湖南市场和污染区稻米中As、Pb、Cd污染及其健康风险评价

为了更好地了解和评价湖南大米中As、Pb和Cd含量及其对人体的健康影响,在对湖南矿区和冶炼区水稻土壤重金属污染调查的基础上,分别以湖南各地市场大米和污染区当地生产的稻谷样品为例,对其进行重金属含量分析及对人体的健康风险评价.结果表明,湖南各地市场大米样品中As、Pb和Cd的平均含量分别是0.20、0.20和0.28mg·kg-1,其中,衡阳市场大米中的As、Pb和Cd含量最高,其次是株洲和湘潭市场的大米.污染区稻谷中As、Pb和Cd含量分布均为:谷壳糙米精米,污染区精米中As、Pb和Cd的含量分别是0.24、0.21和0.65mg·kg-1,其中,来自衡阳常宁市水口山铅/锌矿区的稻谷样品中的As、Pb和Cd含量最高,其次是株洲清水塘冶炼区和湘潭锰矿区的稻谷.与市场大米样品相比,污染区精米中As、Pb和Cd的平均含量比市场大米样品高.无论是市场大米样品,还是从污染区稻田采集的稻米,均以衡阳地区稻米中的As、Pb和Cd污染最为严重,其次为株洲和湘潭地区.在As、Pb和Cd的健康风险评价中,Cd是湖南各地稻米中影响人体健康的主要因子,株洲和湘潭的Cd污染区达到90%以上,其次是As和Pb.

Arsenic,lead, and cadmium pollution in rice from Hunan markets and contaminated areas and their health risk assessment

Among all rice producing areas in China,Hunan Province (south central China) is the greatest grain production province.Based on our previous study of soil contamination,the concentrations of As,Pb,Cd in rice from Hunan markets and contaminated areas,and the human health risk assessment of As,Pb,Cd to an adult through the rice consumption pathway around those areas were investigated.The results showed that the mean concentrations of As,Pb,and Cd in market rice were 0.20,0.20,and 0.28 mg·kg^-1,respectively.In particular,the highest concentrations of As, Pb,and Cd were found in Hengyang's market rice samples,followed by Zhuzhou's and Xiangtan's market rice samples.In the contaminated rice,the average contents of As,Pb,and Cd were 0.24,0.21 and 0.65 mg·kg^-1 respectively,higher than those in market rice.Among the contaminated rice samples,the highest concentrations of As,Pb,and Cd were found in rice from the Hengyang Shuikou - shan Pb/Zn mine area,followed by the zhuzhou Qingshui-tang smelting and Xiangtan manganese mine areas.All results from market and field rice indicated that Hengyang was the area most contaminated by As,Pb,and Cd,followed by Zhuzhou and Xiangtan.Among the studied heavy metals,cadmium is the predominant risk factor for an adult exposed through rice consumption,amounting to over 90% of the hazard index values in contaminated soils from the Zhuzhou and Xiangtan impacted areas.