Anti-anxiety drug causes fish to live longer, study says

This circa 2009 photo provided by Bent Christensen shows a perch in Sweden. (AP Photo/Bent Christensen)

On the one hand, fish exposed to the tranquilizer oxazepam when it seeps into their waters kind of become jerks, reports a study in Nature. On the other hand, this same drug, a benzodiazepine used to treat anxiety and insomnia in human adults, apparently helps them live longer, reports Nature World News, citing a study published in the journal Environmental Research Letters.

This news may be, from a longevity standpoint, terrific for the tainted fish—but it's not ideal for keeping the entire ecosystem's mortality rates balanced and the food chain intact.

Swedish researchers gathered eggs from a population of lake perch and exposed them to varying levels of oxazepam as the embryos grew, notes Phys.org. When the fish finally hatched, scientists found that perch subjected to higher doses of the benzo had lower mortality rates than ones that received lower concentrations or none at all.

The team says these results could simply be scratching the surface in exposing how pollutants affect marine creatures. "Even though our study focused on one single pharmaceutical contaminant, it is possible that similar effects could be induced by exposure to a whole range of pharmaceuticals that find their way into surface waters, such as antibiotics, painkillers, anti-inflammatory drugs, hormones, and antidepressants." (Read more about what compounds may be finding their way into the US water supply.)