Measurement of Ra 226 , Th 232 , Cs 137 and K 40 activities of Wheat and Corn Products in Ilam Province – Iran and Resultant Annual Ingestion Radiation Dose

Background: Background: Natural background radiation is the main source of human exposure to radioactive material. Soils naturally have radioactive mineral contents. The aim of this study is to determine natural ( U 238 , Th 232 , K 40 ) and artificial ( Cs 137 ) radioactivity levels in wheat and corn fields of Eilam province. Methods: HPGe detector was used to measure the concentration activity of U 238 and Th 232 series, K 40 and Cs 137 in wheat and corn samples taken from different regions of Eilam province, in Iran. Results: In wheat and corn samples, the average activity concentrations of Ra 226 , Th 232 , K 40 and Cs 137 were found to be 1,67, 0.5, 91.73, 0.01 and 0.81, 0.85, 101.52, 0.07Bq/kg (dry weight), respectively. Hex and Hin in the present work are lower than 1. The average value of Hex was found to be 0.02 and 0.025 and average value of Hin to be found 0.025 and 0.027 in wheat fields samples and corn samples in Eilam provinces, respectively. The obtained values of AGDE are 30.49 mSv/yr for wheat filed samples and 37.89 mSv/yr for corn samples; the AEDE rate values are 5.28 mSv/yr in wheat filed samples and this average value was found to be 6.13 mSv/yr in corn samples in Eilam. Transfer factors (TFs) of long lived radionuclide such as Cs 137 , Ra 226 , Th 232 and K 40 from soils to corn and wheat plants have been studied by radiotracer experiments. Conclusion: The natural radioactivity levels in Eilam province are not at the range of high risk of morbidity and are under international standards.