The results mean that advice on how much fish can be eaten safely from those walleye lakes will not be impacted by PFCs.
The lakes tested include some of the most popular in the state and account for about 40 percent of the walleye harvest: Cass, Kabetogama, Lake of the Woods, Leech, Mille Lacs, Rainy, Upper Red Lake, Vermilion and Winnibigoshish.
"Minnesotans can continue to enjoy the benefits that come from eating fish from some of their favorite lakes without concern for PFCs," said Pat McCann, Minnesota Department of Health fish advisory program manager. "People should continue to follow the existing consumption advice for those lakes, which is based on mercury."
The 10th largest walleye lake is Lake Pepin, part of the Mississippi River, which had been previously tested and had levels of PFCs that led to recommendations to limit consumption for some species. PFCs are a family of man-made chemicals that have been used for decades to make products that resist heat, oil, stains, grease and water.
After PFCs were discovered in fish from Lake Calhoun in the metro area in 2007, state officials began to look for PFCs in fish from other waters of the state. PFOS is the perfluorochemical that accumulates most in fish.
Under the 2010 testing, state scientists retested some of the waters, or connected waters, that had higher levels of PFCs in fish from previous testing. The levels found were similar to previous measurements. New waters tested for PFCs included several rivers in Greater Minnesota and some additional metro area lakes. Results from the testing indicate no need for advice to limit consumption in any new areas based on PFCs. Those waters may have existing advice to limit consumption based on mercury or PCBs.
The 2010 collections of PFC data will be included, along with new data on mercury and PCBs, when MDH updates its fish consumption guidelines in June. The guidelines provide consumers and anglers with information to help them make choices about the fish they eat. The Department of Natural Resources collects fish for testing by the state Department of Agriculture. The Health Department then analyzes the test data and establishes the consumption advisories.
"Most people can benefit from including more fish in their diet," said McCann. "Fish are a great source of low-fat protein. Eating fish contributes to brain and eye development in the growing fetus. The omega-3 fatty acids found in fish may promote heart health for adults. We strongly encourage Minnesota residents to follow the advice in the guidelines and eat fish that are low in contaminants."
For more background on perfluorochemicals in Minnesota, go to www.health.state.mn.us/divs/eh/hazardous/topics/pfcshealth.html
Statewide safe eating guidelines are available online at www.health.state.mn.us/divs/eh/fish/eating/safeeating.html.
The fish consumption advice can also be accessed through a new DNR application for Android smartphones at www.dnr.state.mn.us/mobile/index.html.