A U.S. Fish and Wildlife Service employee samples river water for endocrine disrupting pollutants.
Study results publicized this week suggest Twin Cities water resources and the Mississippi River downstream from the Cities are suffering from pollution by road salt and endocrine disrupting chemicals.
The results are from U.S. Geological Survey analysis of watersheds around the U.S. The road salt results indicate chloride levels that may imperil aquatic life in creeks and rivers in the Twin Cities. A study by the University of Minnesota released last winter found that about 70% of the salt applied to roads in the area remained in the Mississippi River and tributaries. Nearly 350,000 tons of road salt are applied for de-icing in the Twin Cities metropolitan area annually.
The U.S.G.S. also reported that 73% of male smallmouth bass sampled in the Mississippi River near Lake City, Minnesota have characteristics of both genders, which researchers believe may be the result of exposure to endocrine-disrupting compounds in wastewater.
The Minnesota Legislature earlier this year appropriated funds provided by the state’s new conservation tax to continue and expand a study of endocrine-disrupting chemicals in wastewater conducted by the state Pollution Control agency. The Minnesota Department of Health has also received state funds to evaluate endocrine disruptors in the state. Targeted materials include PCBs, heavy metals, household compounds such as laundry detergent and shampoo, and many pharmaceuticals.
A local nonprofit organization, Friends of the Mississippi River, hosted a 2007 presentation by University of California researcher Dr. Tyrone Hayes about work he has done linking low levels of atrazine, a widely used agricultural herbicide, with feminization of amphibians. A 2008 state study found atrazine even in high-quality lakes in the Boundary Waters Canoe Area Wilderness, suggesting the chemicals are also being transported through the air. Also in 2008, a state Pollution Control Agency staffer alleged in a lawsuit that he was fired for being a whistle-blower about atrazine pollution in the state. He later dropped the suit. The researcher, Paul Wotzka, continues to speak out publicly, recently telling Minnesota Public Radio that says animal tests tie atrazine in small amounts to birth defects. “If you were pregnant mother, drinking water in June and you had these high spikes of atrazine in your water, you would want to know about them,” he said.
Last winter’s University of Minnesota road salt report urged more judicious application, observing that the school had reduced its use of the de-icer 41% through such an initiative.
Photo credit: U.S. Fish and Wildlife Service.