ABSTRACT
The results are presented from estimation of spatial distribution of 137Cs and 90Sr contamination densities in the areas of horses and sheep grazing within the Semipalatinsk Test Site. Dose burdens to various cohorts of the population living within the STS and consuming contaminated animal products are predicted. Doses of shepherds in the most contaminated pasture areas have been found to exceed the accepted limit (1 mSv/y). The conclusion is made about the need for further studies on the risk assessment of the STS population exposure above the accepted limits.
Subject(s)
Agriculture , Cesium Radioisotopes/analysis , Radioactive Pollutants/analysis , Strontium Radioisotopes/analysis , Animals , Food Contamination, Radioactive/prevention & control , Kazakhstan , Occupational Diseases/prevention & control , Radiation Injuries/prevention & control , Risk Assessment , Rural PopulationABSTRACT
Advisability of using risks as indicators for estimating radiation impacts on environmental objects and humans has been jusified. Results are presented from identification of dose burdens distribution to various cohorts of the population living within the Semipalatinsk Test Site (STS) and consuming contaminated farm products. Parameters of dose burden distributions are estimated for areas of livestock grazing and the most contaminated sectors within these areas. Dose distributions to meadow plants for the above areas have been found. Regulatory radiation risks for the STS population and meadow ecosystem components have been calculated. Based on the parameters estimated, levels of radiation exposure of the population and herbaceous plants have been compared.
Subject(s)
Ecosystem , Environmental Pollution , Radiation Dosage , Radiation Monitoring/methods , Risk Assessment/standards , Animal Husbandry , Animals , Dose-Response Relationship, Radiation , Food Contamination, Radioactive/prevention & control , Humans , Kazakhstan/epidemiology , Occupational Diseases/prevention & control , Radiation Injuries/prevention & control , Rural Population , Soil Pollutants, Radioactive/analysisABSTRACT
A mathematical model of 137Cs behaviour in the soil-plant system is presented. The model has been parameterized for the area adjacent to the testing area Ground Zero of the Semipalatinsk Test Site. The model describes the main processes responsible for the changes in 137Cs content in the soil solution and, thereby, dynamics of the radionuclide uptake by vegetation. The results are taken from predictive and retrospective calculations that reflect the dynamics of 137Cs distribution by species in soil after nuclear explosions. The importance of factors governing 137Cs accumulation in plants within the STS area is assessed. The analysis of sensitivity of the output model variable to changes in its parameters revealed that the key soil properties significantly influence the results of prediction of 137Cs content in plants.
Subject(s)
Environmental Monitoring , Models, Biological , Plants/chemistry , Soil Pollutants, Radioactive/analysis , Cesium Radioisotopes/analysis , Predictive Value of Tests , RussiaABSTRACT
The paper describes mathematical models for 137Cs behavior in the organism of horses and sheep pasturing on the bording area to the testing area "Ground Zero" of the Semipalatinsk Test Site. The models are parameterized on the base of the data from an experiment with the breeds of animals now commonly encountered within the Semipalatinsk Test Site. The predictive calculations with the models devised have shown that 137Cs concentrations in milk of horses and sheep pasturingon the testing area to "Ground Zero" can exceed the adopted standards during a long period of time.
