The protocol presents the methods for conducting the systematic reviews and dose-response analyses for development of a draft IRIS assessment for five per- and polyfluoroalkyl substances (PFAS) assessments including: perfluorodecanoic acid (PFDA; CASRN 335-76-2), perfluorononanoic acid (PFNA; CASRN 375-24-4), perfluorohexanoic acid (PFHxA, CASRN 307-24-4), perfluorohexanesulfonic acid (PFHxS, CASRN 355-46-4), and perfluorobutanoic acid (PFBA, CASRN 375 22 4), and their related salts which are all members of the group per and polyfluoroalkyl substances (PFAS). These five toxicity assessments are being developed according to the scope and methods outlined in this protocol built upon several other PFAS assessments that have already been developed by the EPA. It includes a summary of why these specific PFAS were prioritized for evaluation, description of the objectives and specific aims of the assessments, draft PECO (Populations, Exposures, Comparators, and Outcomes) criteria, and identification of key areas of scientific complexity.

U.S. EPA. Systematic Review Protocol for the PFAS IRIS Assessments. U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-19/050, 2019.

Andrew D. Kraft,  Ph:  202-564-0286,  Email: kraft.andrew@epa.gov

James W. Avery,  Ph:  202-564-1494,  Email: avery.james@epa.gov

Date	Description
Nov 2019	EPA released the Systematic Review Protocol for the PFAS IRIS Assessments (Preliminary Assessment Materials). [Federal Register Notice Nov 8, 2019]
Jul 2020	EPA released an update to the Systematic Review Protocol for the PFBA, PFHxA, PFHxS, PFNA, and PFDA IRIS Assessments in response to public comments.

Concluding the public comment period, the IRIS Program will use the comments received and the methods outlined in the protocol for conducting the systematic review to develop 5 individual PFAS IRIS draft assessments.

In addition to being released on the EPA website, the protocol will be published in the Zenodo data repository (https://zenodo.org/).

This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.

• An Update to the Systematic Review Protocol for the PFBA, Pfhxa, Pfhxs, PFNA, and PFDA IRIS Assessments (July 2020) (PDF)  (203 pp, 3 MB, about PDF)
• An Update to the Systematic Review Protocol Appendix A PFBA (Interagency Review Draft, Oct 2020) (PDF)  (203 pp, 3 MB, about PDF)
• Errata Sheet (Sep 2020) Pertaining to the PFBA Protocol Appendix A Update (PDF)  (1 pp, 108 KB, about PDF)
• Systematic Review Protocol for the PFBA, Pfhxa, Pfhxs, PFNA, and PFDA IRIS Assessments (PDF)  (197 pp, 3 MB, about PDF)

• Learn More About Per-and Polyfluoroalkyl Substances
• EPA's PFAS Action Plan
• Risk Management for Per-and Polyfluoroalkyl Substances (PFAS) Under TSCA
• Genx and PFBS Draft Toxicity Assessments
• Systematic Review Protocol for the Perfluorobutanoic Acid (PFBA) IRIS Assessment
• Systematic Review Protocol for the Perfluorodecanoic Acid (PFDA) IRIS Assessment
• Systematic Review Protocol for the Perfluorononanoic Acid (PFNA) IRIS Assessment
• Systematic Review Protocol for the Perfluorohexanoic Acid (Pfhxa) IRIS Assessment
• Systematic Review Protocol for the Perfluorohexanesulfonate (Pfhxs) IRIS Assessment

• List of HERO Project Pages for PFAS

• FR Notice: Nov 8, 2019

Comments on the assessment may be submitted and reviewed using the Docket ID EPA-HQ-ORD-2019-0275