Radiological Evaluation of Soil in Some Selected Oil and Gas Producing Communities in Delta Central, Delta State Nigeria

The radionuclides present in soils from selected oil and gas producing communities in Delta Central, Delta State, Nigeria, were qualitatively and quantitatively determined using gamma-ray spectrometry with a view of evaluating the radiological health hazard fallout of the oil and gas activities in these areas. The results revealed the presence of 238U, 232Th and 40K respectively. The minimum values for these radionuclides activity concentrations are 83.76+4.10, 4.10+0.12 and 1.92+0.09 Bqkg-1 respectively. The corresponding maximum values are 373.02 18.25, 89.49+2.09 and 30.61+1.47 Bqkg-1. Their respective obtained mean values are 180.61+2.79, 44.24+1.53 and 15.58+0.72 Bqkg-1 respectively. It was observed that the activities of 40K and 232Th are higher than that of 238U. The specific activities of 40K and 232Th are below the worldwide average while that of the values obtained from 238U is above standard. These values equally agree with other studies carried out in parts of Nigeria and the world. The high level of 238U concentration in the region may be attributed to oil exploration and exploitation activities in the areas. The calculated mean for the radiological hazard indices revealed Raeq (80.42)Bqkq-1, absorbed dose D (37.95)nGyh-1 (effective dose equivalent value 0.038 mSvy-1), AEDE(outdoor) (53.58) and (indoor) (186.06) mSvy-1, Hex (0.216), Hin (0.336) and finally, ELCR(0.016 x 10-3) respectively. The obtained results are below their respectively international radiological health standards. The implication is that the populace are not radiologically overexposed.