Radioactivity in Soils and Vegetables from Uranium Mining Regions

Samples of soils, irrigation water, and vegetable products from three areas were analyzed for radionuclides. These areas are located in the basins of Ribeira da Pantanha, Ribeira do Castelo and streams tributaries to Ribeira de Inguias, all receiving drainage from old uranium mines. Results showed enhancement of radionuclide concentrations, especially 226Ra, in vegetables from kitchen gardensin these areas when compared with reference areas upstream the mine‘s discharge points.The main source and transfer pathway of radionuclides to plants was the irrigation water used, rather than the soil. Non-contaminated products were obtained in these areas when irrigation was made with non-contaminated water from deep wells, instead of water from surface streams and irrigation wells contaminated with mine drainage. Guidelines for radionuclide concentrations in irrigation water and soil are needed.