NATURALLY OCCURRING RADIONUCLIDES IN SOIL SAMPLES OF BURETI SUB-COUNTY OF KERICHO COUNTY KENYA

摘要

The activity concentration of soil samples of Bureti sub-county was measured using thallium-activated sodium iodide detector. To ascertain the level of radiation hazard to the public, gamma radiation dose rates were also estimated. The average activity concentration due to ~(40)K, ~(226)Ra and ~(232)Th for soil samples are 1164 ± 70, 106 ± 8 and 79 ± 5 Bqkg~(-1), respectively. An average dose rate of 145 ± 10 nGyh~(-1) was recorded, which is about 2.5 times higher than the world average value of 60 nGyh~(-1)(UNSCEAR). On the other hand, an average outdoor effective dose of 0.35 ± 0.02 mSvy~(-1) was measured, which is lower than the ICRP safety limit of 1 mSvy~(-1). This shows that the radiation hazards from naturally occurring terrestrial radionuclides in Bureti is low and therefore human radiation exposure is within the accepted limits.