At the 27th “Environmental Radioactivity” Research Meeting, held in March 2026, 15 years after the TEPCO’s Fukushima Daiichi Nuclear Power Plant accident, we conducted a survey among attendees regarding their opinions for the several remaining research points related to environmental radioactivity. Following the survey result, because many attendees showed their intention on ALPS-treated water discharge and the effect to the environment, the topic was selected for the following free discussion. Through this discussion, we found that many scientists thought that the environmental impact of this discharge to be negligible, given the current situation We also found that there is a scientific need to clarify the transfer mechanisms of elements and/or materials in the environment, and their environmental impact, using radionuclides caused by the accident as a tracer.

In this study, we investigated a method for quantifying K⁺ concentration in infusion solutions using β-ray measurement derived from the naturally occurring radionuclide ⁴⁰K. K⁺ in 40 mL of infusion samples were adsorbing onto 3 g of medical cation exchange resin, and enabling the removal of coexisting components such as glucose from the infusion samples. K⁺ concentration in various infusion solutions was measured using radioluminography, and the method achieved quantitative accuracy within 95–105% of the nominal concentrations containing 40 or 60 mEq/L potassium. This method is expected to be applicable for preventing medical accidents caused by potassium-containing infusions.

Hospital-based cyclotron facilities require an integrated operational system after implementation of in-house fluorine-18 fluorodeoxyglucose production. This article summarizes practical issues encountered during the first two years of routine operation, including standard operating procedures and change control, equipment and environmental management, quality assurance, personnel training and backup capacity, inventory and radioactive waste management, radiation safety management, and coordination with clinical departments. Detailed analyses of individual topics, including occupational exposure, waste management, irradiation conditions, questionable quality test results, post-maintenance changes, and inventory management, are outside the scope of this article and are treated as separate topics. The experience indicates that sustainable operation depends on an integrated quality assurance system that links responsibilities, communication pathways, documentation, education, and continuous improvement. In addition to the conventional principles of time, distance, and shielding, two complementary operational radiation protection principles are proposed: avoiding production of unnecessary radioactivity beyond clinical demand and preventing concentration of occupational exposure and workload in particular workers. Radiation protection in hospital-based radiopharmacy therefore begins at the stages of production planning and workforce organization.