Thought Leadership

Recent Actions Signal Significant Chemical Risk Assessment Changes at EPA

Client Updates

Companies should note two new EPA decisions on chemical risk assessment which together signal that new leadership at the U.S. Environmental Protection Agency (EPA) will take some different approaches to chemical risk assessments and analysis of underlying scientific studies.

On February 16, EPA announced that, under the new administration’s memorandum on scientific integrity and evidence based policy making, EPA “will refine its approach to selecting and reviewing the scientific studies that are used to inform Toxic Substances Control Act (TSCA) chemical risk evaluations (systematic review).” On February 9, EPA removed from its website the final toxicity assessment for perfluorobutanesulfonic acid (PFBS), a PFAS compound, stating the final version eroded “the trust that the American public has in EPA, the quality of our science, and our ability to protect their health and the environment.” 

In these early efforts, EPA is leaning on new “Executive Orders and other directives provided by the Biden-Harris Administration to ensure that all agency actions meet statutory obligations, [are] guided by the best available science, ensure the integrity of Federal decision-making, and protect human health and the environment.” At least initially, the chemical manufacturing and chemical user communities should remain vigilant in monitoring EPA’s new directions and actions to ensure that the pursuit of the best available science follows the applicable laws and regulations and does not result in excessive layers of scientific conservatism.

EPA’s February 16 commitment to update its 2018 systematic review approach to chemical literature assessment, made within hours of the National Academies of Sciences (NAS) release of a related peer-review, was of little surprise – EPA was already well into the updating process. Worth noting, however, is EPA’s response to the NAS recommendations, particularly that EPA will incorporate “approaches from the Integrated Risk Information System (IRIS) Program.” The IRIS program is long acknowledged as highly conservative in its development of chemical toxicity assessments.

The final PFBS assessment removed February 9 from EPA’s website included a range of toxicity values instead of a single number to account for uncertainties in the PFBS literature and science. When withdrawing the assessment, EPA expressed concern with toxicity ranges because they can result in companies picking and choosing among numbers. A reasonable expectation is that any PFBS assessment re-posted by EPA will include a single toxicity value. The inherent compounded uncertainty could affect air and water quality permit limits or cleanup requirements.

Chemical manufacturers and chemical users should keep a watchful eye on further adjustments and changes to EPA’s chemical assessment policy. These changes, while subtle, when combined will impact chemical manufacturers and chemical users. EPA is working on 10 risk management rulemakings under TSCA and is early in risk assessment for 20 more chemicals, including invoicing the responsible parties. As such, there is no shortage of opportunities to engage in EPA’s chemical assessment activities, and no time to lose.

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