tag:theconversation.com,2011:/uk/topics/antibiotic-agent-4857/articlesAntibiotic agent – The Conversation2021-08-12T14:50:21Ztag:theconversation.com,2011:article/1650412021-08-12T14:50:21Z2021-08-12T14:50:21ZFungus in Nigeria’s industrial waste produces a promising antibiotic compound<figure><img src="https://images.theconversation.com/files/415499/original/file-20210810-23-kumlnb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Waste products from factories like this could hold the key to more novel antibiotic discoveries.
</span> <span class="attribution"><span class="source">Stefan Heunis/AFP via Getty Images</span></span></figcaption></figure><p><a href="https://doi.org/10.1111/j.1469-185X.1948.tb00567.x">Antibiotics</a> are life-saving drugs produced primarily by microorganisms which have been found in a variety of environments.</p>
<p>From <a href="https://dx.doi.org/10.11622%2Fsmedj.2015105">penicillin</a> discovered on mouldy old laboratory plates to <a href="https://doi.org/10.1111/j.1749-6632.2011.06354.x">tetracycline</a> from soil, these compounds revolutionised medicine. The antibiotic industry is now worth over <a href="https://www.grandviewresearch.com/industry-analysis/antibiotic-market">US$40 billion</a>.</p>
<p>Yet despite the importance of antibiotics, the size of drug companies and continuous research in developed countries, the <a href="https://doi.org/10.1128/AAC.01277-13">antibiotic pipeline</a> is almost empty. Few compounds that can be turned into drugs are being discovered, and pharmaceutical companies are more interested in improving known drugs. This means there aren’t new classes of antibiotics coming onto the market. And we need new ones because disease-causing bacteria continue to overcome most of the antibiotics in use globally. </p>
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Read more:
<a href="https://theconversation.com/the-world-needs-antibiotic-guardians-to-safeguard-their-future-use-127465">The world needs 'antibiotic guardians' to safeguard their future use</a>
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<p>Whether in hospitals or veterinary services, there are also <a href="https://www.downtoearth.org.in/news/health/antibiotic-resistance-nigeria-stares-at-a-major-catastrophe-68915">increasing cases</a> of drug resistance in Nigeria. </p>
<p>However, Nigeria’s contribution to antibiotic discovery from microscopic organisms is almost non-existent. One reason is that research of this nature takes a lot of time and money. A compound can be under consideration for a decade and end up failing the global standard. </p>
<p>Plant-based products (herbal mixtures and concoctions) can be formulated quickly and some get approval from the National Agency for Food and Drugs Administration and Control as marketable products. But drug products of microbial origin are uncommon.</p>
<p>The last time Nigeria reported a novel antimicrobial compound of microbial origin was in <a href="https://patents.google.com/patent/US5206263A/en?oq=US+Patent+5%2c206%2c263">1986</a>, under a project commissioned by Pfizer. The compound was used to treat coccidiosis in poultry and to promote growth in swine. It was the second such compound from Nigeria, but research stalled in the decades that followed.</p>
<p>While work continued on the potential of microorganisms as antibiotic producers, no novel compound was reported. The question became where to look next. Previous environmental clean-up <a href="https://iwaponline.com/aqua/article-abstract/63/1/66/28955/Biosorption-studies-for-the-removal-of-ferrous-ion?redirectedFrom=fulltext">research</a> suggested a way of filling the gap: using fungi found in waste produced by chemical industries.</p>
<h2>Industries as habitats for novel drug producers</h2>
<p>Sango-Ota, Ogun State’s industrial city, southwest Nigeria, is home to many industries, including producers of chemicals. In <a href="https://www.researchgate.net/publication/337909079_Potential_antibiotic-producing_fungal_strains_isolated_from_pharmaceutical_waste_sludge">our research</a>, we explored the waste (sludge) from these companies, looking for fungi with potential to produce antibiotics. We found six species that showed some promise. </p>
<p>The reason we targeted industrial sludge was that indiscriminate disposal of chemicals can alter the genes of organisms found in that habitat. It happens through long-term exposure, giving the organisms specialised properties. They might, for example, be able to produce new compounds.</p>
<p>Chemical wastes of selected companies stored in wells, tanks and other collection areas awaiting disposal into <a href="https://doi.org/10.1186/s43088-019-0026-8">the environment were sampled</a>. The sludge was collected from areas that have been undisturbed for a long time (bottom of wells, tanks and collection area). This approach was adopted to increase the chance of isolating fungi that possibly use the chemicals as food, and also produce substances that would help them survive at the expense of other intruding microorganisms. </p>
<p>We found that out of six fungi isolates, the organism <em>Geotrichum candidum</em> OMON-1 produced a novel compound that stops growth of and ultimately kills <em>Staphylococcus aureus</em>. This is a bacterium found on human skin which causes infections that are difficult to treat when they enter tissues. The compound also shows activity against other similar disease-causing pathogens found in food and water. </p>
<p>Working with India’s Institute of Microbial Technology, we purified the compound and identified it as carboxymethylcystyl-asparagyl-aspartate. It’s a peptide antibiotic with three amino acids in its sequence and has a low molecular weight compared to known antibiotics. It stopped growth of disease-causing pathogens after two hours.</p>
<h2>Need to explore similar environments</h2>
<p>Discovery of a new antibiotic compound from a Nigerian environment is good news for researchers in this field. The focus in recent years has been to look for <a href="https://doi.org/10.1016/j.jtusci.2017.01.006">novel microbial compounds</a> in the polluted Lagos lagoon. Now we see that strains of fungi, and indeed other organisms with modified properties, might also be found in other industrial wastes. It could lead to treatments for infections and other disease-related conditions or to other products of medical or industrial importance. </p>
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Read more:
<a href="https://theconversation.com/how-we-learnt-more-about-dangerous-pollutants-in-lagos-lagoon-139987">How we learnt more about dangerous pollutants in Lagos lagoon</a>
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<p>There are many industries in Nigeria that produce large volumes of waste which is poorly processed and disposed of. In Lagos State, chemical and pharmaceutical plants are the most polluting from over <a href="https://www.intechopen.com/chapters/16289">7,000 industries</a>, with less than 10% capacity to properly treat their waste. Plastic and textile manufacturing plants closely follow. </p>
<p>The next step could be to try to improve the compound we found. But instead we recommend exploring other modified or specialised environments for isolates with possible antibiotic action against some of the deadliest disease-causing bacteria. These include <em>Pseudomonas aeruginosa</em>, <em>Klebsiella pneumoniae</em>, <em>Acinetobacter baumannii</em>, <em>Neisseria meningitidis</em> and <em>Neisseria gonorrhoeae</em>.</p>
<p>It is a more important task because these bacteria are <a href="https://doi.org/10.3389/fmicb.2019.00539">tagged ESKAPE pathogens</a> and are priority organisms according to the World Health Organisation. They have reduced the effect of known antibiotics, or made them ineffective, through antimicrobial resistance. </p>
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Read more:
<a href="https://theconversation.com/drug-resistant-gonorrhoea-is-a-growing-threat-a-south-african-case-study-148012">Drug-resistant gonorrhoea is a growing threat: a South African case study</a>
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<p>Last hope antibiotics are <a href="https://doi.org/10.1016/j.cmi.2015.12.002">beginning to fail</a> in their treatment, keeping many people in hospital and leading to death of others. While the Lagos lagoon and other natural water bodies are vast and a tenacious search could uncover useful compounds there, modified industrial environments could be a faster road to the prize.</p><img src="https://counter.theconversation.com/content/165041/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sunday Omeike. PhD 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>Discovery of a new antibiotic compound from a Nigerian environment is good news for researchers in this field.Sunday Omeike. PhD, Lecturer in Industrial Microbiology (Antimicrobial compounds discovery and resistance research), McPherson UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/914122018-02-07T17:01:54Z2018-02-07T17:01:54ZAntibiotic resistance fight could get a little help from ants<figure><img src="https://images.theconversation.com/files/205318/original/file-20180207-74470-hweqft.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A giant ant carries a dead fellow in the name of cleanliness.</span> <span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Social_immunity#/media/File:Giant_Ant_(Camponotus_gigas)_carrying_a_dead_fellow_(15571767495).jpg">Dupont/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>The world is facing an <a href="https://theconversation.com/what-will-happen-when-antibiotics-stop-working-59938">antibiotics crisis</a>. Due to overuse, many once-powerful drugs are <a href="https://theconversation.com/is-the-antibiotic-apocalypse-nigh-51006">now useless</a> against certain strains of serious bacterial infections. So scientists are <a href="https://theconversation.com/new-class-of-antibiotics-discovered-and-why-there-may-be-more-to-come-36085">on the hunt</a> for new ways to attack harmful microbes.</p>
<p>One possibility is to investigate how other species have evolved ways to defend themselves. A <a href="http://rsos.royalsocietypublishing.org/lookup/doi/10.1098/rsos.171332">new study</a> highlights how most ants, even from small colonies, produce antimicrobial chemicals in their bodily secretions. It also suggests those ants that don’t make these substances are likely to have some other method of controlling bacteria that could be investigated. So perhaps the answer to antibiotic resistance is under our feet.</p>
<p>Like humans, the more than <a href="http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1001805">12,000 species</a> of ants are all highly social. This behaviour increases the chance that they come into to contact with germs. Comparable to our towns and cities, ant colonies take communal living to the next level, with up to tens of millions of individuals cohabiting in a single nest.</p>
<p>Colony survival depends on worker ants going out into the environment to collect food. Workers return to their densely inhabited nests loaded with food, but also harmful microbes. Returning workers then share their food and their germs through mouth-to-mouth feeding – essentially vomiting <a href="http://www.wired.co.uk/article/ants-throwing-up-hormones-development">into each other’s mouths</a>.</p>
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<p>If this wasn’t enough, the warm, moist conditions in ants’ nests make them ideal nurseries for disease-causing microbes. Finally, the members of almost all ants in a colony are related, so if one ant is susceptible to a germ, <a href="http://rspb.royalsocietypublishing.org/content/243/1306/55">it is likely that many others will be, too</a>.</p>
<p>Despite this longstanding threat of disease, ants are incredibly successful creatures. They dominate some environments and have diversified into thousands of species over <a href="https://phys.org/news/2006-04-ancient-ants-arose-million.html">150m years of evolution</a>. This suggests ants have found ways to deal with the high threat of disease. So what can we learn from them? </p>
<h2>How ants deal with disease</h2>
<p>Scientists have found that ants use a number of tricks to limit disease. Like humans, ants are exceptional cleaners. Many species have efficient waste-removal systems, ensuring diseased waste (including dead ants) is <a href="http://rspb.royalsocietypublishing.org/content/283/1831/20160625">removed from the nest or contained in special chambers</a>. They also regularly clean themselves and each other, and group together to <a href="http://rstb.royalsocietypublishing.org/content/370/1669/20140108">disinfect contaminated ants</a>.</p>
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<img alt="" src="https://images.theconversation.com/files/205319/original/file-20180207-74479-c26g2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/205319/original/file-20180207-74479-c26g2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=606&fit=crop&dpr=1 600w, https://images.theconversation.com/files/205319/original/file-20180207-74479-c26g2o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=606&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/205319/original/file-20180207-74479-c26g2o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=606&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/205319/original/file-20180207-74479-c26g2o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=761&fit=crop&dpr=1 754w, https://images.theconversation.com/files/205319/original/file-20180207-74479-c26g2o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=761&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/205319/original/file-20180207-74479-c26g2o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=761&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">You scratch my back…</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Social_Immunity#/media/File:Lasius_neglectus_grooming.jpg">Pull/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>But even with good hygiene habits, disease can still be an issue. Ants have evolved ways around this by using their own form of medicine. For example, some ants, when infected, eat toxins such as hydrogen peroxide <a href="http://onlinelibrary.wiley.com/doi/10.1111/evo.12752/abstract">to fight disease</a>. Others collect conifer resin, which they incorporate into their nests <a href="https://www.sciencedirect.com/science/article/pii/S0003347207005660">as a preventative measure</a>. Some species of ant are able to produce formic acid, which combines with the resin to form a <a href="http://onlinelibrary.wiley.com/doi/10.1002/ece3.2834/pdf">potent antimicrobial</a> agent.</p>
<p>We also know that ants also produce their own antimicrobials <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2672.1992.tb01822.x/abstract;jsessionid=937BED2D39EA0DCAA544A751A052043C.f04t03">in bodily secretions</a>. Now researchers have tried to work out what affects how these chemicals are made. In a new study published in the journal <a href="http://rsos.royalsocietypublishing.org/lookup/doi/10.1098/rsos.171332">Royal Society Open Science</a>, researchers from Arizona State University investigated the antimicrobial activity of 20 ant species in the US living in nests with between 80 and 220,000 inhabitants.</p>
<p>The researchers predicted that larger nest species would produce more effective antimicrobials, because of a greater risk of coming into contact with disease. Testing external secretions against <em>Staphylococcus epidermidis</em>, a common bacterium not known to cause disease, showed that 60% of the ant species produced secretions with antimicrobial activity. But, surprisingly, 40% didn’t produce an antimicrobial that could kill the bacterium.</p>
<p>What’s more, species in larger colonies were no more likely to have antimicrobial activity than small colonies. This is surprising as it is generally thought that disease is more likely to be spread in larger colonies. The authors suggest that the 40% of ants without antimicrobial activity have other methods of controlling the spread of bacteria. But we also don’t know if these 40% produce antimicrobial agents that work against other microbes.</p>
<h2>Antibiotics for the future?</h2>
<p>This adds to the idea that ants could well be a good source of new antibiotics. Not only do ants produce their own antimicrobial agents, but they can also encourage other beneficial microbes to grow. For example, researchers recently discovered a bacterium living among one ant species that produces compounds capable of killing harmful bacteria <a href="http://pubs.rsc.org/en/content/articlepdf/2014/SC/C6SC04265A?page=search">resistant to conventional antibiotics</a>, including the common superbug MRSA.</p>
<p>Millions of years of evolution in a high-risk environment have made ants a potential source of vital antimicrobials. These substances still need to be turned into effective drugs and then trialled in humans. But the more we learn about the strategies ants use to fight disease, the more likely we are to uncover new ways to deal with the threat of resistant bacteria and disease.</p><img src="https://counter.theconversation.com/content/91412/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rob Hammond receives funding from NERC and BBSRC.</span></em></p><p class="fine-print"><em><span>Charlie Durant 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>Ants produce their own antimicrobial chemicals to fight bacteria.Charlie Durant, PhD Candidate, Department of Genetics and Genome Biology, University of LeicesterRob Hammond, Lecturer, Department of Genetics and Genome Biology, University of LeicesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/533762016-01-29T10:47:02Z2016-01-29T10:47:02ZIn a world with no antibiotics, how did doctors treat infections?<figure><img src="https://images.theconversation.com/files/108638/original/image-20160119-29762-nzi6kn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Bloodletting was treatment for infection in the past. </span> <span class="attribution"><span class="source">Wellcome Library, London</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>The development of antibiotics and other antimicrobial therapies is arguably the greatest achievement of modern medicine. However, overuse and misuse of antimicrobial therapy predictably leads to resistance in microorganisms. Antibiotic-resistant bacteria such as methicillin-resistant <em>Staphylococcus aureus</em> (MRSA), vancomycin-resistant <em>Enterococcus species</em> (VRE) and carbapenem-resistant <em>Enterobacteriaceae</em> (CRE) have emerged. Certain CRE species are resistant to multiple antibiotics, and have been deemed “<a href="http://www.dailyherald.com/article/20160123/entlife/160129570/">superbugs</a>” in the news.</p>
<p>Alternative therapies have been used to treat infections since antiquity, but none are as reliably safe and effective as <a href="http://dx.doi.org/10.3389/fmicb.2010.00134">modern antimicrobial therapy</a>. </p>
<p>Unfortunately, due to increasing resistance and lack of development of new agents, the possibility of a return to the pre-antimicrobial era may become a reality. </p>
<p>So how were infections treated before antimicrobials were developed in the early 20th century? </p>
<h2>Blood, leeches and knives</h2>
<p>Bloodletting was used as a medical therapy for over 3,000 years. It originated in Egypt in <a href="http://www.bcmj.org/premise/history-bloodletting">1000 B.C.</a> and was used until the middle of the 20th century.</p>
<p>Medical texts from antiquity all the way up until 1940s recommend bloodletting for a wide variety of conditions, but particularly for infections. As late as 1942, William Osler’s 14th edition of <a href="https://archive.org/details/principlesandpr00mccrgoog">Principles and Practice of Medicine</a>, historically the preeminent textbook of internal medicine, <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3124909/">included bloodletting as a treatment</a> for pneumonia. </p>
<p>Bloodletting is based on <a href="http://dx.doi.org/10.4997/JRCPE.2014.117">an ancient medical theory</a> that the four bodily fluids, or “humors” (blood, phlegm, black bile and yellow bile), must remain in balance to preserve health. Infections were thought to be caused by an excess of blood, so blood was removed from the afflicted patient. One method was to make an incision in a vein or artery, but it was not the only one. Cupping was another common method, in which heated glass cups were placed on the skin, creating a vacuum, breaking small blood vessels and resulting in large areas of bleeding under the skin. Most infamously, leeches were also used as a variant of bloodletting.</p>
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<span class="caption">A man sitting in chair, arms outstretched, streams of blood pouring out as a nun places leeches on his body.</span>
<span class="attribution"><span class="source">Images from the History of Medicine (NLM)</span></span>
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<p>Interestingly, though bloodletting was recommended by physicians, the practice was actually performed by barbers, or “barber-surgeons.” The red and white striped pole of the barbershop originated as “advertising” their bloodletting services, the red symbolizing blood and the white symbolizing bandages.</p>
<p>There may actually have been some benefit to the practice – at least for certain kinds of bacteria in the early stages of infection. Many bacteria require iron to replicate, and iron is carried on heme, a component of the red blood cell. In theory, fewer red blood cells resulted in less available iron to sustain the bacterial infection.</p>
<h2>Some mercury for your syphilis?</h2>
<p>Naturally occurring chemical elements and chemical compounds have historically have been used as therapies for a variety of infections, particularly for wound infections and syphilis.</p>
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<a href="https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=976&fit=crop&dpr=1 600w, https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=976&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=976&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1227&fit=crop&dpr=1 754w, https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1227&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/108634/original/image-20160119-29754-1tixp5j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1227&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A woodcut from 1689 showing various methods of syphilis treatment including mercury fumigation.</span>
<span class="attribution"><a class="source" href="http://ihm.nlm.nih.gov/luna/servlet/view/search?q=A013510">Images from the History of Medicine (NLM)</a></span>
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<p>Topical iodine, bromine and mercury-containing compounds were used to treat infected wounds and gangrene during the American Civil War. <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2706344/">Bromine was used most frequently</a>, but was very painful when applied topically or injected into a wound, and could cause tissue damage itself. These treatments inhibited bacterial cell replication, but they could also harm normal human cells.</p>
<p>Mercury compounds were used to <a href="http://jmvh.org/article/syphilis-its-early-history-and-treatment-until-penicillin-and-the-debate-on-its-origins/">treat syphilis</a> from about 1363 to 1910. The compounds could be applied to skin, taken orally or injected. But the side effects could include extensive damage to skin and mucous membranes, kidney and brain damage, and even death. <a href="http://www.nejm.org/doi/full/10.1056/NEJMp110534">Arsphenamine</a>, an arsenic derivative, was also used in the first half of the 20th century. Though it was effective, side effects included optic neuritis, seizures, fever, kidney injury and rash.</p>
<p>Thankfully, in 1943, penicillin supplanted these treatments and remains the first-line therapy for all stages of syphilis. </p>
<h2>Looking in the garden</h2>
<p>Over the centuries, a variety of herbal remedies evolved for the treatment of infections, but very few have been evaluated by controlled clinical trials. </p>
<p>One of the more famous herbally derived therapies is quinine, which was used to treat malaria. It was originally isolated from the bark of the cinchona tree, which is native to South America. Today we use a synthetic form of quinine to treat the disease. Before that, cinchona bark was dried, ground into powder, and mixed with water for people to drink. The use of cinchona bark to treat fevers was described by Jesuit missionaries in the 1600s, though it was likely used in native populations much earlier.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=917&fit=crop&dpr=1 600w, https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=917&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=917&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1152&fit=crop&dpr=1 754w, https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1152&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/108643/original/image-20160119-29750-1h9cctc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1152&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 engraving of a Quinine plant, 1880.</span>
<span class="attribution"><span class="source">Wellcome Library, London</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Artemisinin, which was synthesized from the <em>Artemisia annua</em> (sweet wormwood) plant is another effective malaria treatment. A Chinese scientist, <a href="https://theconversation.com/the-secret-maoist-chinese-operation-that-conquered-malaria-and-won-a-nobel-48644">Dr. Tu Youyou</a>, and her team analyzed ancient Chinese medical texts and folk remedies, identifying extracts from <em>Artemisia annua</em> as effectively inhibiting the replication of the malaria parasite in animals. Tu Youyou was coawarded the 2015 Nobel Prize in Physiology or Medicine for the discovery of artemisinin.</p>
<p>You probably have botantically derived therapy against wound infection in your kitchen cupboard. The use of honey in wound healing dates back to the <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3609166/">Sumerians in 2000 B.C.</a>. The high sugar content can dehydrate bacterial cells, while acidity can inhibit growth and division of many bacteria. Honey also has an enzyme, glucose oxidase, that reduces oxygen to hydrogen peroxide, which kills bacteria.</p>
<p>The most potent naturally occurring honey is thought to be <a href="http://www.webmd.com/a-to-z-guides/manuka-honey-medicinal-uses">Manuka honey</a>. It is derived from the flower of the tea tree bush, which has additional antibacterial properties.</p>
<p>Like other botanically derived therapies, honey has inspired the creation of pharmaceuticals. MEDIHONEY®, a <a href="http://www.dermasciences.com/medihoney">medical grade product</a> developed by Derma Sciences, is used to promote healing in burns as well as other types of wounds.</p>
<h2>Combating antimicrobial resistance</h2>
<p>While some of these ancient therapies proved effective enough that they are still used in some form today, on the whole they just aren’t as good modern antimicrobials at treating infections. Sadly, thanks to overuse and misuse, antibiotics are becoming less effective.</p>
<p>Each year in the United States, at least <a href="http://www.cdc.gov/drugresistance/">two million people</a> become infected with bacteria that are resistant to antibiotics, and at least 23,000 people die each year as a direct result of these infections.</p>
<p>While resistant bacteria are most commonly reported, resistance also can arise in other microorganisms, including fungi, viruses and parasites. Increasing resistance has raised the possibility that certain infections may eventually be untreatable with the antimicrobials we currently have.</p>
<p>The race is on to find new treatments for these infections, and researchers are exploring new therapies and new sources for antibiotics. </p>
<p>Besides <a href="http://www.cdc.gov/drugresistance/protecting_yourself_family.html">using antibiotics as directed and only when necessary,</a> you can avoid infections in the first place with appropriate immunization, safe food-handling practices and washing your hands. </p>
<p>Tracking resistant infections so we can learn more about them and their risk factors, as well as limiting the use of antibiotics in humans and animals, could also help curb the risk of resistant bacteria.</p><img src="https://counter.theconversation.com/content/53376/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cristie Columbus 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>While some ancient therapies proved effective enough that they are still used in some form today, on the whole they just aren’t as good as modern antimicrobials at treating infections.Cristie Columbus, Vice Dean, Texas A&M College of Medicine, Texas A&M UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/397192015-04-09T11:50:31Z2015-04-09T11:50:31ZWhy I wasn’t excited about the medieval remedy that works against MRSA<figure><img src="https://images.theconversation.com/files/77352/original/image-20150408-18075-e93l6g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Good thing we don't have superbugs in hospital yet.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/snake3yes/272408110/in/photolist-q5ary-dW2vkW-9v2jPx-5Pjz2N-9v2iDv-4utkg-5Dwti-8trAJL-dVVWuR-7jN551-7H3T7J-dW2xif-86aVWg-7GYXuT-6dWHxr-6nyemC-6YX9k9-btZ9sD-aDiZqV-5ePAf-nx1FV-pYep3-6dWJei-73rsf8-nx1BW-GSHYb-63TyTJ-5Vz8q9-6ZdY7c-63Pmnz-73VAdn-nx1Ar-aoX6na-6SHgpF-aoX2yc-cBi52-4EWozt-6GM723-7TJ4pX-cBhYY-kQguYg-5CHPb7-8toyan-cjm5Co-7UFQkx-4MpuAE-7xfd25-7zUBwp-8HFEzw-qgLH6">Snake3yes</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>It’s not often that medievalists get as excited as they have been over <a href="http://www.newscientist.com/article/dn27263-anglo-saxon-remedy-kills-hospital-superbug-mrsa.html">the revival of a medieval remedy</a> for eye conditions involving garlic, onions, wine and ox gall, prepared in a bronze vessel. The concoction, mixed up by a team from Nottingham University, appeared to <a href="http://bit.ly/1NzG1jo">show promising results</a> in the battle against MRSA. It didn’t kill it all, but it apparently killed 90%. This has revived enthusiasm for trawling ancient texts for the solutions to modern problems. </p>
<p>The remedy comes from <a href="http://britishlibrary.typepad.co.uk/science/2015/04/a-medieval-medical-marvel.html">Bald’s Leechbook</a>, a 10th-century manuscript, and the powers of the separate ingredients of the remedy have been known for some time: <a href="http://www.ncbi.nlm.nih.gov/pubmed/10594976">garlic</a> has anti-fungal, anti-viral, anti-parasitic and anti-microbial qualities. </p>
<p>The idea of subjecting medieval recipes to modern methods of testing is also not new. In 1993, in his book Anglo-Saxon Medicine, the biologist ML Cameron singled out this very remedy as “an outstanding example of a remedy likely to have been helpful”. And it was this same remedy that was reconstructed by a team from Wheaton College, although their results, published in 2005, found that it had no effect. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/77353/original/image-20150408-18063-pkwysn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/77353/original/image-20150408-18063-pkwysn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/77353/original/image-20150408-18063-pkwysn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/77353/original/image-20150408-18063-pkwysn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/77353/original/image-20150408-18063-pkwysn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/77353/original/image-20150408-18063-pkwysn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/77353/original/image-20150408-18063-pkwysn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">But beware the garlic breath.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/mdid/199386734/in/photolist-iBUJj-pUAibC-8j2EkN-wV2LV-ciDorC-3Fe6Q-6NJDv8-8KwHZn-6KGh1d-7t29ma-ozFaJ-Eiqk-nULCok-cEoZK1-4BDRwv-yAC9f-pNtje6-4pK1yV-74z9Wx-3tquqZ-4zXoaU-9mx7Cq-JoyTL-c26HwA-89JsHY-7zPS15-9aHh7R-7i7hVQ-59D9kR-aaWjRa-rBmFRo-dgM72Y-7PnLms-foEyJ8-onWue-8kb2Lf-dNamZ7-5KTVj5-64f4bm-5uVFUB-8p1Hxy-c9pSQG-7AEXDP-dhecMr-ZHTr-f3KfEN-oW4vNC-foFEUy-bytCeJ-caH4ys">David Pursehouse</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p><a href="http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=430414&fileId=S0263675105000086">They concluded</a> that “some of the Anglo-Saxon recipes take biologically efficacious ingredients and process them into ineffective mixtures”. So while the garlic would work on its own, the compound remedy prepared over nine days, wouldn’t.</p>
<p>The 2005 research was part of a rehabilitation of the Anglo-Saxons, which aimed to show they were considerably more learned and deserving of more respect than had previously been thought. But, for the Wheaton College team, the remedies did nothing to support that view. </p>
<h2>The problem with revival</h2>
<p>There are also some serious problems with the new, more positive, claims for the eye salve. And these apply to all such attempts to rediscover ancient remedies.</p>
<p>First, can we really identify the ingredients? For the eye remedy for example, the Anglo Saxon word <a href="http://oldenglish-plantnames.org/index">“cropleek”</a> found in the ingredients can mean leek, garlic or shallot, or perhaps a specific part of a leek. Websites that have attempted to translate the remedy have also listed onions. So what plant should a modern researcher select for their trials? And do modern plant descendants have the same properties now as their ancestors did?</p>
<p>Second, in compound recipes, how do we know which ingredients are worth testing? <a href="http://britishlibrary.typepad.co.uk/digitisedmanuscripts/2013/10/anglo-saxon-medicine.html">Descriptions of 10th-century medicine</a> sometimes suggest that we can easily decide which ingredients are “improbable” and which are “feasible”. An example seen as combining the two is a remedy for a burn including “silver filings, bear’s grease, thyme, rose petals and verbena”. </p>
<p>From a modern perspective, bear’s grease is unlikely to differ from other animal fats or have any health benefits beyond acting as a lubricant or protective barrier.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=833&fit=crop&dpr=1 600w, https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=833&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=833&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1047&fit=crop&dpr=1 754w, https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1047&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/77349/original/image-20150408-18053-mlcqji.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1047&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A page from Bald’s Leechbook.</span>
</figcaption>
</figure>
<p>Third, what’s the medical problem that the remedy in the Leechbook is designed to treat? One announcement of the discovery suggests that the <a href="http://www.medievalists.net/2015/03/30/anglo-saxon-medicine-is-able-to-kill-modern-day-superbug-researchers-find/">many conditions</a> it could treat are “clearly bacterial infections (weeping wounds/sores, eye and throat infections, skin conditions such as erysipelas, leprosy and chest infections)”. But is that really “clear”? We could decide that if pus is mentioned, then there must be an infection. </p>
<p>But even here we need to be sensitive to different beliefs about the body. The history of medicine includes the concept of “laudable pus” – pus which is a good thing, a stage of healing rather than a complication. This idea was still <a href="http://www.bmj.com/content/2/2904/286">around in 1916</a> but there was always debate over this – <a href="https://books.google.co.uk/books?id=yq2W6dwJa5gC&pg=PA39&dq=laudable+pus&hl=en&sa=X&ei=fSUcVYTbMsj3UNe3hLAJ&ved=0CCoQ6AEwAw#v=onepage&q=laudable%20pus&f=false">even in the Middle Ages</a>. </p>
<p>Some scholars interpret the condition for which the eye salve is used as being a stye, but a stye is normally self-limiting and so goes away regardless of what is put on it.</p>
<h2>Flying venom, hidden nightgoers</h2>
<p>In many cases we can’t really match a modern diagnosis to an ancient one. Bald’s Leechbook also offers us “a salve against elf-kind and nightgoers, and the people with whom the devil has intercourse”. Or what about the <a href="http://www.indiana.edu/%7Epsource/PDF/Archive%20Articles/Spring2012/2012%20-%20Spring%20-%207%20-%20Kinney,%20Shirley.pdf">Anglo-Saxon condition called “flying venom”</a>?</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/77350/original/image-20150408-18086-jbj8q1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/77350/original/image-20150408-18086-jbj8q1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=736&fit=crop&dpr=1 600w, https://images.theconversation.com/files/77350/original/image-20150408-18086-jbj8q1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=736&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/77350/original/image-20150408-18086-jbj8q1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=736&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/77350/original/image-20150408-18086-jbj8q1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=925&fit=crop&dpr=1 754w, https://images.theconversation.com/files/77350/original/image-20150408-18086-jbj8q1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=925&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/77350/original/image-20150408-18086-jbj8q1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=925&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">All sorts.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/30591976@N05/3966528842/in/photolist-73vuQj-5CDvTn-pFa5jG-6dWHxr-kQguYg-6NxtbW-dSmaGn-dLHXSX-bviyq7-7H3MMd-n8rsde-6gZwn5-5CHPb7-73rsf8-biUsFg-98JNDg-fm1p1K-7Ru3dG-6M543v-6XWdi6-e4Cejx-87jpFR-dmCqu5-6XWeMc-prayAM-ao4AEU-ek8Wag-e4CkJa-e4HWu1-e4HZ6U-qgLHx-e4HQdY-q5aVd-7Ru3e7-6M99t5-94ivvg-aph6z7-4utb1-bu2EXc-btZb3v-bux3SZ-nx1y6-4EWozt-e4HNjs-e4HVWj-cjm5Co-e4Cctc-e4HPtJ-e4Ceti-prcoUG">Paul Walker from Cyril Bunt, 1955.</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>In the ancient Greek medical tradition, the wandering womb was a condition. If we analyse remedies for the wandering womb in terms of their ingredients, what do we get? Puppies stuffed with aromatics feature in <a href="https://theconversation.com/floating-wombs-and-fumigation-why-gwyneth-paltrow-has-steam-douching-all-wrong-37006">fumigations</a>. Garlic was also used. If we study the chemical constituents of ancient remedies and if one ingredient turns out to be antibacterial, then does that mean we have to conclude that the wandering womb was an infection? But if we decide that, then what do we do about those puppies?</p>
<h2>Ancient medicine to the rescue?</h2>
<p>So I remain a sceptic here, especially when the announcement of the remedy remade came at the same time as a crowd-sourcing appeal for a tiny sum to pay for an undergraduate student to help out in the lab. </p>
<p>Even more importantly, we see a mixture of arts and science academics <a href="http://www.nottingham.ac.uk/news/pressreleases/2015/march/ancientbiotics---a-medieval-remedy-for-modern-day-superbugs.aspx">on the video</a>. Teamwork is certainly important. As is the very real <a href="http://www.theguardian.com/education/2015/mar/29/war-against-humanities-at-britains-universities">threat to humanities</a> subjects in the face of science, technology, engineering, and mathematics (STEM) funding. </p>
<p>Maybe that’s why so many in the arts and humanities seem to be enthusiastic about the eye disease remedy. But while it’s interesting that ancient remedies can be put together, ultimately there’s a danger that we simply replace the view that the only medicine worth knowing about is what we have today, with a misguided idea that the past holds all the answers.</p><img src="https://counter.theconversation.com/content/39719/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Helen King has received funding from the Wellcome Trust</span></em></p>Reviving old remedies doesn’t tell us anything we don’t already know.Helen King, Professor of Classical Studies, The Open UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/141042013-05-15T23:19:07Z2013-05-15T23:19:07ZPopping pills can harm wildlife via a trip to the loo<figure><img src="https://images.theconversation.com/files/23543/original/3y4jf9vb-1368359758.jpg?ixlib=rb-1.1.0&rect=0%2C5%2C3504%2C2329&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Medicine residues that we flush down the toilet can affect fish and other wildlife.</span> <span class="attribution"><span class="source">Chris Ison/PA</span></span></figcaption></figure><p>It’s not a thought that occurs to most of us, but flushing the toilet doesn’t just mean disposing of our bodily waste. We’re also flushing away some of the medicine we take down with it. Our contraceptive pills, analgesics, antidepressants, blood thinners and beta blockers all have a life in our nation’s waterways once their work on ourselves is done. And for decades, scientists have been expressing concern over how the chemicals we excrete in this way affect the environment.</p>
<p>The good news is that concentrations of chemicals in the water are not thought to be a concern for human health. You would need to drink hundreds of litres of surface water to take in as much as a single daily dose of any medication. The bad news is that the same cannot be said for wildlife. </p>
<p>In Washington’s Potomac River, male fish have <a href="http://www.guardian.co.uk/environment/2010/apr/21/toxic-stew-chemicals-fish-eggs;">exhibited female traits</a> as a result of hormones being flushed into the water and <a href="http://www.nytimes.com/2013/02/15/science/traces-of-anxiety-drug-may-affect-fish-behavior-study-shows.html?_r=0">fish behaviour changes</a> have been ascribed to persistent antidepressants in wastewater. </p>
<p>Another case of medicines harming animals occurred when <a href="http://www.ouramazingplanet.com/391-new-test-may-aid-critically-endangered-vultures.html">the vulture population in India crashed</a> due to poisoning with Diclofenac, a drug administered to the cattle they ate. But Diclofenac flushed down the toilet by humans is also of concern. Along with two contraceptive hormones, the anti-inflammatory drug is now included on <a href="http://www.ewaonline.de/portale/ewa/ewa.nsf/home?readform&objectid=04FE8F58EAB20312C12579B300570506">an EU watch list</a> of substances which will be monitored to assess the risk they present to the aquatic environment.</p>
<p>Disposal of unwanted medicines down the drain may also be a factor, as in most countries only a few people take leftover drugs back to the pharmacy. But the majority of pharmaceutical pollution in Europe does happen via human excretion. And given the fact we excrete about 70% of the medicine we take (<a href="http://www.sciencedaily.com/releases/2010/12/101207112402.htm">up to 90% in the case of antibiotics</a>), you’d assume we could just take less of it. </p>
<p>But for most medicines to be effective, it is necessary to maintain a certain concentration of the drug in your blood plasma. And as the kidneys continually filter the blood, the drug is gradually removed and excreted via urine into the sewer and it is necessary to keep topping up the drug to maintain the right concentration. </p>
<p>Our consumption of certain drugs is going up steadily, and in the case of some drug groups, <a href="http://www.guardian.co.uk/society/2011/dec/30/antidepressant-use-england-soars">such as antidepressants</a>, quite dramatically.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/23856/original/hcms4qpv-1368614098.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/23856/original/hcms4qpv-1368614098.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=372&fit=crop&dpr=1 600w, https://images.theconversation.com/files/23856/original/hcms4qpv-1368614098.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=372&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/23856/original/hcms4qpv-1368614098.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=372&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/23856/original/hcms4qpv-1368614098.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=467&fit=crop&dpr=1 754w, https://images.theconversation.com/files/23856/original/hcms4qpv-1368614098.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=467&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/23856/original/hcms4qpv-1368614098.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=467&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">Fish can be especially susceptible to drug residues.</span>
<span class="attribution"><span class="source">Chris Ison/PA</span></span>
</figcaption>
</figure>
<p>Most drugs are only partially removed by conventional wastewater treatment works and so enter the aquatic environment. In some rivers, treated effluent from multiple treatment works can make up more than half of the total flow, so persistent chemicals can accumulate.</p>
<p>How bad are these substances for the environment? One problem is that it’s almost impossible to measure. For a start, there are about 3000 different drugs licensed in Europe, some very toxic, others harmless. These drugs reach the environment in an endless variety of cocktails, some of which may be much more harmful than others.</p>
<p>Some species are also more sensitive than others. Many effects that don’t actually kill the wildlife are not well understood. Sometimes physical changes might be seen - for example fish embryos having kinked tails instead of straight ones. How exactly this affects the fish population, and perhaps more importantly, their function in an ecosystem, is not clear. </p>
<p>Environmental changes can occur quite suddenly when changes have gone too far for the system to work. When the contraceptive hormone EE2 reached levels of five parts per trillion in <a href="http://www.pnas.org/content/104/21/8897">Canadian lakes</a>, one fish species population crashed. With thousands of drugs, infinite combinations and hundreds of thousands of aquatic species, an exact figure on safe levels can’t be given.</p>
<p>However, the benefits that medicines bring, and particularly prescribed medicines, are undisputed and no-one wants to go back to a time where they weren’t available. </p>
<p>It is possible to stop residues reaching the environment by advanced sewage treatment technologies that are capable of removing the pollutants: advanced oxidation <a href="http://www.sciencedirect.com/science/article/pii/S0043135402005705">techniques using UV or ozonation</a>, for example, or filtering the water through activated carbon. But these measures are expensive and energy intensive. Site-specific water treatment, in hospitals for example, could be used to clean water before it enters the main drain, but on average only about 20% of all drugs are taken in hospitals. </p>
<p>But we need to do more. A first step is to raise awareness of medicines’ environmental effects. We are currently investigating whether people - including doctors - could change how they consume, prescribe and dispose of medicines. </p>
<p>It could be worth looking at our buying habits of non-essential drugs and balancing consideration of the environment as well as therapeutic benefit and cost, when deciding what medicines to buy or prescribe. </p>
<p>It might even be that patients taking the most toxic medication may be asked how they would feel about using devices catching their urine so it can be disposed of safely. </p>
<p>Ultimately, society needs to decide whether we want to pay extra for advanced sewage treatment, whether we are prepared to change our pharmaceutical consumption or use “green pharmacy” products from the pharmaceutical industry - or a combination of all of these.</p><img src="https://counter.theconversation.com/content/14104/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The noPILLS project, on which Karin Helwig is a researcher, receives funding from Interreg IV-B North-West Europe. </span></em></p>It’s not a thought that occurs to most of us, but flushing the toilet doesn’t just mean disposing of our bodily waste. We’re also flushing away some of the medicine we take down with it. Our contraceptive…Karin Helwig, Researcher, Glasgow Caledonian UniversityLicensed as Creative Commons – attribution, no derivatives.