Pharma pollutes ¼ of world’s rivers – study
A university report has shown that a quarter of the world’s rivers contain pharmaceuticals at potentially toxic levels.
Rivers in more than half of the world’s countries were sampled in one of the most comprehensive studies of its kind ever carried out.
Among some of the effects it found was a growing addiction to methamphetamines (speed) in fish and their feminisation, potentially affecting human populations, the study said.
UK University of York’s Global Monitoring of Pharmaceuticals Project looked at rivers on every continent and included 36 countries that had never been sampled before.
The only country sampled that did not contain any of the 61 pharmaceutical products targeted was Iceland.
At the other end of the scale, the Kai Tak River in Hong Kong was revealed to contain 34 of the 61 products.
“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,” said John Wilkinson, co-leader of the project which has been done within the department of environment and geography.
“Through our project, 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 that the entire scientific community was previously aware of: 36 new countries, to be precise, where only 75 had ever been studied before.”
Key findings included the most frequently detected pharmaceutical, Carbamazepine, which is used in the treatment of epilepsy and nerve pain, and was found in 62% of sample sites.
Other very common products found were antidepressants and sleeping pills, and potentially harmful ones included beta-blockers, antibiotics and antihistamines.
The most polluted sampling was from Bolivia, in the Rio Seke, which had a cumulative pharmaceutical concentration of 297 µg/litre. This is 115 times higher than that found in New York’s East River, the report said.
Concentrations of at least one pharmaceutical were above levels which may be toxic to algae, fish or daphnia (common water fleas) at a quarter of sampled sites.
The researchers also said that increasing such monitoring would provide data that could help develop strategies to limit the effects of such pollution.
