Díaz-Robles L A, Fu J S, Reed G D
School of Environmental Engineering, Catholic University of Temuco, Temuco, Chile.
Environ Int. 2008 Jan;34(1):1-11. doi: 10.1016/j.envint.2007.06.002. Epub 2007 Jul 9.
The fine and ultra fine sizes of diesel particulate matter (DPM) are of greatest health concern. The composition of these primary and secondary fine and ultra fine particles is principally elemental carbon (EC) with adsorbed organic compounds, sulfate, nitrate, ammonia, metals, and other trace elements. The purpose of this study was to use an advanced air quality modeling technique to predict and analyze the emissions and the primary and secondary aerosols concentrations that come from diesel-fueled sources (DFS). The National Emissions Inventory for 1999 and a severe southeast ozone episode that occurred between August and September 1999 were used as reference. Five urban areas and one rural area in the Southeastern US were selected to compare the main results. For urban emissions, results showed that DFS contributed (77.9%+/-8.0) of EC, (16.8%+/-8.2) of organic aerosols, (14.3%+/-6.2) of nitrate, and (8.3%+/-6.6) of sulfate during the selected episodes. For the rural site, these contributions were lower. The highest DFS contribution on EC emissions was allocated in Memphis, due mainly to diesel non-road sources (60.9%). For ambient concentrations, DFS contributed (69.5%+/-6.5) of EC and (10.8%+/-2.4) of primary anthropogenic organic aerosols, where the highest DFS contributions on EC were allocated in Nashville and Memphis on that episode. The DFS contributed (8.3%+/-1.2) of the total ambient PM(2.5) at the analyzed sites. The maximum primary DPM concentration occurred in Atlanta (1.44 microg/m(3)), which was 3.8 times higher than that from the rural site. Non-linearity issues were encountered and recommendations were made for further research. The results indicated significant geographic variability in the EC contribution from DFS, and the main DPM sources in the Southeastern U.S. were the non-road DFS. The results of this work will be helpful in addressing policy issues targeted at designing control strategies on DFS in the Southeastern U.S.
柴油颗粒物（DPM）的细颗粒和超细颗粒对健康危害最大。这些一次和二次细颗粒及超细颗粒的成分主要是元素碳（EC），以及吸附的有机化合物、硫酸盐、硝酸盐、氨、金属和其他微量元素。本研究的目的是使用先进的空气质量建模技术，预测和分析来自柴油燃料源（DFS）的排放以及一次和二次气溶胶浓度。以1999年国家排放清单和1999年8月至9月间发生的一次严重的东南部臭氧事件作为参考。选取了美国东南部的五个城市地区和一个农村地区来比较主要结果。对于城市排放，结果表明，在所选定的时段内，DFS对元素碳的贡献率为（77.9%±8.0），对有机气溶胶的贡献率为（16.8%±8.2），对硝酸盐的贡献率为（14.3%±6.2），对硫酸盐的贡献率为（8.3%±6.6）。对于农村地区，这些贡献率较低。在孟菲斯，DFS对元素碳排放的贡献率最高，主要归因于柴油非道路源（60.9%）。对于环境浓度，DFS对元素碳的贡献率为（69.5%±6.5），对一次人为有机气溶胶的贡献率为（10.8%±2.4），在该时段，纳什维尔和孟菲斯的DFS对元素碳的贡献率最高。在分析地点，DFS对环境中总PM2.5的贡献率为（8.3%±1.2）。一次DPM的最大浓度出现在亚特兰大（1.44微克/立方米），是农村地区的3.8倍。遇到了非线性问题，并提出了进一步研究的建议。结果表明，DFS对元素碳的贡献存在显著的地理差异，美国东南部主要的DPM来源是非道路DFS。这项工作的结果将有助于解决针对美国东南部DFS设计控制策略的政策问题。
