The Michigan Department of Health and Human Services is advising people to limit consumption of some fish from seven lakes in Michigan, including Lake Michigan and Lake Huron.
The recommendations are the result of tests finding elevated levels of harmful chemicals in commonly eaten parts of rainbow smelt and carp caught in the lakes.
The health department said the new rainbow smelt guidelines are based on elevated levels of a chemical called perfluorooctane sulfonate — a member of the PFAS family — found in the fish. The guidelines for carp are based on elevated levels of polychlorinated biphenyls, or PCBs.
Neither chemical readily breaks down in the environment, and both are associated with an array of health problems.
The guidelines recommend that Lake Huron fishers limit their consumption of smelt to six servings per year and Lake Michigan fishers limit to one serving per month.
The health department issued a "do not eat advisory" for carp from Thompson Lake in Livingston County and a "limited advisory" for carp from the county's Earl Lake. The limited advisory means people under age 15, those with health problems such as cancer or diabetes, and those who might have children in the next several years, are pregnant or are breastfeeding should avoid eating carp from Earl Lake.
Still, Brandon Reid, a toxicologist with the state health department, said the guidance is not meant to discourage people from eating fish entirely.
"Fish are still a very, very good food option. They're very healthy, they're full of nutrients," Reid said. "We want people to keep eating fish. We don't want people to say, 'There's chemicals in fish, so we're not going to eat fish anymore,' but we want to put that information out there so people ... make their own choices about what they're comfortable eating."
The health department usually releases updated guidelines each April. This year, Reid said, the department published some advisories early after finding the elevated chemical levels
