Endocrine-Disrupting Chemicals in School Indoor Air and Childhood Health: Baseline evidence for climate-resilient and health-protective school environments

Introduction. Endocrine-disrupting chemicals (EDCs) in school indoor air may affect children's respiratory and skin health. Schools are key indoor environments shaped by climate adaptation, where persistent pollutants such as PFAS and BFRs are present, potentially impacting children's health through multiple exposure pathways. Materials and methods. This study assessed children's exposure to endocrine-disrupting chemicals in 20 public primary schools in Porto, Portugal, involving children aged 5-11 years. Methods included systematic reviews and meta-analyses of EDCs, PFAS, and childhood respiratory/skin outcomes, environmental monitoring with 28-day passive air sampling in 80 classrooms across 20 schools, and statistical analyses using meta-analysis, multivariable and multilevel regression to evaluate exposure-outcome associations. Results. Systematic evidence included 61 EDC studies and 28 PFAS studies with 64,851 participants. Childhood health determinants showed multiple individual, familial, and environmental factors influencing respiratory and skin outcomes. Environmental monitoring detected total BFRs ranging from 28.12 to 154.54 pg/m³ and 64 PFAS targeted in 8 schools, with 66.5% indoor PFAA precursors. Associations were found between BFRs and asthma/wheezing, and PFAS with wheezing and eczema. Replacement BFRs predominated, but legacy BFRs remained detectable. Conclusion. School indoor air may contribute to children's exposure to legacy and emerging PFAS and BFR. Observed associations highlight the interplay among chemical exposures, early-life factors, and indoor environments, supporting continued monitoring, climate-resilient and health-protective school environments, and longitudinal research to clarify potential health effects. Key messages. School indoor air contains endocrine-disrupting chemicals including PFAS and BFRs that may affect children's respiratory and skin health. Associations were observed between exposure to BFRs and PFAS and increased risks of asthma, wheezing, and eczema in children. Findings support the need for climate-resilient and health-protective school environments and ongoing monitoring of chemical exposures.