郑州市大气PM2.5中重金属的污染特征、来源及健康风险评估:基于高分辨数据

为了研究城市大气PM_2.5中重金属的污染特征和来源，于2017年的7月和10月及2018年的1月和4月，利用在线金属分析仪对郑州市大气PM_2.5中的21种元素进行在线检测，分析了重金属浓度变化；通过富集因子、主成分分析和潜在源贡献等方法对重金属进行溯源；采用环境健康风险评价模型评估其健康风险.结果表明，K、 Zn、 Mn、 Pb、 Cu、 As、 Cr和Se的浓度随污染等级的提高而增加；富集因子和主成分分析法结果表明，重金属主要来源为地壳源、混合燃烧源、工业源和机动车源；雷达特征图表明，地壳源主导的污染主要发生在春、冬两季，混合燃烧源主导的污染主要发生在冬季；Pb、 As和Ni受汾渭平原、京津冀和河南南部的传输影响较大，Cd受采样点西北部影响较大；As对成年人和儿童均有显著致癌风险，Pb和Sb对儿童存在显著非致癌风险.

Pollution Characterization, Source Identification, and Health Risks of Atmospheric Particle-Bound Heavy Metals in PM2.5 in Zhengzhou City: Based on High-resolution Data

In order to study the pollution characteristics and sources of heavy metals in urban atmospheric PM_2.5, 21 elements in atmospheric PM_2.5 in Zhengzhou City were detected using an online metal analyzer during July and October 2017 and January and April 2018, and the changes in heavy metal concentrations were analyzed. Heavy metals were traced by enrichment factors, principal component analysis, and potential source function. The US EPA risk assessment model was used to assess their health risks. The results showed that:the concentrations of K, Zn, Mn, Pb, Cu, As, Cr, and Se increased with the increase in pollution level. The results of enrichment factors and principal component analysis showed that the main sources of heavy metals were crust, mixed combustion, industry, and motor vehicles. The characteristic radar charts showed that the pollution dominated by crustal sources mainly occurred in spring and winter, whereas the pollution dominated by mixed combustion sources mainly occurred in winter. Pb, As, and Ni were greatly affected by the transport of a fen nutrient-laden plain, Beijing-Tianjin-Hebei, and southern Henan, whereas Cd was greatly affected by the northwest region of the sampling site. As presented a significant carcinogenic risk in both adults and children, whereas Pb and Sb presented a significant non-carcinogenic risk in children.