Final report of the group research. Studies on the comparative evaluation on the environmental toxicants released from advanced technology and industry. (Research Group of NIRS)

This report concerns investigations on the title conducted by 4 subgroups of National Institute of Radiological Sciences (NIRS) during the period of April 1996-March 2001. The report involves summary reports from the subgroups for Model for risk estimation of environmental and biological impacts of radiation and toxic agents, Analysis of the distribution and behavior of toxic and tracer elements in the environment, Studies on construction of controlled experimental ecosystems for ecotoxicity evaluation, and Metabolism and effect of environmental toxicants and new risk assessment. Significant results are as follows: Development of the model HESANS for health risk assessment (already published and used for actual practice through the internet) and of SIM-COSM in future for computer toxicity test; Development and improvement of the methods to measure more than 50 elements by means of high-technology analytical equipment; Introduction of Microcosm (an aquatic microbial ecosystem) for evaluation of the effects and risks of environmental toxicants in comparison with radiation (γ-ray); and Metabolic interaction of Gd (a neutron absorber in nuclear fuel processing) and Pu. The research groups thus have a number of important findings with respect to the kinetics and effects of radioactive substances and environmental toxicants. (N.I.)