桂西北稻田重金属污染及健康风险评价  

Heavy Metal Pollution and Health Risk Assessment of Paddy Soil in Northwestern Guangxi

作　　者：郑富海[1] 黎宁 张卫[1] 陆覃昱[1] 陈仕淼 顾明华[1] 何冰[1] 

机构地区：[1]广西大学农学院/"农业环境与农产品质量安全"广西高校重点实验室,广西南宁530004 [2]广西壮族自治区环境监测中心站/"土壤环境污染与生态修复"广西人才小高地,广西南宁530028

出　　处：《西南农业学报》2017年第8期1886-1893,共8页Southwest China Journal of Agricultural Sciences

基　　金：广西农业厅专项项目(稻米Cd含量预测模型的建立及广西水稻产地Cd污染评估);广西科学研究与技术开发计划项目(桂科合14125008-2-30)

摘　　要：【目的】了解广西西北稻田土壤重金属污染情况及稻米的健康风险,为重金属污染治理提供理论依据。【方法】采集该区域98个稻田点位的土壤及稻米,分别测定Cu、Pb、Cd、Cr、Zn和As等6种重金属的含量。采用单因子指数法、内梅罗指数法和潜在生态危害指数法对稻田土壤的污染状况进行评价,以《土壤环境质量标准》(GB15618-1995)中Ⅱ级标准作为参考值,采用高危商(HQ)和高危指数(HI)法对稻米健康风险评价。【结果】稻田土壤Cu、Pb、Cd、Cr、Zn和As的平均含量分别为18.21、64.97、0.98、45.55、147.88和11.62 mg·kg^(-1),各元素含量的变异系数均较大。土壤的内梅罗指数为1.416,表明土壤受到轻度污染,主要污染元素为Cd,其次为Zn,极少部分区域存在Pb和As污染。根据潜在生态危害指数(RI),土壤总体处于轻微生态危害程度,其中Cd对RI的贡献率最大,其次为As。稻米Cu、Pb、Cd、Cr、Zn和As的平均含量分别为5.6400、0.3668、0.1625、0.3879、26.7800和0.2974 mg·kg^(-1)。根据高危指数(HI)法,稻米可能存在健康风险,其中As对HI的贡献率最大。【结论】供试水稻土重金属污染属于轻度污染水平和轻微生态危害程度,主要污染物为Cd、Zn;稻米中的主要污染元素为Pb和Cd,但可能引起稻米健康风险的重金属元素为As。[ Objective ] The study aims to provide a theoretical basis for the heavy metal pollution control, the heavy metal pollution of paddy soil and its health risk in Northwestern Guangxi had been evaluated. [ Method]98 soil and rice samples were collected front paddy fields in Northwestern Guangxi, and each contents of Cu, Pb, Cd, Cr, Zn and As were determined respectively, to evaluate the pollution and health risk of heavy metal. The soil environmental quality was evaluated by the single factor pollution index method, the Nemerow index method and potential ecological hazard index method, as well as using the grade lI in Environmental quality standard for soils （ GB15618-1995 ） as a reference value. The health risk of the grain to residents was evaluated by the high risk quotient （HQ） method and High risk index （HI） method. [ Result]The average contents of Cu, Pb, Cd, Cr, Zn and As of soil were 18.21, 64.97, 0. 98, 45.55, 147.88 and 11.62 mg · kg ^- 1, respectively. There were large variations of heavy metal contents in 98 soil samples. The Nemerow index of research area was I. 416, which reached to the grade II standard of soil environmental quality assessment classification, meant the soil were lightly polluted by heavy metals. According to the single factor pollution index, the main pollution element in research area was Cd, followed by Zn, and there were Pb and As pollution in very few research areas. According to the potential ecological risk index （RI） , the soil in the study area was in a slight degree of ecological harm, and the contribution rate of Cd to RI was the largest, followed by As. The average contents of Cu, Pb, Cd, Cr, Zn and As in rice were 5. 6400, 0. 3668, 0. 1625, 0. 3879, 26. 7800 and 0. 2974 mg · kg^-1, respectively. According to the high-risk index （HI） , there might be a health risks in rice grains collected in research area. Among the 6 heavy metals, As made the highest contribution to HI. [ Conclusion] The heavy-metal pollution of research area was at the slight poll

关 键 词：稻田 重金属污染 生态评价 健康风险 桂西北地区 

分 类 号：S511[农业科学—作物学]