With the release of the final toxicity assessment for PFBS, EPA completes yet another priority action identified in EPA’s Per-and Polyfluoroalkyl Substances (PFAS) Action Plan. PFBS is a member of PFAS, a very large diverse class of synthetic chemicals, including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS).
In the early 2000s, concerns grew over the environmental persistence, long half-lives in humans, and bioaccumulation potential of longer chain PFAS, in particular PFOA and PFOS. As a result, shorter chain PFAS such as PFBS were developed and integrated into various consumer products and applications, as this compound has the desired properties and characteristics associated with this class of compounds with faster elimination from the body than PFOA and PFOS.You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.
- Pre-publication Notice: Docket EPA-HQ-ORD-2021-0035 (PDF)(5 pp, 911 K, January 19, 2021)
Human Health Toxicity Values for Perfluorobutane Sulfonic Acid and Related Compound Potassium Perfluorobutane Sulfonate (PDF)(171 pp, 7 MB,
January 19, 2021)
The information in the PFBS toxicity assessment may be used by federal partners, states, tribes, and local communities, along with specific exposure and other relevant information to determine, under the appropriate regulations and statutes, if and when it is necessary to take action to address potential risks associated with human exposures to PFBS.
Memo: Toxicity Assessment for PFBS (PDF)(5 pp, 213 K,
January 15, 2021)
OCSPP provided this memo to advance cross-office consistency and coordination. OCSPP was an important part of the Agency workgroup on the Assessment. The memo identifies key considerations regarding the application of a database deficiency uncertainty factor for both chronic and subchronic toxicity, taking into account data needs.