Assessment of radionuclides concentration and associated risks in soils from Iperindo mining sites, Nigeria

Abstract The environmental and health implications of artisanal gold mining activities in mining sites across Nigeria have rekindled research interests. This study aims to assess the scalability of Naturally Occurring Radioactive Materials in gold mining sites in Iperindo, Nigeria. Soil samples were collected from three different mining sites and control locations, and analyzed for natural radionuclides, mainly 238U, 232Th, and 40K using gamma spectrometry having Sodium Iodide detector. The average activity concentration values of 61.55 ± 3.71, 72.65 ± 4.45, 1134.99 ± 38.12 Bqkg− 1 obtained from within the mining sites for 238U, 232Th, and 40K, respectively were above the world permissible values of 33.0 Bqkg− 1 for 238U, 45.0 Bqkg− 1 for 232Th, and 420.0 Bqkg− 1 for 40K. The average activity concentration value of 15.26 ± 3.19, 21.46 ± 4.27, 381.04 ± 23.36 Bqkg− 1 estimated for 238U, 232Th, and 40K, respectively, for the control location were, however, lower than the global permissible values. The study also evaluated other radiological parameters, such as radium equivalent, dose rate, annual effective dose rate, internal and external hazard indices, alpha and gamma indices, etc. The obtained values were 252.83 Bqkg− 1, 119.98 nGyh− 1, 147.15 mSvy− 1, 0.85 Bqkg− 1, 0.68 Bqkg− 1, 0.31 Bqkg− 1, and 1.89 Bqkg− 1 respectively. With the exception of radium equivalent, external and internal hazard risks, and alpha index, which were significantly lower than the recommended threshold, all the other radiological parameters were higher than recommended global limits.