@article{oai:repo.qst.go.jp:00044139,
 author = {Muramatsu, Yasuyuki and Noda, Yutaka and Yonehara, Hidenori and Ishigure, Nobuhito and Yoshida, Satoshi and Yukawa, Masae and Tagami, Keiko and Ban-nai, Tadaaki and Uchida, Shigeo and Hirama, Toshiyasu and Akashi, Makoto and Nakamura, Yuuji and 村松 康行 and 野田 豐 and 米原 英典 and 石榑 信人 and 吉田 聡 and 湯川 雅枝 and 田上 恵子 and 坂内 忠明 and 内田 滋夫 and 平間 敏靖 and 明石 真言 and 中村 裕二},
 journal = {Journal of Radiation Research},
 month = {},
 note = {In the Tokai-mura criticality accident, three workers were heavily exposed. Biological materials, such as blood, urine, vomit and hair, were collected from the workers and analyzed for radioactivities, produced by the neutron irradiation. Activation products, such as 24Na, 42K and 82Br, were found in these materials by gamma-ray spectrometry. The radionuclide of the highest activity observed in biological materials was 24Na, e.g. the concentrations of this nuclide in the blood samples from the three patients at the accident time were 169, 92 and 23 Bq/ml, respectively. The concentrations of stable sodium in the same samples were determined by ICP-AES to obtain specific activities of 24Na (concentration ratio between the produced 24Na and stable 23Na), which are essential for estimating the neutron fluences and radiation doses. The specific activities of 24Na obtained for the three patients through the blood analysis were 8.2 x104, 4.3 x104 and 1.2 x104 Bq24Na/g23Na. Based on these values, individual's neutron fluences were estimated to be 5.7 x1011, 3.0 x 1011 and 0.85 x 1011 cm-2, respectively.},
 pages = {117--128},
 title = {Determination of radiation produced by neutrons in heavily exposed workers of the JCO criticality acccident in Tokai-mura for estimating an individual's neutron fluence.},
 volume = {42},
 year = {2001}
}