June 27, 2022
EPA lowers PFOA & PFOS health advisories, creates new ones for PFBS & GenX
On June 15, the U.S. Environmental Protection Agency released new and updated drinking water health advisories for select per- and polyfluoroalkyl substances (PFAS). EPA issued final health advisories of 2,000 parts per trillion (ppt) for perfluorobutane sulfonic acid and its potassium salt (PFBS) and 10 ppt for hexafluoropropylene oxide (HFPO) dimer acid and its ammonium salt ("GenX" chemicals). EPA also issued updated interim health advisories of 0.004 and 0.02 ppt for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), respectively.
This announcement marks another step in EPA's PFAS Strategic Roadmap, a guide to actions the agency intends to take to address PFAS. In tandem, EPA invited states and territories to apply for $1 billion in grant funding under last year's major infrastructure legislation to address PFAS and other emerging contaminants in drinking water.
Final health advisories issued for PFBS and GenX chemicals are based on EPA's 2021 final toxicity assessments for these specific PFAS. The updated PFOA and PFOS health advisories are based on new studies and draft toxicity values from EPA's 2021 draft PFOA and PFOS health effects documents and replace the 2016 health advisory level of 70 ppt for PFOA and PFOS combined. EPA is developing a proposed National Drinking Water Regulation to develop maximum contaminant levels (MCLs) for PFOA and PFOS for publication by the end of 2022 and anticipates finalizing the rule by the end of 2023.
Health advisory values represent substance concentrations in drinking water at which adverse health effects are not anticipated over specific exposure durations. They are non-regulatory and non-enforceable; however, states and other entities often use these values in decision-making. For example, Montana adopted EPA's 2016 health advisory for PFOA and PFOS as a numeric water quality standard for groundwater, and EPA recommended its use as the preliminary remediation goal for Superfund sites where contaminated groundwater is a current or potential drinking water source.
The updated 2022 interim health advisories for PFOS and PFOA are 200 and 1,000 times, respectively, below the concentrations that can be quantified using EPA-approved analytical methods. The health advisories were established based on potential health impacts and do not consider the feasibility of available treatment technologies to meet these levels. Because treatment feasibility will be considered in the development of MCLs for these chemicals, MCLs may be established at higher concentrations than these new health advisories. These factors can complicate the process of designing and implementing treatment systems to remove these compounds from contaminated water sources and communicating analytical results to the public.
How Exponent Can Help
Exponent's expert consultants in regulatory compliance, contaminant fate and transport, and analytical chemistry help clients navigate the current regulatory landscape and manage their ongoing environmental liabilities. Our multi-disciplinary team of scientists and engineers considers both state and federal regulations when developing strategic solutions for our clients' needs. Exponent can help with selecting appropriate methods and laboratories for PFAS analyses based on the intended use of the data; source identification, chemical fingerprinting, and fate and transport analyses of PFAS in the environment; reviewing and commenting on proposed state and federal regulations for PFAS compounds; and providing technical support for strategic business decisions and communications.