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MDCH Issues "Do Not Eat" Fish Advisory for Clarks Marsh in Iosco County

LANSING - The Michigan Department of Community Health (MDCH) has issued a "do not eat" advisory for all fish taken from Clarks Marsh, south of the former Wurtsmith Air Force Base, in Iosco County. Pumpkinseed and bluegill fish samples were collected from the marsh in 2011. Laboratory analysis of the samples indicates that levels of perfluorinated chemicals (PFCs) in the fish are too high for people to safely eat.

Currently there are no PFC data for fish from the Au Sable River near the marsh, however MDCH advises that people do not eat fish taken from the river south and east of Clarks Marsh.

The MDCH bases this fish consumption advice on reference values used by the U.S. Environmental Protection Agency (EPA) and the Minnesota Department of Health.

While only smaller fish from Clark's Marsh have been analyzed, scientific information suggests that as larger, predatory fish eat the smaller fish, the PFCs will build up in the edible flesh, therefore the fish advisory covers all species. For the Au Sable River upstream from Clarks Marsh, people should follow the fish consumption advice in the Michigan "Eat Safe Fish" Advisory, at or call (800) 648-6942.

PFCs are chemicals that are used in fire-fighting foams, non-stick ("Teflon") manufacturing, electroplating, and textiles. They are of concern because they are persistent in the environment and the food chain and can result in health hazards to humans. The only known site of PFC contamination in Michigan is the former Wurtsmith Air Force Base in Oscoda. MDCH is working with the Michigan Department of Environmental Quality and the EPA to determine the nature and extent of this issue.