Perfluorobutanesulfonic acid (PFBS) is a chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 with a four carbon

Carbon

Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

 fluorocarbon

Fluorocarbon

Fluorocarbons, sometimes referred to as perfluorocarbons or PFCs, are organofluorine compounds that contain only carbon and fluorine bonded together in strong carbon–fluorine bonds. Fluoroalkanes that contain only single bonds are more chemically and thermally stable than alkanes...

 chain and a sulfonic acid

Sulfonic acid

Sulfonic acid usually refers to a member of the class of organosulfur compounds with the general formula RS2–OH, where R is an alkyl or aryl. The formal part of acid, HS2–OH, are formally derivatives of the "parent" inorganic compound with the formula HSO2.-Preparation:Sulfonic acid is...

 functional group

Functional group

In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction regardless of the size of the molecule it is a part of...

. As an anion it functions as a stable fluorosurfactant

Fluorosurfactant

Fluorosurfactants, or fluorinated surfactants, are synthetic organofluorine chemical compounds that have multiple fluorine atoms. They can be polyfluorinated or fluorocarbon-based . As surfactants, they are more effective at lowering the surface tension of water than comparable hydrocarbon...

 because of the strength of carbon–fluorine bond

Carbon–fluorine bond

The carbon–fluorine bond is a bond between carbon and fluorine that is a component of all organofluorine compounds. It is the strongest single bond in organic chemistry—and relatively short—due to its partial ionic character. The bond also strengthens and shortens as more fluorines are...

s.

PFBS has served as a replacement for the persistent, toxic, and bioaccumulative perfluorooctanesulfonic acid (PFOS) in 3M

3M

3M Company , formerly known as the Minnesota Mining and Manufacturing Company, is an American multinational conglomerate corporation based in Maplewood, Minnesota, United States....

's Scotchgard

Scotchgard

Scotchgard is a 3M brand of products used to protect fabric, furniture, and carpets from stains.The original formula for Scotchgard was discovered accidentally in 1952 by 3M chemists Patsy Sherman and Samuel Smith...

 stain repellents since June 2003. PFBS has a much shorter half-life

Half-life

Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...

 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 indicate PFBS is neither toxic nor bioaccumulative.

3M markets surfactant

Surfactant

Surfactants are compounds that lower the surface tension of a liquid, the interfacial tension between two liquids, or that between a liquid and a solid...

with PFBS in two fluorosurfactants.