Minnesota finds increased health risk from ‘forever chemicals’

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.
Steve Johnson for Pexels

Updated: Jan. 17, 12:05 p.m.

Perfluorinated chemicals have been widely used for decades in firefighting foam and many household items. They are widespread in the environment and in human bodies and do not break down in the environment.

The large class of manmade chemicals was originally developed in Minnesota by Maplewood-based 3M.

Based on the latest human research, the Minnesota Health Department has updated the health-based values for the chemicals for the sixth time, said Environmental Surveillance and Assessment Manager Sarah Fossen Johnson.

Some of the levels at which health risks are thought to begin were significantly lowered.

A large water treatment tank
Water treatment tanks in a temporary facility in Cottage Grove.
Ben Hovland | MPR News 2023

For example, PFOA non-cancer health risk level was reduced from 34 parts per trillion to .24 parts per trillion. That level is so low it cannot be detected by current test methods. The health department is working on more sensitive testing methods.

“It’s important to note that these are calculated to protect the most sensitive populations and the most highly exposed. So generally that's going to be bottle-fed infants and children,” said Johnson.

These state levels are intended to provide health risk guidance. They do not change current drinking water standards.

The federal Environmental Protection Agency is expected to soon release new maximum contaminant levels (mcl) which are enforceable drinking water standards and could lead to more Minnesota cities treating water for “forever chemicals.”

Still, Johnson expects the federal levels will be three times higher than the guidance released by the state.

Department of Health officials consider only health risk when they set the health-based values, said Johnson, while the EPA also takes into account the economic cost of removing contaminants to meet the standards set for drinking water.

A person pours water in a tube
A water researcher, pours a water sample into a smaller glass container for experimentation as part of drinking water and PFAS research at the U.S. Environmental Protection Agency Center For Environmental Solutions and Emergency Response.
Joshua A. Bickel | AP

Research has found humans are very sensitive to perfluorinated chemicals, said Johnson. Some research found children exposed the chemicals had a lower immune response to vaccines.

“So there’s a concern that there could be an immune impact. However, we do not have a direct measure of what that is. We just know that the immune system is not responding as robustly as we would like to see,” Johnson said.

Minnesota has been working to clean up areas directly contaminated by perfluorinated chemicals in the east metro. The new health risk level could cause some expansion of those efforts.

“There may be a need to go out and mitigate, to go out and put granular activated carbon systems, as an example, on private wells,” said Tom Higgins, superfund remedial section manager at the Minnesota Pollution Control Agency.

“We’ve estimated that the total costs for protecting drinking water as a potential exposure pathway based on the new federal standards that are being proposed by EPA, as well as new state health-based values may likely exceed $1 billion,” said Higgins.

State officials are not recommending individuals test private wells for the chemicals. Johnson said the test is very expensive and sensitive.

The least expensive approach is to reduce exposure to the chemicals by eliminating them in as many products as possible, which is part of the state response plan, Higgins said.

Individuals should look for ways to reduce exposure to the chemicals by avoiding or replacing items that contain perfluorinated chemicals.

Correction (Jan. 17, 2024): The maximum contaminant levels soon to be released by the EPA will be new, not updated. The story has been revised.