Today, CSWAB petitioned the Wisconsin DNR for a reassessment of the state’s Groundwater Health Advisory Level (HAL) for a PFAS chemical known as PFBS. If approved, the toxicological review is expected to reduce the State’s current HAL from 450,000 ppt (parts per trillion) to only 3,000 ppt – making it far more protective of human health and the environment.
The persistence and mobility of PFBS and other PFAS chemicals can lead to large groundwater contaminant plumes extending miles from source areas. Low levels of PFBS have been detected in groundwater in Marinette County, the City of Madison, Town of Newton, La Crosse County and City of Rhinelander.
CSWAB’s petition responds to the recent release of an updated toxicity assessment by the U.S. Environmental Protection Agency (EPA). The biggest change is a new chronic Reference Dose (RfD) for PFBS which is approximately 70-fold LOWER than the current one. A reference dose is an estimate of a daily oral exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable risk of deleterious effects during a lifetime.
If approved by DNR, Wisconsin’s updated HAL of 3,000 ppt will still be higher (less protective) than neighboring states:
- In Michigan, the drinking water standard for PFBS of only 420 ppt.
- In Illinois, the current Health-Based Guidance Level for community water supplies is 2,100 ppt.
- Minnesota’s state health-based drinking water value is 2,000 ppt.
Stymied by partisan politics, Wisconsin is still years away from enforceable state standards for PFBS and other PFAS chemicals. In the interim, HALs remain critical health-based guideposts for DNR decisions such as who gets bottled water, whose drinking water well should be tested, which remedies are the most effective, what site-specific cleanup goals are appropriate, and how to best mitigate and prevent exposures.
PFBS is found in certain firefighting foams, but is also associated with dozens of other sources including chromium electroplater facilities, certain paper products and sludges, and water- and stain-repellent products and coatings.
Oral exposure to PFBS is associated with health effects on the thyroid, reproductive organs and tissues, developing fetus, and kidneys.