Assessment of Environmental and Health Risks of Cd in a Soil-Rice System in Zhejiang, China.

In the paddy field in Wenling Valley, Zhejiang Province, 95 soil samples and 95 rice samples were collected to study Cadmium (Cd) contamination of the soil and rice. Meanwhile, both environmental and health risk of Cd were evaluated in this study. Based on the background value of soils in Zhejiang as critical value, 94.79% soil was polluted by the heavy metal Cd, and 27.08% soil was polluted by Cd based on Chinese national environmental second grade standard value. For the Cd in rice, 9.78% rice was polluted based on the threshold of Chinese food hygienic standard. Muti-factor regression analysis results showed that rice Cd concentrations had high correlations with soil clay, soil Fe₂O₃, and soil Cd concentrations. Spatial distribution patterns  of soil and rice Cd were delineated using geostatistics and GIS. Health risk evaluation model was employed in this study to analyze the soil heavy metal risk to local people. Children were more easily affected by soil heavy metals,for that hazard indexes for children were 3 times of adult health£®