Environment-wide association study of five per- and polyfluoroalkyl substance (PFASs) exposure pathways in Korean adolescents from the Korean National Environmental Health Survey (2018-2020).

Per- and polyfluoroalkyl substances (PFASs) are widely used in consumer products and are easily encountered in daily life. PFASs that accumulate in the human body can negatively affect adolescent health. This study aimed to identify key exposure pathways that influence serum PFAS levels in Korean adolescents, using data from the Korean National Environmental Health Survey (2018-2020) cycle 4. By employing an environment-wide association study, we assessed residential, lifestyle, and dietary factors associated with serum PFAS levels. Serum levels of five PFAS compounds-perfluorooctanoic acid, perfluorooctane sulfonate, perfluorohexane sulfonate, perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA)-were measured in 825 adolescents. Multivariable linear regressions were performed to explore the association between serum PFAS levels and 102 potential exposure-pathway variables. The Benjamini-Hochberg procedure was then applied to calculate false discovery rate-adjusted p-values, with values < 0.01 considered statistically significant. For internal validation, least absolute shrinkage and selection operator regression was conducted 3000 times. We found that frequent fish consumption (>once a week) was strongly associated with increased serum levels of PFNA and PFDA. Frequent consumption of shellfish (>once a month), crustaceans (>once a week), and vegetables (≥once a day) was associated with increased serum levels of PFDA. Living near roads with self-reported high traffic volume was linked to higher PFDA concentrations. Further research is necessary to assess additional exposure pathways and to develop effective strategies to minimize PFAS exposure during adolescence.