ST. PAUL (AP) - A Minnesota Pollution Control Agency study finds trace levels of pharmaceuticals and other chemicals may be harming fish in Minnesota rivers and lakes.

Recent studies found a variety of pharmaceuticals and other chemicals in Minnesota waters, ranging from antidepressants to insect repellant. But, the new study confirms how common these chemicals are in surface water, albeit at very low levels.

The agency took samples from 50 river locations across the state and tested for 146 chemicals. The study found the most common chemical found is iopamidol. That's a contrast agent that's injected into a patient before an X-ray or scan to make blood vessels and organs stand out in the images. Other common findings include antidepressants, antibiotics and anti-corrosion chemicals.