Total and methyl mercury levels in human scalp hairs of typical populations in China by NAA, GC(EC), and other techniques.

The contents of total and methyl mercury in scalp hair samples of 1179 fishermen living in a typical Hg-polluted region in northeast China and 27 lying-in women and their newborns in Beijing have been determined by INAA, GC(EC), and other techniques. Only 18 of all fishermen had Hg contents above 5 micrograms/g, which indicates that the Hg pollution there has been substantially alleviated. The longitudinal Hg patterns of the lying-in women showed a gradually lowering tendency during pregnant period. Further, the Hg contents of the newborn babies generally were above or close to those of their mothers, confirming the mechanism that the methyl Hg, an organic species of Hg with high toxicity, is readily able to penetrate the placental barrier and to accumulate in the fetus. Thus, the mercury poison has occurred at the early stage of pregnancy.