17 Sep 2015 Report on the KHNP-RHI International Seminar 2015

“Recent Advancement on Radiation Emergency Medical Preparedness & Dose Evaluation”

The KHNP-RHI International Seminar 2015 took place on September 17, 2015, hosted by Radiation Health Institute (RHI) of Korea Hydro & Nuclear Power Co. Ltd. (KHNP). The theme of this seminar was to share experiences from the Fukushima Daiichi Nuclear Power Plant accident. KHNP, which has four nuclear power plants with 23 operating reactors in South Korea, is the sole nuclear power company in the country. The main topics covered in the seminar were emergency medical response and effects of radiation exposure on recovery workers following the accident. A delegation from Japan included Koichi Tanigawa, MD, PhD, Vice President, Fukushima Medical University, and Makoto Akashi, MD, PhD, Executive Director, National Institute of Radiological Sciences (NIRS).

Dr. Tanigawa first presented the history of Japan’s radiation emergency medical system prior to the Fukushima nuclear accident. He described that since 1999, when a criticality accident occurred at the JCO uranium-conversion plant in Tokai-Mura, the system had mainly focused on response efforts for work-related injuries associated with a massive dose of radiation exposure, and had not anticipated multiple disasters compounded by a large-scale natural disaster. He also reported the following: in the event of the Fukushima accident, many lives were lost in evacuation from hospitals or nursing homes; medical facilities surrounding the nuclear power plant were rendered inoperable due to evacuation orders and fear of radiation; and general medical needs were not related directly to health effects of radiation but rather, were primary care issues: trauma, common illnesses, and psychiatric and affective disorders. Furthermore, he reported that the greatest challenge the accident posed was public health and mental health support for many residents coping with prolonged displacements from home.

Dr. Akashi introduced the initial medical response to the Fukushima nuclear accident, and radiological protection of emergency workers. Immediately after the nuclear disaster, NIRS dispatched a Radiation Emergency Medical Assistance Team (REMAT) to the Off-Site Center five kilometers away from the power plant. However, he noted that infrastructure including phone lines was damaged by the earthquake, and the team was required to provide medical care to evacuees and workers, making it difficult for the center to function as a command facility. Moreover, finding medical facilities that accepted workers injured in the hydrogen explosion on March 14 was even harder. Regarding radiological health effects among emergency workers on site, he mentioned the followings: six workers with doses over 250 mSv and one with over 160 mSv have not developed health effects, including thyroid disease, from radiation exposure; out of 2000 workers who were given stable iodine tablets for prophylaxis, 75% took less than 10 tablets in total, whereas some took 87 tablets; although follow up after that found the occurrence of temporary hypothyroidism in three of them, there were no serious side effects other than that.