兰州沙尘总悬浮微粒中有机污染物的变化及来源  

Variability of characteristics and sources of organic pollutants in the total suspended particles in Lanzhou

作　　者：奚晓霞[1] 白艳[1,2] 孟仟祥[3] 王鑫[1] 佘峰[1] 吴方堃[1] 

机构地区：[1]兰州大学大气科学学院,兰州730000 [2]中国科学院青藏高原研究所,北京100085 [3]中国科学院地质与地球物理研究所气体地球化学重点实验室,兰州730000

出　　处：《兰州大学学报（自然科学版）》2009年第2期36-42,共7页Journal of Lanzhou University(Natural Sciences)

基　　金：国家重大基础研究发展规划项目(2005CB422001);国家自然科学基金项目(40421101,40671024)

摘　　要：比较了2006年春季沙尘天气和非沙尘天气吸附到TSP样品中增塑剂、正构烷烃、多环芳烃(PAHs)、甾烷和藿烷类等有机污染组分特征.显示兰州TSP中增塑剂等的工业污染相当严重,煤和生物质燃烧排放以及交通排放较高.非沙尘天气时,污染物主体主要来源于交通排放藿烷和化石燃料燃烧产物释放(煤和生物质燃烧排放为主)的PAHs;而沙尘天气时,虽然兰州地区气体颗粒物急剧增多,但由于有机污染物被沙尘暴带到东部地区,这些有机物质量分数都明显降低.在非沙尘天气,可能是由于沙尘暴源区和沿途土壤高等植物蜡质的风成输入,生物来源的正构烷烃贡献相对增加,其中5个oxy-PAHs和邻苯二甲酸二异壬酯在大气环境研究中很少报道.Six solvent extractable organic compounds were analyzed using GC/MS techniques to compare the characteristics of organic pollutants during the dust-storm days and the non-DSDs in 2006. The preliminary results show that samples of both categories contained plasticizers, n-alkanes, polycyclic aromatic hydrocarbons （PAHs）, oxy-PAHs, and minor amounts of terpanes and steranes. Diagnostic ratios of PAH indicate that the PAHs derived mainly from coal or biomass burning, whereas hopanes came more from traffic emissions. During the observed DSDs, OPs absorbed onto these TSP samples decreased sharply, suggesting that local emissions contributed greatly to the organic contamination in Lanzhou. The dust storms appeared to clear out the contaminants through deposition of the particulates or their transport to more eastern regions. Additional input from the source areas or the storm pathways resulted in greater input of biogenic n-alkanes than on non-DSDs. These results help to better understand the sources and relative contributions of local versus long-range transport of desert dust intrusions. Few previous studies have reported on the occurrence of these five oxy-PAHs and di（2-ethylnonyl） phthalates in the atmosphere.

关 键 词：总悬浮微粒 PAHS oxy—PAHs 甾烷和藿烷 污染源 兰州 

分 类 号：X131[环境科学与工程—环境科学]