Survey of Natural Radioactivity of Soil and Rock Samples and their Radiological Implications to Human Health in Ugwuele Quarry Mining Site, Uturu, Abia State, Nigeria

Abstract

This work measured the activity concentration of natural radionuclides 238U, 232Th and 40K in soil and rock samples collected in Ugwuele mining site and it surrounding communities in Uturu, Abia state, Nigeria. Fifteen different samples collected were analyzed.  A NaI (Tl) spectrometry detector system was adopted for this research. The results obtained were used to estimate the radiological implication of the quarry mining in the study area.  The average gamma activity obtained for 238U, 232Th and 40K in soil were 53.39 ± 3.08, 76.79 ± 9.66 and 1061.02 ± 15.72 Bq/kg respectively and 55.09 ± 5.71, 90.96 ± 16.10 and 1281.78 ± 6.38 Bq/kg respectively for rock samples. The calculated radiological hazard indices from Absorbed dose rate, Annual effective dose, Radium equivalent, internal hazard index and External hazard index gave 120.25 nGy/h, 0.147 msv/yr, 247.5 Bq/kg, 0.833 and 0.687 respectively. The average dose rate was higher than the recommended limit. Therefore, soil and rock materials found in Ugwuele could increase the radiological hazards on miners and residents of the area due to long time cumulative exposure.