An Assessment of Absorbed Dose and Radiation Hazard Index from Natural Radioactivity in Soils from Akwa Ibom State, Nigeria

An assessment of Absorbed Dose Rate and Radiation hazard Index from Natural Radioactivity in Soils from Eastern Obolo, Eket, Ibeno, Ikot Abasi and Uyo local government area of Akwa Ibom state was carried out. The levels of naturally occurring radioactivity in the soil samples were evaluated using NaI (Tl) Model 802 Gamma Ray Spectrometer: The mean concentration of 238 U were respectively 11.93±1.63, 8.91±1.39, 21.78±2.32, 12.42±1.63 and 12.13±1.98 Bq.kg -1 . The mean concentration of 232 Th were respectively 14.75±0.70, 18.96±0.62, 21.47±0.76, 12.76±0.75 and 19.09±0.71 Bq.kg -1 .The mean concentration of 40 K were respectively 136.86±3.66, 56.82±3.01, 62.34±3.33, 76.16±3.24 and 67.37±3.29 Bq.kg -1 . The Absorbed Dose Rate, Eternal Hazard Index and Internal Hazard Index were calculated using the activity concentrations of 238 U, 232 Th and 40 K and the mean values obtained were respectively 20.45, 18.26, 25.99, 16.86, 20.27 nGy.h -1 ; 0.17, 0.10, 0.15, 0.21, 0.10 Bq.kg -1 and 0.26, 0.13, 0.21, 0.13, 0.15 Bq.kg -1 . The obtained values were less than the recommended safety limits of 51 nGy.h -1 and 1 Bq.kg -1 .