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Monday, Nov. 28, 2022

Did PFAS contamination cause a consumption advisory for fish in Lake Superior?


yes

The Wisconsin Department of Natural Resources and the Department of Health Services advised people to eat no more than one meal a month of rainbow smelt from Lake Superior in January 2021. The advisory followed the discovery of high levels of per- and polyfluoroalkyl substances, persistent contaminants known as "forever chemicals." 

Michigan's health department issued a similar warning in 2022.

PFAS are manmade chemicals that have been used in numerous industrial and consumer products for decades, including firefighting foam, which was used on a series of fires at a Superior oil refinery in 2018, causing elevated levels of PFAS in a creek that flows into Lake Superior.

In early 2020, samples for perfluorooctane sulfonate — the specific substance of concern detected in rainbow smelt — continued to average around 40 times higher than normal in the creek.

The substance has been linked to illnesses including cancer, fertility issues and developmental problems. 

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