Assessment of radioactivity in the soil samples from Al Bayda city, Libya, and its radiological implications

Abstract

The radioactivity concentration of the terrestrial radionuclides (²³⁸U, ²³²Th, and ⁴⁰K) have been determined in soil samples collected from eight  different locations around of Al Bayda city, Libya, using  the sodium iodide (NaI) detector. Radioactivity concentrations for these elements were estimated and calculated at 0-10 cm depth, we found that an average values of 64.27 Bq/kg, 65.38 Bq/kg and 157.01 Bq/kg, respectively. As well as the radiological hazards were investigated at the same depth, it was found that the radium equivalent (Ra_eq) with an average value of 169.85 Bq/kg and the average values for external and internal hazard indices were 0.46 and 0.63, respectively. While, the average values for Gamma and Alpha indices were 0.32 and 0.60, respectively.

In addition, this study was conducted  at a depth of 10-20 cm, and the average value of uranium was for ²³⁸U, ²³²Th and ⁴⁰K, were an average values of 63.76 Bq/kg, 57.89 Bq/kg, and 253.524 Bq/kg, respectively, and the radium equivalent (Ra_eq) with an average value of 166.06 Bq/kg, and the average values for external and internal hazard indices were 0.45 and 0.62, respectively.The values of Alpha and Gamma indices with average values of 0.32 and 0.59, respectively.

The average activity concentrations of the radionuclides were compared with Global average value where some values were higher than them. The radiological hazard indices of primitive radionuclides were also calculated and it was within the internationally permitted limits.