湖南省典型城市 PM10和 PM2.5及其载带重金属的污染特征和健康风险研究

摘要

To investigate the pollution characteristics and health risks of heavy metals in particulate matter in Changsha, Zhuzhou, Xiangtan (CTZ) area in Hunan Province, PM10 and PM2.5 filter samples were collected in Changsha, Xiangtan and background site of Hengshan Mountain in August 2014.The concentrations of ten heavy metals were analyzed by inductively coupled plasma mass spectrometry.In order to assess the carcinogenic risk of Cr(Ⅵ) on human, Cr(Ⅵ) concentrations were calculated based on the reference ratio of 0.13 for Cr(Ⅵ) to total Cr.The health risk of heavy metals inhaled by respiratory system was assessed by the model recommended by US EPA, coupled by the exposure factors in China.Results showed that the mass concentration of PM10 and PM2.5 were respectively 42-155 and 18-119 μg/m3 in Changsha, and were 17-127 and 5-109 μg/m3 in Xiangtan.The concentration of Cr(Ⅵ) in Changsha and Xiangtan was 0.81 and 0.65 ng/m3 in PM10 samples, while that of As was 9.3 and 6.3 ng/m3 , much higher than the relevant Chinese air quality standards.The total non-carcinogenic risk of the each heavy metal was less than 1, within the acceptable level.The carcinogenic risks for Cr(Ⅵ) and As were in the range of 10-6-10-4 , belonging to the range of potential carcinogenic risks.The carcinogenic risks for Cd, Ni and Co were below 10-6 , indicating that the carcinogenic risks of the three metals are acceptable.%为研究湖南省长株潭区域典型城市颗粒物及其载带重金属元素的污染特征和健康风险，于2014年8月在长沙市、湘潭市和区域背景点衡山采集了PM10和PM2.5样品。应用ICP-MS分析样品载带的10种重金属元素浓度，按Cr（Ⅵ）和总Cr比值为0.13估算Cr（Ⅵ）浓度。应用US EPA风险评价技术结合国内人群暴露参数对人体通过呼吸途径暴露的健康风险进行评价。结果表明：采样期间，长沙市PM10和PM2.5的日均浓度分别为42～155和18～119μg/m3，湘潭市为17～127和5～109μg/m3。长沙市和湘潭市PM10载带Cr （Ⅵ）浓度分别为0.81和0.65 ng/m3，As浓度为9.3和6.3 ng/m3，均超过国家重金属年均标准限值。10种重金属元素对暴露人群的非致癌风险都小于1，在可接受范围内。 Cr（Ⅵ）、As的致癌风险为10－6～10－4，有潜在致癌风险；Cd、Ni和Co的致癌风险小于10－6，在人群可接受致癌风险范围内。