Associations of prenatal exposure to organophosphate pesticides with eczema and allergic rhinoconjunctivitis in 4-year-old children: The Japan Environment and Children's Study

This study aimed to evaluate the associations of prenatal exposure to organophosphate pesticides (OPP) with eczema and allergic rhinoconjunctivitis (AR) in 4-year-old Japanese children. The participants in this study were Sub-Cohorts of the Japan Environment and Children’s Study (JECS). The maternal urinary OPP metabolite concentrations of six dialkylphosphates (DAPs) were measured by lipid chromatography coupled with tandem mass spectrometry, corrected by specific gravity. Eczema and AR cases were defined according to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire for children at 4 years old. Multiple logistic regression analysis was used to examine the associations of DAPs with eczema and AR. Sub-group analyses were performed to explore the association between DAP metabolites and AR and eczema in children with elevated (≥170 IU/mL) and lower (