By Jane C. Luxton and William J. Walsh, Partners in the Washington, DC office of Lewis Brisbois.

Per- and polyfluorinated alkyl substances (“PFAS”) are a group of 3,000 to 5,000 chemical compounds invented in the 1940s and long valued for water, grease, and heat resistant properties that proved highly useful in a large number of consumer products.1  Those products include nonstick cookware, water-repellent outerwear, food containers, carpets and textiles, fire-fighting foam, cleaning solutions, paints and coatings, and many others.  In recent years, concern over potential human-health impacts of PFAS chemicals has grown, thanks in large part to their persistence and widespread dispersion in the environment.  Scientists have conducted assessments for some PFAS compounds, most notably perflourooctanoic acid (“PFOA”) and perfluorooctane sulfonate (“PFOS”), but only a few compounds have received extensive study and little scientific consensus exists as to specific health effects.2  As 2020 begins, vigorous action to address PFAS contamination is underway on multiple fronts:  proposed legislation, federal and state regulation, and expansive litigation.3  This Legal Backgrounder focuses on the widening scope of PFAS litigation, which initially targeted PFOA and PFOS chemical producers, but increasingly is targeting downstream manufacturers, processors, and users of PFAS compounds, alleging liability for far-reaching groundwater and legacy contamination.