Study on Dose Assessment of Chronic Atmospheric Releases of Tritium

An improved dose assessment model for chronic atmospheric releases of tritium is proposed. The proposed model explicitly considers three chemical forms of tritium as well as the parameters in accordance with diet customary in China. It is based on conservative assumption of transfer of HT (tritiated gas) and HTO (tritiated water) from air to concentration of HTO and OBT (organically bound tritium) and HTO from air to concentration of HTO and OBT in vegetable and animal products. The dose to human is calculated from an assumed diet, drinking water, inhalation and skin absorption. This model considers the animal weight for calculating the concentration of tritium in animal product. The ingestion dose is calculated based on considering dividedly leafy plan and not leafy plant for plant products. For animal products, we considered the contribution of HTO and OBT from diets to the concentration of HTO and OBT of animal products, at the same time we also account for the animal weight. We wish that the study could provide theoretical basis for improvement about dose assessment code of tritium in radiation protection and environmental assessment in nuclear environment in China.