By Nneka Nwogwugwu
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.
“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.
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.
The study shows that a fairly large set of pharmaceuticals exceed ‘safe levels’, and often at a very large number of sites.
Source: Eco watch