Evaluation of the Activity Concentration of ^40K, ^226Ra and ^232Th in Soil and Associated Radiological Parameters of Shanono and Bagwai Artisanal Gold Mining Areas, Kano State, Nigeria

Mining in the studied area is carried out without any precautionary measure. The radiological implication of this activity was reported in this work. Soil samples were collected from the gold mines and analyzed for activity concentration of naturally occurring radioactive materials (NORMs) using NaI (Tl). The average specific activity of ^238U, ^232Th and ^40K were 62.73, 90.66 and 411.27 Bq/kg respectively. The radiological parameters D (nGy/h), AED (mSv/y) and Ra_eq had average values of 100.89, 0.13 and 224.04 respectively. Furthermore, the radiological hazard indices H_ex, H_in, I_γ and I_α had average values of 0.61, 0.78, 0.86 and 0.31 respectively, which were lower than the United Nations Scientific Committee on effects of atomic radiation (UNSCEAR) recommended limit of unity. Finally, the total cancer risk due to NORMs in soil was 7.35 × 10^-6 for the whole populations which was within the USEPA acceptable range of 1.00 × 10^-6 to 1.00 × 10^-4. Therefore, the gold mining activity poses no significant radiological hazard to the members of the public.