TRANSFER FACTORS FOR ,,THE SOIL-CEREALS SYSTEM IN THE REGION OF PCINJA, SERBIA

The aim of the paper was to estimate the values of transfer factors for natural radionuclides (K-40, Ra-226, Th-232, U-235, and U-238) and Cs-137 from soil to plants (cereals: wheat, corn and barley) as important parameters for the agricultures in the selection of the location and the sort of cereals to be planted on. The results presented in this paper refer to the ,,soil -cereals system in the region of Pcinja, Serbia. Total of 9 samples of soil and 7 samples of cereals were measured in the Department of Radiation and Environmental Protection, Irnica Institute of Nuclear Sciences, using three high -purity germanium detectors for gamma spectrometry measurements. In all the samples, transfer factors for Ra-226 are significantly lower than for K-40, but they are all in good agreement with the literature data. On the three investigated locations, the calculated values of transfer factors for K-40 were in the range of 0.144 to 0.392, while in the case of Ra-226, the transfer factors ranged from 0.008 to 0.074. Only one value (0.051) was obtained for transfer factor of Th-232. Specific activities of Cs-137, as well as uranium isotopes, in all the investigated cereal samples, were below minimal detectable activity concentrations. Also, the absorbed dose rate and the annual absorbed dose from the natural radionuclides in the soil, were calculated. The absorbed dose rate ranged from 49-86 nSv/h, while the annual absorbed dose ranged from 0.061-0.105 mSv. The measurements presented in this manuscript are the first to be conducted in the region of Pcinja, thus providing the results that can be used as a baseline for future measurements and monitoring.