Legacy and Emerging Per- and Polyfluoroalkyl Substances: Analytical Techniques, Environmental Fate, and Health Effects

Abstract

Due to their unique chemical properties, per- and polyfluoroalkyl substances (PFAS) have been used extensively as industrial surfactants and processing aids. While several types of PFAS have been voluntarily phased out by their manufacturers, these chemicals continue to be of ecological and public health concern due to their persistence in the environment and their presence in living organisms. Moreover, while the compounds referred to as “legacy” PFAS remain in the environment, alternative compounds have emerged as replacements for their legacy predecessors and are now detected in numerous matrices. In this review, we discuss the historical uses of PFAS, recent advances in analytical techniques for analysis of these compounds, and the fate of PFAS in the environment. In addition, we evaluate current biomonitoring studies of human exposure to legacy and emerging PFAS and examine the associations of PFAS exposure with human health impacts, including cancer- and non-cancer-related outcomes. Special focus is given to short-chain perfluoroalkyl acids (PFAAs) and ether-substituted, polyfluoroalkyl alternatives including hexafluoropropylene oxide dimer acid (HFPO-DA; tradename GenX), 4,8-dioxa-3H-perfluorononanoic acid (DONA), and 6:2 chlorinated polyfluoroethersulfonic acid (6:2 Cl-PFESA; tradename F-53B).

Bioaccumulation, Biodistribution, Toxicology and Biomonitoring of Organofluorine Compounds in Aquatic Organisms

“…The effects of perfluoroalkylic emerging pollutants are worrying since they involve the functionality of several organs and are generally more severe with increasing time of exposure and concentration of the contaminant [8, 26,38,121]. Compared to the effects of PFCs studied in humans, the biomolecular effects shown in aquatic organisms are more subject to controlled laboratory conditions, derive from a variety of experiments, and thus represent a wider panorama of possible consequences to PFCs exposure [16,17,87,[122][123][124][125][126][127][128][129][130][131][132].…”

“…For the determination of PFAS in aquatic organisms, several studies have been carried out and more sensitive, rapid, and robust extraction and analytical methods have been recently developed [20][21][22][23][24]. Moreover, literature on PFAS environmental impact is continuously foraged by new research on their bioconcentration [25], health effects [26], human exposure, and legal regulation [8]. The purpose of this review is to provide an organized overview of the impact of PFAS, with a specific focus on aquatic biota, evaluated through studies on biomonitoring, determination of contamination and biodistribution profile, evaluation of their bioaccumulative potential, assessment of biomolecular effects caused by these pollutants, and their aquatic half-life.…”

Exposure to Perfluoroalkyl Chemicals and Cardiovascular Disease: Experimental and Epidemiological Evidence

“…Since then, different PFAS, that are considered to accumulate in lower amounts and for shorter periods of time, have been introduced on the market and are currently in use. However, these new formulations are widely used without proper knowledge of their environmental disposition and potential toxicity (1,5,6).…”

Endocrine disruption by PFAS: A major concern associated with legacy and replacement substances

“…The broad category of PFAS substances comprises more than 4700 compounds, constituted by a hydrophobic carbon chain of variable length (ranging from C4-C17), wherein carbon-fluoride and carbon-hydrogen bonds alternate to form one or more perfluoroalkyl moieties (-CnF2n+1-) and a terminal group that confers hydrophilic properties (25). The functional groups, which are located in the terminal head region of the molecule, typically include sulfonates, sulfates, phosphates, carboxylates, amines, as well as alcohols or their combination, identifying subgroups of PFAS that can exist in a neutral, ionic or zwitterionic form, depending on the specific environmental conditions (26,27). As for the tail structure, the main carbon-fluoride chain can be linear or branched, with a partial or total degree of fluorination.…”