ST. PAUL  (AP) -- A government study finds that potentially harmful chemicals and pharmaceuticals are widespread in Minnesota streams.

The study by the Minnesota Pollution Control Agency also shows fish undergo genetic changes when exposed to the mix of chemicals.

Agency scientist Mark Ferrey says the substances that scientists most often found included antibiotics, antidepressants and a drug used to treat attention deficit hyperactivity disorder.

The agency's scientists collected water samples from 25 sewage treatment plants across Minnesota. They also sampled water upstream and downstream from the treatment plants for 78 chemicals.

He says the drug compounds are all found at very low concentrations, but that doesn't mean they're harmless. He says more research is needed to understand the effects on aquatic life

(Copyright 2011 by The Associated Press.  All Rights Reserved.)

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