【摘要】 2015年7月3—17日,采集天津3条典型道路路边道路交通环境中不同粒径段的PM_2.5样品,分析其中的12种金属元素,并开展健康风险评价。结果表明:（1）3种典型道路上PM_2.5均超过《环境空气质量标准》（GB 3095—2012）中二级日均限值（75μg/m³）。主干道、次干道、快速路上PM_2.5中金属元素累计质量浓度分别为0.68、0.74、0.67μg/m3。（2）多数金属元素的粒径分布存在明显差异。Zn和Cu为轮胎和刹车片磨损标志物,峰值在较大粒径颗粒物上。Sb通常作为添加剂以Sb2S3的形式加入到刹车片中,峰值出现在>0.2～1.0μm粒径段。（3）Cr、Co、Ni、Cu、Zn、As、Cd、Sn、Sb和Pb的富集因子>10,受到人为源的作用。对于儿童和成人群体,全部道路路边环境的非致癌风险危险指数均大于1,具有非致癌风险。PM_2.5中Cr、Co、Ni、As、Cd的致癌风险基本上均超过美国环境保护署推荐的可接受风险阈值（10-6）,具有明显的致癌效应。更多还原

【Abstract】 PM_2.5 of different particle size segments were collected from three different grade roads from July 3 to July 17 in 2015 in Tianjin and 12 kinds of metal elements were analyzed.The health risks of heavy metal elements in PM_2.5 were studied.The results showed that:（1）PM_2.5 on the three typical roads exceeded the secondary average daily limit level（75μg/m3）of "Environmental air quality standard"（GB 3095-2012）.The cumulative mass concentrations of metal elements in PM_2.5 on the major road,secondary road and expressway were 0.68,0.74,0.67μg/m3,respectively.（2）There were significant differences in the particle size distribution of most metal elements.Zn and Cu were markers of tire and brake pad wear,particulately with peaks on larger particle size particles.Sb was usually added as an additive to the brake pads in the form of Sb2 S3,with peaks appearing in the particle size range of>0.2-1.0μm.（3）The enrichment factor ratio of Cr,Co,Ni,Cu,Zn,As,Cd,Sn,Sb and Pb were greater than 10,which were highly enriched by the roadside and related to anthropogenic sources.The non-carcinogenic risk index of all roadside environments was greater than 1 indicating that there was non-carcinogenic risk of manganese exposure in children and adults.The carcinogenic risk of Cr,Co,Ni,As and Cd generally exceeded the acceptable risk threshold（10-6）recommended by the US Environmental Protection Agency,and there was a significant carcinogenic effect.更多还原