Shah Munir H, Shaheen N, Jaffar M
Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.
Environ Monit Assess. 2006 Mar;114(1-3):573-87. doi: 10.1007/s10661-006-4940-6. Epub 2006 Mar 30.
To understand the metal distribution characteristics in the atmosphere of urban Islamabad, total suspended particulate (TSP) samples were collected on daily 12 h basis, at Quaid-i-Azam University campus, using high volume sampler. The TSP samples were treated with HNO(3)/HClO(4) based wet digestion method for the quantification of eight selected metals; Fe, Zn, Pb, Mn, Cr, Co, Ni and Cd by FAAS method. The monitoring period ran from June 2001 to January 2002, with a total of 194 samples collected on cellulose filters. Effects of different meteorological conditions such as temperature, relative humidity, wind speed and wind direction on selected metal levels were interpreted by means of multivariate statistical approach. Enhanced metal levels for Fe (930 ng/m(3)), Zn (542 ng/m(3)) and Pb (210 ng/m(3)) were found on the mean scale while Mn, Cr, Co and Ni emerged as minor contributors. Statistical correlation study was also conducted and a strong correlation was observed between Pb-Cr (r=0.611). The relative humidity showed some significant influence on atmospheric metal distribution while other meteorological parameters showed weak relationship with TSP metal levels. Regarding the origin of sources of heavy metals in TSP, the statistical procedure identified three source profiles; automobile emissions, industrial/metallurgical units, and natural soil dust. The metal levels were also compared with those reported for other parts of the world which showed that the metal levels in urban atmosphere of Islamabad are in exceedence than those of European industrial and urban sites while comparable with some Asian sites.
为了解伊斯兰堡市区大气中的金属分布特征，在真纳大学校园使用大容量采样器，每天12小时采集一次总悬浮颗粒物（TSP）样本。采用基于HNO(3)/HClO(4)的湿消化法处理TSP样本，通过火焰原子吸收光谱法（FAAS）对8种选定金属（铁、锌、铅、锰、铬、钴、镍和镉）进行定量分析。监测期从2001年6月至2002年1月，共在纤维素滤膜上采集了194个样本。通过多元统计方法解释了不同气象条件（如温度、相对湿度、风速和风向）对选定金属含量的影响。在平均水平上发现铁（930 ng/m(3)）、锌（542 ng/m(3)）和铅（210 ng/m(3)）的金属含量有所增加，而锰、铬、钴和镍的贡献较小。还进行了统计相关性研究，观察到铅与铬之间存在强相关性（r = 0.611）。相对湿度对大气金属分布有一些显著影响，而其他气象参数与TSP金属含量的关系较弱。关于TSP中重金属的来源，统计程序确定了三种源剖面：汽车排放、工业/冶金单位和天然土壤灰尘。还将这些金属含量与世界其他地区报告的含量进行了比较，结果表明，伊斯兰堡市区大气中的金属含量超过了欧洲工业和城市地区的含量，而与一些亚洲地区相当。
