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Cesium-137 in forest fruits
VRBOVÁ, Anežka
Significant artificial radionuclides occurring in the environment include Cs-137 from nuclear weapons tests that took place in the atmosphere during the 1950s and 1960s, and nuclear power plant accidents, such as at Chernobyl block 4 and crash at Fukushima. This bachelor thesis compares the amounts of Cs-137 and K-40 in different types of forest fruits, such as blueberries, raspberries and blackberries. Certain sites in Šumava were selected for their collection, where there was significant radioactive fallout after the Chernobyl nuclear power plant accident in 1986. Using semiconductor gamma-ray spectrometers, the specific activity of Cs-137 and K-40 was measured. All samples were measured in the dry state (dry matter). Cs-137 measurement values ranged from 1,143 Bq.kg-1 to 500 Bq.kg-1. For K-40 measurements, the values ranged from 166 Bq.kg-1 to 1280 Bq.kg-1. Differing values in individual localities are the result of uneven rainfall when the radioactive cloud passed over our territory after the Chernobyl disaster. However, there are also differences between species of forest fruits, which exhibit different accumulation properties due to different root system depths and their surrounding soil properties. The measured values were compared to the established limits and radiation sources found in our environment. The values measured are not high and compared to other sources of radiation are negligible, which has little impact on our health.
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Comparison of radiological and chemical weapons in the context of their use in terrorist attacks against civilians
GUBRICKÝ, Václav
The thesis is focused on radiological and chemical weapons in the context of their use in terrorist attacks against the civilian population in relation to rescue and clean up operations of the Integrated Rescue System (IRS) of the Czech Republic. The objective of the thesis is to specify the terms of radiological and chemical weapons, to assess potential negative consequences of their use with the emphasis on the threat to life and health of the population, to evaluate the economic impact on society and to compare the IRS activities during the immediate intervention carried out after a terrorist attack. The topic is dealt with based on the research and the analysis of rules of law in force regulating activities of the IRS components in these major incidents and also of documents of the IAEA (International Atomic Energy Agency) and other works focused on the misuse of radioactive and chemical agents in terrorist attacks. Severity and complexity of the issue is illustrated by information given on the radiological accident in Goiana in Brazil, sarin attacks of the Japanese sect Óm šinrikjó and consequences of the model example of the use of radionuclide 137Cs. In the thesis the current methodology on which the IRS components operate in such emergencies is analyzed, and some aspects that are subject of the set of type activities, worked out by the Civil Emergency Planning Committee and DG Fire Rescue Service of the CR, which may become weak points during a real action of the IRS, are pointed out. One of major issues analyzed in this study is comparison of radiological and chemical attacks with the focus on the initial phase of the intervention of the IRS components. Presentation of differences in individual activities of the IRS components in such interventions can contribute significantly to understanding and subsequently managing the activities carried out by the IRS components in these major incidents.
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