摘要
以典型有色金属矿山城市铜陵市为对象,从工业用地、居住用地、商贸用地、文教用地、交通用地和城市广场等6种主要用地类型中,选择64个采样点位,采集表土和不透水地面灰尘样.在对Pb、Cu、Cr、Zn、Ni、As和Cd含量分析测试的基础上,利用美国国家环保局（US EPA）推荐的健康风险评价模型,就儿童和成人群体在不同功能用地、不同暴露途径下的重金属致癌和非致癌风险进行分析和评估,并对表土与灰尘的健康风险效应进行比较.结果表明：铜陵市表土与灰尘重金属含量显著高于该市土壤背景值,意味着铜陵城区土壤和地表灰尘已遭受较为严重的重金属污染;重金属Cr、Ni、As和Cd的致癌风险均值分别为4.30 ×10^-7、7.18 ×10^-9、4.26 ×10^-4和7.58 ×10^-8,不同功能用地的致癌风险均显著超过US EPA推荐的可接受风险阈值范围10^-6--10^-4和国际辐射防护委员会（ICRP）推荐的最大可接受风险值5.0× 10^-5;表土与灰尘的儿童非致癌风险分别高达5.20和16.58,灰尘对成人的非致癌风险达2.80,都远高于安全阈值1.0,表明铜陵市表土与地表灰尘已对公众身体健康构成危害;主导致癌与非致癌风险效应的主要污染因子是As,主要暴露途径是手-口摄入途径.
This research focused on the potential health risk assessment of heavy metals（including As） pollution in urban topsoil and dust from Tongling,a typical nonferrous metal mining city,China.Samples were collected from sixty four sampling sites covering six land-use types,that is,industrial,residential,commercial,educational and traffic areas,as well as city squares.The heavy metal（Pb,Cu,Cr,Zn,Ni,As and Cd） contents of all samples were analyzed and health risk assessment were conducted for children and adult respectively,using the risk models recommended by the United States Environmental Protection Agency（US EPA）.The levels of heavy metal elements in the urban topsoil and dust of Tongling are much higher than the natural soil background level in the regions,suggesting that the urban topsoil and dust have been heavily polluted by those metals.The exposure to Cr,Ni,As and Cd results in a cancer risk value of 4.30 ×10^-7,7.18 ×10^-9,4.26 ×10^-4 and 7.58 ×10^-8,respectively,and the mean cancer risk for such six land-use types vary in the range of 1.55 ×10^-4-9.14× 10^-4,significantly higher than the acceptable or tolerable range of threshold values 10-6-10^-4 recommended by USEPA,and the 5.0 10-5 probability level deemed unacceptable by the International Commission on Radiation Protection（ICRP）.The exposure to topsoil and dust yields an aggregate Hazard Index of 5.20 and 16.58 for children,respectively,while the exposure to dust results in an aggregate Hazard Index of 2.80 for adult,far exceeding the threshold value of 1.0.As a predominant single contributor both to carcinogenic and non-carcinogenic risks,arsenic is the trace element of most concern.In addition,the highest risk is associated with ingestion of soil particles.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2012年第12期2261-2270,共10页
China Environmental Science
基金
安徽省环保厅环保公益项目(2011-010)
关键词
有色金属矿山
重金属
表土
灰尘
健康风险评估
铜陵市
nonferrous metal mine
heavy metal
topsoil
urban dust
health risk assessment
Tongling City
