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The United States Environmental Protection Agency defines PFAS in the Drinking Water Contaminant Candidate List 5 as substances that contain "at least one of the following three structures: R−CF 2 −CF(R')R", where both the −CF 2 − and −CF− moieties are saturated carbons, and none of the R groups can be hydrogen; R−CF 2 −O−CF 2 ...
Remediation of per- and polyfluoroalkyl substances refers to the destruction or removal of per- and polyfluoroalkyl substances (PFASs) from the environment. PFASs are a group of synthetic organofluorine compounds, used in diverse products such as non-stick cookware and firefighting foams, that have attracted great concern as persistent organic pollutants.
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]
Long-chain PFAS chemicals perfluorooctane sulfonic acid, or PFOS, and perfluorooctanoic acid, or PFOA, are among the most studied of the nearly 15,000 types of PFAS used by industry.
They’ve said the EPA’s $1.5 billion annual cost estimate is too low, water bills for consumers will go up and the health benefits of the rule aren’t big enough, especially at low PFAS ...
These chemical bonds also prevent natural processes from breaking PFOA down, hence the name: “Forever chemicals.” Similar compounds soon emerged, such as 3M’s PFOS, the magic behind the ...
The CompTox Chemicals Dashboard is a freely accessible online database created and maintained by the U.S. Environmental Protection Agency (EPA). The database provides access to multiple types of data including physicochemical properties , environmental fate and transport, exposure, usage, in vivo toxicity, and in vitro bioassay.
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.