The Sea Journal of the Korean Society of Oceanography ISSN:1226-2978(Print) 2671-8820(Online) 한국해양학회지 바다

Marine radionuclide research in Korean seas has been continuously conducted in response to various events starting with the disposal of radioactive waste in the East Sea by the former Soviet Union (now Russia) followed by the fallout from nuclear weapon testing, releases from nuclear power plants, and the Fukushima Daiichi nuclear accident in 2011 together with the discharge of treated radioactive wastewater in 2023. Since the Fukushima accident, extensive studies have been carried out in coastal waters for the direct and indirect inputs of radionuclides into the ocean including their transport pathways in the surrounding seas of Korea and their spatial and temporal distributions. These efforts have also brought increasing attention to the potential impacts on marine environments and biological systems. In addition, more than 300 nuclear power plants are currently planned and/or under construction in the seas surrounding the Korean peninsula including South Korea, Japan, and China, which raises public concern over nuclear safety in the northwestern Pacific region. Also, the Japanese government has released treated wastewater from the Fukushima Daiichi Nuclear Power Plant into the ocean on several occasions and plans to continue these discharges over the next 30 years. These actions have drawn significant domestic and international attention and concern regarding their potential impacts on the marine environment. Recently, the scope of radionuclide research has expanded to investigate the long-term behavior, bioaccumulation, and biogeochemical cycling of radionuclides in seawater, marine sediments, and both benthic and marine organisms. Such studies provide essential scientific backgrounds for (1) protecting public health, (2) ensuring the stability of marine ecosystems, and (3) managing the radioactive safety of coastal seafood. Marine radioactivity has emerged as a significantly important issue that extends beyond environmental concerns to one requiring international cooperation and transparent data sharing. Thus, it is crucial to establish a real-time monitoring and science-based early warning systems. This paper provides a comprehensive overview of recent developments in marine radionuclide research conducted in Korean coastal waters following the Fukushima accident. This study also highlights recent trend and emphasizes the urgent need to establish a rapid detection and monitoring framework to support sustainable and responsive marine radiological surveillance in the future.