Study: Trace medications, chemicals may be harming fish
Posted January 12
ST. PAUL, Minn. — 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, Minnesota Public Radio News (http://bit.ly/2jA1Up5 ) reported. 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.
"Chemicals, even at those concentrations, can cause adverse effects in fish and wildlife that we're really just starting now to be able to understand," said Mark Ferrey, a MPCA scientist.
He added that some chemicals at significantly low levels change the response genes.
"Maybe they're not toxic," Ferrey said. "But they throw some physiological switch that takes an organism down an entirely different pathway of growth, reproduction and behavior that can be very important."
At the moment, Ferrey does not have funding for more studies, but he thinks the next step is to recognize which chemicals have the most negative effect on fish or other species, and determine ways to remove those contaminants from the environment.