Natural Radioactivity and Radiation Dose Estimation in Various Water Samples in Abua/Odua Area, Rivers State, Nigeria

Abstract

Gamma spectroscopy was used to determine the activity concentration of 238U, 232Th and 40K and radiation dose estimates in water resources of Abua/Odual Local Government Area in Rivers State of Nigeria. A total of 19 water samples (7 borehole water, 6 river water and 6 hand dug well) were collected from 7 districts of Abua/Odua area. The concentration of 238U, 232Th and 40K were measured by direct counting using sodium iodide [NaI(Ti)] detector interphased with a multi channel analyzer (MCA). The maximum activity concentration of 238U in borehole water, river and hand dug well were 11.58, 2.12 and 26.27 Bql-1 respectively. The mean activity concentration of 232Th in borehole water, river and hand dug well water were 46.21, 8.44 and 66.27 Bql-1 respectively while the activity concentration of 40K in borehole water, river and hand dug well water were 39.22, 47.47 and 609.8 Bql-1 respectively. The mean activity concentration of 40K is higher than 238U and 232Th in all the water samples. The committed effective dose was calculated for infants and adults population of the area. The mean committed effective dose for infants and adults that utilize borehole water were 3.21 and 10.25 mSvy-1 respectively. For infant and adult that use river water, the committed effective doses were 1.13 and 2.14 mSvy-1 respectively while those that consume hand dug well water were 3.11 and 7.36 mSvy-1 respectively. The doses estimated from the activity concentrations of radionuclide showed values within safe limits. Therefore, utilization of the water resources studied would not endanger the lives of the final users.