On June 15, 2022, the United States Environmental Protection Agency (EPA) released drinking water health advisories  for certain per- and polyfluoroalkyl substances (PFAS), resulting in the establishment of:
- Near zero updated interim advisory levels for Perfluorooctanoic acid (PFOA) and Perfluorooctane sulfonic acid (PFOS) that are not only orders of magnitude below previously established levels, but that are also below detectable levels and, notably, were issued in advance of completion of peer review by EPA’s Science Advisory Board (SAB); and
- Newly issued final advisories at low levels for GenX and PFBS chemicals that have been used as replacement chemicals for PFOA and PFOS.
While these health advisories are not binding or enforceable, their issuance poses new compliance challenges with far-reaching implications for a broad spectrum of the regulated community and affected stakeholders. These include:
- States are now faced with determining whether to update drinking water standards based on the new advisory levels, as some have done with prior EPA PFOA and PFOS health advisories.
- Municipalities and drinking water utilities charged with monitoring and treatment of PFAS in drinking water must determine appropriate levels of testing and treatment for PFOA and PFOS, as well as how to communicate risk to their customers.
- Private parties and government entities cleaning up PFAS at contaminated sites must now determine whether to revisit preliminary remediation goals where prior PFOA and PFOS drinking water health advisories have been used, creating the potential for disruption, added complexity, and costs if site-specific cleanup levels are drastically reduced. 
- Manufacturers of products that may contain these chemicals may now face increased scrutiny and litigation risks, including for the disposal of returned or obsolete products with low levels of these PFAS.
Under the Safe Drinking Water Act, for contaminants that are not currently subject to an enforceable national primary drinking water regulation, EPA is authorized to provide drinking water health advisories to inform the public of the concentration levels of these contaminants in drinking water that are not expected to cause adverse health effects over specified exposure durations. EPA issues a final health advisory upon completion of a final health effects assessment and an interim health advisory when a contaminant’s health effects assessment has not been finalized but the agency considers that there is a pressing need to provide information to public health officials. While these concentration levels are advisory, they influence a number of federal and state policies and have important implications for the regulated community.
Updated and New Advisories
In its June 15 release, EPA established the following interim updated lifetime drinking water health advisories:
- Perfluorooctanoic acid (PFOA): 0.004 ppt.
- Perfluorooctane sulfonic acid (PFOS): 0.02 ppt.
These levels are orders of magnitude below the 70 ppt levels previously established by EPA for PFOA and PFOS in 2016, and suggest EPA may be moving towards concluding that there is no safe level of these substances in drinking water. In addition, these levels are also far below the concentration limits for PFOA and PFOS included in regulations adopted in multiple states that were considerably lower than EPA’s former 70 ppt advisory level, such as Michigan (8 ppt maximum contaminant level for PFOA) and New Hampshire (15 ppt maximum contaminant level for PFOS).
In its release, EPA notes that it is basing the updated PFOA and PFOS health advisories on suppression of vaccine response (decreased serum antibody concentrations) in children and that cancer analyses are ongoing for both PFOA and PFOS.  EPA has explained that it is issuing these interim health advisories consistent with its responsibility to protect public health in light of new scientific information, but acknowledges that the advisories are based on draft health assessments for PFOA and PFOS that are not final and are currently undergoing review by the SAB. 
EPA further acknowledges that “[b]ased on current methods, the health advisory levels for PFOA and PFOS are below the level of both detection (determining whether or not a substance is present) and quantitation (the ability to reliably determine how much of a substance is present). This means that it is possible for PFOA or PFOS to be present in drinking water at levels that exceed health advisories even if testing indicates no level of these chemicals” (emphasis added).  While EPA has underscored that it plans to respond to the SAB’s comments as it develops Maximum Contaminant Level Goals (MCLGs) later this year, it has also signaled that “[b]ecause the available health effects data indicate a number of different adverse impacts resulting from exposure to very low levels of PFOA or PFOS, the health-based water values (health advisories and MCLGs) are likely to remain below detection limit” (emphasis added). 
EPA also finalized the lifetime health advisories for the following PFAS substances:
- Hexafluoropropylene oxide (HFPO) dimer acid and its ammonium salt (referred to as GenX chemicals): 10 ppt. EPA set this level based on animal toxicity studies that reported health effects in the liver, kidney, immune system, development, and cancer. EPA’s basis for the final health advisory for GenX is a liver effect. EPA notes that, while there is “suggestive evidence” of carcinogenic potential of oral exposure to GenX chemicals, data are “insufficient” at this time to derive a cancer risk concentration in water for GenX.
- Perfluorobutane sulfonic acid and its related compound potassium perfluorobutane sulfonate (referred to as PFBS): 2,000 ppt. EPA set this level based on animal toxicity studies that reported health effects in the thyroid, reproductive system, development, and kidney. EPA’s basis for the final health advisory for PFBS is a thyroid effect. EPA notes that it could not evaluate potential cancer effects because there are no known studies evaluating cancer effects from PFBS exposure. 
According to EPA, “the health advisory levels for GenX chemicals and PFBS are above the detection and quantitation levels, and therefore can be reliably measured using specified analytical methods in appropriate laboratory settings.” 
These PFAS health advisories are part of EPA’s broader efforts to address PFAS as outlined in its PFAS Strategic Roadmap: EPA’s Commitment to Action 2021-2024 (see our recent coverage of EPA’s Roadmap). In the PFAS Strategic Roadmap, EPA signaled that it expected to issue final drinking water health advisories for GenX and PFBS in the spring of 2022, which it has now done. EPA also noted that, while it had regulated more than 90 drinking water contaminants, it had not established national drinking water regulations for any PFAS. Assuming that EPA’s anticipated schedule of fall of 2022 for a proposed rule and fall of 2023 for a final rule is met, the interim drinking water health advisories for PFOA and PFOS would be of short duration. Based on the EPA comments noted above, however, it has signaled that extremely low values, including potentially those below the detection limit, may remain in the MCLGs.
Bipartisan Infrastructure Law Funding
Following the release of the health advisories, and in an effort to defray associated costs, EPA also announced  that states could apply for $1 billion in grant funding (the first of $5 billion) as part of President Biden’s Bipartisan Infrastructure Law to address PFAS in drinking water, specifically in small and disadvantaged “frontline” communities. States and territories can apply for these grants until August 15, 2022.
Future Actions to Address PFAS
EPA is expected to take additional actions to address PFAS in the near future. For instance, the White House has recently stated that “[i]n the coming weeks, EPA will issue a proposed rule to designate PFOA and PFOS as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), which will enable EPA to leverage the full range of Superfund authorities, including requiring reporting of PFOA and PFOS releases and to hold polluters accountable by recovering cleanup costs.”  We have previously discussed the vast implications and potential costs of this unprecedented CERCLA regulatory action, which now have the potential to be further exacerbated. Notably, if PFOA and PFOS are listed as hazardous substances under CERCLA, EPA’s exceedingly low health advisories may drive site-specific cleanup standards for PFOA and PFOS that present challenges with detection methods and treatment technologies.
We will continue to monitor and report on these future PFAS developments. It will be important for affected stakeholders to actively engage with EPA on the adoption of science-based and technically feasible drinking water standards.
 87 Fed. Reg. 36,848 (June 21, 2022).
 The Department of Defense is facing major liabilities at PFAS sites, particularly airports that have a history of discharging the fire-fighting foam known as “AFFF” that is known to contain PFOS and PFOA. See, e.g., Department of Defense PFAS Task Force Progress Report (March 2020). See also David Vergun, DOD’s PFAS Public Outreach Focuses on Cleanup Process, PFAS-Free Firefighting Solutions, Officials Say, DOD News, U.S. Department of Defense (October 21, 2021).
 87 Fed. Reg. at 36,849.
 87 Fed. Reg. at 36,849.