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It is commonly referred to as the main harmful PFAS chemical and PFOA is responsible for many of the negative health effects commonly associated with PFAS. Per- and polyfluoroalkyl substances are a group of synthetic organofluorine chemical compounds that have multiple fluorine atoms attached to an alkyl chain. Different organizations use ...
Perfluorosulfonic acids (PFSAs) are chemical compounds of the formula C n F (2n+1) SO 3 H and thus belong to the family of perfluorinated and polyfluorinated alkyl compounds (PFASs). The simplest example of a perfluorosulfonic acid is the trifluoromethanesulfonic acid .
Perfluorooctanesulfonic acid (PFOS) (conjugate base perfluorooctanesulfonate) is a chemical compound having an eight-carbon fluorocarbon chain and a sulfonic acid functional group, and thus it is a perfluorosulfonic acid and a perfluoroalkyl substance (PFAS). It is an anthropogenic (man-made) fluorosurfactant, now regarded as a global pollutant.
Trifluoroacetic acid is a widely employed acid, used for example in the synthesis of peptides.Its esters are useful in analytical chemistry. Longer-chain perfluoroalkyl carboxylic acids, e.g. with five to nine carbons, are useful fluorosurfactants and emulsifiers used in the production of polytetrafluoroethylene (Teflon) and related fluoropolymers.
Story at a glance A group of potentially harmful chemicals called per- and polyfluoroalkyl substances (PFAS) have repeatedly cropped up in headlines. But the sheer number of chemicals in this ...
Fluorosurfactants (PFAS) reduce surface tension by concentrating at the liquid-air interface due to the lipophobicity of polyfluorocarbons. Chlorofluorocarbons are also perfluorinated compounds, many of which were formerly used as refrigerants ( Freon ) until they were implicated in ozone degradation .
A new EU drinking water directive issued in 2020 adopted PFAS limit values. The limit values are 0.1 μg/L for the sum of 20 PFASs including PFHxS, and 0.5 μg/L for the sum of all PFASs. This directive is binding for all EU member nations. It is a minimum directive, and member states can elect to adopt stricter regulations. [19]
Feb. 3—SANTA FE — The U.S. Environmental Protection Agency on Thursday announced two proposed rules "to ensure that certain per- and polyfluoroalkyl substances (PFAS), also known as 'forever ...