Prenatal Exposure To Mercury And Neuropsychological Development In Preschoolers Children

Abstract

Introduction The purpose of this study is to evaluate the association between prenatal exposure to mercury (Hg) and children´s neurodevelopment. Methods Study subjects were children participating in a Spanish birth cohort study (n=1362, 2003-2012). Cord blood total Hg was measured by atomic absorption spectrometry. Information on covariates and confounders was obtained through questionnaires. Neuropsychological development was assessed at age 4-6 years by using the McCarthy Scales of Children's Abilities (MSCA). The MSCA includes six scales (verbal, perceptive performance, numeric, memory, motor) and a general cognitive index. Multivariate linear regression models were conducted to evaluate the association between Hg exposure and neurodevelopment test scores in all children and stratifying the study population by quartiles of maternal fish consumption. The interaction p-values between Hg and maternal fish consumption were obtained. Results Hg concentrations were relatively elevated (GM: 8.8µg/dL). A doubling in Hg levels was positively and significantly associated with all the test domains, even after maternal fish consumption adjustment. When the study population was stratified by quartiles of maternal fish intake the association between Hg and neurodevelopment test scores was inverse among women in the first quartile but not significant. This association became positive and stronger with increasing fish consumption. The interaction p-value was significant (p