DNR Adopts the Department of Health Services’ Recommended Hazard Index (HI) Approach for Evaluating Human Health Risk of Certain PFAS due to Ingestion of Drinking Water
On Nov. 6, 2020, the Wisconsin Department of Health Services (DHS) provided the Wisconsin Department of Natural Resources (DNR) recommended groundwater standards for 16 PFAS substances (known as “Cycle 11”). Shortly thereafter, DHS provided recommendations to DNR for utilizing a hazard index approach to assess the cumulative risk of these PFAS, including PFOA and PFOS from Cycle 10. The hazard index risk assessment approach is used to assess the cumulative risks of compounds with similar health effects that are typically found as mixtures in environmental samples. This approach has been employed by DHS to evaluate certain classes of pesticides and volatile organic compounds as well as by the United States Environmental Protection Agency (EPA) to evaluate the risk posed by non-carcinogenic chemicals found at Superfund sites.
DNR and DHS are now using this approach to evaluate when temporary emergency water should be provided by the state or responsible party. DHS recommends utilizing bottled water, or another safe alternative drinking water supply, if the hazard index is equal to or greater than one. More information on the hazard index and availability of temporary emergency water is available on the DNR’s PFAS webpage. Please note that the hazard index tool is not intended to be used to develop cleanup standards under ch. NR 722.
PFAS 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 through accidental spills of PFAS-containing materials, discharges of PFAS-containing wastewater to treatment plants and certain types of firefighting foams.
PFAS do not break down easily in the environment and have been discovered at concentrations of concern in groundwater, surface water and drinking water. These chemicals are known to bioaccumulate in the tissues of fish and wildlife and are also known to accumulate in the human body, posing several risks to human health.
Addressing PFAS contamination in the environment is part of Gov. Tony Evers’ statewide initiative to ensure Wisconsinites have access to safe drinking water. In 2019, the governor signed Executive Order #40 to address the issue of PFAS across the state.
The governor’s 2021-23 biennial budget unveiled in February proposes significant resources for the monitoring and testing of PFAS including over $20 million over the next two years for assistance and resources to local communities that are impacted by PFAS contamination, aiding local fire departments in disposing of PFAS foam, and adding additional DNR staff to implement the Wisconsin PFAS Action Council’s action plan.
The DNR has undertaken several measures to mitigate PFAS contamination, including establishing the Wisconsin PFAS Action Council (WisPAC) in 2020 and spearheading the creation of the statewide PFAS Action Plan. The plan includes 25 action items centered around four guiding principles: environmental justice, health equity, innovation, and pollution prevention.
Additional information on PFAS is also available on the Wisconsin DHS website and the Wisconsin DNR website.