Effect of in Utero Exposure to Manganese on the Neurodevelopment of the Infant

Abstract

O-29C7-3 Background/Aims: Manganese (Mn) is an essential trace element and common component of food, water and air. Prenatal Mn exposure during gestation may affect fetal and infantile neurodevelopment. However, reports on in utero Mn exposure and infant's neurodevelopment are rare. This study was conducted to establish a possible relationship between prenatal exposure to Mn and mental/psychomotor development of infant at 6 months of age. Methods: We analyzed data from a birth cohort, Mothers and Children's Environmental Health (MOCEH). Study population included 259 pregnant women and infant (at 6 months of age) pairs, excluding infants <37 weeks of gestation. We assessed mental and psychomotor development in infancy using the Mental/Psychomotor Development Index (MDI/PDI) of Korean version of Bayley Scales of Infant Development II (BSID-II). The relationship between prenatal Mn exposure and MDI/PDI scores was evaluated with linear regression and ANOVA. Blood Mn was measured at third trimester of pregnancy. Results: An adverse effect of prenatal Mn exposure on MDI scores at 6 months of age was not significant. PDI scores were significantly related to the prenatal maternal blood Mn level. A nonlinear relationship was associated between prenatal manganese levels and PDI scores after adjustment for potential confounders: gestational age, infant's gender, birth order, maternal body mass index, maternal age, maternal education, breastfeeding, exposure to environmental tobacco smoke during pregnancy, and presence of atopic dermatitis after birth. Conclusion: The results of study show that prenatal manganese levels impairs psychomotor development in infancy. While no cut off point is established to define Mn poisoning, it is suggested that blood Mn level of ≥30μg/L may be associated with an adverse neurobehavioral function in infants.