Heavy metals such as zinc (Zn), cadmium (Cd) and lead (Pb) are frequently found in excessive concentrations in soils. The aim of this study was to assess the transfer of Zn, Cd and Pb by hemp grown in the Celje Basin in soils with elevated Zn, Cd and Pb concentrations. A block field experiment with seedlings was set up in the growing season of 2021, with 4 varieties of common hemp from the European Variety List (Carmagnola Selected, Elleta Campana, Finola and Tiborszallasi) and 4 doses of zeolite (0 kg, 0.1 kg, 0.5 kg and 1 kg) added to the planting hole prior to planting. At maturity of the female plants, the plants were harvested and the concentrations of Zn, Cd and Pb were measured in the roots, leaves and inflorescence, as well as in the inflorescence extract. The highest Zn concentrations were measured in leaves (55.6-254.6 mg/kg dry matter (DM)), followed by inflorescences (74.6 to 182.5 mg/kg DM) and finally roots (52.1 to 93.9 mg/kg DM). The highest concentrations of Cd were measured in the roots (0,7 to 1,4 mg/kg SS), followed by the inflorescence (0,2 to 0,5 mg/kg SS) and the lowest in the leaves (0,15 to 0,45 mg/kg SS). The highest concentrations of Pb were measured in the roots (3,4 to 6,2 mg/kg SS), followed by the leaves (0,49 to 1,99 mg/kg SS) and the lowest in the inflorescence (0,3 to 1 mg/kg SS). No statistically significant differences were observed in the effect of different zeolite doses on Zn, Cd and Pb concentrations, except for Pb concentrations in inflorescences, where the only significant difference was found between 0,1 kg and 1 kg zeolite dose. The inflorescence extract obtained by ethanol extraction does not exceed the recommended daily intakes for all three heavy metals studied, which means that hemp could be safely grown on this soil for the purpose of flower extract production.
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