Pharmaceuticals Anonymous

Friday, September 4, 2009

Environment: Antidepressants make for sad fish

Link at Science News
and at Science News for Kids

"While medications are meant to help a person feel better, they're not good for wildlife. Over the past several years, scientists have begun to test how common drugs are in freshwater ecosystems. Researchers also are starting to learn more about how medications meant for humans affect the animals that accidentally ingest the drugs.

Recently, several scientists tested how a group of drugs called antidepressants affects freshwater fish. For many people with an illness called depression, antidepressants can be lifesavers. People with depression may feel sad or anxious for extremely long periods of time, lose interest in activities they once enjoyed and have difficulty sleeping or concentrating. Antidepressants help improve these symptoms for some people.

Several years ago, researchers discovered that some species of fish living near wastewater treatment plants had antidepressants in their brains. "Pretty much any water sample in the vicinity of a wastewater treatment plant will test positive for some group of antidepressants," says chemist Melissa Schultz, of the College of Wooster in Ohio. This finding inspired a number of scientists to learn how these drugs affect fish and other wildlife.

In their experiments, researchers exposed species of fish in a laboratory to different brands of antidepressants. Then, the scientists tested the fishes’ responses to a number of things, such as the cues predators make or the appearance of prey animals.

Some hybrid striped bass exposed to the antidepressant Prozac eventually began hanging vertically in the water — a highly unlikely pose — and stopped eating.

The researchers found that antidepressants affect fish species in numerous ways, from diminishing their response to predators to slowing down their prey-hunting techniques. One unexpected result even showed that a type of antidepressant called fluoxetine acts like estrogen, a primarily female hormone, when in the bodies of adult male fathead minnows.

Fluoxetine, sold under the brand name Prozac, caused these male minnows to produce an egg protein normally made only by females. In addition, males exposed to fluoxetine did not make the bright colors and facial bumps usually used to attract mates. More testing needs to be done to determine whether these changes affect minnows' ability to mate."

Kay Jamieson and John McManamy say the brain is like a pond, an ecosystem, but they want to put drugs into it. We hope they don't keep goldfish.