Radiometric Assessment of Farm Soils and Food Crops Grown in Kuru-Jos, Nigeria

Human activities, such as mining, result in the elevation of natural ionizing radiation in the environment. Jos-Plateau, Nigeria, including Kuru-Jos has experienced commercial tin mining in the past, and local mining is still being practiced in this area. Therefore, it is important to assess the radiation exposure due to grown crops and the farm soils in Kuru-Jos, Nigeria. In total, four crops and soil samples were randomly collected from farmlands in Kuru-Jos. The radioactivity levels in the soil and food samples were measured using a thallium-activated sodium-iodide detector coupled to a Canberra series 10 plus Multi-Channel Analyzer. The effective dose rates in soils and food crops along with the cancer risks in the crops were determined. According to the results, the highest mean activity concentrations of 40K, 226Ra, and 232Th in the food crops were 456±126.0Bq/Kg (yam), 46.9±9.6Bq/kg (yam), and 31.6±23.9Bq/Kg (maize), respectively. Moreover, the mean activity concentrations of 40K, 226Ra, and 232Th in farm soil were determined at 1105.6±357.7Bq/Kg (cassava), 167.5±37.6Bq/Kg (yam), and 205.4±124.4Bq/Kg (Guinea corn), respectively. Additionally, yam crop had the highest mean ingestion effective dose of 1231.9µSv/y, and maize crop indicated the minimum mean value of 304.1±179.1µSv/y. The cancer risks of and for yam and cassava, respectively, were higher than the world average value (i.e., 1.0x10-3). The results indicated a high radioactivity level which is in line with the results obtained from other areas in Jos-Plateau, Nigeria; however, there have been no radiological health plague reports from the areas so far.