上饶市中心城区道路积尘和叶面尘重金属含量特征及健康风险评价

Heavy Metal Content and Health Risk Assessment of Road Dust and Foliar Dust in the City Center of Shangrao

采集了上饶市中心城区6大功能区中37个点位的道路积尘和叶面尘样品,对样品中重金属Cr、Cu、Ni、Pb和Zn含量进行了分析,并采用地累积指数法和美国环保署推荐的健康风险评价法进行了评价。结果表明:上饶市中心城区道路积尘中各重金属含量为Zn(282.8 mg/kg)>Cu(71.0 mg/kg)>Cr(64.7 mg/kg)>Pb(51.0 mg/kg)>Ni(23.0 mg/kg),叶面尘中各重金属的含量为Zn(427.8 mg/kg)>Cu(208.7 mg/kg)>Pb(121.1 mg/kg)>Cr(94.2 mg/kg)>Ni(30.8 mg/kg);叶面尘各重金属平均含量均高于道路积尘,其中Zn、Cu和Pb均显著高于江西省土壤背景值。商业区和经济开发区道路积尘中各重金属平均含量显著更高,文化教育区最低;而经济开发区和居住区叶面尘中重金属含量较高,公园绿地区和商业交通区较低。道路积尘中Zn、Cu和Pb主要来自工业污染源和交通排放尾气,叶面尘中Zn、Cu和Pb主要来源于工业污染源和生活污染源,Cr和Ni主要受到有色金属生产与深加工污染来源的影响。叶面尘重金属污染大于道路积尘,其中Cu、Zn和Pb的污染在轻度污染水平以上;道路积尘中的Zn和叶面尘中的Zn、Cu通过手-口摄入途径具有一定的非致癌风险;两种灰尘中的Cr、Ni均无致癌风险。

Road dust and foliar dust samples were collected from 37 sites in six functional districts in the city center of Shangrao.The contents of heavy metals,including Cr,Cu,Ni,Pb and Zn,in the dust samples were analyzed and evaluated via the ground accumulation index and the health risk assessment method recommended by U.S.Environmental Protection Agency.The results show that the contents of heavy metals in road dust in the city center of Shangrao were Zn(282.8 mg/kg)>Cu(71.0 mg/kg)>Cr(64.7 mg/kg)>Pb(51.0 mg/kg)>Ni(23.0 mg/kg).The contents of heavy metals in foliar dust were Zn(427.8 mg/kg)>Cu(208.7 mg/kg)>Pb(121.1 mg/kg)>Cr(94.2 mg/kg)>Ni(30.8 mg/kg).The average content of all heavy metals in foliar dust was higher than that in road dust,with Zn,Cu and Pb significantly higher than the soil background values in Jiangxi Province.The average contents of heavy metals in road dust were significantly higher in commercial and economic development districts,whereas the lowest average contents were found in cultural and educational districts.The contents of heavy metals in foliar dust in economic development and residential districts were higher than those in parks and green spaces as well as commercial traffic districts.Zn,Cu and Pb in road dust were originated predominately from industry and traffic emission.Zn,Cu and Pb in foliar dust were mainly derived from the industry and domestic pollution.Cr and Ni were mostly affected by non-ferrous metal production and deep processing.The heavy metal pollution in foliar dust was greater than that in road dust,with Cu,Zn and Pb above the light pollution level.Zn in road dust as well as Zn and Cu in foliar dust had certain non-carcinogenic risk through hand-oral ingestion.No carcinogenic risk for Cr and Ni was identified in both dusts.