When Wisconsin Department of Natural Resources officials announced last month that they had found high levels of PFAS chemicals in Lake Superior smelt — high enough to warn people to limit how much smelt they eat — it left many people who follow fish consumption advisories scratching their heads.
First, smelt are small and have relatively short lifespans, and so shouldn’t be bioaccumulating toxins in high levels. The general rule with traditional fish contaminants — like mercury, PCBs and dioxins — are that bigger fish higher in the food chain are usually the highest threat for passing along contaminants to people, fish like sharks in the ocean and musky, trout and big walleye in Northland lakes and rivers. Read more…
