Prenatal Exposure To Organochlorine Pesticides And Neuropsychological Development In Preschool Children

Abstract

Background. Animal studies indicate that some organochlorine pesticides (OCPs), such as 4,4´-dichlorodiphenyldichloroethylene (4,4´-DDE), hexachlorobenzene (HCB) and beta-hexachlorocyclohexane (b-HCH) may be developmental neurotoxicants. However, findings across human studies are inconsistent. This study aimed to investigate the possible effects of prenatal exposure to OCPs on the neuropsychological development of preschoolers from a Spanish birth cohort. Methods. In a Spanish multi-center study, cognitive and motor abilities of children (N=1,726; mean age=4.8 years) were assessed by means of the Spanish version of the McCarthy Scales of Children's Abilities (MSCA). Global intellectual function was evaluated with the general cognitive index (GCI), which combines three out of the five domains of the MSCA (verbal, perceptual-performance, and quantitative). In addition, psychomotor development was assessed using the motor subscale of the MSCA. 4,4´-DDE, HCB, and b-HCH were measured in maternal serum at 12 weeks of pregnancy. Multivariate linear regression models were performed controlling for several potential confounding factors (including parental social class and education, diet, child age, psychologist, and maternal IQ). Differences by sex were investigated, including the interaction of this variable with the contaminants in the main analysis. Results. Median (P25-P75) concentrations of HCB, 4,4´-DDE, and b-HCH in maternal serum were 0.31 (0.17-0.52), 0.86 (0.51-1.57) and 0.14 (0.07-0.24) ng/mL, respectively. In general, negative associations were found between OCP concentrations and MSCA subscales, but none was statistically significant. Finally, interaction with sex was not significant in any case. Conclusions. No statistically significant associations between OCPs and child neuropsychological development were found in preschool children from a Spanish birth cohort.