云南5城市道路扬尘PM2.5中重金属含量表征及健康风险

为研究云南城市道路扬尘PM_2.5中重金属含量、来源和其健康风险，分别在昆明、保山、文山、昭通和玉溪这5个典型城市区域采集道路扬尘样品，使用颗粒物再悬浮技术将尘样悬浮并采集PM_2.5,利用ICP-MS检测PM_2.5中铬(Cr)、锰(Mn)、镍(Ni)、铜(Cu)、锌(Zn)、砷(As)、镉(Cd)和铅(Pb)等8种重金属.结果表明，5城市道路扬尘Cr、 Ni、 Cu、 Zn和Pb含量均严重超过云南土壤背景值；富集因子表明，云南5城市道路扬尘PM_2.5中重金属多数表现为中度富集和强烈富集，受人为活动影响较大.相关性分析和主成分分析结果表明，云南省不同类型城市道路扬尘PM_2.5中重金属均受土壤源和交通源影响；其余来源差异性较大：昆明受钢铁冶炼源影响、保山和玉溪受有色金属冶炼源影响、昭通受燃煤源影响.健康风险分析表明：昆明、玉溪和昭通的道路扬尘PM_2.5中Cr、 Pb和As存在儿童非致癌风险，昆明市的Cr还存在终身致癌风险.

Characterization and Health Risk of Heavy Metals in PM2.5 from Road Fugitive Dust in Five Cities of Yunnan Province

In order to study the contents, sources, and health risk of PM_2.5 in road fugitive dust in Yunnan, road fugitive dust samples were collected from five typical cities including Kunming, Baoshan, Wenshan, Zhaotong, and Yuxi. Particulate matter resuspension technology was used to levitate the dust samples and collect PM_2.5. Eight heavy metals including chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn), selenium (As), cadmium (Cd), and lead (Pb) in PM_2.5 were detected using ICP-MS. The results showed that the contents of Cr, Ni, Cu, Zn, and Pb in road fugitive dust seriously exceeded the background values of Yunnan soil. The enrichment factors showed that most of the heavy metals in PM_2.5 of road fugitive dust in the five cities of Yunnan were moderately enriched and strongly enriched, which were greatly influenced by human activities. The results of correlation analysis and principal component analysis showed that the heavy metals in PM_2.5 of road fugitive dust in Yunnan were all affected by soil and traffic sources. The other sources varied greatly in different cities:Kunming was affected by iron and steel melting sources, Baoshan and Yuxi were affected by non-ferrous metal smelting sources, and Zhaotong was affected by coal sources. Health risk analysis showed that Cr, Pb, and As in road fugitive dust PM_2.5 had non-carcinogenic risk in children in Kunming, Yuxi, and Zhaotong, respectively, and Cr in Kunming also had a lifetime carcinogenic risk.