PFOS

abbreviation or noun

ˌpē-ˌef-ˌō-ˈes 

: a fluorinated sulfonic acid C₈HF₁₇O₃S that is a member of the PFAS group and that has been used especially for its water and stain resistance (as in carpeting and food packaging) and as a surfactant (as in firefighting foam and alkaline cleaners) : perfluorooctanesulfonic acid

By 2002, the primary U.S. manufacturer of PFOS had voluntarily phased out its production because it was found in human populations and in wildlife.

—National Association for Surface Finishing

In addition, private parties that clean up releases of PFOS and PFOA could now recover cleanup costs from potentially responsible parties.

—Stephanie Salmon

called also perfluorooctane sulfonate

Examples of PFOS in a Sentence

Recent Examples on the Web

Just before Trump left the White House in 2021, his EPA determined on January 19 that perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) need to be regulated in drinking water under the Safe Drinking Water Act. —Thomas G. Moukawsher, Newsweek, 6 Nov. 2024

For two chemicals, Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS), the Agency's ideal contamination level is zero. —John Timmer, Ars Technica, 10 Apr. 2024

The Environmental Protection Agency finalized an enforceable 4 parts per trillion (ppt) limit on perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in drinking water. —Democrat-Gazette Staff From Wire Reports, arkansasonline.com, 11 Apr. 2024

The participants in Lindhardt’s study had high levels of perfluorooctanesulfonic acid (PFOS) in their blood due to eating meat from cattle that fed in grassy areas where firefighters tested PFAS-containing foam. —Claire Bugos, Verywell Health, 25 Mar. 2024

Advertisement The Environmental Protection Agency plans to begin regulating several types of PFAS chemicals in drinking water and has proposed a strict limit of 4 parts per trillion for the chemicals perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). —Ian James, Los Angeles Times, 5 Aug. 2023

The Environmental Protection Agency plans to begin regulating several types of PFAS chemicals in drinking water and has proposed a strict limit of 4 parts per trillion for the chemicals perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). —Ian James, Los Angeles Times, 5 Aug. 2023

Word History

First Known Use

2002, in the meaning defined above