Radiation hazard of naturally occurring soil in FONGO TONGO-Cameroon

Abstract

In the present investigation, natural radioactivity in soil samples from the bauxite ore deposit in FONGO TONGO municipality of Menoua Division, Western Cameroon was assessed using gamma spectrometry. Priory analysis, the detector was calibrated for both energy and efficiency using standard sources. The investigated soil samples of NDIFONDA and APOUH were randomly collected. The observed specific activities of primordial radionuclides in soil from both study areas were comparably higher than the reference values of UNSCEAR, however varied within the exemption levels recommended in the IAEA basics safety standards. The observed average values of radium equivalent activity were 299.58 Bq/kg in NDIFONDA and 425.86 Bq/kg in APOUH. The observe value in APOUH were relatively higher than the recommended save value by ICRP while that of NDIFONDA were lower. Because majority of the houses in the study site are made of brick concrete, radiological health hazard parameters (air-absorbed dose rate (D) and total annual effective dose (ET)) were estimated to evaluate public exposure to natural radiation from soil. The observed values for D and ET were relatively higher than the recommended value of UNSCEAR (143 and 0.48 mSv/year, respectively) in both sites. In addition, the calculated values of excess lifetime cancer risk were slightly higher than the worldwide averages. Finding of this study revealed that long-term exposure to natural radiation in the study area might contribute to some health disease. Therefore, further studies need to be carried out to assess long-term exposure risk to radiation priory exploration of the mine.