Radium - 226 levels in some sudanese plants and soils

摘要

The natural levels of (sup 226) Ra in plant and soil samples have been studied. The field study was mainly conducted in western Sudan (Darfur and Kurdofan) where areas of high natural background radiation have been identified and Khartoum area was taken as a control to (i) assess in natural setting the soil-to-plant concentration ratios (concentration in dry sample / concentration in dry soil) of the naturally occurring radionuclide (sup 226) Ra, (ii) establish base-line data on Radium activity concentration levels in environmental materials and (iii) explore the area of high natural radiation background in western Sudan.Low level gamma spectrometry, employing high purity germanium detector (HPGe) of relative efficiency 12%, has been used for the determination of (sup 226) Ra activity concentrations in plant and soil samples. The mean Radium activity concentration found in soil ranged from 14.41 Bq/Kg to 79.08 Bq/Kg, the values correspond to the reported normal background levels of (sup 226) Ra in soils worldwide. Radium activity concentrations found in Sudanese plants were significantly higher compared to those related to plants from normal background regions and significantly lower than those reported for plants from high background regions in other countries. The mean soil/plant concentration ratios (CRs) found in this study were 0.12, 0.15, 0.17 and 0.08 for whole plants, fruits and leafy vegetables, root vegetables and grains, respectively. These ranges of CR values are comparable with overall range of CR where environmental conditions are normal. The estimated daily intakes by individuals consuming foods of local origin were 1.00, 10.4 and 7.91 Bq/Day of radium Khour Abu Habil, Arkuri and Dumpir, respectively. Since the dietary habits were different, as it was noticed, these results have been much lower in comparison with those obtained from some European countries and United States. (author), 44 refs., 18 tabs., 13 figs. (Atomindex citation 28:045136)