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- Author or Editor: A. Hamwi x
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Abstract
A relatively simple method has been developed for the determination of210Pb via its 
-emitting daughter,210Bi. Lead-210 was separated from interfering elements as lead sulphate. The precipitate was dissolved in an alkaline solution of EDTA and the Cerenkov signal produced by the build-up of210Bi was counted 30 days after storage using tritium channel of a liquid scintillation counter. Cerenkov counting efficiency was found to be approximately 20%. A lower limit of detection of 5.1 mBq/1 (based on 3
of the background with 500 minute counting time) was achieved. Chemical recoveries in the range of 70–100% were determined gravimetrically. Interference associated with currently used methods is avoided. Data from from both spiked samples and natural samples are presented.
Abstract
The experiment aimed to evaluate the vertical migration of 134Cs, 90Sr and 238Pu in the main types of Syrian soils; entisol, inceptisol, alluvial (rock outcrops) and gypsiferous soils, using soil columns through which the aqueous solution of the radionuclides percolated. The results show that the vertical migration of the studied radionuclides through the soil profile depend on the radionuclide and the soil type. More than 97% of 134Cs and 238Pu concentrated in the upper 2 cm of the entisol, inceptisol, and alluvial soils, whereas only 46.2% to 68.6% of the 90Sr was retained in the upper 2 cm of these soils. The vertical migration of the studied radionuclides in the gypsiferous soil was different from the other soils. The distribution of the radionuclides in the gypsiferous soil was irregular through the soil profile and reached the deeper layer of the soil. This may be due to its physical characteristics; poor structure stability, high permeability and low retention capacity.
Abstract
More than one hundred different food stuffs (meat, vegetables cereals, seafood,..) have been collected during 1998, 1999 and 2000 and analyzed for radioactivity as part of the National Food Monitoring Program in Syria. Results have shown that most of the observed concentrations were within the range of the worldwide values with the exception of relatively high levels of 210Po being observed in fish, vegetables, mushrooms, herbs and flowers. The daily intakes of the radionuclides studied have been evaluated. Relatively high values, in comparison with some countries, were found for 210Po (1.9 Bq/day). This is due to high content of 210Po in wheat (2.3 Bq/kg) consumed by Syrians, the daily consumption of wheat by Syrians is about 526 g. In addition, natural and artificial radionuclides in some manufactured food of Syrian infant and their intake rates have been determined. Seventeen manufactured food and eleven types of canned milk were collected from the local market and their radioactivity analyzed. 210Po activity concentration varied between 0.38 and 2.89 Bq/kg dry wt. in canned milk while the highest concentration in infant food was found to be 1.69 Bq/kg dry wt. Other radionuclide concentrations were below the limit of detection of 3 Bq/kg dry wt. and 4 Bq/kg dry wt. for 226Ra and 228Ra, respectively, while uranium concentration varied between 2.2 and 10.5 µg/kg dry wt. in milk samples and 0.78-6.0 µg/kg dry wt. in other food samples.
