Guo Zhao-Xia, Geng Hong, Zhang Jin-Hong, Zhou Huan, Peng Yan, Zhai Shuai-Ying, Li Jin-Lei, Chen Yu-Shan
Institute of Environmental Science, Shanxi University, Taiyuan 030006, China.
College of Environmental & Resource Sciences, Shanxi University, Taiyuan 030006, China.
Huan Jing Ke Xue. 2018 Mar 8;39(3):1004-1013. doi: 10.13227/j.hjkx.201706011.
The pollution of atmospheric PM and ambient air quality were investigated in Wuxiang Town, Shanxi Province, China, and the ecological and health risks of the trace heavy metals in PM were analyzed. The PM samples were collected every day using a medium-volume PM sampler in autumn (from Oct. 22 to Nov. 19, 2014) and in winter (from Jan. 12 to Feb. 13, 2015) on the roof of a building at the Wuxiang Environmental Protection Agency (EPA). The mass concentrations of PM were determined gravimetrically, and the contents of seven trace heavy metals (i. e., As, Cd, Cr, Cu, Ni, Pb, and Zn) in PM were obtained using Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The pollution extent, sources, and potential ecological and health risks of the trace heavy metals in PM were identified and assessed using the geo-accumulation index, ecological risk index, a correlation and principle component analysis, and the exposure risk models of US EPA. Results showed that the average concentration of PM in winter, approximately three times higher than that in autumn, exceeded the national secondary standard of ambient air quality (GB 3095-2012) on 65% of the sampling days. The heavy metals in PM mainly originated from anthropogenic activities, with contributions of 58.38% and 18.73% from coal combustion and vehicular emission, respectively. In general, the levels of the heavy metals in PM followed the order of Cu > Zn > Pb > Cr > As > Ni > Cd, with higher ecological risks from Cd and Cu and higher non-carcinogenic and carcinogenic risks from Cr compared with other metals. It is suggested that greater coal combustion in winter under the adverse geographical conditions for air diffusion in Wuxiang Town were responsible for the increased atmospheric PM concentration and their ecological and health risks in heavy metals.
对中国山西省武乡镇的大气颗粒物（PM）污染及环境空气质量进行了调查，并分析了PM中痕量重金属的生态和健康风险。在秋季（2014年10月22日至11月19日）和冬季（2015年1月12日至2月13日），每天使用中流量PM采样器在武乡县环境保护局大楼楼顶采集PM样本。通过重量法测定PM的质量浓度，采用电感耦合等离子体原子发射光谱法（ICP - AES）测定PM中7种痕量重金属（即砷、镉、铬、铜、镍、铅和锌）的含量。利用地累积指数、生态风险指数、相关性和主成分分析以及美国环境保护局（US EPA）的暴露风险模型，对PM中痕量重金属的污染程度、来源以及潜在的生态和健康风险进行了识别和评估。结果表明，冬季PM的平均浓度约为秋季的三倍，在65%的采样日超过了国家环境空气质量二级标准（GB 3095 - 2012）。PM中的重金属主要源于人为活动，其中煤炭燃烧和机动车排放的贡献率分别为58.38%和18.73%。总体而言，PM中重金属含量顺序为铜＞锌＞铅＞铬＞砷＞镍＞镉，镉和铜的生态风险较高，铬的非致癌和致癌风险高于其他金属。研究表明，武乡镇冬季煤炭燃烧量大，且处于不利于空气扩散的地理条件下，导致大气PM浓度升高及其重金属的生态和健康风险增加。
