EXCLUSIVE: 53,000 Fukushima N-Plant Workers Receive High Radiation

Tokyo, Aug. 23 (Jiji Press)–Over 53,000 workers at Tokyo Electric Power Company Holdings Inc.’s meltdown-stricken Fukushima No. 1 power plant have received radiation doses exceeding a key level of 5 millisieverts per year, Jiji Press has learned. The level of 5 millisieverts is a threshold for determining whether nuclear plant workers suffering from leukemia are eligible for compensation benefits for work-related injuries and illnesses under public insurance. The figure, which covered the 15 years to the end of March this year, is based on Jiji Press analysis of data in TEPCO’s annual reports on radiation management submitted to the Nuclear Regulation Authority after the March 2011 triple meltdown at the plant in Fukushima Prefecture. Meanwhile, a total of 17 cases of diseases such as solid cancer and leukemia had been recognized as work-related as of the end of March on grounds that there was a causal relationship between the diseases and radiation exposure during work to deal with the nuclear accident, according to the health ministry. With the work to decommission the Fukushima plant set to continue until the completion expected for 2041 to 2051, the number of work-related diseases resulting from high radiation exposure may increase further. Based on data from TEPCO’s reports, the cumulative number of workers exposed to more than 5 millisieverts per year had reached 53,145 as of the end of March this year. Of them, 403 workers exceeded 50 millisieverts per year in fiscal 2010, 205 in fiscal 2011, one in fiscal 2012 and none in fiscal 2013 or later. Before the accident, the upper limit of radiation exposure for nuclear plant workers and others handling radioactive materials was set at 100 millisieverts over five years and 50 millisieverts for one year under normal conditions. The average radiation dose per person was 21.6 millisieverts in fiscal 2010, 4.3 millisieverts in fiscal 2015, 2.6 millisieverts in fiscal 2020 and 1.7 millisieverts in fiscal 2025, showing a steady decline. Of the 17 cases recognized as work-related, eight were leukemia, while two each were throat cancer, thyroid cancer, lung cancer and colon cancer. A threshold for such recognition for solid cancer is a cumulative exposure dose of 100 millisieverts or more. According to the health ministry, at least two of the 17 cases resulted in the deaths of people who had worked at the plant. Data from fiscal 2025 reports on radiation management submitted by TEPCO and other power companies show that workers at the Fukushima No. 1 plant were exposed to radiation far more than their counterparts at nuclear plants of other companies. The total doses received by plant workers for the year reached 20.97 sieverts at the Fukushima No. 1 plant, far higher than the second-highest figure of 2.22 sieverts, recorded at Kansai Electric Power Co.’s Takahama plant, where all four reactors were operated. The third-highest total was 0.99 at Kyushu Electric Power Co.’s Sendai plant, followed by 0.80 at its Genkai plant and 0.75 at Japan Atomic Power Co.’s Tokai No. 2 plant. In terms of the number of workers with exposure doses exceeding 5 millisieverts in the year, the Takahama plant had 66, the Sendai plant 18, and the Tokai No. 2 plant 11, far lower than over 1,500 at the Fukushima No. 1 plant. END [Copyright The Jiji Press, Ltd.]