Perfluoroalkyl and polyfluoroalkyl substances: current and future perspectives

Abstract

Environmental contextPerfluoroalkyl substances were recognised as global environmental pollutants 10 years ago. Although considerable advancements have been made in our understanding of the environmental distribution, fate and toxicity of perfluoroalkyl substances, several important issues remain to be resolved. This article identifies existing knowledge gaps that deserve further investigations to enable meaningful regulatory decisions. AbstractIt has been over a decade since perfluoroalkyl substances (PFASs) were discovered as global environmental contaminants. Considerable progress has been made in our understanding of the environmental fate and toxic effects of PFASs since then. Government regulations and voluntary emission reduction initiatives by industry have been effective in reducing environmental and human exposure to a major PFAS, perfluorooctane sulfonate (PFOS), in the United States and several other western countries. Although significant advances have been made in our understanding of the environmental chemistry of PFASs, considerable knowledge gaps still exist in several areas of environmental fate and risk assessments. Owing to their complex chemistry, involving existence of multiple precursors with significant numbers of structural isomers and mixtures of homologues, multiple degradation pathways and unique physicochemical properties, challenges remain in elucidating sources and environmental fate. In this overview, some of the knowledge gaps in PFASs’ research have been identified and suggestions for future research have been made.

Sorption of perfluoroalkyl substances in sewage sludge

“…Thus, they are widely used in many applications such as stain-and water-resistant textiles, food packaging, fire-extinguishing formulations, pesticides, paints, personal-care products and surfactants (Lau et al, 2007). In recent years, PFASs have attracted increasing public and scientific attention because of their high bioaccumulation potential, extreme persistence and toxic properties, such as their endocrine-disrupting activity and carcinogenesis (Kannan, 2011).…”

Spatial distribution of perfluoroalkyl acids in surface sediments of the German Bight, North Sea

“…Previous studies of PFAAs have raised considerable concern regarding their global distribution (Ahrens et al, 2009a;Butt et al, 2010;Cai et al, 2012;Kannan, 2011;Taniyasu et al, 2013;Yamashita et al, 2005), bioaccumulation and/or biotransformation in organisms and marine mammals, environmental degradation and potential toxicity (Giesy et al, 2010;Naile et al, 2010). In recent years, PFAAs have been reported in different environmental compartments such as air (Dreyer et al, 2009;Li et al, 2011), water (Ahrens, 2011;Benskin et al, 2012), sediment (Bao et al, 2010;Higgins et al, 2005;Lam et al, 2014;Pan et al, 2014;Theobald et al, 2012;Zhao et al, 2013), and in biota (Giesy and Kannan, 2001;Houde et al, 2006;Kannan et al, 2006).…”

Effects of elevated dissolved carbon dioxide and perfluorooctane sulfonic acid, given singly and in combination, on steroidogenic and biotransformation pathways of Atlantic cod

“…PFAS are synthetically produced and used in numerous consumer products and for industrial purposes because of their unique physiochemical properties (Buck et al, 2012;Paul et al, 2008). They are detected globally in the environment and biota, where perfluorooctane sulfonic acid (or sulfonate) (PFOS) is the most concentrated PFAS (Kannan, 2011) due to chemical persistency and tendency to bioaccumulate and biomagnify (Conder et al, 2008). PFOS exposure has been associated with numerous adverse health effects, including endocrine disruption (Lau et al, 2007;Oakes et al, 2005).…”