Ingestion dose evaluation reflecting Korean environments

Abstract

In the case that radioactive materials are released to the off-site environment due to the nuclear plant accident, the area in the vicinity of the site and the food from them will be contaminated for relatively long time. Thus, It is important for level 3 probabilistic safety assessment (L3 PSA) to evaluate the ingestion exposure from the intake of contaminated food with the consideration of the agricultural and dairy characteristics and conditions in the interested area, especially in the intermediate and long-term phase. COMIDA2 is a preprocessor for the ingestion dose evaluation using the semi-dynamic food chain model of MELCOR accident consequence code system (MACCS) which is one of the L3 PSA computational code widely used in the US, Korea, and the other countries. In this study, input variables of COMIDA2 such as food category, consumption rate for each category, time parameters and etc. were modified, reflecting Korean environmental characteristics from the valid statistic data. Instead of other livestock category, pork, the foodstuff whose consumption of Korean is relatively large, was included in the food category. Then, the individual effective ingestion dose for the several accident date cases was evaluated according to the food category. This analysis was conducted on the single radionuclide, Cs-137 because it is a key contributor to the long-term food contamination and ingestion exposure. It is figured out that the time relation between the accident date and the sowing data of agriculture products would have a great impact on the results. The results of this study would be expected to enhance the reliability and the completeness of L3 PSA in Korea.