An objective of a safety assessment for geological disposal is to evaluate the radiological impact by radionuclides release from radioactive wastes. Computational estimation of all radionuclides transport in the disposal system, however, is not neccessary because some radionuclides has negligible effect on radiological doses. For this reason, prioritization of radionuclides list is preceded before the safety assessment. The Korea Atomic Energy Research Institue (KAERI) has assessed the long-term safety of a disposal system for spent nculear fuels. Currently, thirty eight radionuclides and twenty three elements are considered in the safety assessment activity of the KAERI. Nevertheless, a screening process for radionulides selection has not been articulated yet. In this study, we reviewed radionuclides selection process in forign countries to re-establish screening criteria for the KAERI’s radionuclides list. Screeing models of the Swedish Nuclear Fuel and Waste Management Company (SKB), the Deparment of Eenrgy (US DOE), and the Japan Nuclear Cycle Development Istitute (JNC) were compared. We found that each country developed different screening model depending on scenarios of radionuclides release. Nonetheless, there were common properties that determines the importance of radionuclides. These properties for radionuclides include halflife, radiotoxicity (or specific activity), and mobility in underground medium. Based on the review results, we proposed radionuclides selection process to prioritize the importance of radionucldies in the KAERI safety assessment.

According to previous reports, antioxidant activities of Codonopsis lanceolata could be increased by a steaming process. This study was performed to improve its antioxidant activity and skin whitening activities of C. lanceolata by high pressure and stepwise steaming complex process. The complex processed C. lanceolata showed highest free radical scavenging acitivity as 45.21%, and for phenol and flavonoid contents, complex processed C. lanceolata contained higher than those from conventional extraction process or steaming process alone. The Cytotoxicity of all C. lanceolata extracts also showed low cytotoxicity against human fibroblast cell (CCD-986sk) as 4.49 ~ 10.40%. In whitening activity, high inhibition of tyrosinase activity was estimated as 25.08% by adding the extracts from complex process. We found that whitening and antioxidant activity of complex processed C. lancolata extract was higher than those obtained from conventional extraction and a steaming process because various kinds of antioxidant compounds could be easily released by combined process, compared to one of each process.