Perfluorobutanesulfonic acid (PFBS) is a chemical compound with a four carbon fluorocarbon chain and a sulfonic acid functional group. As an anion it functions as a stable fluorosurfactant because of the strength of carbon–fluorine bonds.
PFBS has served as a replacement for the persistent, toxic, and bioaccumulative perfluorooctanesulfonic acid (PFOS) in 3M's Scotchgard stain repellents since June 2003. PFBS has a much shorter half-life in people than PFOS (a little over one month vs. 5.4 years). While PFBS is expected to be persistent in the environment, multiple studies (that are not referenced in following reference) claim that PFBS is neither toxic nor bioaccumulative.
3M markets surfactant with PFBS in two fluorosurfactants.
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