Indoor/outdoor relationship of trace metals in the atmospheric particulate matter of an industrial area

Present study is based on the measurement and monitoring of indoor and outdoor atmospheric particulate matter from an industrial area (Wah Cantt, Pakistan). The particulate samples are collected on glass fiber filter paper using high volume air sampler. Trace metals (Cd, Co, Cr, Cu, Fe, Mn, Pb, Sb and Zn) in the particulate samples are estimated by atomic absorption spectrometry. On the average TSP level is significantly higher in outdoor atmosphere than indoor, and both of them are higher than WHO and USEPA standards. The distribution of trace metals is considerably diverse in indoor and outdoor particulates. Average concentrations of Fe, Zn, Co, Cr and Mn are significantly higher in outdoor particulates, whereas Cu and Pb levels are considerably higher in the indoor particulates. Source apportionment carried out by PCA and CA is diverse in indoor/outdoor particulates and the major pollution sources identified are industrial activities, automobile emissions and soil derived dust. Among the trace metals, Cd, Sb, Zn, Pb and Co are found to be highly enriched in the atmospheric particulate matter. The present atmospheric trace metals levels are also compared with those reported from other regions around the world, and are many-folds higher than previously reported results. (C) 2011 Elsevier B.V. All rights reserved.