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内容記述 |
Tritium (3H) is a radioactive isotope of hydrogen with a half-life of 12.32 y, originating from both cosmic-ray-induced nuclear reactions in the atmosphere and human nuclear activities. In the future, the nuclear fuel reprocessing plant in Aomori and the decommissioning of FDNPP represent two of the largest potential sources of planned and controlled tritium releases in Japan. Generally, urinary and drinking water analyses are employed to monitor the activity concentration and the effective dose of tritium for potential occupational and public exposures. Therefore, rapid and robust analytical methods for the measurement of tritiated water (HTO) and organically bound tritium (OBT) in urine and water are essential for the rapid response and screening in case of a large-scale radiological or nuclear accident. As the “core advanced radiation emergency medical support center” designated by Nuclear Regulation Authority, Japan, National Institutes for Quantum Science and Technology (QST), bears the responsibility of continuously enhancing the response capability for radiation emergency medicine in Japan. Therefore, QST has been engaged in international intercomparisons for the tritium analysis in urine and water, organized by the French organization PROCORAD (Association for the PROmotion of Quality Control in RADiotoxicological Analysis) since 2023. For radiation emergency preparedness, we developed rapid and robust tritium screening in urine and water by liquid scintillation counter, and improved lab manuals and lab specifications, during intercomparisons. Based on the performance criteria including Z-score, bias, and En value, our lab qualified as TOP LABOs in 2024 ARADOS (Asian Radiation Dosimetry Group) intercomparison and 2025 PROCORAD intercomparison. |
