2015年兰州市大气细颗粒物成分监测

目的 了解兰州市大气细颗粒物(PM2.5)含量及成分,为大气污染源解析提供依据.方法 于2015年1-12月分别在兰州市城关区和西固区各1个监测点采集大气PM2.5样品84份,分析样品中PM2.5质量浓度及PM2.5中无机水溶性离子、金属元素、多环芳烃含量.结果 城关区大气PM2.5平均质量浓度高于西固区(Z=-3.226,P＜0.01);西固区大气PM2.5中NO3-质量浓度低于城关区,PM2.5中锑、铍、铬的质量浓度高于城关区,镉、汞、铅、锰、镍的质量浓度低于城关区,差异均有统计学意义(P＜0.05);城关区大气PM2.5中16种多环芳烃均值为1.15 ng/m3,西固区大气PM2.5中16种多环芳烃均值为0.95 ng/m3,城关区高于西固区,差异有统计学意义(P＜0.05).结论 2015年兰州市城关区和西固区大气PM2.5污染水平及主要污染成分不同,需有针对性地制定大气污染防控措施.

Components of fine particulate matters in Lanzhou in 2015

Objective To understand the content of fine particles components in air in Lanzhou and to provide the basis for source apportionment of air pollutants.Methods The air samples in two monitoring points,Chengguan district and Xigu district of Lanzhou,were collected in 2015.The content of inorganic elements,water soluble ions and polycyclic aromatic hydrocarbons in PM2.5 were analyzed.Results The level of PM2.5 was higher in Chengguan district than that in Xigu district.The ion component NO3-in PM2.5 was lower in Xigu district than that in Chengguan district.The levels of Ge,Hg,Pb and Mn were higher in Chengguan district than those in Xigu district.The averge level of polycyclic aromatic hydrocarbon was 1.15 ng/m3 in all 16 kinds of polycyclic aromatic hydrocarbons in Chengguan district,which was significantly higher than that (0.95 ng/m3) in Xigu district (P＜0.05).The level of polycyclic aromatic hydrocarbons was higher in Chengguan district than that in Xigu district.Conclusion There is significant difference in pollution levels between Chengguan district and Xigu district in Lanzhou and also the main pollution components.It is very impotent to make apointed preventive and control measures.