亚青会期间南京大气PM_(2.5)中重金属来源及风险

为探究亚青会期间南京奥体中心附近大气PM2.5中重金属来源及潜在的健康风险,于2013年8月3~28日对PM2.5中重金属元素V、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Cd、Sn、Sb和Pb进行了观测分析.结果表明:受亚青会污染源调控和气象要素影响,亚青会前、中、后不同时期重金属浓度存在差异,亚青会期间各重金属的浓度均值低于亚青会前期.富集因子分析显示Cu、Zn、Cd、Sn、Sb和Pb为重度富集元素,污染程度为CdCuZnPbSbSn.聚类分析表明工业排放、燃煤、道路尘和机动车尾气排放是这些重金属的主要来源.亚青会期间,PM2.5中各重金属通过呼吸途径对运动员造成的非致癌风险均小于1,5种致癌重金属的风险指数均低于致癌风险阈值范围.

Sources and risk assessment of heavy metals in ambient PM2.5 during Youth Asian Game period in Nanjing

In order to evaluate the sources and health risks of heavy metals in PM_2.5 around the Youth Asian Game (YAG) period, thirteen heavy elements including V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Sn, Sb and Pb in PM_2.5 were analyzed for a site near the Nanjing Olympic Sport Center during 3~28 August, 2013. Results indicated that the concentrations of heavy metals are different among the pre-, during- and after- YAG period, influenced by both the pollution control regulations and meteorological parameters. Their concentrations are higher for the pre-YAG period than those for during-YAG period. Enrichment factor index indicated that Cu, Zn, Cd, Sn, Sb and Pb are highly enriched elements, with their pollution level decreasing as Cd > Cu > Zn > Sb > Sn > Pb. Cluster analysis implied that industrial emission, coal combustion, road dust and vehicle emissions were the major sources of these heavy elements. During the YAG period, the non-carcinogenic risks raised by heavy elements in PM_2.5 through inhalation pathway are less than 1. The risk indexes of five carcinogenic heavy metals are also lower than the thresholds of cancer risk correspondingly.