The measurement of intracellular zinc in human intestinal mucosa using x-ray microanalysis

The zinc content of intestinal epithelial cells in human jejunum and ileum has been measured using X-ray microanalysis. The range of values was wide, the highest being found in stem cells and enterocytes. Significant differences were found in jejunum from gastric carcinoma patients and ileum from Crohn's disease patients compared with patients with non malignant, non inflammatory disease.     

Trace metal levels in freshwater fish, sediment and water

The trace metal concentrations in water, sediment and aquatic organisms, such as fish, could indicate the level and tendency of the pollution. This is important not only for the protection of the environment, but for evaluation of the quality of fish meat either captured from natural waters or cultured in fishponds. The total trace metal concentrations in samples of fish from different regions of Hungary and from different species have been determined by using an X-ray fluorescence technique (EDXRF). Water, sediment and fish samples from fishpond systems with different feeding and stocking has also been analyzed. In the case of zinc contents, differences have been traced between the cultured and wild common carp. In the case of common carp reared under different feeding conditions, differences were also observed in the zinc concentration. The retention of the trace metals in the fish has been studied by measuring the levels in sediment, water and feed. The different retention can be explained by the different availability of zinc in the applied feeds, which can be related to the presence of different metal species in the feeds.     

A validation study for the transport of 134Cs to strawberry

The paper presents results on model validation by field experiment for transport of 134Cs to strawberry. The transfer of 134Cs to herbaceous plants was investigated following a wet deposition after an acute release during 2000. Leaf-to-fruit, soil-to-fruit and direct fruit pathways were examined. The available meteorological and local soil information together with the experimental data were taken into account by the model RUVFRU. The processes are described by first order differential equations. In the case of foliar contamination scenarios measured and calculated results for fruit are in good agreement. However, the results of soil contamination scenarios provide large differences of up to three orders of magnitude between model predictions and experimental values for either fruit or other parts of the plant. The bias could be explained by the underestimation of the interception of the plant at the beginning of the season, in the soil contamination scenario. The model output permits prompt assessment of emergency situations and provides aid making decisions concerning mitigation of the consequences of the accident.     

Evaluation of a model for leaf to fruit transfer of radionuclides in processing tomato plants using an independent set of data

Because of their varied possibilities of consumption, tomatoes are an important component of the human diet. This paper presents results of the evaluation of a dynamic model (Ventomod) for the short-term behaviour of radionuclides deposited on tomato plants following a direct contamination event. To check its forecasting capability in assessing the risk of radionuclide contamination of the human diet, it has been tested with an independent dataset on the leaf to fruit transfer of 134Cs in a typical Hungarian tomato variety, "Dwarf of Kecskemet". Data obtained from this pot experiment were used to evaluate model behaviour. Model constants were varied according to the differences between the Hungarian dataset and the one used to calibrate it. Results show that the model output well reproduces the observed activity of fruits for various levels of contamination and at different contamination dates. The main part of this report summarises the experimental protocol, compares the experimental results with model predictions generated by Ventomod and makes recommendations for both updating model parameters and undertaking further experimental work.