Emerging Environmental Obesogens: Current Knowledge on Per- and Polyfluoroalkyl Substances, Micro-Nano Plastics, and Tire Additives

The growing prevalence of obesity worldwide has been attributed not only to behavioral and genetic factors but also to chronic exposure to environmental chemicals known as obesogens. This review synthesizes current evidence on three underexamined classes of emerging environmental obesogens: per- and polyfluoroalkyl substances (PFAS), micro- and nano-plastics (MNPs), and tire-derived organic pollutants (TDOPs), with particular focus on their metabolic impacts and potential synergistic effects. These contaminants are widely detected in drinking water, food products and food-contact materials, and epidemiological evidence increasingly links them to dysregulation of lipid metabolism, impairment of glucose homeostasis, and obesity-related outcomes. These contaminants may disproportionately affect marginalized communities due to synergistic toxicity, systemic exposure disparities, and greater economic vulnerabilities. The review discusses shared exposure pathways, plausible molecular mechanisms, and heightened human vulnerability. Critical knowledge gaps are identified, including limited data on emerging PFAS, nanoplastics and their additives, chronic co-exposures, and analytical challenges in tracking human exposure. By integrating evidence across these contaminant classes, the review highlights the need for coordinated research efforts to better characterize the cumulative obesogenic burden of emerging environmental pollutants.