A review of sources, multimedia distribution and health risks of novel fluorinated alternatives.

Per- and polyfluoroalkyl substances (PFASs) are a class of emerging persistent organic pollutants (POPs). They are widely used in industrial and consumer applications. Due to their persistence, bioaccumulation, long-distance migration and toxicity, it is important to find new compounds that can replace PFASs. The present review investigated the sources, fates and environmental effects of alternative PFAS compounds using surveys have been conducted over the past several years. Concentrations of PFAS alternatives in various environmental media, as well as human tissues, are summarized based on the available data. The results showed that hexafluoropropylene oxide dimer (HFPO-DA), hexafluoropropylene trimer acids (HFPO-TA), and 6:2 chlorinated polyfluorinated ether sulfonic acid (6:2 Cl-PFESA) have become the dominant global perfluorinated pollutants. Currently, there are a few toxicity assessments of these novel fluorinated alternatives, showing that they have systemic multiple organ toxicities. PFAS alternatives exhibited comparable or even more serious potential toxicity than legacy PFASs, indicating that these fluorinated alternatives are also harmful to the environment. Therefore, these alternatives require additional toxicological studies to confirm whether they can be used for a long time.