Research Abstract


Isotopic evidence of plutonium release into the environment from the Fukushima DNPP accident

2012年3月8日 Scientific Reports 2 : 304 doi: 10.1038/srep00304


鄭 建1, 田上 恵子1, 渡辺 嘉人1, 内田 滋夫1, 青野 辰雄1, 石井 伸昌1, 吉田 聡1, 久保田 善久1, 府馬 正一1 & 伊原 禎雄2

  1. 独立行政法人 放射線医学総合研究所
  2. 奥羽大学 生物学
The Fukushima Daiichi nuclear power plant (DNPP) accident caused massive releases of radioactivity into the environment. The released highly volatile fission products, such as 129mTe, 131I, 134Cs, 136Cs and 137Cs were found to be widely distributed in Fukushima and its adjacent prefectures in eastern Japan. However, the release of non-volatile actinides, in particular, Pu isotopes remains uncertain almost one year after the accident. Here we report the isotopic evidence for the release of Pu into the atmosphere and deposition on the ground in northwest and south of the Fukushima DNPP in the 20–30 km zones. The high activity ratio of 241Pu/239+240Pu (> 100) from the Fukushima DNPP accident highlights the need for long-term 241Pu dose assessment, and the ingrowth of 241Am. The results are important for the estimation of reactor damage and have significant implication in the strategy of decontamination.