UC San Diego

Background: Per- and polyfluoroalkyl substances (PFASs) and pesticides are ubiquitous environmental exposures associated with adverse health outcomes. Their impact on lung function in adolescents, particularly in combination, remains poorly understood.Methods: 381 adolescent participants from a prospective cohort study underwent measurements of serum PFAS (perfluorooctanoic acid [PFOA], perfluorooctanesulfonic acid [PFOS] and perfluorononanoic acid [PFNA]) and/or urinary pesticide levels in 2016. Pesticides selected for this analysis are widely used herbicides (Glyphosate, 2,4D) and fungicides (Ethylene thiourea). Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and forced expiratory flow (FEF25%-75%) were assessed in 175 participants in 2016 and 308 in 2022, with 102 overlapping both time points. We employed fixed-effects ordinary least squares regression to characterize the association between each PFAS or pesticide and each lung function measure and quantile g -computation to assess the association between lung function and the mixture of all PFASs/pesticides. Results: A one ng/mL increase in three PFASs was associated with a decrease in percent predicted FVC over the 6-year period (β[95% confidence interval]: PFOA (-11.33[-22.10,-0.59]) PFOS (-3.70[-7.00, -0.40]), and PFNA (-7.30 [-12.58, -2.01])). A one standard deviation increase in all PFASs and pesticides simultaneously was associated with an increase in percent predicted FEV1 (4.74[0.46, 9.02]). Conclusion: Our study provides evidence of an inverse relationship between PFAS exposure and FVC in adolescents, along with potential positive associations between PFAS and pesticide mixtures and FEV1. These results underscore the importance of continued research on the respiratory health effects of PFASs and pesticides.