摘要
根据北京城区大气环境质量监测点进行布点采集道路尘土样品。运用扫描电镜和X-射线能谱对样品表面进行了分析,道路尘土形态没有发现明显差异,C、O、Si 3种元素含量最高;道路尘土中8种重金属大小顺序为Mn>Zn>Cr>Cu>Pb>Ni>As>Cd,平均含量分别是545.05、104.28、92.67、47.18、41.49、20.79、14.10、0.31 mg/kg;北京城区道路尘土重金属主成分分析表明,Ni、Cd、Cr、Cu、Mn、Pb和Zn是受人为活动影响较为强烈的重金属,As目前受人为活动干扰较轻;地累积指数法(Igeo)评价表明Cr和Mn可能会对环境造成中度污染,Cu、Zn、As、Pb及Cd可能会对环境造成轻微污染,Ni基本不会对环境造成污染;潜在生态危害指数法(RI)评价表明Cd具有中等潜在生态风险,其余7种重金属潜在生态风险较低。
Samples of street dust were taken at the ambient air quality monitoring points assigned in Beijing City as a pollution investigation was carried out during January 2013. Then examination of the samples＇ surface by use of SEM and XRD showed that differences could hardly be detected in terms of dust morphology of those samples;and various elements were analyzed to determine the concentrations,which indicated concentrations of C,O and Si were higher. As to the concentrations of different heavy metal elements found in street dust,the rank in order was given as MnZnCrCuPbNiAs Cd,with the concentrations of 545.05,104.28,92.67,47.18,41.49,20.79,14.10 and 0.31 mg/kg respectively.Analysis of street dust＇s principal components suggested that Ni,Cd,Cr,Cu,Mn,Pb and Zn（As being an exception）were more likely affected by human activities. Method of index of geo-accumulation,Igeowas used for heavy-metal pollution evaluation,which showed that Cr and Mn may cause medium-level pollution,while Cu,Zn,As,Pb and Cd may do less,and Ni may not. Additionally,assessment by potential ecological risk index（RI）suggested that Cd may cause medium-level ecological risk,while RIs of seven others were low.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2014年第12期236-240,246,共6页
Environmental Science & Technology
基金
北京市教育委员会科技计划面上项目(KM201310011005)
关键词
重金属
污染
风险评价
道路尘土
北京
heavy metal
pollution
risk assessment
street dust
Beijing
