Epidemiological investigation on mercury contamination in gold mining and its effect on health

摘要

In this paper, it is reported the environmental contamination of mercury in gold mining in China and the effect of mercury exposure on health. The results showed that Hg concentration of air in the Hg|use workshop, the mining area and the population’s living area were 0.058 mg/m 3, 0.047 mg/m 3 and 0.043 mg/m 3, respectively. Hg content of air in the suburbs 5 km from the mining area was 0.007 mg/m 3. The difference in Hg concentration of air was statistically significant ( p 0.05). All of the values determined above were excessed the Chinese national standards. Hg concentration of snowfall and soil in the mining area were 0.058 mg/L and 2.78 μg/g. Both of them differed from those of the living area ( p< 0.01 and p <0.05). Hg content of the waste water was up to the national emission standards. Hg contents of wild plants differed inside as compared to outside the mining area ( p <0.05). But Hg content of plants of the two places was both in the range of the background. The results that Hg levels accumulated in the bodies showed that Hg concentration of hair, blood and urine of the workers of the Hg|exposed group (group I, GI) were all higher than those of the non|Hg|exposed group (group II, GII). Hg in hair and urine was statistically significant ( p<0.001 and p<0.005) between the two groups. Hg content of hair of twenty|five percent of workers in GI was higher than 4 ppm, and a small number of workers in this group was higher than 10 ppm. The Hg content of urine of eighty percent of workers in GI was higher than that of the Chinese normal human’s standard. Some slight but typical clinical symptoms, of Hg poisoning were found in some worker’s by clinical examination. It proved that the environment of the gold mining area was polluted by Hg vapor in varying degrees. The population was suffering from mild degree of Hg poisoning. It pointed to the fact that protecting the ecosystem and human’s health against Hg pollution should be paid great attention in this gold mining area.