Pharmaceutical pollution is a global threat to the environment and living organisms, according to a two-year study
The first truly global-scale investigation of medicinal contamination in the environment has been carried out, led by York University. Previous research into active pharmaceutical ingredients (APIs) pollution has been patchy, focussing on a small number of geographical areas and contaminants, but the latest study monitored rivers in over half of the world – including 36 that had never previously been tested.
Worryingly, API pollution was found on every continent, and a quarter of sites found pollutants at potentially harmful levels.
Scientists sampled 258 rivers worldwide, including the Thames in London, testing for 61 pharmaceuticals. The most frequently detected were carbamazepine (an epilepsy and bipolar drug), metformin (a diabetes drug) and caffeine.
Contaminants with the highest concentrations found during the research were: paracetamol, caffeine, metformin, fexofenadine (anti histamine), sulfamethoxazole (antimicrobial), metronidazole (antimicrobial), and gabapentin (used to treat epilepsy).
APIs are released into the environment during manufacture and use, as well as disposal, and there is evidence that exposure can have negative effects on eco-systems and human health. There are concerns, for example, that the increased levels of antimicrobials in the environment could be aiding antimicrobial resistance (AMR) in microorganisms, adding to the AMR global health threat.
Scientists need to know the concentrations of APIs in river environments to ascertain the likely impacts.
"We’ve known for over two decades now that pharmaceuticals make their way into the aquatic environment where they may affect the biology of living organisms.”
Co-leader of the project, Dr John Wilkinson, from the University of York said: "With 127 collaborators across 86 institutions worldwide, the global monitoring of pharmaceuticals project is an excellent example of how the global scientific community can come together to tackle large-scale environmental issues.
"We’ve known for over two decades now that pharmaceuticals make their way into the aquatic environment where they may affect the biology of living organisms.
“But one of the largest problems we have faced in tackling this issue is that we have not been very representative when monitoring these contaminants, with almost all of the data focused on a select few areas in North America, Western Europe and China.
"Through our project, our knowledge of the global distribution of pharmaceuticals in the aquatic environment has now been considerably enhanced. This one study presents data from more countries around the world than the entire scientific community was previously aware of: 36 new countries to be precise where only 75 had ever been studied before.”
As well as posing a threat to human and environmental health, the findings threaten United Nations Sustainable Development Goals to improve water quality and reduce pollution.
Rubbish dumped along riverbanks, poor wastewater infrastructure and dumping of septic tanks into rivers, as well as pharmaceutical manufacturing were associated with high levels of API pollution. Those countries that have been previously unmonitored were found to be the most polluted, and include sub-saharan Africa, South America and parts of southern Asia.
The project will now look to expand to sample the environments around the river such as sediments, soils, and biota.
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