Radium-226 uptake by vegetation grown in Western Sudan

A study of the uptake of 226Ra by cultivated crop plants was carried out in uncontaminated regions of purely natural radioactivity. Activity concentration of 226Ra in soil and plant samples was measured. In farm soils analysed, the total activity concentration ranged from 14.4–79.1 Bq/kg and the exchangeable fraction constituted 7.1–27.8% of the total radium content. In the plants analysed, activity concentration levels found ranged from 0.7–23 Bq/kg and 0.1–7.6 Bq/kg dry weight for vegetative and edible crop parts, respectively. Soil/plant CRs related to exchangeable radium showed ranges of 0.09–3.31 and 0.01–0.34 for vegetative and edible crop parts, respectively. Soil pH, organic matter content (OM%), clay content, exchangeable cations (potassium, calcium and magnesium) and available phosphorus were determined with the aim to investigate their influence on radium uptake. Our results also show the existence of a tendency for a lower transfer of radium to edible parts than to the vegetative parts.