The effect of air mass origin on the ambient concentrations of 7Be and 210Pb in Islamabad, Pakistan

Concentration of radionuclides Pb-210 and Be-7, having half lives of 22.3 years and 53.29 days, respectively, in the surface air samples of Islamabad (33.38 degrees N, 73.10 degrees E and Altitude similar to 536 m asl.) are measured. The non-destructive technique of gamma-spectrometry, with a high purity germanium HPGe detector, was employed for the analysis of all samples. The annual average concentrations of Pb-210 and Be-7 in the surface air samples were determined as 0.284 +/- 0.15 and 3.171 +/- 1.14 mBq m(-3), respectively. Our results have shown a seasonal variation of the concentration of 7Be in air samples with high values for the spring season. High concentrations for Pb-210 are obtained when air masses originate from plain areas of Pothohar region, located in the South-West, West and North West of Islamabad. Our values of concentrations show a nice agreement with the relevant reported results. (C) 2010 Elsevier Ltd. All rights reserved.