城市秋季大气PM10中的有机污染特征研究--以北京市西北城区为例

使用大流量采样仪在北京西北城区采集了大气中可吸入颗粒物(PM10)样品，利用CCl4和CH4Cl3对样品中的可溶有机物进行萃取分离，结果表明虽然PM10的总质量浓度变化较大，但可溶有机物的质量浓度变化很小。应用气相色谱(GC)，气相色谱／质谱(GC／MS)对可溶有机物中饱和烃、芳烃的组成和分布特征进行了分析。西北城区大气中含有种类繁多的由化石燃料不完全燃烧所产生的饱和烃类污染物，这表明化石燃料不完全燃烧对西北城区大气的污染有很大影响。GC／MS分析还检测出了100多种多环芳烃(PAHs)，其中有10种是属于美国国家环保局(US—EPA)优先控制污染物，怀疑具有致癌性。由机动车排放的苯并k]萤蒽的浓度在这些优先控制污染物中浓度最高，所以由机动车尾气带来的污染也是一个重要方面。

Characteristics of Extractable Organic Matter in PM10 of Urban Area--Case Study of Northwestern Beijing

The airborne particles (PM10) was collected using the high-volume TSP-PM10 sampler (XH1000) in the northwestern urban area of Beijing, the soluble organic matter was extracted with CC14 and CH4Cl3. The result shows that, in the northwestern urban ambient air of Beijing, the mass levels of soluble organic matter are relatively consistent through the sampling period although the PM10 mass levels vary. By using Gas Chromatogram (GO and Gas Chromatogram/Mass Spectrometry (GD/MS), the group compositions and distribution of the saturated hydrocarbons and poly-cyclic aromatic hydrocarbons (PAHs) in the extractable organic matter have been outlined. More than 100 types of the PAHs have been identified, in which 10 types are suspected to be carcinogenic and are the priority-controlled pollutants regulated by Environmental Protection Agency of the United States. It is suggested that the incomplete combustion of the fossil fuel has a strong influence on the organic air pollution of the northwestern urban Beijing area. Moreover , the high bezofluoranthene concentration indicates that the diesel exhaust might be an important organic pollution source in the research area.