As part of the U.S. Environmental Protection Agency’s (USEPA) extensive efforts to help communities address per- and polyfluoroalkyl substances (PFAS) under the PFAS Action Plan, the USEPA released the Systematic Review Protocol for five PFAS toxicity assessments for a 45-day public comment period. The assessments are being developed under the Integrated Risk Information System (IRIS) Program.
The Systematic Review Protocol is not a toxicity assessment, instead it describes how the five IRIS assessments will be conducted, including specific procedures and approaches. The five PFAS the USEPA is focusing on under this protocol are: perfluorodecanoic acid (PFDA), perfluorononanoic acid (PFNA), perfluorohexanoic acid (PFHxA), perfluorohexanesulfonate (PFHxS), and perfluorobutanoic acid (PFBA).
Though the Systematic Review Protocol summarizes the methods in one document, there will be five separate IRIS assessments. The IRIS assessments will identify the potential human health effects from exposure to each assessed PFAS and will develop toxicity values, as supported by the available evidence.
Depending on data availability, the assessments will evaluate both cancer and noncancer effects, including potential effects on the endocrine, hepatic, urinary, immune, developmental, and reproductive systems. Systematic review protocols are released early in the IRIS assessment development process as an added effort to increase transparency, and to allow the public and stakeholders to understand how an assessment will be conducted. This includes defining what procedures will be used and describing any anticipated areas of scientific complexity that will be important to address in the toxicity assessment.
This Systematic Review Protocol will be available for public comment via the Federal Register until December 23, 2019. Public input received on the protocol is considered during preparation of the draft assessments and any adjustments made to the protocol will be reflected in an updated version released in conjunction with the public release of the draft assessments.
PFAS are a large group of manmade chemicals composed of one or more carbon atoms on which all hydrogen substituents have been replaced with fluorine atoms. The compounds are used in consumer products and industrial processes. PFAS are resistant to heat, oils, stains, grease, and water, which contribute to their persistence in the environment.