s interesting to mention <a href="https://journals.sagepub.com/doi/10.1177/0020872817742703">a study</a> where waste pickers were asked how they know when food is safe to eat. They explained reliance on basic skills and instinct, which in essence means sensory parameters: smelling if food is off, touch (that slimy feeling), that “look” (texture and offish) and memory – once you have been sick from a specific food item your body will instinctively react (almost like a shiver down the spine). </p>
<p>These instincts are important and are in a way a survival skill, so be stringent when keeping leftover food. If you do, try and consume it as soon as possible, preferably the next day. Also, if you heat something, do so properly. A golden rule is to avoid reheating food, especially not more than once. Keep in mind that microorganisms can survive high and low temperatures, and can rapidly multiply during the cooling down periods. So your timeline for safety gets less the longer you keep your food and expose it to fluctuating temperatures.</p>
<p>If possible, make sure you only prepare enough food for a meal, and try and keep fewer leftovers in your fridge. We should also start thinking about eating smaller portions and ask ourselves the question: do our bodies really need that volume of food? It is better, for our mind and soul, to be more conscious of using food wisely and wasting less. This is important in a country where a <a href="https://theconversation.com/south-africas-hunger-problem-is-turning-into-a-major-health-crisis-183736">very high percentage</a> of people go to bed hungry every night.</p>
<h2>So what to do?</h2>
<p>We all have time constraints, with the majority of people getting home late at night and having to rapidly prepare a healthy, safe meal. So plan meal portions, preparation and serving times around loadshedding, and manage the food in the fridge more wisely.</p><img src="https://counter.theconversation.com/content/200586/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lise Korsten 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>The era of stocking pantries and keeping our fridges and freezers full is over.Lise Korsten, Professor in the Department of Microbiology and Plant Pathology and Co-Director at the Centre of Excellence in Food Security, University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2015532023-03-16T19:11:18Z2023-03-16T19:11:18ZPFAS for dinner? Study of ‘forever chemicals’ build-up in cattle points to ways to reduce risks<figure><img src="https://images.theconversation.com/files/515054/original/file-20230314-2080-1forbm.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5424%2C3605&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>PFAS, known as “forever chemicals”, have been found just about <a href="https://www.ewg.org/interactive-maps/pfas_in_wildlife/map/">everywhere on Earth</a>, including in <a href="https://www.theguardian.com/environment/2023/mar/13/toxic-forever-chemicals-pfas-toilet-paper">toilet paper</a>.</p>
<p>These chemicals are a group of artificial compounds based on carbon and fluorine – per- and polyfluoroalkyl substances, or PFAS. They comprise thousands of individual chemicals with hundreds of documented uses, including <a href="https://doi.org/10.1039/D0EM00291G">water proofing and fire suppression</a>. It is likely every household has products or textiles that contain or were treated with a product that contained PFAS (including some <a href="https://theconversation.com/youve-read-the-scary-headlines-but-rest-assured-your-cookware-is-safe-199967">non-stick cookware</a> and stain-resistant fabrics). </p>
<p>Studies have shown most people have one or more <a href="https://doi.org/10.1016/j.envint.2014.05.019">PFAS compounds in their blood</a>. We live in a world full of chemicals, so why do we care about these ones? Well, some PFAS have been associated with a wide range of <a href="https://www.health.gov.au/sites/default/files/documents/2022/07/enhealth-guidance-health-effects-and-exposure-pathways-per--and-polyfluoroalkyl-substances-pfas.pdf">adverse human health effects</a>, such as cancer and immune problems. However, there is limited evidence of human disease resulting from environmental exposures. </p>
<p><a href="https://doi.org/10.1016/j.envres.2023.115518">Our study</a> investigated the uptake of PFAS into livestock at ten PFAS-impacted farms in Victoria. Our analysis also shows how risks can be reduced. </p>
<p>Our findings show the land and livestock can be managed to reduce PFAS levels in the animals before they enter the food chain. This means good management practices can protect food quality and reduce consumer exposure.</p>
<figure class="align-center ">
<img alt="Farmer closes the gate behind a herd of beef cattle" src="https://images.theconversation.com/files/515051/original/file-20230314-22-d1yrt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/515051/original/file-20230314-22-d1yrt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/515051/original/file-20230314-22-d1yrt0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/515051/original/file-20230314-22-d1yrt0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/515051/original/file-20230314-22-d1yrt0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/515051/original/file-20230314-22-d1yrt0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/515051/original/file-20230314-22-d1yrt0.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 bad news is PFAS builds up in cattle when their pasture or water is contaminated. The good news is the land and livestock can be managed to reduce the risks.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/pfas-might-be-everywhere-including-toilet-paper-but-lets-keep-the-health-risks-in-context-201785">PFAS might be everywhere – including toilet paper – but let's keep the health risks in context</a>
</strong>
</em>
</p>
<hr>
<h2>How do PFAS get in your blood?</h2>
<p>Exposure to household <a href="https://www.sciencedirect.com/science/article/pii/S0160412022000757?via%3Dihub">dust and consumption of contaminated food</a> or <a href="https://doi.org/10.1016/j.envres.2019.108648">water</a> are major contributors to human exposure to PFAS. It then <a href="https://doi.org/10.1016/j.envres.2019.108648;%20https://doi.org/10.1016/j.envint.2022.107149">accumulates in our blood</a>. </p>
<p>As the name would suggest, forever chemicals persist in the environment. As a result, when released into the environment, they disperse and over time can contaminate surrounding areas. </p>
<p>Firefighting and training activities have historically resulted in large releases of PFAS into the environment. This includes farming areas. </p>
<p>As livestock feed and drink from contaminated sources, this leads to PFAS accumulation in tissues. From there, PFAS can be transferred into the food chain, including products we eat such as <a href="https://doi.org/10.1016/j.scitotenv.2020.144795">meat and milk</a>. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/forever-chemicals-have-made-their-way-to-farms-for-now-levels-in-your-food-are-low-but-theres-no-time-to-waste-192402">'Forever chemicals' have made their way to farms. For now, levels in your food are low – but there's no time to waste</a>
</strong>
</em>
</p>
<hr>
<p>The causal links and what levels of PFAS exposure are harmful are <a href="https://nceph.anu.edu.au/research/projects/pfas-health-study#acton-tabs-link--tabs-0-footer-4">still being investigated</a>. The scientific community has yet to reach a consensus on how “bad” these compounds are, or conversely what the safe exposure levels are. </p>
<p>In the meantime, it is important to <a href="http://chm.pops.int/Implementation/IndustrialPOPs/PFAS/Overview/tabid/5221/Default.aspx">limit exposure through regulation</a>. Australia has adopted environmental and <a href="https://www.dcceew.gov.au/environment/protection/publications/pfas-nemp-2">health-based guideline values</a> for three PFAS of concern: perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS).</p>
<p>Australian food quality is high. In a 2021 study, scientists tested for 30 different PFAS in a broad range of Australian foods and beverages. Only one specific PFAS (PFOS) was detectable. It was found in just five out of 112 commonly consumed foods and beverages <a href="https://www.foodstandards.gov.au/publications/Documents/27th%20ATDS%20report.pdf">at levels below concern</a>. </p>
<p>These findings would suggest PFAS contamination is not an issue at most farms in Australia. The risks are likely to be higher from food produced at PFAS-contaminated sites. At such locations, PFAS can affect a range of foods, including <a href="https://www.efsa.europa.eu/en/efsajournal/pub/6223">eggs, vegetables and livestock</a>. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1571230263702683650"}"></div></p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/backyard-hens-eggs-contain-40-times-more-lead-on-average-than-shop-eggs-research-finds-187442">Backyard hens' eggs contain 40 times more lead on average than shop eggs, research finds</a>
</strong>
</em>
</p>
<hr>
<h2>What did the study investigate?</h2>
<p>We collated data from environmental investigations at ten PFAS-impacted farms in Victoria. This included testing about 1,000 samples of soil, water, pasture and livestock blood for concentrations of 28 types of PFAS. Our analysis also included information about farm practices, including livestock rotation, access to clean pasture and water. </p>
<p>We found:</p>
<ul>
<li><p>two specific PFAS compounds (PFOS and PFHxS) made up more than 98% of total PFAS detected in livestock blood</p></li>
<li><p>PFAS concentrations in water were correlated to concentrations in livestock blood, implying water was a critical exposure pathway, while the relationships between livestock and PFAS levels for soil and pasture were weaker</p></li>
<li><p>livestock exposure to PFAS varies over time and across paddocks. Seasonal patterns in PFAS blood concentrations were linked to seasonal grazing behaviours and the animals’ need for drinking water. </p></li>
</ul>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic showing how PFAS exposures in livestock vary according to farmland management practices" src="https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=412&fit=crop&dpr=1 600w, https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=412&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=412&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=518&fit=crop&dpr=1 754w, https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=518&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/515045/original/file-20230314-2603-vl3pg1.png?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">PFAS exposures in livestock vary according to farmland management practices.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1016/j.envres.2023.115518">Mikkonen et al 2023</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>What’s the next step?</h2>
<p>Environment Protection Authority Victoria (EPA) is leading research and policy to understand how environmental PFAS risks can be better managed. In this regard, EPA along with research partners, is working to develop predictive models to estimate PFAS accumulation in livestock over their lifetime. This research will help determine when a site is too contaminated for livestock production and which ones to prioritise for PFAS remediation in soil and water.</p>
<p>Ultimately, this will allow more effective management of PFAS accumulation and reduce the likelihood of having PFAS for dinner.</p><img src="https://counter.theconversation.com/content/201553/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Antti Mikkonen is an employee of EPA Victoria, in the role of Principal Health Risk Advisor for chemicals. This work is part of Antti's PhD research at the University of South Australia where his candidature was supported by the Australian Government, Department of Education, Skills and Employment Research Training Program scholarship.</span></em></p><p class="fine-print"><em><span>Mark Patrick Taylor is a full-time employee of EPA Victoria, appointed to the statutory role of Chief Environmental Scientist. He is also an Honorary Professor at Macquarie University. </span></em></p>Most food in Australia remains free of PFAS, but a new study has found it can build up in cattle on PFAS-affected farms. But there are ways to manage the land and livestock to reduce the risks.Antti Mikkonen, Principal Health Risk Advisor – Chemicals, EPA Victoria, and PhD Candidate, School of Pharmacy and Medical Sciences, University of South AustraliaMark Patrick Taylor, Victoria's Chief Environmental Scientist, EPA Victoria; Honorary Professor, School of Natural Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2004282023-03-07T13:43:36Z2023-03-07T13:43:36ZPancakes won’t turn you into a zombie as in HBO’s ‘The Last of Us,’ but fungi in flour have been making people sick for a long time<figure><img src="https://images.theconversation.com/files/513212/original/file-20230302-18-uldpy1.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1198%2C628&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A human fungal zombie from the TV show 'The Last of Us.'</span> <span class="attribution"><a class="source" href="https://imgix.bustle.com/uploads/image/2023/1/20/2c922756-5f33-430d-801b-995eec7dc0d1-the-last-of-us.jpg?w=1200&h=630&fit=crop&crop=faces&fm=jpg">Liane Hentscher/HBO</a></span></figcaption></figure><p>In the HBO series “<a href="https://www.hbo.com/the-last-of-us">The Last of Us</a>,” named after the popular video game of the same name, the flour supplies of the world are contaminated with a fungus called <em>Cordyceps</em>. When people eat pancakes or other foods made with that flour, the fungi grow inside their bodies and turn them into zombies. </p>
<p>As a <a href="https://scholar.google.com/citations?user=5iZjEckAAAAJ&hl=en&oi=ao">food scientist</a>, I study the effect of processing on the quality and safety of fruits and vegetables, including the flour used to make pancakes. While no one is going to turn into a zombie from eating pancakes in real life, flour is often contaminated with fungi that can produce mycotoxins that make people sick. Proper processing and cooking, however, can generally keep you safe. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/uLtkt8BonwM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">‘The Last of Us’ is premised on a pandemic that brings the world to an apocalyptic collapse.</span></figcaption>
</figure>
<h2>How common is fungi in flour?</h2>
<p>People have been eating bread made from wheat for <a href="https://www.bbc.com/news/science-environment-44846874">approximately 14,000 years</a> and cultivating wheat for <a href="https://sustainablefoodtrust.org/news-views/a-brief-history-of-wheat/">at least 10,000 years</a>. In 1882, “<a href="https://doi.org/10.7717%2Fpeerj.12346">drunken bread disease</a>” was first documented in Russia, where people reported dizziness, headache, trembling hands, confusion and vomiting after eating bread. Long before that, Chinese peasants were reporting that eating pinkish wheat – a key sign of infection with a mold called <em>Fusarium</em> – caused them to feel ill. Clearly, fungi have been making people sick for a long time.</p>
<p>Wheat, corn, rice and even fruits and vegetables can be infected with fungi as they grow in the field. In “The Last of Us,” an epidemiologist theorizes that climate change is causing the fungus to mutate so it can infect humans. The unfortunate reality is that fungi have become more of a problem in recent years as <a href="https://doi.org/10.3389/fcimb.2018.00060">warmer temperatures</a> encourage their growth. </p>
<p><a href="https://doi.org/10.1111/jfs.12422">A 2017 study</a> found that over 90% of wheat and corn flour samples in Washington, D.C., contained live fungi, with <em>Aspergillus</em> and <em>Fusarium</em> the predominant types of mold in wheat flour. <em>Fusarium</em> grows on wheat in the field and can cause a common agricultural plant disease called <a href="https://ahdb.org.uk/knowledge-library/fusarium-and-microdochium-in-cereals">fusarium head blight</a>, or scab. </p>
<p>Farmers use <a href="https://open.alberta.ca/publications/fusarium-head-blight-of-barley-and-wheat">multiple techniques</a> to reduce this devastating plant disease, including implementing crop rotation, using resistant varieties and fungicides and minimizing irrigation during flowering. After harvesting, they sort the grains to remove contaminated wheat before grinding them into flour. While sorting removes most of the contaminated wheat, small amounts of fungi can still make it into the flour.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Pink wheat stalks infected with fusarium head blight" src="https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513399/original/file-20230303-29-cz1zd4.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">Wheat infected with fusarium head blight have a characteristic pink hue.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/fusarium-ear-blight-fusarium-head-blight-fhb-or-royalty-free-image/1358429685">Tomasz Klejdysz/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<h2>Killing microorganisms in flour</h2>
<p>The good news is that most fungi and other microorganisms <a href="https://www.ars.usda.gov/ARSUserFiles/60701000/FoodSafetyPublications/p328.pdf">die at 160-170 degrees Fahrenheit</a> (71-77 degrees Celsius). Pancakes are typically cooked to an internal temperature of <a href="https://www.lafujimama.com/oven-baked-pancake/">190-200 F</a> (88-93 C). Other cakes and breads are cooked to internal temperatures <a href="https://blog.thermoworks.com/bread/baked-good-doneness-temps/">anywhere from 180 to 210 degrees Fahrenheit</a> (82-99 C). So, unlike in “The Last of Us,” as long as you bake or fry your dough, you’ll have killed the fungi.</p>
<p>The problem comes when people eat the flour without cooking it first, such as by consuming raw cookie dough or “licking the bowl clean.” Both raw egg and raw flour can contain microorganisms that make people sick. The microorganisms that public health officials are most worried about are <a href="https://www.cdc.gov/foodsafety/communication/ecoli-and-food-safety.html"><em>E. coli</em></a> and <a href="https://www.cdc.gov/foodsafety/communication/salmonella-food.html"><em>Salmonella</em></a>, dangerous pathogens that can cause severe illness. </p>
<p>Most people don’t realize that the flour they buy at the store is raw flour that still contains live microorganisms. Flour is rarely commercially treated to be safe to eat raw because consumers almost always cook flour-based foods. While consumers can also attempt to heat-treat raw flour at home, <a href="https://ag.purdue.edu/stories/home-kitchen-heat-treated-flour-doesnt-protect-against-foodborne-illnesses-purdue-food-scientist-says/">this isn’t recommended</a> because the flour may not be spread thinly enough to kill all of the microorganisms.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Microscopy image of _Aspergillus_" src="https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513408/original/file-20230303-20-m292l6.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"><em>Aspergillus</em> is one of the predominant molds found in wheat flour.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/aspergillus-under-the-light-microscopic-view-for-royalty-free-image/1332594729">tonaquatic/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<p>Some fungi and microorganisms can create spores, which are like seeds that help them survive adverse conditions. These spores can survive cooking, drying and freezing. There are even <a href="https://www.smithsonianmag.com/smart-news/bread-was-made-using-4500-year-old-egyptian-yeast-180972842/">4,500-year-old yeast spores</a> that have been reawakened and made into bread. These fungal spores rarely cause serious illness in people, except in those with <a href="https://doi.org/10.1101%2Fcshperspect.a019273">weakened immune systems</a>.</p>
<p><a href="https://doi.org/10.3390%2Fmicroorganisms5030037">Chemicals can be added to food</a> to stop fungal growth. These additives include sorbates, benzoates and propionates. However, you almost never see these additives in flour or pancake mix because fungi can’t grow in a dry powder. The fungi either grew on the wheat in the field or on the bread after it is baked. For that reason, you may see these additives in bread but not in a powdered mix.</p>
<h2>Mycotoxins</h2>
<p>The biggest risk from fungi is not that it will grow inside our bodies, but that it will grow on wheat or other foods and produce <a href="https://doi.org/10.5487%2FTR.2019.35.1.001">chemicals called mycotoxins</a> that can cause severe health problems. When wheat is harvested and ground into flour, mycotoxins can get mixed in. </p>
<p>Unfortunately, while normal cooking can kill the microorganisms, it <a href="https://doi.org/10.5487%2FTR.2019.35.1.001">doesn’t destroy the mycotoxins</a>. Eating mycotoxins can cause problems ranging from hallucinations to vomiting and diarrhea to cancer or death. Some of the <a href="https://doi.org/10.1111/jfs.12422">common mycotoxins</a> found in grain include aflatoxins, deoxynivalenol, ochratoxin A and fumonisin B.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Moldy pastry on a plate" src="https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/513410/original/file-20230303-22-5r5j15.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It might be best to leave that moldy bread alone.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/moldy-inedible-spoiled-food-pasty-with-mold-in-a-royalty-free-image/1167797155">Yulia Naumenko/Moment via Getty Images</a></span>
</figcaption>
</figure>
<p>The oldest known case of mycotoxin poisoning is recorded as a <a href="https://doi.org/10.1021/acs.jafc.6b04494">disease called ergotism</a>. Ergotism was mentioned in the Old Testament and has been reported in Western Europe since A.D. 800. It has even been suggested that the <a href="https://www.vox.com/2015/10/29/9620542/salem-witch-trials-ergotism">Salem witch trials</a> were caused by an outbreak of ergotism that led its victims to hallucinate, though many have disputed this idea. Wheat is <a href="https://doi.org/10.1007/s11356-021-12671-w">less likely</a> than other grains to have dangerous mycotoxins, which is why some have proposed that declining mortality in 18th-century Europe, <a href="https://doi.org/10.1017/s0025727300034116">especially in England</a>, was due to the switch from a rye-based diet to a wheat-based diet.</p>
<p>Ultimately, you don’t need to worry about eating those pancakes. Farmers use many techniques to minimize fungal growth and remove moldy grain, and the government keeps a close eye on mycotoxin levels during crop production and storage. Just make sure you cook your bakery products before eating, and don’t eat anything that has started to mold.</p><img src="https://counter.theconversation.com/content/200428/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sheryl Barringer 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>Raw flour at the store still contains live microorganisms. And while cooking can kill the fungi, it doesn’t destroy any illness-causing mycotoxins that might be present.Sheryl Barringer, Professor of Food Science and Technology, The Ohio State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1999672023-02-21T19:02:23Z2023-02-21T19:02:23ZYou’ve read the scary headlines – but rest assured, your cookware is safe<figure><img src="https://images.theconversation.com/files/511285/original/file-20230221-2779-sjcfv9.jpg?ixlib=rb-1.1.0&rect=60%2C0%2C6720%2C4476&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>“Are nonstick pans toxic”? “Can aluminium cookware cause dementia?” “Are my scratched pans still safe?” That’s just a sample of a few worrying headlines about the safety of our pots and pans recently. </p>
<p>These stories often crop up in the media, and it’s easy to see why. We use our cookware every day. We want it to be safe. So are these concerns legitimate? </p>
<p>Good news for those who worry: the main chemical of concern used to make nonstick pans has been phased out. And aluminium is not linked to dementia. </p>
<p>If you are shopping for new kitchenware, you’ll find there’s now a lot of choice in material, such as cast iron, stainless steel, copper, non-stick and ceramic. By and large, they are all safe. </p>
<p>The choice over which is best depends on what type of cook you are, not on the health risks from the material. </p>
<h2>Nonstick pans: levels of forever chemicals are safe</h2>
<p>Nonstick pans are very popular because food is less likely to stick to their coating. That means you need less oil. They’re also easier to clean than, say, cast iron pans. </p>
<p>Most nonstick pans are coated with Teflon, the brand name for polytetrafluoroethylene (PTFE), though some are now being made with a titanium-ceramic coating. </p>
<p>If you’ve looked into cookware health risks, nonstick pans usually feature at the top of the list. That’s due to concerns about their use of “forever chemicals” such as PTFE. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Nonstick pan being bought" src="https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/511286/original/file-20230221-20-9fwj95.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">Nonstick pans have long been popular - and the main chemical of concern is long gone.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Forever chemicals is the common phrase for per- and poly-fluoroalkyl substances (PFAS), a family of man-made chemicals based on carbon-fluorine bonds. </p>
<p>These chemicals became notorious after the 2019 film Dark Waters, which tells the story of an American town <a href="https://slate.com/culture/2019/11/dark-waters-accuracy-fact-vs-fiction-teflon-dupont.html">contaminated</a> with the forever chemical perfluorooctanoic acid (PFOA). </p>
<p>The concern many have about nonstick cookware is because before 2013, PFOA was used to make Teflon. But it’s been a decade and this is <a href="https://www.healthline.com/nutrition/nonstick-cookware-safety#teflon-and-pfas">no longer</a> the case. Even when PFOA was used in pans it posed <a href="https://www.webmd.com/food-recipes/is-teflon-coating-safe">little risk</a>, and neither does Teflon.</p>
<p>Forever chemicals have been around since the 1940s, used in Teflon as well as food packaging, waterproof textiles, and firefighting foams. There are very real concerns about firefighting foams, which have caused widespread environmental pollution, particularly on <a href="https://www.theguardian.com/australia-news/2020/feb/27/pfas-class-action-settled-over-toxic-firefighting-foam-at-three-australian-defence-bases">army bases</a> and <a href="https://www.abc.net.au/news/2022-09-26/mick-tisbury-12-year-fight-to-protect-firefighters/101392332">firefighting training facilities</a> in Australia. People affected have launched legal action over contamination, worried over potential links to cancer, liver damage, and lowered immunity in children. </p>
<p>So why are forever chemicals like PTFE safe in our cookware? </p>
<p>Two reasons: stability and concentration.</p>
<p>Teflon is stable in cookware, even when heated to the temperatures commonly used in cooking. It begins to deteriorate if heated over 260°C when it may release polymer fumes but most people don’t fry their dinner at 260°C.</p>
<p>Not only that, the concentration levels of these chemicals in your kitchen and the environment are far lower than those found to cause <a href="https://www.sciencedirect.com/science/article/pii/S0045653520315332">health effects</a>. Heavily contaminated sites are very different to your well-manufactured pots and pans. </p>
<p>If your non-stick pan is scratched, it may be a good idea to replace it but you aren’t going to get a damaging dose of PFAS from dinner.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-blanket-ban-on-toxic-forever-chemicals-is-good-for-people-and-animals-127879">A blanket ban on toxic 'forever chemicals' is good for people and animals</a>
</strong>
</em>
</p>
<hr>
<h2>Aluminium pans: Can they cause dementia?</h2>
<p>There’s no strong evidence supporting fears aluminium exposure causes any kind of dementia, including Alzheimer’s disease. </p>
<p>So where did the idea come from? </p>
<p>In 1965, scientists discovered that feeding rabbits very high levels of aluminium produced changes in the rabbits’ brains resembling Alzheimer’s. This was later proven to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4131942/">be incorrect</a>.</p>
<p>There have also been <a href="https://www.alzheimers.org.uk/about-dementia/risk-factors-and-prevention/metals-and-dementia">reports</a> the brains of some people with dementia had high levels of metals such as aluminium. But no-one has found a link. </p>
<p>That’s probably where <a href="https://www.alz.org/alzheimers-dementia/what-is-alzheimers/myths">this myth</a> came from. Even though there’s no credible evidence for this, it’s led some people to avoid aluminium cookware – and even drink cans. </p>
<p>That’s a shame, as aluminium cookware heats up very rapidly and is lightweight and cheap. There have been issues with plain aluminium reacting to acidic and alkaline foods, or warping in the heat. You can largely avoid these – and put any residual health concerns to rest – by choosing <a href="https://www.drweil.com/diet-nutrition/cooking-cookware/anxious-about-anodized-aluminum/">anodised aluminium</a> cookware. </p>
<h2>Are copper pans safe?</h2>
<p>Copper is famously gorgeous. There’s something about seeing burnished copper cookware twinkling on the shelf. But it’s not all aesthetics – copper is an excellent conductor of heat and tends to heat the pot or pan evenly. That’s useful for delicate dishes requiring fine temperature control. It’s why you’ll often see copper pans used by professional chefs. </p>
<p>What about your health? If you eat food laced with high levels of copper, you can get nausea, vomiting and even liver damage. But that’s not going to happen from your pots or pans – you’ll get trace elements at best. (You also need small amounts of copper as an essential nutrient). </p>
<p>And most copper cookware has a non-reactive lining like stainless steel or tin, preventing traces of copper from getting into food.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="copper pans" src="https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/511288/original/file-20230221-2556-tahuq4.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">Chefs often like copper for its temperature control.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>What about cast iron, stainless steel or ceramic cookware?</h2>
<p>Cast iron, stainless steel and ceramic cookware are all good options, as they’re usually durable, non-reactive, and easy to clean. </p>
<p>Downsides? Cast iron is heavy and may not heat evenly. Some ceramics can be damaged quite easily, though most modern varieties are very strong. </p>
<p>In cheap stainless steel pans, nickel and other metals could potentially leach out of the pan and into your meal but it’s very unlikely unless the manufacturer is cutting corners and using low-quality stainless steel. </p>
<p>By and large, all three are good choices if they are from reputable manufacturers. </p>
<h2>So why do we worry about chemicals and metals in our cookware?</h2>
<p>We’re often bad at assessing risk. The more we hear about an alleged risk, the more dangerous we tend to think it is – even when the actual risk is low. Fear of chemicals – <a href="https://www.canr.msu.edu/news/chemophobia-fearing-chemicals">chemophobia</a> – is common, but many of these fears are unnecessary. The painkiller you took for your hangover was a chemical, as is the fuel in your car. </p>
<p>In short, your cookware is safe. Enjoy your dinner. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/seven-ways-to-protect-your-health-when-cooking-with-gas-199428">Seven ways to protect your health when cooking with gas</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/199967/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Oliver A.H. Jones does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The steady stream of stories in the media about unsafe cookware might make you wary. But your pots and pans are almost certainly safe.Oliver A.H. Jones, Professor, RMIT UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1927232023-01-05T20:37:28Z2023-01-05T20:37:28ZNo, you shouldn’t wash raw chicken before cooking it. So why do people still do it?<figure><img src="https://images.theconversation.com/files/490251/original/file-20221018-17274-k1s6c8.jpg?ixlib=rb-1.1.0&rect=0%2C18%2C6256%2C4108&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Food safety authorities and regulators <a href="https://foodsafety.asn.au/topic/tips-poultry/">around</a> <a href="https://www.cdc.gov/foodsafety/chicken.html#:%7E:text=after%20handling%20chicken.-,Do%20not%20wash%20raw%20chicken.,that%20previously%20held%20raw%20chicken.">the</a> <a href="https://www.food.gov.uk/safety-hygiene/cleaning">world</a> <a href="https://www.mpi.govt.nz/food-safety-home/preparing-and-storing-food-safely-at-home/clean-cook-chill/#:%7E:text=Don't%20wash%20raw%20chicken,food%20poisoning%20from%20campylobacter%20bacteria.">recommend</a> you don’t wash raw poultry before cooking. </p>
<p>That’s because washing chicken can splash dangerous bacteria around the kitchen. It’s best just to thoroughly cook the chicken without washing it, so it is safe to eat.</p>
<p>Despite this, chicken-washing remains common. A <a href="https://www.safefood.qld.gov.au/newsroom/does-raw-chicken-need-rinsing/">survey</a> by Australia’s Food Safety Information Council showed almost half of Australian home cooks washed whole chickens before cooking. Dutch research found <a href="https://www.foodsafetynews.com/2022/05/dutch-survey-finds-a-quarter-of-people-wash-chicken-despite-expert-advice/">25%</a> of consumers washed their chicken often or almost always.</p>
<p>So why do people do it – and what does the research say about the risks of chicken-washing?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.jpg?ixlib=rb-1.1.0&rect=0%2C48%2C5391%2C3535&q=45&auto=format&w=1000&fit=clip"><img alt="A person washes chicken over a sink." src="https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.jpg?ixlib=rb-1.1.0&rect=0%2C48%2C5391%2C3535&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/490247/original/file-20221017-18129-wt6pzf.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">Australia’s Food Safety Information Council recommends raw poultry not be washed before cooking.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/yes-you-can-reheat-food-more-than-once-heres-why-184158">Yes, you can reheat food more than once. Here's why</a>
</strong>
</em>
</p>
<hr>
<h2>Chicken meat and germs</h2>
<p>Incorrect cooking temperatures and cross-contamination between different foods are two of the most important factors linked to foodborne illness. </p>
<p>This is particularly relevant to poultry meat. Two leading causes of foodborne illness are the bacteria <em><a href="https://www.cdc.gov/campylobacter/index.html">Campylobacter</a></em> and <em><a href="https://www.cdc.gov/foodsafety/communication/salmonella-food.html">Salmonella</a></em>, which are commonly found on raw poultry. </p>
<p>In Australia, reported cases of <em>Campylobacter</em> and <em>Salmonella</em> have almost <a href="https://foodsafety.asn.au/topic/tips-poultry/">doubled</a> over the last two decades. </p>
<p>Of the estimated 220,000 cases of <em>Campylobacter</em> infection each year, <a href="https://foodsafety.asn.au/topic/tips-poultry/">50,000</a> can be attributed either directly or indirectly to chicken meat. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Chicken is grilled on a barbecue." src="https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/491574/original/file-20221025-19-osvds4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Why do many home cooks continue to wash chicken before cooking?</span>
<span class="attribution"><a class="source" href="https://www.pexels.com/photo/barbecue-bbq-beef-chicken-262945/">Photo by Pixabay</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Chicken-washing myths, busted</h2>
<p>One <a href="https://doi.org/10.1016/j.foodcont.2020.107682">analysis</a> of consumer responses to an education campaign about the dangers of washing raw poultry shed light on why many people still wash raw chicken before cooking.</p>
<p>Some believe there is a need to wash faeces and other matter off the chicken meat. In fact, modern processing techniques mean chicken carcasses do not need additional cleaning. </p>
<p>Others believe washing with a slightly acidic solution (such as vinegar or lemon juice) will kill bacteria. </p>
<p>On the contrary, <a href="https://doi.org/10.1016/j.foodcont.2018.06.034">research</a> has shown washing raw poultry in lemon juice or vinegar does not remove bacteria and can increase the cross-contamination risk.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1519397720200339456"}"></div></p>
<h2>Washing chicken splashes bacteria around</h2>
<p>One of the more compelling arguments why washing raw poultry under a running tap is a risky activity comes from <a href="https://doi.org/10.1063/5.0083979">recent research</a> on water droplets ejected from the surface of washed chicken. </p>
<p>The study clearly showed bacteria can be transferred from the surface of the chicken to surrounding surfaces via water droplets.</p>
<p>Using high-speed imaging, the researchers found a higher tap height can increase splashing. </p>
<p>Chicken meat is often soft and the water flow can create a divot in the surface. This leads to splashing that would not occur on a curved, hard surface. </p>
<p>The researchers placed large agar plates next to the chicken surfaces to capture any water droplets. This allowed them to grow the bacteria that were transferred with the splashed water. </p>
<p>They found the level of bacterial transmission increased with greater tap height and water flow rate. </p>
<p>Aerated water (which is what you get when the tap is running very hard) also increased splashing and bacterial transmission. </p>
<h2>What if I still really want to wash my chicken meat?</h2>
<p>While washing raw poultry is not recommended, it appears some home cooks are reluctant to let go of this old habit. </p>
<p>If you insist on washing chicken meat, consider doing so in a sink of water rather than under a running tap.</p>
<p>Use a paper towel to mop up any liquids, dispose of the towel and clean up afterwards. </p>
<p>This will help reduce the risk of cross-contamination and keep the kitchen safe. And please wash your hands after handling raw meat! </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-when-should-you-throw-away-leftovers-92256">Health Check: when should you throw away leftovers?</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/192723/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Enzo Palombo 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>Washing raw chicken can splash bacteria around the kitchen. It’s best just to properly cook the chicken without washing it. So why do people still wash? Time to bust some chicken-washing myths.Enzo Palombo, Professor of Microbiology, Swinburne University of TechnologyLicensed 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/1967212022-12-19T13:36:24Z2022-12-19T13:36:24ZThe lenses of fishes’ eyes record their lifetime exposure to toxic mercury, new research finds<figure><img src="https://images.theconversation.com/files/501636/original/file-20221216-18-9nfdr9.jpg?ixlib=rb-1.1.0&rect=42%2C0%2C3983%2C3024&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">When fish like this netted cod are exposed to mercury, it accumulates in certain organs, including the lenses of their eyes.</span> <span class="attribution"><span class="source">Yvette Heimbrand</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Mercury pollution is a global threat to human health, especially to unborn babies and young children. Exposure to <a href="https://www.epa.gov/mercury/how-people-are-exposed-mercury">methylmercury</a>, a type that forms when mercury washes into lakes and streams, can <a href="https://doi.org/10.1002/msj.20228">harm children’s brain development</a> and cause symptoms including <a href="https://www.epa.gov/mercury/health-effects-exposures-mercury">speech impairment and muscle weakness</a> in adults who consume seafood as their main food source. Methylmercury also threatens health and reproduction in <a href="https://blogs.ifas.ufl.edu/news/2020/10/26/new-study-on-mercury-contamination-has-global-implications-for-wildlife-conservation/">fish and other wildlife</a>.</p>
<p>Humans, animals and birds are exposed to methylmercury when they eat fish and shellfish. Scientists have been working for decades to understand how and when fish accumulate mercury. This information is key for assessing mercury risks across different water bodies and landscapes, and for evaluating <a href="https://www.epa.gov/mercury/what-epa-doing-reduce-mercury-pollution-and-exposures-mercury">policy changes designed to reduce mercury emissions</a>.</p>
<p>For decades, scientists have used fish ear stones, known as otoliths, to gain insights into fish growth, migration, diet and the timing of their exposure to certain pollutants. These tiny structures of calcium carbonate, roughly the size of a pea, form inside fishes’ inner ears, where they help regulate hearing and balance. Otoliths can also provide clues about <a href="https://theconversation.com/how-is-climate-change-affecting-fishes-there-are-clues-inside-their-ears-110249">how climate change is affecting fish</a>.</p>
<p>But some pollutants, including mercury, are not incorporated into otoliths. Rather, they bind very strongly to tissues that contain sulfur, such as muscle tissues. That’s why muscle tissues have historically been used to assess contamination due to mercury pollution.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two small oval stones in a petri dish with two round eye lenses." src="https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/501627/original/file-20221216-12-jdaenu.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">Fish otoliths (above) and eye lenses (below) reveal complementary information about fish life history.</span>
<span class="attribution"><span class="source">Karin Limburg</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>In a newly published study, we describe a new window into individual fish’s lifetime exposure to mercury by <a href="http://dx.doi.org/10.1021/acs.estlett.2c00755">measuring it in the fish’s eyes</a>. This work is unlocking new possibilities for understanding fish lifetime exposure to this potent neurotoxicant.</p>
<h2>Clues in fish ears and eyes</h2>
<p>Today, scientists analyze mercury uptake in fish by measuring how much of it accumulates in whole bodies of fish, or often just in fillets – that is, muscle tissues. This approach tells us how much mercury the fish has accumulated over its lifetime, but it doesn’t tell us specifically when in its life the fish was exposed. A time stamp is missing.</p>
<p>Mercury concentrations can vary widely within any given fish species. For example, from 1991 to 2010, U.S. government monitors detected <a href="https://www.fda.gov/food/metals-and-your-food/mercury-levels-commercial-fish-and-shellfish-1990-2012">mercury levels in cod</a> that averaged 0.111 parts per million but ranged as high as 0.989 parts per million, a ninefold difference. This suggests that in addition to changes in mercury emissions over time, an individual fish’s movements and diets can significantly affect its exposure. </p>
<p>In our study, we propose a new method that combines measurements of otolith aging and of mercury in the lenses of a fish’s eyes to assign ages to fish eye mercury concentrations. Eye lenses are made of pure protein, are high in sulfur content and thus readily take up mercury either <a href="https://doi.org/10.1021/cb4004805">directly from water</a> or from the fish’s diet. </p>
<p>Methylmercury appears to be preferentially taken up in certain organs, <a href="https://www.doi.org/10.1073/pnas.0803147105">including eye lenses</a>. At high doses, it <a href="https://doi.org/10.1016/j.marenvres.2015.10.015">may impair fish vision</a>.</p>
<p>Our approach starts with the well-established technique of aging a fish using its otolith. As a fish grows and ages, its otoliths add yearly layers of calcium carbonate. We can estimate the fish’s age and growth rates by measuring the distance between the yearly growth layers, which are called annuli, much as foresters date trees by measuring the growth rings in their trunks. </p>
<p>We also know that a fish’s eye grows at a rate that is proportional to the growth of its otolith. So in our analysis, we apply the proportional distance that we found in the fish’s otolith to its eye lens. For our focal species, the Round Goby (<em>Neogobius melanostomus</em>), the linear relationship between these two measurements is strong. </p>
<p>As the eye lens grows and accumulates mercury, we can pinpoint when the fish was exposed using this correspondence with the otolith. And because the fish’s eye lens grows in layers throughout life, we can follow the chronology of lifetime exposure.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cross-section of a catfish eye lens and graphic showing mercury exposure as recorded in the lens" src="https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=866&fit=crop&dpr=1 600w, https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=866&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=866&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1089&fit=crop&dpr=1 754w, https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1089&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/501628/original/file-20221216-16-cm75i8.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1089&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An eye lens of a brown bullhead catfish (top) sliced into a cross section that shows the core, formed at birth, and the layers that grow throughout life. The lower image shows the spatial pattern of the element mercury in the same lens, analyzed at the Cornell High Energy Synchrotron Source. Note that concentrations are at background levels in the layers deposited when this fish was young and increased as it got older and began to consume other fish.</span>
<span class="attribution"><span class="source">Karin Limburg</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>A possible climate connection</h2>
<p>With this new method, we can start to trace the chronology of a fish’s lifetime mercury exposure. And we can ask questions about how life history events, such as migration and diet shifts, or temporal events such as <a href="https://www.epa.gov/ms-htf/northern-gulf-mexico-hypoxic-zone">low dissolved oxygen levels in water</a> at certain times of year, may influence a fish’s mercury levels.</p>
<p>The strength of this method is that it provides information for individual fish, which matters just as it does for humans. Different individual fish have varying abilities to catch prey and avoid or tolerate stress, all of which can affect their growth and exposure to mercury. </p>
<p>And having information about mercury exposure for all ages of a single fish can help decrease the need to collect large samples of many fish across all ages, which is how scientists traditionally have assessed how fishes’ exposure changes over their lifetimes.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1179802840728051712"}"></div></p>
<p>This new method may also help us understand how climate change is affecting mercury exposure.</p>
<p>As water temperatures rise, rivers, lakes, estuaries and oceans are losing some of their dissolved oxygen. This process, known as <a href="https://scripps.ucsd.edu/research/climate-change-resources/faq-ocean-deoxygenation">deoxygenation</a>, is a critical stressor for aquatic life. </p>
<p>When oxygen in a pond or bay falls below 2 milligrams per liter, compared with normal levels of 5 to 8 milligrams per liter, that water body is said to be hypoxic – and hypoxic conditions can be associated with elevated concentrations of methylmercury. This loss of oxygen is exacerbated by <a href="https://oceanservice.noaa.gov/hazards/hypoxia/#">nutrient pollution</a> – for example, from urban or agricultural runoff. But it can also occur in the open oceans, far from continents, due to warming.</p>
<p>Increasing hypoxia could negate <a href="https://www.mercuryconvention.org/en">recent global efforts to reduce mercury emissions</a> by making the mercury that is already in lakes and oceans more available for uptake into fish. However, fish response to hypoxia can vary by individual and by species. Our current research, sponsored by the National Science Foundation, is exploring how fish eye lenses, together with otoliths, can help us disentangle exposure to mercury from diet and hypoxia. </p>
<p>Increasingly, scientists are recognizing that various body parts of organisms function as archives of the past. For us, eye lenses and otoliths serve as key means to understand the secret lives of individual fish.</p><img src="https://counter.theconversation.com/content/196721/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Roxanne Razavi receives funding from the U.S. National Science Foundation. </span></em></p><p class="fine-print"><em><span>Hadis Miraly is supported by funding from the U.S. National Science Foundation. </span></em></p><p class="fine-print"><em><span>Karin Limburg receives funding from the U.S. National Science Foundation, which sponsored this research. </span></em></p>A new study shows that a time stamp can be put on mercury that accumulates in fish eyes, offering a window into their lifetime exposure.Roxanne Razavi, Assistant Professor of Environmental Biology, State University of New York College of Environmental Science and ForestryHadis Miraly, PhD Candidate in Environmental Biology, State University of New York College of Environmental Science and ForestryKarin Limburg, Distinguished Professor of Environmental Biology, State University of New York College of Environmental Science and ForestryLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1947162022-11-17T03:58:49Z2022-11-17T03:58:49ZToxic poppy seeds are sending people to hospital. 3 experts explain what’s behind the latest food scare<figure><img src="https://images.theconversation.com/files/496004/original/file-20221117-17-madsvi.jpg?ixlib=rb-1.1.0&rect=4%2C1%2C994%2C664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Poisonous poppy seeds have sent a number of people around Australia to hospital with severe symptoms – from muscle cramping and spasms to seizures and cardiac arrests – prompting a nationwide recall of <a href="https://www.foodstandards.gov.au/media/Pages/Additional-brands-listed-in-national-poppy-seed-recall.aspx">certain batches and brands</a> of this common pantry item.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1592706604905873408"}"></div></p>
<p>We work for two major poisons information services (<a href="https://www.health.nsw.gov.au/news/Pages/20221115_00.aspx">New South Wales</a> and <a href="https://www.childrens.health.qld.gov.au/chq/our-services/queensland-poisons-information-centre/">Queensland</a>), where we have been advising and caring for people with poppy seed poisoning. There have also been cases in <a href="https://www.health.vic.gov.au/health-alerts/health-warning-on-on-poppy-seeds">Victoria</a>, Australian Capital Territory, <a href="https://glamadelaide.com.au/urgent-recall-on-two-popular-poppy-seed-brands-amid-poisoning-concerns/">South Australia</a> and <a href="https://ww2.health.wa.gov.au/Media-releases/2022/November/WA-Health-warns-community-of-severe-reactions-after-consuming-poppy-seed-tea">Western Australia</a>. </p>
<p>To date, there have been around 32 cases of poppy seed toxicity reported in Australia over the past month, all in adults.</p>
<p>This is what we know about what’s behind these cases and what you need to do if you’ve consumed poppy seeds recently, or have poppy seeds in your kitchen cupboards.</p>
<hr>
<p>
<em>
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Read more:
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</strong>
</em>
</p>
<hr>
<h2>How could these poppy seeds be dangerous?</h2>
<p>The poppy seeds involved in the latest national recall are non-food grade seeds that are not intended for human consumption and are not safe to consume. Investigations are under way to determine how non-food grade seeds ended up in the shops.</p>
<p>Food-grade poppy seeds – the type that you’d usually see sprinkled on cake or bread – are not dangerous.</p>
<p>Poppy seeds come from the poppy plant <em>Papaver somniferum</em>. This plant produces a number of chemicals called alkaloids. Some, like morphine and codeine, have been used medicinally for thousands of years to treat pain and other conditions.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Poppy plant Papaver somniferum" src="https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=413&fit=crop&dpr=1 600w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=413&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=413&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=520&fit=crop&dpr=1 754w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=520&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/495762/original/file-20221116-13-cv3jy9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=520&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Poppy seeds come from the plant <em>Papaver somniferum</em> and are used to make medicines, as well as food products.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/opium-poppy-heads-close-papaver-somniferum-2004569264">Shutterstock</a></span>
</figcaption>
</figure>
<p>Other naturally occurring poppy alkaloids – such as thebaine, noscapine, laudanosine and papaverine – are less-well described in terms of their effects on humans, but they can have a wide range of toxic effects.</p>
<p>Different varieties of poppy plants contain different amounts of these alkaloids.</p>
<p>Some have very low amounts, which tend to be used to produce food-grade poppy seeds. Varieties with higher amounts are used to produce medicines, such as morphine and codeine.</p>
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<p>
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</strong>
</em>
</p>
<hr>
<h2>What happened recently then?</h2>
<p>The non-food grade poppy seeds that incorrectly entered the human food supply contain high amounts of the alkaloid thebaine. </p>
<p>Thebaine has very different effects to morphine. <a href="https://pubmed.ncbi.nlm.nih.gov/31670127/">In large doses</a> it causes severe and prolonged muscle cramps, spasms, seizures and cardiac arrests, as seen in the recent cluster of poisonings. </p>
<p>High concentrations of thebaine have been identified in the blood of affected people in this latest cluster.</p>
<p>To our knowledge, this is the first time that thebaine has entered the food chain in Australia. However, there are a couple of reports of people who have had severe toxicity after consuming non-food grade poppies in recent decades.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/indian-viagra-herbal-drug-kamini-contains-morphine-and-can-quickly-lead-to-dependence-191509">'Indian Viagra' – herbal drug Kamini contains morphine and can quickly lead to dependence</a>
</strong>
</em>
</p>
<hr>
<h2>How many poppy seeds are we talking about?</h2>
<p>All reported cases in the current cluster at the time of the recall occurred after people consumed poppy seeds as part of a drink – similar to a brewed tea. </p>
<p>Most people had consumed more than 100g poppy seeds (about 11 tablespoons). Although, 50g (5-6 tablespoons) may be sufficient to cause poisoning. Thebaine can build up in the body if you ingest it several times over the same day.</p>
<p>There have been no reports to date of people being poisoned after eating poppy seeds in baked goods. However, the investigation is ongoing. Owing to the nature of the contamination, we’d recommend avoiding poppy seeds from <a href="https://www.foodstandards.gov.au/media/Pages/Additional-brands-listed-in-national-poppy-seed-recall.aspx">affected brands</a> in any form.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1000%2C666&q=45&auto=format&w=1000&fit=clip"><img alt="Bread rolls with poppy seeds on brown paper" src="https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1000%2C666&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/495557/original/file-20221116-13-p2a308.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">So far, there have been no poisonings reported after eating poppy seeds in bread or cake.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/kaiser-rolls-poppy-seeds-bakery-concept-1043931433">Shutterstock</a></span>
</figcaption>
</figure>
<h2>What if I have poppy seeds at home?</h2>
<p>The non-food grade poppy seeds we’re currently concerned about likely entered the food supply in the past two months. So, if you bought poppy seeds <a href="https://www.health.vic.gov.au/health-alerts/health-warning-on-poppy-seeds">before September 2022</a>, these are likely to be safe. </p>
<p>If you’ve bought poppy seeds in the past two months and these <a href="https://www.foodstandards.gov.au/industry/foodrecalls/recalls/Pages/default.aspx?k=poppy">are listed</a> as part of the national recall, you may be at risk.</p>
<p>You can throw them in the bin or return them to where you bought them for a refund.</p>
<h2>What if I’ve eaten poppy seeds or drunk the tea?</h2>
<p>If you or someone you know develops the following symptoms after consuming poppy seeds, seek urgent medical assistance by calling triple zero:</p>
<ul>
<li>severe muscle cramping, muscle spasms and abnormal movements </li>
<li>seizures </li>
<li>collapses or is unresponsive.</li>
</ul>
<p>If symptoms are mild, or you’re not sure if these are because of consuming poppy seeds, call the Poisons Information Centre for advice (details below).</p>
<p>If you’ve consumed poppy seeds more than four hours ago and you feel fine, you can be reassured. That’s because these poisoning symptoms typically happen quickly, within four hours. </p>
<p>If you’ve consumed a large number of poppy seeds as a drink, especially from an affected batch of seeds, in the past four hours, go to the emergency department regardless of symptoms.</p>
<hr>
<p><em>If this article raises health concerns for you or for someone you know about consuming poppy seeds, call the <a href="https://www.poisonsinfo.nsw.gov.au/">Poisons Information Centre</a> from anywhere in Australia on 131 126. This evidence-base advice is available 24 hours a day. For life-threatening symptoms, call 000.</em></p>
<hr>
<p><em>Update: the article has been updated to reflect prior poppy poisonings.</em></p><img src="https://counter.theconversation.com/content/194716/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Darren Roberts is the Medical Director of the NSW Poisons Information Centre and a clinical Toxicologist at Royal Prince Alfred Hospital, Sydney.
</span></em></p><p class="fine-print"><em><span>Jared Brown is a Senior Poisons Specialist in Toxicovigilance at NSW Poisons Information Centre.</span></em></p><p class="fine-print"><em><span>Katherine Isoardi is the Director of the Clinical Toxicology Unit, Princess Alexandra Hospital, Brisbane, and Medical Director of Queensland Poisons Information Centre, Queensland Children’s Hospital, Brisbane, Australia</span></em></p>Affected poppy seeds made into a tea have led to seizures and cardiac arrests.Darren Roberts, Conjoint Associate Professor in clinical pharmacology and toxicology, St Vincent’s Healthcare Clinical Campus, UNSW SydneyJared Brown, Clinical Associate Lecturer, School of Pharmacy, University of SydneyKatherine Isoardi, Conjoint Associate Professor, Faculty of Medicine, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.