Radiometric Evaluation of Naturally Occurring Radionuclides in Mining Sites across Mararraba-Udege of Nasarawa State, Nigeria

Abstract

This study evaluates the existence of radionuclides in some mining sites in Mararaba-Udege using a hand held interceptor TM–Thermo scientific radio nuclear identiFINDER designed for in situ operation. The device is placed in contact with the soil and the radionuclides in the soil are detected as well as the contribution of those radionuclides to the background radiation. Gamma Activity (mRem/yr), possible radionuclide present and their trust levels, Exposure Dose Rate ($\mu$Sv/hr), Absorbed Dose Rate (nGy/hr), Effective Dose Rates (mSv/yr) and Excess Lifetime Cancer Risk, were determined. Results obtained shows that the gamma activity level ranged from 0.955 to 1.260 mrem/hr with the mean of 1.1245 mrem/hr. Exposure dose rate of the study area ranged from 9.55 to 12.6 $\mu$Sv/hr with the mean of 11.245 $\mu$Sv/hr. The local miners in the study area are subjected to absorb dose rate ranging from 9553 to 12600 nGy/hr with the mean value of 11245 nGy/hr. Effective dose rate of the area under investigation were ranged from 1.605 to 2.117 mSv/yr with a mean of 1.889 mSv/yr. The excess lifetime cancer risk of the area ranged from $5.618 \times 10^{-3}$ to $7.408 \times 10^{-3}$ with the mean of $6.629 \times 10^{-3}$. The result also shows that there is Palladium (${}^{103}$Pd), Americium (${}^{241}$Am), Iodine (${}^{125}$I), Uranium (${}^{235}$U), Cadmium (${}^{106}$Cd), Selenium (${}^{75}$Se) and Cobalt (${}^{57}$Co) in significant percentage. From the findings presented, it can be concluded that natural radionuclides pollution in the mining area is an issue of health concern.