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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 .
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.
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.
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]
Perfluoropropanesulfonic acid (PFPrS) is a PFAS chemical compound having a three-carbon fluorocarbon chain and a sulfonic acid functional group. It has been used within the manufacturing process of aqueous film forming foam (AFFF).
Perfluorobutanesulfonic acid (PFBS) is a PFAS chemical compound having a four-carbon fluorocarbon chain and a sulfonic acid functional group. It is stable and unreactive because of the strength of carbon–fluorine bonds. It can occur in the form of a colorless liquid or a corrosive solid. [1]