德阳镉污染农田区生态安全性及居民健康风险评价

Ecological Security and Residents Health Risk Assessment on Polluted Farmland by Cadmium in Deyang Region

对四川德阳地区土壤镉等重金属污染区大米、小麦安全性进行了评价，并建立了水稻籽实镉含量与根系土镉、有机质含量、pH值的回归方程，据此预测德阳地区水稻镉超标面积。根据当地居民主食（大米、小麦）镉等重金属元素的摄入量，对镉污染区人体健康风险进行了评价。研究表明，德阳地区大米、小麦重金属污染均以镉为主。预测水稻镉超标面积达1547．95km2，占研究区面积的73．47％。人发镉等重金属元素存在明显异常。人发镉含量高值区与土壤镉异常和居民主食镉摄入量高值区分布有一致性。什邡市、绵竹市、安县、旌阳区、广汉市居民主食（大米、小麦）镉摄人量均超标2～10倍。重金属污染造成人体健康风险最高的是绵竹、什邡地区，其次是旌阳区。

The security of rice and wheat is assessed in cadmium pollution area in Deyang region of Sichuan Province, and regression equation about Cd content in rice seed, Cd content in root soil, organic matter and pH is established, by which the area of Cd over standard rice in Deyang region is forecasted in this study. Also hu- man health risk assessment on Cd pollution area is carried out according to heavy metal elements such as Cd in- take of local residents＇ staple food. This study indicates that Cd is the main heavy metal pollution element of rice and wheat in Deyang region, and the paddy area over standard of Cd is predicted about 1,547.95 square kilometers, which accounts for 73.47% of investigated region＇s area. Obvious Cd abnormity is found in human hair, in which the area of high Cd content is consistent to the distribution of soil abnormity and high content of residents＇ staple food intake. It shows that Cd intakes in Shifang City, Mianzhu City, An County, Jingyang District and Guanghan City exceed the standard by 2 - 10 times, and Mianzhu City and Shifang City have the most human health risk from heavy metal pollution, secondly Jingyang District.