The Association of Prenatal Low-Level Mercury of Cord Blood and Maternal Body Mass Index in Shanghai

Abstraction Background: Perinatal mercury exposure is toxic to offspring’s central nervous system. Evidences suggested that blood mercury may be associated with obesity-related diseases in non-pregnant women. However, the relationship between maternal body mass (BMI) and cord blood mercury remains unclear. Methods: A longitudinal birth cohort study was conducted from 2012 to 2014 in Shanghai, southeast China. Maternal BMI before pregnancy and at delivery was extracted in 975 mothers. Total mercury in cord blood was examined by cold vapor atomic absorption spectrometry. Univarite and multiple linear regressions were used to estimate the relationship between Log mercury concentrations and maternal BMI with an adjustment for potential confounders. The threshold level analysis and two- piecewise linear model were performed to test the inflection point. Results: The geometrical means level of mercury in cord blood was 2.31 (0.18-13.24) µg/L. Of the 975 infants, only 31/975 (3.1%) had high blood Hg (= 5.8 µg/L)...