RESUMO
Permissible levels of radionuclides in soil were estimated for different human dose criteria. A variety of land-use scenarios, which could lead to human exposure, was considered and all reasonably likely human exposure pathways were analyzed. The obtained estimates are potentially useful for supporting the decision-making process on the possible use or remediation of contaminated territories.
Assuntos
Radiação de Fundo , Exposição Ambiental/análise , Fidelidade a Diretrizes/organização & administração , Monitoramento de Radiação/normas , Proteção Radiológica/normas , Resíduos Radioativos/análise , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Carga Corporal (Radioterapia) , Previsões , Regulamentação Governamental , Guias como Assunto , Internacionalidade , Monitoramento de Radiação/legislação & jurisprudência , Proteção Radiológica/legislação & jurisprudência , Resíduos Radioativos/prevenção & controle , Padrões de Referência , Medição de Risco/legislação & jurisprudência , Medição de Risco/normas , Medição de Risco/tendências , Federação Russa , Gestão da Segurança/legislação & jurisprudência , Gestão da Segurança/normas , Gestão da Segurança/tendênciasRESUMO
A mathematical model which simulates the observed dose-effect relationships for fish eggs exposed to chronic irradiation is presented. The model assumes that the exposed fish eggs may exist in one of the following states: normally developing, reversibly damaged, and lethally damaged. Reversible damages may be recovered by repairing mechanisms which are spent for the repairing processes. The model was applied to describe the observed differences in effects of chronic exposure for quickly (2 weeks) and slowly (up to 20 weeks) developing fish eggs. Calculations were performed for dose rates of chronic irradiation ranging from 10 to 300 mGy/day. Two types of radiation effects were considered-the effect on eggs survival (percentage of survived eggs at time t), and the depletion of the repairing pool (in percentage of its maximal value). The model predictions have been compared with the experimental data from the EPIC database. This comparison showed that the model adequately describes the radiation effects in fish eggs of different species, within a wide range of chronic radiation exposures.