Measurement of transfer factor – TF of radioactive elements in the fast-growing plant culture Helianthus tuberosus L (sunchoke)

<title>Abstract</title> <p> Research of usage of biomass for energy purposes is an important topic for the sustainable development and application of renewable energy sources in areas with developed agricultural production. As the basis for using renewable energy sources in technology, it is planned to grow fast-growing crops that have a high biomass yield per hectare. The use of renewable energy sources can be achieved by obtaining a large amount of organic matter for the production of biogas, which is then used in the cogeneration process [1] for the production of heat and electricity. A fast-growing crop, the plant Helianthus tuberosus L. - sunchoke, is an example of a crop that can be used for high biomass yield, as it grows with a yield of 130 to about 150 tons per hectare per year [2]. Thus, obtaining a significant amount of biomass where the carbon in the biomass structure is completely created from CO ₂ from the atmosphere. Sunchoke accumulates significant amounts of nutrients, including radionuclides from the soil. After biogas production, biomass is separated into liquid fertilizer and solid residue, in which radionuclides remain. Since both products return to the soil and potentially re-enter the food chain, it is necessary to evaluate the factors of radionuclide transfer from the soil to individual parts of this cultivated industrial plant. The research included sampling on two plots in Vojvodina. Several sunchoke plants were sampled in the post-flowering period, along with the soil in which the crop was grown. After sampling, the plants were separated into tubers, stems, leaves and flowers, and the radionuclide content was measured using an ORTEC HPGe GMX detector system [3] with the basic setting in the Laboratory of the Department of Nuclear Physics. The measured activity concentrations of detected radionuclides were in the following ranges: Cs-137, 2.84–12.5Bq/kg in soil and 0.6–1.67Bq/kg in tubers; Ra-226, 21.7–37.3Bq/kg in soil and 4.8–17.9Bq/kg in stems; and K-40, 399–553Bq/kg in soil and 705–1330 Bq/kg in flowers and leaves Based on the ratio of measured activity concentrations, radionuclide transfer factors for all samples were calculated according to the IAEA TRS-472 methodology [4]. The most important result of this research is that the plant reconcentrates potassium (K-40) in all its parts, which can affect the safety of food production and the exposure of the population through nutrition </p>