Human Health Toxicity Assessment for Perfluorobutane Sulfonic Acid (PFBS; CASRN 375-73-5) and Related Compound Potassium Perfluorobutane Sulfonate (CASRN 29420-49-3) (BOSC)
Presentation to the Board of Scientific Counselors Executive Meeting on PFAS to present the released final Human Health Toxicity Values for Perfluorobutane Sulfonic Acid (CASRN 375-73-5) and Related Compound Potassium Perfluorobutane Sulfonate (CASRN 29420-49-3). EPA released the toxicity assessment for perfluorobutane sulfonic acid (PFBS) and its potassium salt, potassium perfluorobutane sulfonate (K+PFBS) based on the Agency's analysis of the best available science on the health effects of these chemicals. The toxicity information and values included in this assessment can be used by EPA and other federal agencies, and state, tribal, and local communities, along with specific exposure and other relevant information, to determine, under appropriate regulations and statutes, if and when it is necessary to take action to address potential risk associated with human exposure to PFBS.
PFBS is a four-carbon PFAS that was developed as a replacement for perfluorooctane sulfonic acid (PFOS), a chemical that was voluntarily phased out by its U.S. manufacturers. PFBS has been identified in the environment and consumer products, including surface water, wastewater, drinking water, dust, carpeting and carpet cleaners, and floor wax. PFBS is persistent in the environment and mobile in groundwater and surface water.
High and medium confidence animal (rat and mouse) toxicity studies from oral exposure to PFBS and its potassium salt were available for acute, short-term, subchronic, and gestational exposure durations, as well as a two-generation reproductive toxicity study. A group of low and medium confidence human studies of PFBS exposure and health effects were identified, but their ability to inform conclusions was limited. Health outcomes evaluated across available studies included effects on the thyroid, reproductive organs and tissues, development, liver, lipids and lipoproteins, and kidneys following oral exposure to PFBS. Based on information across different sexes, lifestages, and durations of exposure, the thyroid appears to be particularly sensitive to oral PFBS exposure.
Impact/Purpose
EPA released the toxicity assessment for perfluorobutane sulfonic acid (PFBS) and its potassium salt, potassium perfluorobutane sulfonate (K+PFBS) based on the Agency's analysis of the best available science on the health effects of these chemicals. The toxicity information and values included in this assessment can be used by EPA and other federal agencies, and state, tribal, and local communities, along with specific exposure and other relevant information, to determine, under appropriate regulations and statutes, if and when it is necessary to take action to address potential risk associated with human exposure to PFBS.Citation
Owens, E. Human Health Toxicity Assessment for Perfluorobutane Sulfonic Acid (PFBS; CASRN 375-73-5) and Related Compound Potassium Perfluorobutane Sulfonate (CASRN 29420-49-3) (BOSC). Board of Scientific Counselors, Executive Meeting on PFAS, Cincinnati, OH, September 29 - 30, 2021.Download(s)
- PFAS BOSC PFBS OWENS 09152021_508 TAGGED.PDF (PDF) (NA pp, 436.6 KB, about PDF)