合肥市城区地表灰尘重金属分布特征及环境健康风险评价  

Distribution of Metals in Urban Dusts of Hefei and Health Risk Assessment

作　　者：李如忠[1] 周爱佳[1] 童芳[1] 吴亚东[1] 张萍[1] 喻佳[1] 

机构地区：[1]合肥工业大学资源与环境工程学院,合肥230009

出　　处：《环境科学》2011年第9期2661-2668,共8页Environmental Science

基　　金：安徽省科技攻关计划重点项目(07010302165);合肥工业大学大学生创新性实验计划项目(CXSY10130)

摘　　要：以安徽省合肥市城区为研究区域,采集居住区、商业区、工业区、文教区、交通区和公园绿地等6种功能用地共52个点位的地表灰尘,探析重金属Zn、Pb、Cu、Cd和Cr在不同功能区的分布特征,并以美国环保署(US EPA)推荐的健康风险评价模型,分别就儿童和成人2个群体在不同功能区、不同暴露途径下的重金属致癌和非致癌健康风险进行评估.结果表明,合肥市地表灰尘重金属污染相当严重,Cd、Zn平均值分别为安徽省土壤背景值的46和37倍,Cu和Pb为3～5倍,Cr为1.5倍.地表灰尘中Cr和Cd的致癌风险分别为3.22×10-7和2.26×10-9,低于US EPA推荐标准10-6;成人非致癌总风险为0.212,儿童则为1.259,超出了安全阈值1.0,表明合肥市地表灰尘已对儿童身体健康构成危害.经手-口直接摄取是健康风险的主要暴露途径.不同功能区非致癌总风险大小排序为:工业区>公园绿地>商业区>文教区>居住区>交通区,重金属非致癌风险大小排序为:Pb>Cr>Zn>Cd>Cu.This study focused on the characterization and the health risk assessment of heavy metals in the dust of Hefei City,China.Samples were collected from fifty two sampling points covering six land-use types.Most of the sites were impervious ground such as residential,commercial,industrial,educational and traffic areas,as well as public landscapes and city squares.Concentrations of Zn,Pb,Cu,Cd and Cr were measured to investigate their distribution and evaluate their risk to human health.The US EPA Health Risk Assessment Model was employed to evaluate the carcinogenic and non-carcinogenic risks of heavy metals to child and adult,respectively.The results showed that concentrations of Cd and Zn were 46 and 37 times higher than soil background values,respectively.The concentrations of Cu and Pb were 3-5 times,and Cr concentration was 1.5 times higher than the soil background values of Anhui Province.The carcinogenic risk indexes of Cr and Cd were 3.22×10-7 and 2.26×10-9,respectively,which were lower than the soil management standard of the US EPA,i.e.1.0×10-6.The total non-carcinogenic hazard index of the five metals for adults was only 0.212,but for children it reached to 1.259 and exceeded the safety threshold value（1.0）,suggesting that the adverse health impact on children exposure to metals in urban dusts were relatively serious in Hefei.The ingestion of dust particles was the major exposure pathway for health risk.The orders of non-carcinogenic hazard indexes of land-use types and heavy metals were industrial areapublic landscapes and city squarescommercial areaeducational arearesidential areatraffic area,and PbCrZnCdCu,respectively.

关 键 词：地表灰尘 重金属 暴露参数 暴露途径 健康风险评价 合肥市 

分 类 号：X502[环境科学与工程—环境工程] X503.1