Estimation of Radiological Risks in Soils from Selected oil-Spill Communities in the Niger Delta, Nigeria

The estimation of radiological risks in soils from selected oil-spill communities in the Niger Delta, Nigeria has been carried out using Sodium Iodide detector dopped with Thallium based on gamma spectroscopy, NaI(TI)Ɣ, followed by mathematical computations. The activity concentrations of radionuclides of 226Ra, 232Th, and 40K ranged from 25.23±2.30 to 50.12±4.22 Bq/kg, 42.18 ± 4.01 to 60.01±2.30 Bq/kg, and 150.29±8.31 to 210.00±8.18 Bq/kg respectively. Also, the mean values of the activity concentration of radionuclides of 226Ra, 232Th, and 40K were 37.34, 50.72, and 181.57 Bq/kg respectively. The mean values of the annual gonadal dose equivalent (AGDE), representative gamma index, (Iγ), external hazard index (Hex), internal hazard index (Hin), and radium equivalent activity (Raeq) were 384.42 μSv/y, 1.509, 0.334, 0.435, and 123.90 Bq/kg, respectively. The mean of the annual effective doses for infants, children, teenagers, and adults were 32.726x10-3, 26.086x10-3,24.522x10-3, and 23.135x10-3mSv/y respectively. the obtained value was all below the recommended safe limit of 1.0 mSv/y. The corresponding mean of lifetime fatality risks were 37.16 x10-6, 73.98 x10-6, 74.21 x10-6, and 68.13x10-6 for infants, children, teenagers, and adults, respectively. The results indicated that higher estimated risk was recorded within the teenage age group. In general, the results showed that the investigated soil samples do not constitute any significant radiological health hazard under the existing exposure conditions. However, use of high-power germanium detector is recommended for further study