Prenatal exposure to persistent organic pollutants and emotional and behavioral outcomes from early childhood to adolescence: Rhea Cohort Study in Crete, Greece

Abstract

Background: Persistent organic pollutants (POPs) are widespread, hazardous chemicals, but their impact on emotional and behavioral development is not well understood. This study aimed to investigate whether prenatal exposure to POPs influences internalizing, externalizing, and attention deficit hyperactivity disorder (ADHD) symptoms from early childhood to adolescence. Methods: We utilized longitudinally collected data from 467 mother-child pairs in the Rhea study. Concentrations of hexachlorobenzene, dichlorodiphenyldichloroethylene, and six polychlorinated biphenyl congeners (PCBs) were determined in maternal serum samples collected during early pregnancy. Mothers reported their children's internalizing, externalizing, and ADHD symptoms at ages 4 (Strengths and Difficulties Questionnaire, ADHD Test), 6, 11, and 15 years (Child Behavior Checklist, Conners' Parent Rating Scale). The associations between prenatal pollutant exposure and longitudinally studied outcomes were assessed using generalized estimating equation models. Results: In utero exposure to hexachlorobenzene and dichlorodiphenyldichloroethylene was not associated with emotional or behavioral outcomes. Prenatal exposure to PCBs was associated with decreased internalizing symptoms from childhood through adolescence and reduced ADHD symptoms at age 4 (adjusted β [95% confidence interval]: -0.17 [-0.29, -0.05], and -0.16 [-0.30, -0.02], per doubling of exposure, respectively). Sensitivity analyses confirmed these findings, though the association between PCB exposure and internalizing symptoms was not observed in women with sufficient gestational weight gain. Conclusions: Our findings suggest that prenatal POP exposure does not adversely affect emotional and behavioral development from preschool age through adolescence. Further research is warranted to elucidate the potential impact of gestational POP exposure on developmental trajectories.