Early-life exposure to per- and polyfluoroalkyl substances and heavy metals and lower lung function in school-age...

Previous studies examining the associations of per- and polyfluoroalkyl substances (PFAS) and heavy metals (HMs) with lung function have yielded inconsistent findings. We investigated the associations of PFAS and HMs with lung function in a Korean birth cohort followed up to 10 years of age. Data from the Environment and Development of Children (EDC) cohort were used (n = 505). Serum PFAS and whole blood HM concentrations were measured at ages 2, 4, and 6 years. Lung function was assessed at ages 8 and 10 years. Linear mixed models were used to evaluate the associations of individual chemicals with repeated lung function measurements. Principal component analysis (PCA) within a doubly robust estimation framework was applied to examine the associations between chemical mixtures and lung function. In analyses for individual chemicals, several PFAS (e.g., perfluorooctanoic acid [PFOA] and linear perfluorooctane sulfonate [L-PFOS]) and HMs (e.g., mercury and cadmium), particularly those measured at age 2, were associated with lower lung function. In mixture analyses, higher age-2 PCA-derived exposure patterns characterized by PFAS-dominant components were associated with lower FEF_25-75 [β = 0.04, 95% confidence interval (CI): 0.01, 0.07], whereas higher age-2 HM-dominant components were associated with lower FEV₁/FVC (β = 1.33, 95% CI: 0.63, 2.03) at 8-10 years. These findings suggest that early-life exposure to PFAS- and HM-dominant mixtures, particularly around age 2 years, may adversely influence subsequent lung function. Our results highlight the importance of early-life prevention strategies to minimize exposure to these ubiquitous chemicals, particularly around 2 years of age.