Per- and Polyfluroalkyl Substances (PFAS)
Perfluoroalkyl and polyfluoroalkyl substances (PFAS), such as perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are part of a group of compounds used globally during the past century in manufacturing, firefighting and thousands of common household and other consumer products because of their heat, water, and oil resistance properties.
These compounds do not change or break down easily, and, as a result, they are very widespread in the environment and can accumulate in the human body. In recent years, experts have become increasingly concerned by the potential effects of high concentrations of PFAS on human health.
Recent Madison Water Utility testing has revealed that a number of Madison Wells have detectable levels of PFOA and PFOS contamination. Levels detected are well below the US Environmental Protection Agency Lifetime Health Advisory Level and are not considered a threat to human health, but given the lack of Wisconsin PFAS standards, a decision was made in March 2019 to take Well 15 offline until the state releases interim guidelines for a groundwater standard. Well 15 had the highest levels of PFAS contamination of all wells tested. It is expected that interim guidelines will be released later in 2019. In Madison, ongoing action planning to ensure the continued safety of drinking water is underway.
PFAS Health Advisories & Impacts
- EPA Lifetime Health Advisory Level
- Madison Well 15 and 16 PFAS Levels
- Varying Standards from Other States
- Potential Health Risks of PFAS
- Home Water Filtration
Monitoring & Action Planning
- City of Madison PFAS Response Team
- City of Madison Fish & Surface Water Testing
- Development of Wisconsin PFAS Standards
- Recommendations for Municipal and Private Well Testing
- More Information About PFAS
The U.S. Environmental Protection Agency (EPA) has set a Lifetime Health Advisory Level for two of the most commonly used and the most studied PFAS compounds in drinking water: perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS).
The PFOA and PFOS Lifetime Health Advisory is the level, or amount, below which no harm is expected from these compounds. The Lifetime Health Advisory Level is 70 parts per trillion (ppt) for PFOA and PFOS combined.
The EPA sets health advisories at levels that consider animal studies, human studies, sensitive populations and other exposures to PFAS that people may have in their environment. This information is used to establish an advisory level that provides a wide margin of protection because it is set far below levels that have caused health effects and is protective of everyone, including people who are pregnant, infants and children, and the elderly.
At this time, the EPA has not set health advisory levels for the other PFAS compounds. Since PFOA and PFOS were the most commonly used and manufactured of the PFAS compounds they are typically found in the majority of contamination sites and are more likely to be found in drinking water at higher concentrations than other PFAS. If Lifetime Health Advisory levels are adhered to for PFOA and PFOS, protections should be in place for the remaining PFAS.
Levels of PFAS in Madison Wells are well below the EPA Lifetime Health Advisory levels and are not considered a threat to health.
- EPA Lifetime Health Advisory for PFOA and PFOS combined: 70ppt (parts per trillion)
- Well 15: Testing has hovered around 12ppt of PFOA and PFOS combined since 2017. Various other PFAS compounds have been detected in Well 15 testing. No EPA Lifetime Health Advisory levels for these compounds exist.
- Wells 6, 9, 11, 14, 16: Levels of PFAS detected are too low to accurately quantify.
Detailed testing results can be found on the Madison Water Utility website.
Several states have reviewed the federal drinking water guidance and available peer-reviewed scientific research and have either issued drinking water standards that mirror or are more stringent than the EPA Lifetime Health Advisory.
The differences in the drinking water standards by states is based upon things like various uncertainties in the risk assessment process. This includes how much water people drink, different assumptions about exposure to PFAS from non-drinking water sources, technical considerations (e.g, the health impact being studied and considerations for sensitive populations), and social, political, and economic pressures of the impacted communities.
Currently, New Jersey and Vermont have the lowest PFAS standards. This does not mean that the EPA Health Advisory level or other states standards are not protective, but that New Jersey and Vermont have an even more protective standard due to differences in technical considerations of the information in the risk assessment process.
Scientists are still learning about the health effects that various PFAS can have on the body. The more widely used substances, like PFOS, PFOA, perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA), have been studied more than other PFAS.
Some, but not all, studies in humans with PFAS exposure have shown that certain PFAS may:
- Affect growth, learning, and behavior of infants and older children
- Lower a person’s chance of getting pregnant
- Interfere with the body’s natural hormones
- Increase cholesterol levels
- Affect the immune system
- Increase the risk of cancer
Scientists are still learning about the health effects of exposures to mixtures of PFAS.
Based on current research, the EPA Lifetime Health Advisory of 70ppt is set at a level to protect people, including sensitive populations like people who are pregnant and babies, from these health effects.
The EPA Lifetime Health Advisory also considers that not all PFAS exposure occurs through drinking water. PFAS are used in many common products that contribute to our total exposure. We can be exposed through dust in indoor air from furniture and carpets, from coatings on food wrappers or other consumer products treated with PFAS to resist stains. Understanding where exposure comes from can help us find ways to reduce exposure.
More information about health risk can be found from the Agency for Toxic Substances & Disease Registry.
Public Health Madison & Dane County’s advice is based on current available science.
When amounts of PFOA and PFOS in water are higher than the EPA Lifetime Health Advisory level of 70 ppt, we would recommend the use of bottled water or a filtration system certified to reduce PFOS and PFOA for drinking, cooking, making baby formula or food, washing fruits or vegetables, brushing teeth, or feeding pets.
Although levels of PFAS detected in Madison Wells are well below the EPA Health Advisory level, the City of Madison launched a PFAS Action Response Team in 2018.
This is a multi-agency action team that includes department’s representing water, human health, and the environment. We are actively monitoring the City of Madison’s water supply and working with the State of Wisconsin and National Guard to investigate sources and locations of PFAS contamination so we can continue to ensure safe drinking water. While we continue to monitor and mitigate resident’s exposure and learn more about this nationally emerging contaminant, we will keep the public informed.
The Madison Water Utility website contains more information about PFAS testing and other frequently asked questions.
In the Spring of 2019, the WI Department of Natural Resources will be testing fish that live in the surface waters of Starkweather Creek (likely near Olbrich Park). These areas will be tested due to the long-term use of fire-fighting foams at the Dane County Regional Airport and Truax Air National Guard Base.
Fish testing is important in this investigation because fish are predatory and eat other fish, meaning compounds that build up (bioaccumulate) will do so more in fish than in other animals. Therefore, it is important to test fish so we can provide any fish consumption advice.
We expect to find detectable levels of PFAS in the fish tissue, but based upon previous research done at PFAS-contaminated sites near Wisconsin’s river systems, we don’t expect that contamination will be high enough to change the current Dane County fish consumption advisories.
This is because current fish consumption advisories are protective of human health. What has been seen in other areas in Wisconsin is the fish consumption advisories for mercury and PCBs (polychlorinated byphenyl) are protective of PFAS because it limits the consumption of most of the same fish that accumulate PFAS. Fish testing results are expected in fall of 2019, and based on results, the advisories will be changed as needed.
In the absence of enforceable national standards, the Wisconsin Department of Natural Resources requested the Wisconsin Department of Health Services develop recommended standards for PFOA and PFOS for the protection of public health and provide these to DNR to use in the rule-making process.
For environmental investigations, Wisconsin is currently using EPA's Lifetime Health Advisory level of 70 parts per trillion for combined levels of PFOS and PFOA to evaluate potential for health impacts at locations where PFAS have been found in drinking water.
Testing the public water systems for PFAS is not a requirement. Residents should contact their municipality if they would like to know about PFAS testing in their community, however the majority of public water systems in Dane County do not test for PFAS.
Public Health Madison & Dane County recommends that public water systems and private well owners test for PFAS if they are near:
- A military base or area that has been used for firefighting activities
- An industrial area with frequent PFAS manufacture, disposal, or use
- A previously used landfill area
The following laboratories are able to analyze PFAS compounds in drinking water at low detection limits:
- ALS Global, Kelso, Washington. (360) 577-7222
- Eurofins, South Bend, Indiana. (574) 233-4777
- SGS AXYS, 2045 Mills Road W., Sidney BC Canada. (888) 373-0881
- TestAmerica, W. Sacramento, California. (916) 373-5600
- WeckLabs, City of Industry, California. (626) 336-2139