Toxicity and Health Risks of PFAS

Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals that exhibit environmental persistence and are readily found in soil, water, and biological systems. These substances’ extensive application and reliability have resulted in global human exposure via contaminated food, drinking water, and consumer products. The toxicity of PFAS is complex, characterized by extended biological half-lives, bioaccumulation, and distribution across multiple organs, especially the liver, kidneys, and blood. The strong binding of these chemicals to proteins leads to disruptions in metabolic, hormonal, and immune pathways, thereby contributing to increasing health concerns. Exposure to PFAS is linked to various health risks, including immunotoxicity, developmental toxicity, hepatotoxicity, metabolic disorders, and an increased likelihood of specific cancers. Vulnerable groups, including children, pregnant women, and individuals with preexisting health conditions, exhibit increased susceptibility due to physiological and biochemical factors that affect the kinetics of PFAS. Various elements, including age, sex, species variations, comorbidities, and simultaneous exposure to other chemicals, can significantly influence the absorption, distribution, metabolism, and excretion (ADME) of PFAS, thereby affecting internal exposure and toxicological results. The ability of PFAS to traverse the placenta and accumulate in breast milk introduces further risks during essential developmental stages. Advanced physiologically based pharmacokinetic (PBPK) modeling is crucial for comprehending these dynamics across various life stages and exposure routes. Moreover, the existence of PFAS mixtures and their interaction with other contaminants adds a layer of complexity to toxicity assessments and public health responses. A comprehensive strategy is essential for addressing the long-lasting health consequences of PFAS and to inform effective regulatory and public health initiatives.