EPA Announces Stringent New Health Advisory Levels for Four PFAS Chemicals

In requesting information from its Scientific Advisory Board (SAB) on PFOA and PFOS last fall, the EPA signaled that it would seek to regulate these two chemicals at concentrations below the existing advisory levels of 70 parts per trillion (ppt). The revised advisory levels for these two substances confirm that suspicion and present new technical challenges in PFAS detection and treatment, as do the new advisory levels for PFBS and GenX.

Discussion
The federal Safe Drinking Water Act (SDWA) authorizes the EPA to issue health advisories to provide technical information for chemical contaminants in drinking water that can affect human health outcomes. Although health advisory levels are nonbinding guidelines, they inform or provide a technical basis for enforceable drinking water standards imposed by state regulators. Additionally, the advisory levels stand to influence governmental expectations at cleanup sites because, in the absence of codified cleanup standards, SDWA Maximum Contaminant Levels (MCLs) often serve as de facto cleanup standards, and for chemicals that are not the subject of an MCL, this function is fulfilled by health advisory levels.

The revised interim health advisory levels for PFOA and PFOS update the existing levels of 70 ppt, which were issued in 2016. Although some stakeholders advocated for the EPA to re-examine the risk assumptions that informed the 70 ppt threshold, the agency did not wait for a complete review from the SAB. Instead, the EPA moved to lower its recommended acceptable limits for PFOA and PFOS by three orders of magnitude. The new interim advisory level for PFOA is four parts per quadrillion (ppq), and the new advisory level for PFOS is 20 ppq. The advisory levels for PFOA and PFOS are “interim,” because EPA is working to finalize enforceable MCLs for these chemicals by 2023.

The EPA also issued final health advisory levels for PFBS and GenX (also known as HFPO-DA) for the first time, which are 2,000 ppt and 10 ppt, respectively. The issuance of advisory levels for these two chemicals is notable because both PFBS and GenX have potential applications in replacing PFOA and PFOS. This development indicates the potential for future regulation of PFOA and PFOS replacement chemicals and demonstrates that the EPA is taking a longer view toward regulating PFAS more broadly, not merely regulating the chemicals of current widespread concern.

The new health advisory levels are significantly lower than the cleanup levels most states have established for these four PFAS compounds in regulations in guidance. It will be critical to monitor how state regulators respond to the EPA’s new guidelines.

Concerns Regarding Effective Monitoring, Treatment
Although the new advisory levels for PFOA and PFOS theoretically allow for safe acceptable levels of exposure to these chemicals in drinking water, the EPA has acknowledged that the current test methods available to laboratories cannot detect or accurately measure PFAS chemicals at concentrations as low as four ppq. For now, the EPA recommends testing for PFOA and PFOS at the analytical detection limit of four ppt. Without improvements in measurement technologies, PFAS treatment and remediation will likely become even more challenging as some state regulators move to follow the EPA’s recommendations and lower their PFAS thresholds below currently detectable levels.

It is also uncertain whether existing methods of PFAS treatment or remediation technologies can achieve such low concentrations. The EPA maintains that granular activated carbon (GAC), widely recognized as the most effective PFAS remedial treatment, can remove 100% of PFOA and PFOS from groundwater, subject to various site-specific factors. However, industry tends to characterize the optimal efficiency of this treatment method at 95% or 99%. It remains to be seen whether other treatment methods, such as source water replacement, water blending and reverse osmosis treatment will remain viable options if regulators insist on attainment of the health advisory levels.

New federal funding can aid the development of improved measurement and remedial technologies. The Bipartisan Infrastructure Law of 2021 authorized $5 billion in grants to states and localities for technical assistance, water quality testing, contractor training and installation of centralized treatment and technology systems to help remediate PFAS contamination. As part of its recent announcement, the EPA is making $1 billion of this funding available and will be proactively reaching out to states and territories with information on how to apply for PFAS grants.

Military-Related PFAS Concerns
The accelerating pace of PFAS regulation stands to place stress on parties engaged in cleaning up PFAS at various remediation sites. Military installations are among the most important PFAS cleanup sites likely to be affected by these developments. The primary use of PFAS on military installations is through aqueous firefighting foam (AFFF). Although the Department of Defense (DoD) is required to switch to PFAS-free firefighting alternatives by October 2023, the DoD has not yet identified replacement materials that meet existing safety and performance requirements. According to a June 2021 Government Accountability Office (GAO) report, 687 military installations have known or suspected releases of PFAS. The DoD estimates that PFAS costs incurred after Fiscal Year 2021 will total at least $2.1 billion, in addition to $1.1 billion already incurred. However, the revised health advisory levels for PFAS may lead to more stringent treatment requirements, and the DoD’s liability could greatly exceed current estimates.

Conclusion
The EPA’s issuance of new health advisory levels for four PFAS chemicals represents a significant development in the agency’s regulation of PFAS. The new health advisories could lead to expanded and costlier cleanup requirements at PFAS contamination sites and to more litigation addressing liability for the costs of cleanup and claims regarding exposure to PFAS. Furthermore, they stand to take on heightened significance if they serve as the basis for the EPA’s anticipated issuance of MCLs for PFOA and PFOS, especially considering the promised designation of these two PFAS as CERCLA hazardous substances.

Pillsbury environmental attorneys have extensive experience dealing with PFAS, including assisting companies in responding to governmental information requests and subpoenas regarding their products and sites, developing PFAS-specific investigation and remedial plans, and working with the DoD regarding PFAS cleanups.

The authors would like to thank summer law clerk Steve R. Brenner for his contributions to this post.