Evaluation of radionuclides and decay simulation in a terrestrial environment for health risk assessment

This study is to assess the natural radioactivity level in soil samples in communities bordering the Tano Basin in Ghana. The radioactivity concentration of 238 U, 232 Th and 40 K have been determined using γ-ray spectrometry, moreover, the absorbed dose rates and annual effective dose were calculated. MATLAB R2013 script was written to simulate the decay of the radionuclides 238 U, 232 Th and 40 K using their respective half-lives. This is to determine the future impact of natural radionuclides and estimate future anthropogenic inputs. The level 238 U, 232 Th, and 40 K ranged from (1.60 to 21.3), (2.78 to 32.2) and (111 to 528) with average values of be 8.65 Bqkg −1 , 12.5 Bqkg −1 and 214 Bqkg −1 respectively in soil. The activity concentrations were lower than United Nations Scientific Committee on the Effects of Atomic Radiation guidelines for 238 U, 232 Th and 40 K. The absorbed dose rates and annual effective dose were found to be in range of 7.79 to 37.8 nGy h −1 and 9.56E + 00 to 4.64E + 01 µSvy −1 respectively. The overall annual effective dose was lower than the allowable limit of 1mSvy −1 set by International Commission on Radiological Protection . H ex , H in and excess lifetime cancer risk (ELCR) were calculated and found to be within internationally recommended values.