北京市不同年龄人群PM2.5载带重金属的健康风险

在北京中心城区（北2~3环路）利用大流量颗粒物采样器连续采集了2016年全年共218个PM_2.5样品，通过电感耦合等离子体原子发射光谱法（ICP-AES）测定了其中9种重金属元素，即As、Cd、Co、Cr、Cu、Ni、Pb、V、Zn.结合我国人群暴露参数，利用美国环保署推荐的健康风险评价模型，对北京市1~80岁不同年龄人群致癌非致癌健康风险进行了评价.结果显示：2016年北京市PM_2.5重金属中Zn、Pb、Cu质量浓度最大，依次为（291±553）ng/m³、（53.6±73.5）ng/m³、（25.0±59.7）ng/m³，其次为As、Ni；所有重金属中，As具有最大致癌风险贡献（62.5%），Co具有最大非致癌风险贡献（29.0%）.不同年龄、性别人群的重金属危害指数（HI）均小于1，显示无非致癌健康风险，另外，儿童期HI值大于成人期.不同年龄、性别人群的重金属总致癌风险（CR）均位于10^-6与10^-4范围（即每1万~100万的人群数量中增加1个癌症患者），显示无显著致癌风险，另外，随着年龄的增长致癌风险增加.此外，同一年龄人群中，女性致癌及非致癌风险均稍低于男性.

Health risk of PM2.5-bound heavy metals for different age population in Beijing,China

A total of 216 daily PM_2.5 samples were collected in 2016 by a high-volume aerosol sampler in urban center of Beijing. Nine heavy metals, namely As, Cd, Co, Cr, Cu, Ni, Pb, V, and Zn were determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Then, cancer and non-cancer risks of the residents aging from 1 to 80 were assessed with Chinese exposure factors by using risk evaluation model provided by the Environmental Protection Agency of the United Stated (US. EPA). Results showed that Zn, Pb and Cu were the most abundant elements in PM_2.5, with concentrations of (291 ±553)ng/m³, (53.6 ±73.5)ng/m³ and (25.0 ±59.7)ng/m³ respectively. Among these metals, arsenic had the highest cancer risk contribution (62.5%); while Co had the highest non-cancer risk contribution (29.0%). Hazard index (HI) of these heavy metals was lower than 1 for different age and sex groups, which showed none non-cancer risk, moreover, HI in childhood was higher than that in adulthood. Total cancer risk of these heavy metals (CR) was in the range of 10^-6~10^-4 for different age and sexes groups and showed no obvious cancer risk, moreover, CR increased with age. In addition, cancer and non-cancer risks associated with female population were all lower than those of males.