Pharmaceutical Drug Pollution in Rivers Poses ‘Global Threat to Human and Environmental Health,’ Study Finds
Pharmaceutical drugs have polluted the world’s rivers and pose “a global threat to environmental and human health,” according to a new study by the University of York. The most extensive global study to date found that among the most polluted rivers were those in Bolivia, Pakistan and Ethiopia, while rivers in the Amazon rainforest, Iceland and Norway were those with the least amounts of drug pollution, BBC News reported.
The study, “Pharmaceutical pollution of the world’s rivers,” in which 127 researchers representing 86 institutions participated, was published by the journal Proceedings of the National Academy of Sciences.
“Typically, what happens is, we take these chemicals, they have some desired effects on us and then they leave our bodies,” research leader Dr. John Wilkinson said to BBC News.
“What we know now is that even the most modern efficient wastewater treatment plants aren’t completely capable of degrading these compounds before they end up in rivers or lakes,” Wilkinson said.
It is known that biologically active compounds produced by humans cause harm to wildlife, including the feminization of fish, and the presence of antibiotics in the environment increases the risk of drug resistance.
The researchers took measurements at more than 1,000 sites for concentrations of “active pharmaceutical ingredients (APIs),” The Guardian reported. The survey covered all continents, sampling 258 rivers in 104 countries.
More than a quarter of the rivers tested had API levels that were regarded as “unsafe for aquatic organisms,” reported BBC News.
Although 2,500 APIs are in use, only 50 to 100 drugs were able to be analyzed in a single sample, so the researchers tested those that are most common, reported The Guardian.
Among the top ten percent of locations that had the greatest cumulative drug concentrations was Madrid, Spain, while Dallas, Texas, and Glasgow in the UK landed in the top 20 percent.
Only Iceland and a village in Venezuela inhabited by Indigenous people who don’t use any modern medicines had no detected levels, as reported by The Guardian.
The most common APIs found in the rivers were metformin, a diabetes medication, carbamazepine, used to treat nerve pain and epilepsy, and caffeine. One in five of the sites sampled had dangerous levels of antibiotics.
“The World Health Organization and UN and other organisations say antimicrobial resistance is the single greatest threat to humanity — it’s a next pandemic,” said Wilkinson, as The Guardian reported. “In 19% of all of the sites we monitored, the concentrations of [antibiotics] exceeded the levels that we’d expect to encourage bacteria to develop resistance.”
Nicotine and acetaminophen were also found in high concentrations in the rivers sampled. Artemisinin, used to treat malaria, was found in high concentrations in Africa, BBC News reported.
“Ecological risks could well be greater than predicted for the single APIs due to toxicological interactions of these mixtures,” said the researchers, as reported by The Guardian.
It is estimated that antibiotic resistance to bacterial infections killed five million people in 2019, according to research published last month, with the regions most affected closely matching those with the most APIs.
“If I were a fish living in some of these rivers, I’d be worried right now,” Wilkinson said, as The Guardian reported. Wilkinson said that humans swimming in most rivers wouldn’t result in high doses of the drugs because the levels weren’t great enough.
Nearly all previous assessments had been conducted in North America and Europe, but the work in this study includes measurements from 36 countries — with those in South America and Africa especially represented — that were sampled for the first time.
Countries with low-to-middle incomes like Nigeria and India had the highest API concentrations, which researchers believe may be attributable to the population in those countries being able to afford pharmaceutical drugs, but not having good enough sewage systems to mitigate them.
“We know good sewage connectivity and wastewater treatment is the key to minimising, though not necessarily eliminating, pharmaceutical concentrations,” Wilkinson said, as reported by The Guardian. “However, that is extremely expensive as there’s a lot of infrastructure involved.”
Other sites that were most affected by pharmaceutical pollution were those that lacked decent wastewater management, areas where sewage was dumped and locations where pharmaceuticals were manufactured.
“We have seen contaminated rivers in Nigeria and in South Africa with very high concentrations of pharmaceuticals and this is basically down to the lack of infrastructure in wastewater treatment,” said associate professor of emerging contaminants at Birmingham University in the UK. Dr. Mohamed Abdallah, reported BBC News.
“This is most concerning because you have the most vulnerable populations with the least access to healthcare exposed to this,” Abdallah said.
Wilkinson said that one way to reduce drug pollution in rivers is to be more careful in the use of medicines, especially antibiotics, The Guardian reported.
“Pharmaceuticals are almost omnipresent in rivers across the world,” said University of Gothenburg, Sweden, professor Joakim Larsson, who was not one of the study’s researchers, as reported by The Guardian.
“The study shows that a fairly large set of pharmaceuticals exceed ‘safe levels’, and often at a very large number of sites. Bacteria do not respect national borders, so if a new resistant bacterium develops on one side of our planet, it soon becomes a risk for everyone,” Larsson said.