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Environmental and Health Impacts of PFAS

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a large group of human-made chemicals that have been used in industry and consumer products worldwide since the 1950s.

PFAS do not occur naturally and are widespread in the environment. They are found in people, wildlife and fish all over the world. Some PFAS can stay in peoples' bodies a long time and do not break down easily in the environment.

In June 2022, the U.S. EPA revised their Health Advisory Levels (HALs) by adopting interim health advisories for PFOA and PFOS. Additionally, U.S. EPA issued two new health advisories for GenX and PFBS. The current health advisories reflect research conducted since 2016, showing negative health impacts can occur at much lower levels of contamination in drinking water.

2016 EPA Health Advisory
2022 EPA Health Advisory
70 ppt
0.004 ppt (interim)
70 ppt
0.02 ppt (interim)
10 ppt (final)
2,000 ppt (final)

The DNR and Wisconsin Dept. of Health Services (DHS) are carefully reviewing the technical information and justification that the EPA used to develop the updated HALs. While this review is in progress, DNR and DHS continue to use DHS’ recommended groundwater standards to determine when additional action is needed to reduce exposure. To date, DHS has recommended standards for 18 PFAS. You can find more information about DHS’ recommendations and how you can assess your risk using a Hazard Index on their PFAS website.

An enforceable public drinking water standard of 70 ppt for a combination of PFOA and PFOS went into effect in August.

Environmental Impacts

Conceptual site model for how PFAS may enter the environment from one source (firefighting foam applications).
Conceptual site model for how PFAS may enter the environment from one source (firefighting foam applications). Source: ITRC

Drinking Water and Wells

According to public health experts, people can come into contact with PFAS by eating food, like fish, drinking water and breathing air that contains PFAS. Most non-worker exposures occur through eating food that contains PFAS or drinking contaminated water (please see the 'Health Impacts' tab for more information).

At the request of the DNR, the Wisconsin Department of Health Services (DHS) reviewed scientific literature to determine if there is sufficient toxicological information to recommend a groundwater quality standard for other PFAS compounds found in Wisconsin. Of the 36 compounds evaluated by DHS, they recommended health-based groundwater enforcement standards for 18.


In Wisconsin, persons who own properties that are the source of PFAS contamination, or who are responsible for discharges of PFAS to the environment, are responsible for taking appropriate actions.

PFAS in soil may pose a direct contact risk to humans or result in chemicals entering the groundwater and surface water. The DNR's Remediation and Redevelopment (RR) Program maintains a web-based spreadsheet with soil residual contaminant levels (RCLs) that were calculated using U.S. EPA's regional screening level (RSL) web calculator, and following the procedures in NR 720.12, for determining soil direct-contact RCLs protective of human health.


PFAS can be emitted into the air as vapors or fine particles. PFAS then travels in the atmosphere through adhesion to particulate matter. PFAS compounds, with the exception of ammonium perfluorooctanoate, are not currently regulated as hazardous air pollutants in Wisconsin.

There are currently no federal (U.S. EPA) approved sampling methods for PFAS compounds in ambient air. Furthermore, health benchmarks that estimate safe exposure levels are available for only a few of the many PFAS compounds that are present in the environment. The lack of test methods and emissions data from potential sources of PFAS compounds makes further study in Wisconsin necessary.

For more information on air quality in Wisconsin, see the air quality monitoring page and the air pollutants and standards page.

Fish and Wildlife

PFAS accumulation in wildlife is an emerging area of interest and little is known about the possible effects of PFAS accumulation in wild animals and fish. PFAS is known to accumulate in exposed animals. In other examples of environmental chemicals that accumulate in the food chain, fish are a known and important source of exposure to humans. Studies of the association between fish consumption and PFAS accumulation in humans provide evidence that fish are an important exposure source with this class of chemicals as well.

Some PFAS would be expected in samples from any wild animal. The DNR does not have a way to predict how much PFAS might be in any wild animal based solely upon PFAS in the environment. In other examples of chemicals that accumulate in the food chain, the highest source of exposure for people tends to be fish.

Health Impacts

Exposure Routes and Health Impacts

PFAS contamination may be in food, drinking water, indoor dust, some consumer products and workplaces.

In EPA's health advisory documents for PFOS and PFOA, EPA reviewed the research pertaining to the sources of PFAS exposure. They concluded that diet is the major contributor of exposure to PFAS compounds, with drinking water and/or dust being additional exposure sources.

The Wisconsin Department of Health Services (DHS) [exit DNR] has additional information on PFAS, and the U.S. Environmental Protection Agency [exit DNR] and the Agency for Toxic Substances and Disease Registry [exit DNR] also provide additional health information on PFAS, including PFAS investigation and remediation efforts by other states.

More information is available on the Consumption Advisories and PFAS page.


Wisconsin Resources

To view PFAS sites involving the DNR, please go to the DNR's Remediation and Redevelopment Program database (BRRTS on the Web). To find sites with PFAS contamination in the database, please go to the "Advanced Search" tab, and under "Substances" search for "PFAS."

The Wisconsin Dept. of Health Services has health-related information about Per- and Polyfluroalkyl Substances (PFAS) [exit DNR].

Additional Resources