Blood and Hair Mercury Levels in Neonates and Their Mothers in Zhoushan, China

Abstract

P-693 Abstract: Mercury (Hg), a heavy metal, is widespread and persistent in the environment. Exposure to hazardous Hg levels can cause permanent neurologic and kidney impairment. We investigated the status of Hg exposure of neonates and their mothers in Zhoushan, an island city in south China. Total Hg concentration was analyzed in maternal hair, umbilical core blood, and some fishes using Automatic Mercury Analyzer (Model DMA-80, Milestone Inc., Italy). Sociodemographic data, dietary habits during pregnancy, and other risk factors were also assessed. Between August and October 2004, 408 women who delivered their babies at the Third People Hospital in Dinghai region, Zhoushan City, took part in this study. 408 complete questionnaires, 405 maternal hair samples, and 406 cord samples were collected. Also 14 kinds of fishes, 5 pieces of each kind were bought at markets at Dinghai region Zhoushan city for Hg determination. The geometric mean total Hg concentration for cord blood and hair of mothers was 5.58 μg/L and 1246.56μg/kg, respectively. There was a strong correlation between maternal hair and cord blood Hg levels (r=0.82; p<0.01). The percentage of pregnant women with Hg levels exceeded the RfD (Reference Dose) was 69.9%. Frequency of fish consumption was associated with hair (r= 0.48; p<0.01) and cord blood (r= 0.54; p<0.01) Hg levels. Regression analysis showed that Hg levels in cord blood were significantly associated with maternal fish consumption, length of residency in Zhoushan city, and father's smoking behavior, while Hg levels in maternal hair were significantly associated with maternal fish consumption, and length of residency in Zhoushan city. The more fish consumed, the higher Hg levels in hair and blood cord (H=119.805, 94.384 respectively). Although Hg levels in neonates and pregnant women were generally below those considered hazardous, the long-term impact of exposure to Hg on childhood development needs to be investigated.