Environment/Climate Change
Prenatal Exposure to Mixtures of Non-persistent Chemicals and Childhood Obesity through Preadolescence: A Meta-analysis across 8 European Birth Cohorts Nuria Güil-Oumrait* Nuria Güil-Oumrait Martine Vrijheid Vincent Jaddoe Charline Warembourg Barbara Heude Sabrina Llop Loreto Santa-Marina
Background: Experimental studies have shown potential obesogenic effects resulting from early-life exposure to non-persistent chemicals commonly found in plastics and personal care products. However, epidemiological studies examining this association have been inconsistent, often limited by sample size or lacking a longitudinal approach. This study aimed to evaluate the associations between exposure to phenols and phthalate metabolites during pregnancy and offspring obesity outcomes in 8 birth cohorts spanning from north to south Europe.
Methods: We used harmonized data from over 5000 mother-child pairs with maternal urinary concentrations of 3 bisphenols, 4 parabens, benzophenone-3, triclosan, and 10 phthalate metabolites. Body Mass Index (BMI) z-scores were derived for three key developmental periods (early childhood: 2-5 y, adiposity rebound: 5-9 y, and preadolescence: 9-13 y). Adjusted associations were examined using DataSHIELD, employing linear mixed-effects models fitted separately for each cohort and combined through random effects meta-analysis. Interactions by age were tested, and linear fixed effects models assessed associations at each outcome time-point.
Results and conclusions: Preliminary findings, based on 3045 mother-child pairs from 4 cohorts, reveal an association between prenatal exposure to mono-ethyl phthalate (MEP) and an increase in childhood BMI z-score (β = 0.08, 95%CI: 0.00, 0.18). Fixed effects models indicate more pronounced associations between phthalate metabolites and BMI at older stages, specifically during preadolescence. These results suggest that prenatal exposure to MEP, a metabolite of diethyl phthalate widely used in fragranced cosmetics, is associated with increased BMI in childhood. Over the next 2 months, we anticipate definitive results, including the remaining 4 cohorts and an assessment of sex interactions.