Chang Chang-Tang, Chen Bor-Yann
Department of Environmental Engineering, National I-Lan University, I-Lan, 260 Taiwan, ROC.
J Hazard Mater. 2008 May 30;153(3):1262-9. doi: 10.1016/j.jhazmat.2007.09.091. Epub 2007 Sep 29.
This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose-response analysis and margin of safety using Escherichia coli DH5 alpha. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC50, was approximately as follows: PAHs>two-stroke engines>four-stroke engines>BTEX.
本研究通过剂量反应分析和安全边际，利用大肠杆菌DH5α研究了摩托车尾气中各种污染物的毒性。对用冲击式吸收管收集的摩托车尾气挥发性有机化合物（VOCs）以及用过滤器和XAD - 2收集的多环芳烃（PAHs）的主要成分进行毒性评估，对于确定摩托车排放标准至关重要。选择苯（B）、甲苯（T）、乙苯（E）和二甲苯（X）的毒性作为摩托车排放的标准VOCs进行比较。此外，制备了三种类型的新配方汽油（高含氧量和高苯含量（1号）、低氧和高苯（2号）以及低氧和低苯（3号）），以揭示各成分的联合毒性。由于不完全燃烧产生的高毒性VOCs，摩托车尾气的毒性明显高于苯系物（BTEX）。总体毒性评估表明，以半数效应浓度（EC50）表示的毒性大致如下：PAHs＞二冲程发动机尾气＞四冲程发动机尾气＞BTEX。
