Title: Prenatal lead level and their association with neurodevelopment outcome in early infancy

Abstract

Background: In utero, exposure to toxic metal substances can cause severe neurodevelopmental deficits in the developing fetus and infants. Methods: We evaluated the association of umbilical cord blood lead concentration with early neurodevelopment performance (cognitive, language (receptive and expressive), motor (fine and gross), and social-emotion development). The Bayley Scale of Infants Developments-III (BSID-III) was used to perform neurodevelopment outcomes at an average age of 8 months. In this prospective study total of 167 mother-child pairs were enrolled from western Rajasthan, India. Cord blood lead concentration was measured in whole blood using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Multivariate regression was performed to understand the association of cord blood lead level with infant neurodevelopment outcome. Results: The obtained umbilical cord blood' lead concentration 5.0-10.5µg/dl was negatively associated with the sub-scale gross motor development score (β-coefficient with 95% CI; -0.29 (-5.0 – 0.11), p = 0.04). However, no associations were found with cognitive, language, gross motor, and social-emotional development scores. The umbilical cord blood lead concentration <5.0 µg/dl was also not associated with the BSID-III scores. Conclusion: The data suggest that umbilical cord blood lead concentration 0.5 to 10.5 µg/ dl has a negative association with early gross motor development during infancy.