Male Fish Exposed To Flushed Drugs Develop Ovaries

Bridgette Bornstein
WCCO St. Cloud, Minn.

It may be difficult to tell if fish are crying when they’re already surrounded by water, but researchers do know for a fact that some of them are on Prozac.

While it may sound like a surreal joke, scientists at a St. Cloud State University laboratory are concerned by what they’re finding in Minnesota waterways.

According to the research, prescription drugs flushed down toilets are turning up in the fishes’ home.

“There are cases where fish don’t react normally because they are exposed to antidepressants, for example,” said Heiko Schoenfuss, St. Cloud State associate professor of anatomy.

As it turns out, fish being exposed to drugs isn’t the whole story. Scientists are also finding that some personal care products — including some soaps — are having a troubling effect on fish.

“We’re finding that some of these compounds will actually feminize male fish, which is kind of scientific lingo for saying that the male fish will take on certain traits that we usually only find in female fish,” said Schoenfuss.

In the most extreme cases, male fish are developing ovaries.

Many may assume those compounds would get filtered out at waste water treatment plants, but it’s not easy to treat all of them.

Scientists are concerned that if pharmaceuticals keep getting flushed down the toilet and certain cleaning compounds keep going down the drain, there could be long-term problems for fish.

“I guess as far as fish are concerned, when you live in Minnesota, there’s a legacy that we want to protect. We don’t want to hurt our fish populations in the long run,” said Schoenfuss. “It’s a deformity, it’s an anomaly and it probably affects the reproductive ability. Of course if you have enough male fish that can’t reproduce, ultimately the population could suffer.”

Scientists stress this is not only an issue in Minnesota. They have also found feminine traits in male fish across the country from the Potomac River in Washington, D.C. to waterways in southern California. (© MMVII, CBS Broadcasting Inc. All Rights Reserved.)