It’s SOS ‘underwater high’ in the rivers of different areas of the world, where they now swim trout ‘addicted’ to methamphetamine, European perch ‘high’ on antidepressant drugs who have lost their fear of predators, little fish who have developed anxiety as a result of taking caffeine at low concentrations, while others ‘fed’ with the synthetic estrogen used in contraceptive pills are experiencing sex reversals. Reason for these upheavals in the natural world? Fresh water is becoming less sweet for those who live there, and increasingly ‘drugged’, due to pharmaceutical pollution and illegal narcotics that end up in waterways and sewer systems and contaminate ecosystems. Addiction to medicines and drugs is no longer a problem only for humans, it goes beyond terrestrial borders and its effects can even be seen in the skies above cities: for example, female starlings, treated with antidepressants such as Prozac at concentrations found in wastewater become less attractive to potential mates, and male birds behave more aggressively and sing less to attract them than they do to those who have not taken doses of the drug.
The online ‘Guardian’ paints an overall picture of the growing threat to wildlife, citing several studies. The latest to raise the alarm are a group of scientists who, from the pages of ‘Nature Sustainability’, launch a loud appeal: “There is an urgent need to design ‘greener’, more ecological drugs, “which maintain effectiveness but also minimize the environmental impact”, because the contamination of ecosystems with active ingredients is becoming increasingly “pervasive”, write the authors of the intervention. Drug exposure is causing significant and unexpected changes in the behavior and anatomy of some animals. “We live in an increasingly medicalized world – observe the experts – Pharmaceutical products are indispensable in modern healthcare, having revolutionized the prevention and treatment of diseases, and will remain crucial in the future”.
However, the price to pay is “considerable”, they assure. “Discharges to the environment during the production, use and disposal of medicines are releasing mixtures of active pharmaceutical ingredients (APIs), as well as their metabolites, and additives, adjuvants, excipients and transformation products.” The extent of this pollution, the scientists continue, “was recently demonstrated in a large-scale geographic study that measured 61 different drugs in river water taken from 1,052 locations in 104 countries, across all continents. Approximately 43 % of these sampled sites had levels of at least one drug that exceeded those considered safe for ecological health. In addition, complex mixtures of many APIs (a maximum of 34), including a wide variety of drugs, were detected at the most contaminated sites. humans and veterinary”.
An example is the contraceptive pill which is leading to a numerical collapse and episodes of local extinction of some small fish, for example in a lake in Ontario, Canada. The work was conducted on the Pimephales promelas species and the focus is on high concentrations of estrogen and compounds that mimic its action. And the problem also affects humans. “Active pharmaceutical ingredients are found in waterways around the world, including in organisms we might eat,” warns Michael Bertram, a professor at the Swedish University of Agricultural Sciences. The issue of the impact on biodiversity, the message goes, deserves greater attention.
“There are a few routes through which these chemicals enter the environment,” continues Bertram, who is one of the authors of the study published in Nature Sustainability and is quoted by the Guardian. This happens for example “if the drugs released during production are treated inadequately – he lists – Another way is during use. In fact, when a human being takes a pill, not all of the drug is broken down in our body and therefore, through our excrement, residues are released directly into the environment.” Caffeine, anxiolytics, antidepressants, antipsychotics are all entering ecosystems, Bertram adds, as are illegal drugs, such as cocaine and methamphetamine.
To make clear the chain effect that all this can trigger, the scientist cites the example of the anti-inflammatory diclofenac which was administered to livestock in southern Asia and which caused a decrease in the vulture population in India by more than 97% between 1992 and 2007. The country also subsequently saw an increase in rabies cases caused by dogs feeding on livestock carcasses that were no longer eaten by birds. Another example is antibiotic pollution and the effect it has on microbes that become resistant. Hence the appeal to drug developers and manufacturers, scientists and politicians, “to recognize the growing environmental threat and urgently prioritize the sustainable design of greener medicines to prevent further environmental damage”. Greener drugs “reduce the potential for pollution throughout the entire cycle”, concludes Gorka Orive, University of the Basque Country and author of the study. “Drugs must be designed not only to be effective and safe, but also to have reduced potential risk to wildlife and human health when present in the environment.”
