Health

‘Forever chemicals’ prompt new, stricter advice for eating fish from Mississippi

A dam along the Mississippi River
Tthe Ford Dam along the Mississippi River between Minneapolis and St. Paul on Oct. 6, 2022.
Tim Nelson | MPR News

Concerns about pollutants including "forever chemicals” have prompted state health officials to issue new guidelines for eating fish from a stretch of the Mississippi River between St. Paul and Wabasha.

The new recommendations apply to Pool 2 of the Mississippi from St. Paul’s Ford Dam to Hastings, Pool 3 from Hastings to Red Wing, and Pool 4 from Red Wing to Wabasha, as well as connected Minnesota lakes and backwaters.

A recent data analysis of fish pulled from the Mississippi between pools 2 through 4 prompted the change in guidance, said Angela Preimesberger, fish consumption guidance scientist with the Minnesota Department of Health. 

“We did find that per- and polyfluoroalkyl substances, or PFAS, are found in higher concentrations and a larger number of mixture of contaminants in these fish than we see on average,” Preimesberger said.

The health department advises people who are pregnant or may become pregnant, are breastfeeding or plan to breastfeed, and children under 15 should not eat fish from those locations. 

“It’s that developing human that is most sensitive to potential health impacts from PFAS,” Preimesberger said. 

Others — including older adults and those who aren’t planning to get pregnant — should limit their consumption of fish from those waters to one serving a month, she said.

The new guidance expands on recommendations the health department made last year that sensitive groups avoid eating fish from the Ford Dam in St. Paul to the Hastings dam, as well as Lake Rebecca near Hastings.

“Having to tell certain people that they can’t eat the fish is something we don’t take lightly, because there are of course trade-offs,” Preimesberger said. “If you are used to eating fish and that's part of your diet, to switch to something else can have implications for your health.”

Better methods of detecting PFAS, as well as a better scientific understanding of their health impacts — even at low levels — also factored into the decision, she said.

PFAS are human-made chemicals that were produced starting in the 1940s by Maplewood-based 3M and have been widely used for decades. They don't break down in the environment and can accumulate in fish and in people.

Some PFAS have been linked to negative health effects including developmental problems and cancer.

The Minnesota Pollution Control Agency is investigating whether the PFAS traces back to 3M’s historic activities or is from another source — and whether any corrective action is needed, said Liz Kaufenberg, a manager in the Minnesota Pollution Control Agency’s Superfund site assessment section. 

Last year, state lawmakers passed a far-reaching ban on PFAS in many products starting in 2025. Called Amara’s Law, it was named for Amara Strande, who grew up in Oakdale and attended Tartan High School. She died of cancer in April 2023, a few days before her 21st birthday.

By 2032, no product with intentionally added PFAS could be sold in Minnesota unless state officials decide it's essential for the health, safety or the functioning of society, and there are no reasonable alternatives. 

It’s likely that more Minnesota water bodies could see fish consumption advisories due to PFAS levels in the future.

Last year, the Legislature provided funding for the Department of Natural Resources to expand fish monitoring and test for PFAS along with other contaminants such as mercury and PCBs, Preimesberger said.

“That's going to give us a lot more information to help identify if there's waters of higher concern than average,” she said.