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

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.