Assessment of Radiological Doses from the Presence of 226Ra, 232Th and 40K in the Soil Samples of Nawanshahar and Rupnagar Districts of Punjab (India)

Abstract

Apart from Uranium (238U), other natural radionuclides such as radium (226Ra), thorium (232Th) and potassium (40K) are considered to be carcinogenic due to their major contribution of radiological doses to human beings. This study revealed the measurement of primordial radionuclides (226Ra, 232Th, 40K) from the Nawanshahar and Rupnagar districts of Punjab by using a gamma beta spectrometer. The activity concentration of 226Ra, 232Th and 40K in the studied region was ranged from 18 ± 5 Bq kg-1 to 37 ± 6 Bq kg-1, 23 ± 5 Bq kg-1 to 54 ± 8 Bq kg-1 and 273 ± 23 Bq kg-1 to 472 ± 37 Bq kg-1 respectively. The distinct radiation hazards parameters as radium equivalent (RaEq), absorbed dose rate (AD) and annual effective doses (AEDE) were estimated for radiological risk assessment. The absorbed dose levels of 226Ra, 232Th and 40K in the studied area ranged from 8.74 nGyh-1-15.33 nGyh-1, 14.6 nGyh-1-33.7 nGyh-1, and 11.31 nGyh-1 -18.93 nGyh-1, respectively. The annual effective doses in the studied region were 0.32 mSv y-1 (indoor) and 0.8 mSv y-1 (outdoor), respectively. The estimated hazard indices in the studied region were below unity showing that exposure to natural radionuclides in the soil is not a problem in the areas from a radiation hazards point of view.