High Levels Of Wastewater Chemicals Found In Minnesota’s Lakes, Rivers

Pharmaceuticals, cocaine, and a variety of other chemicals are more widespread in Minnesota’s lakes and rivers than previously thought.

That’s according to two studies released yesterday by the Minnesota Pollution Control Agency (MPCA).

Researchers have long found chemicals near wastewater treatment plants, but the new studies show they are also found in lakes and rivers far from these facilities.

The insect repellant ingredient DEET was found in 76 percent of Minnesota’s lakes in the study. An antidepressant and a veterinary antibiotic were the most frequently found pharmaceuticals. Cocaine was also detected in the lakes, along with hormones and plastic ingredients.

Minnesota’s rivers tell a similar story, with food and cosmetic preservatives known as parabens found in about a third of the tested waters.

Mark Ferrey is an environmental scientist with MPCA who coordinated the study. He says many of the chemicals were found at low levels. Ferrey says research is underway on how the chemicals affect wildlife and humans, although he says much more is needed.

“We need to be a little bit more cautious, perhaps, about what we’re using and what we’re flushing down the drain and what gets out into the environment – because we might be damaging the things we love a lot about our environment without even knowing it.”

Research shows that chemicals called endocrine-disrupting compounds act like hormones and have affected reproduction and growth in some fish. Many of these chemicals turned up in the study.

Wisconsin Department of Natural Resources Water Quality Bureau director Susan Sylvester says she doesn’t have the budget to conduct similar tests. She says she’d want to develop a plan first on how to use the results once the study was completed.