Abstract:

     It is of great significancy to carrying out regional health risk assessment on heavy metals, which can further discuss healthy risk of heavy metals and serve for forecasting and early warning of regionally ecological geochemistry. Foreign risk assessment theory is applied to develop risk assessment on arsenic, cadmium, mercury and lead through investigating plant and atmosphere in Chengdu economic region. For noncarcinogenic risk, hazard index is calculated in the base of two exposure pathways including food intake and inhalation. And risk level resulting from cadmium inhalation is accounted for carcinogenic risk. It is indicated that cadmium and lead have upper ecological risk in Chengdu economic region, and hazard index of cadmium is the highest. According to total risk, risk difference between areas is obvious and the upper risk exists in Deyang and Chengdu districts. Comparing different exposure routes’ contributing proportion to total risk, proportion of grain is the highest, which holds 71.19% of total risk, other are potato, vegetable, bean and inhalation by decreasing sequence respectively. For carcinogenic risk, investigated region, where average value of carcinogenic risk is 7.6×10^-6, locates acceptable risk level on the whole, and high risk areas mostly locate west of Deyang and suburb of Leshan city, in which atmosphere environmental problem should be taken more attention.

Key words: heavy metals, risk assessment, risk, hazard index, Chengdu economic region