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The type of PFAS remediation technology selected is often a reflection of the PFAS contamination levels and the PFAS signature (i.e. the combination of short- and long-chain PFAS substances present) in conjunction with the site-specific water chemistry and cross contaminants present in the liquid stream.
Early 2018 Department of Health & Human Services's Agency for Toxic Substances and Disease Registry (ATSDR) was about to publish its assessment of PFAS chemicals, with a focus on two specific chemicals from the PFAS class—PFOA and PFOS—that have "contaminated water supplies near military bases, chemical plants and other sites from New York ...
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.
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]
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 .
Perfluorooctanesulfonamide (PFOSA) is a synthetic organofluorine compound.It is a fluorocarbon derivative and a perfluorinated compound, having an eight-carbon chain and a terminal sulfonamide functional group.
Perfluoroalkanes are very stable because of the strength of the carbon–fluorine bond, one of the strongest in organic chemistry. [4] Its strength is a result of the electronegativity of fluorine imparting partial ionic character through partial charges on the carbon and fluorine atoms, which shorten and strengthen the bond (compared to carbon-hydrogen bonds) through favorable covalent ...
In March 2019, Khanna was one of 14 members of the House to cosponsor the PFAS Detection Act, legislation intended to provide $45 million (~$52.9 million in 2023) to the U.S. Geological Survey for the purpose of developing advanced technologies that can detect PFAS and afterward conduct nationwide sampling for PFAS in the environment. [61]