Assessing the Radiological Health Impact of Soil Used for Agriculture, Federal Polytechnic Ile-Oluji Research Farm

Abstract

This study aims to measure the natural radioactivity concentration of the agricultural soil of the Federal Polytechnic Ile-Oluji research farm using a well-calibrated Camberra NaI (TI) gamma-spectroscopy detector. In addition, the radiological hazard was calculated to evaluate the health impact due to exposure of humans. Twenty (20) soil samples were randomly collected from the agricultural farmland within an area mapped out for the study. The radionuclides of interest in this study are 238U, 232Th, and 40K, respectively. The average activity concentration values of 40K, 238U and 232Th in the soil samples were 475.13 Bq/kg, 55.11 Bq/kg and 42.85 Bq/kg, respectively. Also, the mean value for the radiological hazard indices was for absorbed dose (71.16 nGy/h), outdoor and indoor annual effective dose (0.09 mSv/y and 0.21 to 0.50 mSv/y), external and internal radiation hazard indices (0.41 and 0.56) and radium equivalent activity index (152.98). While gamma index, annual gonadal dose equivalent and excess lifetime cancer risk were 1.11, 498.61 µSv/y and 1.53 X 10-3, respectively. Most radiological parameters calculated for the soil samples of this study are higher than the recommended values for safe soil used for agricultural purposes given by the International Atomic Energy Agency. Thus, environmental monitoring of the study area is highly recommended.