Natural radionuclide and radiological impact assessment of teak plantation, University of Ilorin, Kwara State

The amount of naturally occurring radionuclide in Teak plantation was measured using gamma ray spectrometer RS-125. This device gave an in-situ measurement of radioactivity concentration of 40 K, 232 Th, 238 U and dose rate. The data was taken in 20 locations, the overall mean dose rate (DR) is 47.8150 Gyh −1 . The overall mean activity concentrations for 40 K, 232 Th, 238 U are 456.1975 BqKg −1 , 29.0245 BqKg −1 and 26.2080 BqKg −1 respectively. It was also observed that only the estimated outdoor dose rate D of 40 K at study location L1 exceeded the world limit of 57nGyh −1 . This could be due to its closeness to the university main gate with lots of possible interfering human activities around the gate area. However, further study on detailed geochemical investigation is required to reach at some conclusion. By comparing the mean values of the activity concentrations and their radiological risks with the several world standards, it can be concluded that the Teak plantation is highly rich in Potassium.