U.S. EPA Releases Draft Maximum Contaminant Levels for PFAS Compounds in Drinking Water

U.S. EPA Releases Draft Maximum Contaminant Levels for PFAS Compounds in Drinking Water

Today, the U.S. Environmental Protection Agency (EPA) released draft standards for six PFAS compounds in public drinking water. The proposed standards include an enforceable Maximum Contaminant Level (MCL) of 4 parts per trillion (ppt) for PFOA and PFOS with a goal (i.e., Maximum Contaminant Level Goal; MCLG) of 0 ppt. Additionally, EPA proposed a hazard index of 1.0 for mixtures of four additional PFAS compounds (i.e., GenX, PFBS, PFNA, and PFHxS).

A hazard index accounts for potential risks from exposure to a mix of contaminants. These proposed rules acknowledge the importance of limiting exposure to PFAS and the role that drinking contaminated water plays in impacting health risks.

Wisconsin’s Department of Natural Resources (DNR) and Department of Health Services (DHS) recognize the need to assess risks to human health from mixtures of PFAS and appreciate the steps EPA has taken here. Both agencies will review the proposed standards and accompanying documents and monitor the federal rulemaking process as the EPA works toward a final rule.

Wisconsin’s DHS currently provides health advice for individual PFAS compounds and uses a hazard index to assess risk from mixtures of PFAS in drinking water.

The state’s enforceable standard of 70 parts per trillion (ppt) for PFOA and PFOS in public drinking water has not changed since going into effect in August 2022. The state continues to recommend public water systems take voluntary actions to reduce PFAS in drinking water if levels are at or above DHS’ health advisories. Once EPA completes its rulemaking process, the DNR will work to align the state’s standards with the federal standards. The DNR will also assist public water systems with planning to comply with the proposed federal standards.

The public can view sampling results for public drinking water systems sampled for PFAS under Wisconsin’s drinking water standards or through the voluntary program in the Interactive PFAS Data Viewer. Data for public water systems are added to the Interactive PFAS Data Viewer as they become available, with at least one sample being required of public water systems by the end of 2023.

PFAS, per- and polyfluoroalkyl substances, are a group of human-made chemicals used for decades in numerous products, including non-stick cookware, fast food wrappers, stain-resistant sprays and certain types of firefighting foam. These contaminants have made their way into the environment in a variety of ways, including spills of PFAS-containing materials, discharges of PFAS-containing wastewater to treatment plants, and use of certain types of firefighting foams.

Visit the Wisconsin DNR website to learn more about measures undertaken to mitigate PFAS contamination in Wisconsin, including creating and implementing the PFAS Action Plan.