2016-2017年乌鲁木齐市大气细颗粒物中部分金属含量及其污染特征分析

Analysis on Metal Content and Its Pollution in Atmospheric Fine Particles in Urumqi

目的了解乌鲁木齐市近年来大气细颗粒物中部分金属污染现状,为大气污染防制提供科学依据。方法 2016-2017年利用大流量采样器在乌鲁木齐市共采集有效大气细颗粒物样品492份,对颗粒物中部分金属含量及其污染现状进行分析。结果 2016-2017年乌鲁木齐市所测细颗粒物中铝、铅和镉的质量浓度分别为172. 84(96. 76～256. 58) ng/m3、28. 33(16. 66～43. 67) ng/m3和0. 680(0. 354～1. 113) ng/m3。铝、铅、镉的质量浓度呈现季节性变化。乌鲁木齐市2016与2017年所测大气细颗粒物中铝的质量浓度差异有统计学意义(P<0. 01)。铅、镉的质量浓度与日均湿度、日均风速、日均温度的|r|值为0. 622～0. 820。铅、镉的富集因子值均小于1。结论铝、铅、镉的浓度与季节、细颗粒物质量浓度、气象因素等有关联。细颗粒物中铅、镉的富集程度为最小富集。

Objective To understand the metal content and its pollution in atmospheric fine particles in Urumqi in recent years and provide some scientific references for the air pollution control and prevention. Methods A total of 498 effective samples of atmospheric fine particles were collected in Urumqi from 2016 to 2017 by using a large flow sampler. The metal content and its pollution were analyzed based on the samples. Results The mass concentrations of aluminum,lead and cadmium in fine particulates measured in Urumqi from 2016 to 2017 were172. 84( 96. 76 ~ 256. 58) ng/m3,28. 33( 16. 66 ~ 43. 67) ng/m3 and 0. 680( 0. 354 ~ 1. 113) ng/m3,respectively. The mass concentration of aluminum,lead and cadmium changed seasonally. There was a statistically significant difference in the mass concentration of aluminum in atmospheric fine particles measured in Urumqi between 2016 and 2017( P < 0. 01). The mass concentration of lead and cadmium and the daily average humidity,daily average wind speed,and daily average temperature had the | r | value ranged from 0. 622 to0. 820. The enrichment factor values of both lead and cadmium were less than 1. Conclusion The concentrations of aluminum,lead and cadmium are related to the season,fine particles mass concentration,meteorological factors etc. The enrichment of lead and cadmium in fine particles is the minimum.