Alam Khan, Blaschke Thomas, Madl Pierre, Mukhtar Azam, Hussain Majid, Trautmann Thomas, Rahman Said
Department of Geography and Geology, University of Salzburg, Hellbrunnerstrasse 34, Salzburg, 5020, Austria.
J Environ Monit. 2011 Jul;13(7):1944-52. doi: 10.1039/c1em10086f. Epub 2011 Jun 15.
During March and April 2010 aerosol inventories from four large cities in Pakistan were assessed in terms of particle size distributions (N), mass (M) concentrations, and particulate matter (PM) concentrations. These M and PM concentrations were obtained for Karachi, Lahore, Rawalpindi, and Peshawar from N concentrations using a native algorithm based on the Grimm model 1.109 dust monitor. The results have confirmed high N, M and PM concentrations in all four cities. They also revealed major contributions to the aerosol concentrations from the re-suspension of road dust, from sea salt aerosols, and from vehicular and industrial emissions. During the study period the 24 hour average PM(10) concentrations for three sites in Karachi were found to be 461 μg m(-3), 270 μg m(-3), and 88 μg m(-3), while the average values for Lahore, Rawalpindi and Peshawar were 198 μg m(-3), 448 μg m(-3), and 540 μg m(-3), respectively. The corresponding 24 hour average PM(2.5) concentrations were 185 μg m(-3), 151 μg m(-3), and 60 μg m(-3) for the three sites in Karachi, and 91 μg m(-3), 140 μg m(-3), and 160 μg m(-3) for Lahore, Rawalpindi and Peshawar, respectively. The low PM(2.5)/PM(10) ratios revealed a high proportion of coarser particles, which are likely to have originated from (a) traffic, (b) other combustion sources, and (c) the re-suspension of road dust. Our calculated 24 hour averaged PM(10) and PM(2.5) concentrations at all sampling points were between 2 and 10 times higher than the maximum PM concentrations recommended by the WHO guidelines. The aerosol samples collected were analyzed for crustal elements (Al, Fe, Si, Mg, Ca) and trace elements (B, Ba, Cr, Cu, K, Na, Mn, Ni, P, Pb, S, Sr, Cd, Ti, Zn and Zr). The averaged concentrations for crustal elements ranged from 1.02 ± 0.76 μg m(-3) for Si at the Sea View location in Karachi to 74.96 ± 7.39 μg m(-3) for Ca in Rawalpindi, and averaged concentrations for trace elements varied from 7.0 ± 0.75 ng m(-3) for B from the SUPARCO location in Karachi to 17.84 ± 0.30 μg m(-3) for Na at the M. A. Jinnah Road location, also in Karachi.
2010年3月至4月期间，对巴基斯坦四个大城市的气溶胶清单进行了评估，内容涉及粒径分布（N）、质量（M）浓度和颗粒物（PM）浓度。卡拉奇、拉合尔、拉瓦尔品第和白沙瓦的这些M和PM浓度是使用基于格林模型1.109粉尘监测仪的本地算法，从N浓度中获取的。结果证实了这四个城市的N、M和PM浓度都很高。研究还表明，道路扬尘再悬浮、海盐气溶胶以及车辆和工业排放对气溶胶浓度有主要贡献。在研究期间，卡拉奇三个地点的24小时平均PM(10)浓度分别为461μg/m³、270μg/m³和88μg/m³，而拉合尔、拉瓦尔品第和白沙瓦的平均值分别为198μg/m³、448μg/m³和540μg/m³。卡拉奇三个地点相应的24小时平均PM(2.5)浓度分别为185μg/m³、151μg/m³和60μg/m³，拉合尔、拉瓦尔品第和白沙瓦的分别为91μg/m³、140μg/m³和160μg/m³。较低的PM(2.5)/PM(10)比值表明粗颗粒比例较高，这些粗颗粒可能来自（a）交通、（b）其他燃烧源以及（c）道路扬尘再悬浮。我们计算得出，所有采样点的24小时平均PM(10)和PM(2.5)浓度比世界卫生组织指南建议的最大PM浓度高出2至10倍。对采集的气溶胶样本分析了地壳元素（铝、铁、硅、镁、钙）和微量元素（硼、钡、铬、铜、钾、钠、锰、镍、磷、铅、硫、锶、镉、钛、锌和锆）。地壳元素的平均浓度范围从卡拉奇海景地点的硅的1.02±0.76μg/m³到拉瓦尔品第的钙的74.96±7.39μg/m³，微量元素的平均浓度从卡拉奇SUPARCO地点的硼的7.0±0.75ng/m³到卡拉奇真纳路地点的钠的17.84±0.30μg/m³不等。
