Pohjola Sanna K, Lappi Maija, Honkanen Markku, Rantanen Leena, Savela Kirsti
Finnish Institute of Occupational Health, Helsinki, Finland.
Mutagenesis. 2003 Sep;18(5):429-38. doi: 10.1093/mutage/geg021.
Particulate matter of vehicle exhaust is known to contain carcinogenic compounds such as polycyclic aromatic hydrocarbons (PAH) and is suggested to increase lung cancer risk in humans. This study examines the differences in diesel and gasoline-derived PAH binding to DNA in a human bronchial epithelial cell line (BEAS-2B). Particulate matter (PM) of gasoline exhaust was collected from passenger cars on filters and semi-volatile compounds on polyurethane foam (PUF). The soluble organic fraction (SOF) extracted from the particles was used to expose the cells and to perform PAH analysis. Gasoline extracts, benzo[a]pyrene (B[a]P) and reference materials (SRM 1650 and 1587) were used to study dose-dependent adduct formation in BEAS-2B cells. The levels of DNA adducts were in good accord with the 10 DNA adduct-forming PAH concentrations analyzed in the extracts. Gasoline extracts, SRM 1650, SRM 1587 and B[a]P formed DNA adducts dose-dependently in BEAS-2B cells. The time-dependent DNA adduct formation of 5.0 micro M B[a]P was lower than that of 2.5 micro M B[a]P. The results of this study indicate that reformulated and standard diesel fuels formed about 11- and 31-fold more adducts than gasoline, respectively, when PAH-DNA adduct levels were calculated on an emission basis (adducts/mg PM/km), whereas on a particulate basis (adducts/mg PM) no difference between the diesel and gasoline extracts was observed. We conclude that the genotoxicity of diesel fuel is based on higher particulate emission rates compared to gasoline emission and although the concentration of PAH compounds was higher in diesel particulate extracts, DNA binding by the gasoline particulate-bound PAH compounds was more pronounced than that by the diesel particulate-bound PAH compounds.
已知汽车尾气中的颗粒物含有多环芳烃（PAH）等致癌化合物，并被认为会增加人类患肺癌的风险。本研究检测了柴油和汽油衍生的PAH在人支气管上皮细胞系（BEAS - 2B）中与DNA结合的差异。从乘用车收集汽油尾气颗粒物，用过滤器收集颗粒物质，用聚氨酯泡沫（PUF）收集半挥发性化合物。从颗粒中提取的可溶性有机部分（SOF）用于处理细胞并进行PAH分析。使用汽油提取物、苯并[a]芘（B[a]P）和参考物质（SRM 1650和1587）研究BEAS - 2B细胞中剂量依赖性加合物的形成。DNA加合物的水平与提取物中分析的10种形成DNA加合物的PAH浓度高度一致。汽油提取物、SRM 1650、SRM 1587和B[a]P在BEAS - 2B细胞中呈剂量依赖性形成DNA加合物。5.0微摩尔B[a]P的时间依赖性DNA加合物形成低于2.5微摩尔B[a]P。本研究结果表明，当以排放为基础计算PAH - DNA加合物水平（加合物/毫克颗粒物/公里）时，新配方柴油和标准柴油燃料形成的加合物分别比汽油多约11倍和31倍，而以颗粒物为基础（加合物/毫克颗粒物）时，柴油和汽油提取物之间未观察到差异。我们得出结论，柴油燃料的遗传毒性是基于其比汽油排放更高的颗粒物排放率，尽管柴油颗粒物提取物中PAH化合物的浓度更高，但汽油颗粒物结合的PAH化合物与DNA的结合比柴油颗粒物结合的PAH化合物更明显。
