EPA Releases Human Health Toxicity Report for PFBS, a PFAS Chemical

The U.S. EPA has released a report on Human Health Toxicity Values for Perfluorobutane Sulfonic Acid (PFBS) and Related Compound Potassium Perfluorobutane Sulfonate (CAS #29420-49-3). PFBS is a member of a larger group of per- and polyfluoroalkyl substances (PFAS). This assessment is part of EPA’s efforts to increase the amount of research and information that is publicly available on chemicals in the PFAS family. It was developed by the U.S. EPA’s Office of Research and Development (ORD) Center for Public Health and Environmental Assessment (CPHEA).

PFBS, known as a replacement chemical for PFOS, has been detected in consumer products and the environment, including carpeting, cleaners, floor wax, wastewater, surface water, and drinking water. Health effects that are associated with PFBS include effects on the thyroid, reproductive organs and tissues, and kidneys. Studies have also demonstrated health effects on a developing fetus.


PFBS is persistent in the environment and mobile in surface water and groundwater. The PFBS assessment provides toxicity values and data about the adverse effects of the chemical and the evidence on which the value is based, including the strengths and limitations of the data. The assessment provides evaluations and conclusions drawn from publicly available information on the toxicity of PFBS.

According to the EPA, the PFBS toxicity assessment is one the primary goals of the PFAS Action Plan and provides qualitative and quantitative toxicity data that can be used by federal partners, states, tribes, and local communities, along with specific exposure and other relevant data to determine, under the appropriate regulations and statutes, if and when it is necessary to take action to address risk associated with human exposure to PFAS.

Merit Laboratories is a leading national PFAS environmental laboratory, analyzing drinking water, soil, wastewater, groundwater, and other sample matrices, including biosolids and sludge. Analytical methods performed by Merit for PFAS include drinking water by EPA 533, EPA 537.1, and EPA 537 rev. 1.1, biosolids by ASTM D7968-17 with Isotopic Dilution, and soil, wastewater, groundwater, and surface water by ASTM D7979-19 with Isotopic Dilution and ASTM D7968-17.