Don’t toss your unused meds down the drain; use unscented personal-care products.

Eye opener: If chemicals in the water are contaminating fish, they're probably contaminating us, too.

RODALE NEWS, EMMAUS, PA—Scientists have found several pharmaceuticals and personal-care compounds in fish collected from 5 rivers across the country. The study will be published in a special online edition of the journal Environmental Toxicology and Chemistry.

THE DETAILS: Baylor University researchers, who have been studying emerging contaminants in water for years, worked with the Environmental Protection Agency (EPA) and tested rivers that receive water from treatment plants in Chicago, Dallas, Orlando, Phoenix, and the Philadelphia suburb of West Chester. Scientists tested fish at all the sites for 24 different human medications and 12 chemicals commonly used in personal-care products, and found that every river contained fish with 7 human drugs and 2 personal-care product ingredients.

The detected chemicals included an over-the-counter antihistamine; medications that treat blood pressure, epilepsy, and bipolar disorder; and antidepressants. Gemfibrozil, used to treat high cholesterol and triglyceride levels, was found in the livers of wild fish. Two fragrance ingredients used in soaps and other personal-care products were also detected in the fish, and they registered in higher amounts than the drugs.

WHAT IT MEANS: This isn’t good news for fish, and we don’t know what it means for people. “If [the chemicals] are in fish, then they also may be in humans,” says Anne Steinemann, PhD, University of Washington water researcher and Rodale.com advisor. The good news is that eating the contaminated fish is unlikely to expose you to the contaminants in significant amounts—you’d have to eat thousands of these fish to get a single dose of Prozac. But the drug contamination is clearly messing with fish function. Previous studies suggest antidepressants in water accumulate in fish and cause behavioral changes that interfere with their ability to mate and reproduce. The drugs also affect fish aggression. The effects of the fragrance chemicals on fish or people haven’t been well studied.

Here are some steps you can take to keep chemicals out of your local waters: