兰州市大气降尘中PAHs主要来源及其分布特征

对兰州市春季不同功能区大气降尘有机质中PAHs种类的分析,检出了大气降尘中有机质USEPA优控PAHs有11种以上,含量较高的萘、荧蒽、菲、芘、,占各采样点PAHs总量的70%以上。源解析表明,兰州市各功能区大气降尘中PAHs来源不仅有较高的燃煤源、交通源(汽车尾气),同时PAHs的组成与分布也在很大程度上受到采样点周围居民居住环境的影响。

Distribution and Sources of Priority Polycyclic Aromatic Hydrocarbons(PAHs) in Dustfall at Lanzhou

Organic analyses were carried out for dustfall samples after heating period at Lanzhou by GC-MS measurements. 11 kinds of priority Polycyclic Aromatic Hydrocarbons in dustfall in Lanzhou were detected. The concentrations of NAP,FLUA,PHE,PYR and CHR were higher than others. The percentage of NAP,FLUA,PHE,PYR and CHR to ΣPAH₁₁ was more than 70% in respective samples. The result showed that coal combustion was not the only predominant source,the source of vehicle emissions was important more and more these years. The concentrations and distribution of PAHs in dustfall were influenced strongly by sampling locations and environment around them.