Abstract:
In the paper, researches have been conducted on the 45 stations that monitor the heavy metals including cadmium, chromium, arsenic, NH
3-, mercury, copper and lead in the water of Liao River estuary by means of sampling, processing and data analysis. The Health Risk Assessment Model recommended by the US Protection Agency has been employed to conduct an initial health risk assessment on the water environment of Liao River Estuary. The result shows that the concentration ranges of the heavy metals are as followings:the range of cadmium is 0.23~0.93μg/L; chromium 0.8~8.3μg/L; arsenic 0.29~0.51μg/L; NH
3-:7.59~322μg/L; mercury 0.007~0.135μg/L; copper 2.4~6.2μg/L; lead 0.11~0.69μg/L. The result has shown that the annual risk per capita that the gene toxic substances ( cadmium/ chromium and arsenic) have posed to human health is far greater than that of non-gene toxic substances(NH
3-, mercury, copper and lead). Among the heavy metals, chromium tops the list in terms of the annual risk per capita for human health. In addition, this paper has divided the general influencing factor of the surface water environment into five grades, among which the northwest of the researched region ranks in the highest grade for this region belongs to Daling estuary.