Assessment of tritium distribution and radiation exposure pathways for the general public around the Hanbit nuclear power plants KIM HEEGANG Advisor : Prof. Tae young Gong, Ph.D. Department of Nuclear Engineering, Graduate School of Chosun University ...
Assessment of tritium distribution and radiation exposure pathways for the general public around the Hanbit nuclear power plants KIM HEEGANG Advisor : Prof. Tae young Gong, Ph.D. Department of Nuclear Engineering, Graduate School of Chosun University This study thoroughly evaluated the environmental distribution of tritium and the internal radiation exposure of the general public living near the Hanbit nuclear power plants. It recognized that tritium, released during normal plant operation, can continuously affect both the environment and human health due to its physicochemical similarity to water. Between 2017 and 2021, air samples, drinking water samples, and urine samples were collected from local residents and analyzed using liquid scintillation counting. Additionally, meteorological parameters such as atmospheric stability, wind speed, and wind direction were integrated to quantitatively characterize the dispersion and environmental transfer of tritium. The results indicated that tritium concentrations tended to increase under specific atmospheric stability conditions, dominant wind directions (ESE–SSE), and low wind speed. A significant positive correlation was observed between tritium concentrations in the air and drinking water (r = 0.70, p ≈ 0.05). Consistent trends were also found in urine samples, suggesting that the measured human uptake reflected the environmental distribution characteristics. Based on the maximum tritium concentration measured in urine samples (3.92±0.60 Bq/L), the estimated annual internal effective dose was 7.73×10-5 mSv/y, which corresponds to only 0.00773% of the public dose limit recommended by the International Commission on Radiological Protection and the World Health Organization. Even a conservative assessment using maximum environmental concentrations yielded a total effective dose of 9.53×10-4 mSv/y (0.0953%). These findings show that tritium exposure for residents living near the Hanbit nuclear power plants is radiologically negligible. They also indicate that an integrated, measurement-based approach linking environmental monitoring with human biomonitoring provides a strong scientific basis for improving radiation impact assessment, environmental surveillance, and radiation protection strategies in areas surrounding nuclear power plants.