PFAS Exposure and Human Health: From Ubiquity to Urgency

Pau-Chung ChenTaiwan Speaker PFAS Exposure and Human Health from Ubiquity to UrgencyPer- and polyfluoroalkyl substances (PFAS), often referred to as “forever chemicals,” are ubiquitous environmental contaminants widely used in industrial and consumer applications. Due to their extreme persistence, bioaccumulation potential, and endocrine-disrupting properties, PFAS have emerged as a major global public health concern. Our research team has conducted a comprehensive and systematic investigation into the human health effects of PFAS across the life course, integrating epidemiological analyses, biomonitoring, and biomarker-based approaches. Our findings demonstrate that PFAS exposure is associated with a broad spectrum of adverse health outcomes. In early life, prenatal and childhood exposure to PFAS has been linked to reduced fetal and childhood growth, disrupted thyroid function, delayed neurodevelopment, increased symptoms of attention deficit/hyperactivity disorder, elevated immunoglobulin E levels, impaired lung function development, and increased risks of childhood asthma. We have also identified associations with altered sex hormone profiles, including reduced testosterone and increased estradiol levels, as well as elevated uric acid concentrations. In adolescents and adults, our collaborative studies further indicate that PFAS exposure interferes with reproductive hormone regulation, accelerates subclinical atherosclerosis—as evidenced by increased carotid intima-media thickness—and elevates the risks of metabolic syndrome, diabetes, and premenopausal breast cancer. Collectively, these findings provide compelling evidence that PFAS exert multi-system effects spanning growth and development, neurobehavior, immune function, cardiometabolic health, and reproductive outcomes, thereby establishing a globally recognized body of evidence on PFAS-related health risks. Beyond scientific discovery, this lecture highlights how epidemiological evidence has informed policy action in Taiwan. In response to mounting health concerns, the use of PFOS was completely phased out beginning in 2017, followed by the progressive replacement of PFOA and related chemicals. PFHxS was subsequently designated as a toxic chemical substance and was effectively banned by the end of 2023, with limited exemptions for research and educational purposes. In 2024, the Executive Yuan approved the national Action Plan for the Management of Per- and Polyfluoroalkyl Substances, marking a critical step toward comprehensive PFAS governance. This lecture underscores the urgent need to translate scientific evidence into preventive action and demonstrates how sustained research can catalyze regulatory change. Addressing PFAS contamination will require coordinated efforts across science, industry, and policy to protect current and future generations from the long-term health consequences of these persistent chemicals.