Pharmaceutical drugs that end up in the world's waterways after being excreted, flushed and treated at wastewater treatment plants may lead to unexpected ecological impacts, according to a new study of wild European perch. Tomas Brodin and colleagues from Ume University in Sweden discovered that the fish ate faster, became bolder and acted less social after being subjected to an anxiety-moderating drug, known as Oxazepam.
The psychiatric drug is used to treat anxiety in humans. But, Oxazepam residues often wind up in natural aquatic systems, downstream from sewage treatment plants, where their effects on ecosystems have been unknown. Now, Brodin and the other researchers have dosed wild perch with amounts of Oxazepam equivalent to those found in Sweden's rivers and streams, and their results suggest that even small amounts of the drug can alter the behavior and the foraging rates of these fish.
The related report appears in the 15 February issue of the journal Science, which is published by AAAS, the nonprofit science society.
"While alone, fish that were exposed to Oxazepam dared to leave safe refuge and enter novel, potentially dangerous areas," explained Brodin. "In contrast, unexposed fish stayed hidden in their refuge. The exposed fish seemed much less s
|Contact: Natasha Pinol|
American Association for the Advancement of Science