Determination of Radioactivity Levels in the Virgin and Fertilized Soil Samples of Rawalpindi District, Pakistan

摘要

The existence of primodial radionuclides in the earth's crust causes all soils to contain some amount of radioactivity. To increase the crop production, fertilizers are extensively used, which causes further increase in the radioactivity. In order to assess the increase in radioactivity level due to fertilizer, twenty eight (28) soil samples of virgin and fertilized soils from three tehsile of district Rawalpindi, were analyzed using Gamma-Ray Spectroscopy (HPGe) technique. In virgin samples an average activity concentration of 19.04 +/- 1.17 Bq kg(-1) for Ra-226, 32.52 +/- 2.09 Bq kg(-1) for Th-232 and 303.09 Bq kg(-1) for K-40 were found, respectively. In the fertilized soil samples activity concentrations were found to be 20.88 +/- 1.28 Bq kg(-1) for Ra-226, 32.65 +/- 2.01 Bq kg(-1) for Th-232 and 332.35 Bq kg(-1) for K-40, respectively. Only a minor increase in the activity concentration of fertilized samples was noted. Hazard Indices were also calculated for virgin and fertilized soil samples. In both types of samples values of the indices were found to be within permissible limits. The results obtained in current study were compared with the results for other countries