Tritium determination in natural water samples in Fukushima from 2022 to 2023 using an ultra-low-level tritium counting system.

This article focuses on measuring and assessing tritium concentrations in environmental water samples near the Fukushima Daiichi Nuclear Power Plant (FDNPP) following the 2011 accident. Using an improved Solid Polymer Electrolyte (SPE) enrichment method, researchers analyzed rainwater, river water, and coastal brackish water collected from Tomioka Town, south of the FDNPP, finding tritium levels generally low and comparable to historical and regional background values. The measured concentrations, all below the Japanese government's detection limit of 0.1 Bq/L for water, correspond to annual effective radiation doses from drinking water intake that are minimal and considered safe. The study emphasizes the importance of continued monitoring to ensure public safety and supports the reliability of the improved SPE method for low-level tritium detection in environmental waters.