[en] In recent years preparations for mining the uranium ore at Ranstad, in the Billingen region of the country of Skaraborg were carried out. The effects of ore dust released to the environment by the mining operations have been discussed. One problem was the impact of dust deposition on the transfer of natural radionuclides along the food chains. An investigation has been carried out on the content of uranium, thorium and radium in the soils and in the crops from 50 different sites. The farm sites were selected both within the Billingen region as well as neighbouring agricultural districts. The study comprises soils rather different with regard to characteristics such as the contents of clay and organic matter, pH and others. Also the activities of the radionuclides in the soil material varied considerably among the different soil types. By regression analysis relationships between the activities of the soils and their contents of clay and organic matter were established. Differences in the mobility of uranium, thorium and radium in soil due to the varying colloid contents were studied by the Ra/U-ratios. Concentration ratios between the nuclide contents of the crops and the soils as well as transport coefficients were established. The concentration ratios for the thorium nuclides were not directly dependent on the soil and plant characteristics available. Those for the uranium nuclides, however, were found to depend both on the plant nutrient uptake and on the pH-level in the soil. The Ra/Ca-ratio in plant was found to be mainly dependent on the ratio between exchangeable Ra and Ca in the upper soil layers. The increase in the nuclide transport due to the mining and processing activities was small and less than that due to normal fertilization with phosphorus during the same time. Also, the nat- ural variation in the transfer of the nuclides from soil to plant depending on differences between neighbouring soil types and on crops is of a much higher size of order than the impact of ore dust on plants and soil. (authors)