Report: Wastewater is key contributor of 'forever chemicals' pollution

water flowing out of a faucet
PFAS, or per- and polyfluoroalkyl substances, are a large class of human-made chemicals originally developed in Minnesota by Maplewood-based 3M back in the 1940s. PFAS have been found in water, soil, wildlife and humans around the globe.
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A new report from an environmental advocacy group says wastewater treatment plants and sewage sludge are key pathways for so-called “forever chemicals” to contaminate Minnesota waterways. 

The report, by the nonprofit Minnesota Center for Environmental Advocacy and a University of Minnesota professor, says Minnesota state agencies need to take stronger action to regulate PFAS in wastewater, as other states have done.

PFAS, or per- and polyfluoroalkyl substances, are human-made chemicals used in a variety of products, from nonstick cookware to firefighting foam.

They don’t break down in the environment and have been found in humans and wildlife across the globe. Some PFAS have been linked to health problems, including low birth weight, kidney and thyroid disease and cancer.

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The report’s authors cite two main pathways for PFAS pollution: Wastewater treatment plants collect PFAS-contaminated wastewater from industries, landfills and airports, but they're not equipped to remove the chemicals, said Carly Griffith, water program director at the Minnesota Center for Environmental Advocacy.

The treated wastewater is then discharged into lakes, rivers and streams.

“That carbon-fluorine bond, one of the strongest bonds in organic chemistry that really sets these compounds apart and has also made them useful to industry, also means that our current wastewater treatment technologies aren't able to remove them from wastewater streams,” Griffith said.

After wastewater is treated, leftover biosolids — sometimes called sewage sludge — are frequently spread on farm fields as fertilizer. PFAS in biosolids can leach into groundwater or nearby surface waters, the report says.

Matt Simcik, a professor at the University of Minnesota’s School of Public Health, contributed to the report. He said field testing on three streams in the St. Cloud area, where use of biosolids on farm fields is widespread, found considerably higher PFAS levels than rivers in areas where biosolids were not applied. 

The report’s authors say state agencies should require industrial facilities to remove PFAS from their wastewater before sending it to treatment plants. 

They also want to add PFAS as a pollutant under Minnesota’s management rules for sewage sludge, so wastewater treatment plants would be required to test biosolids intended to be spread on farm fields for the chemicals.

They say these actions are a critical next step to tackling the PFAS problem, following the Minnesota Legislature’s action this year banning the non-essential use of the chemicals beginning in January 2025.

Called Amara’s Law, it was named for Amara Strande, who died of cancer in April. Her family blamed her illness on PFAS in the water at their Oakdale home and Tartan High School, where she attended.

In June, the Minnesota Pollution Control Agency released a report that estimated the cost to clean up PFAS from wastewater streams across the state at $14 billion to $28 billion over the next two decades.

In a statement, the MPCA said it continues to advance plans outlined in the state’s PFAS blueprint, which outlined strategies to prevent PFAS pollution.

The agency said it’s collected monitoring data from wastewater treatment plants and is working with cities to identify and reduce sources of PFAS in their communities. It will conduct additional monitoring that could help inform its decisions on future permits, including for wastewater, it said.

The U.S. Environmental Protection Agency is currently assessing the risk of two common PFAS chemicals in biosolids to human health. It’s expected to release its findings this winter.