Common infections in children aged 6 months to 7 years after high prenatal exposure to perfluoroalkyl substances from contaminated drinking water in Ronneby, Sweden

Background: Perfluorinated alkyl substances (PFAS) are suggested to impair immune function in children. Previous studies investigating associations between prenatal PFAS exposure and common infections were performed in background-exposed populations whilst studies from high-exposed populations are lacking. Objectives: To investigate the association between prenatal PFAS exposure from contaminated drinking water and common infections in children aged 6 months to 7 years in Ronneby, Sweden. Methods: The cohort included 17,051 children, born 2003–2013, to mothers residing in Blekinge County at least one year within the five years before childbirth. Primary care diagnoses of infections in eyes, ears, respiratory- and urinary tract were retrieved from the Blekinge Healthcare Register. The residential history of the mothers served as a proxy for prenatal exposure; very high, high, intermediate, and background. We estimated hazard ratios (HR) by Cox proportional hazards regression with the Andersen and Gill extension for recurring events. Results: We observed an increased risk for ear infections (HR 1.28; 95% CI 1.03–1.58) in children with very high prenatal PFAS exposure, as well as suggestive but non-significant associations with eye- and urinary tract infections. Children with intermediate prenatal exposure had a reduced risk of eye infections (HR 0.86; 95% CI 0.77–0.95). No increased risk of respiratory tract infections was observed in any of the exposure categories. Discussion: This study was the first to investigate the association between high prenatal PFAS levels and common infections diagnosed in primary care, and it adds to a growing body of evidence of the potential immunotoxicity of early-life PFAS exposure.