Radioactivity levels and transfer factor for granite mining field in Asa, North-central Nigeria

Abstract

Natural radioactivity measurement and dose assessment are important aspects of radiation protection. The goal of this study is to validate the previous results obtained from the in-situ measurements in the study area in order to ascertain the level of radiation hazards to the populaces living around the mining site.A3 × 3-inch lead-shielded NaI(Tl) detector was used to measure the activity concentrations of 40K, 238U and232Thin soil, water and guinea corn grain samples collected from a granite mining field in Asa, Kwara State, North-central Nigeria. The overall mean activity concentrations of 40K, 238U and 232Th are 441.06, 11.51 and 15.42 Bqkg−1for the soil samples, 20.67, 0.66, and 0.88 BqL−1 for the water samples and 214.31, 5.25 and 8.86 Bqkg−,1respectively for the grain samples. The bioaccumulation/transfer factors are 0.49, 0.46 and 0.58 for 40K,238U and 232Th respectively. The mean values of all the radiological hazard parameters are within the permissible limit recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation. Consequently, the risk of indoor and outdoor gamma radiation exposure is comparatively less for these Granite soils. Hence, the results in this study will reference future studies in terms of basic radiological data.

Keywords

• Atomic physics
• Environmental science
• Nuclear physics
• Granite
• Asa
• Nigeria