@misc{oai:repo.qst.go.jp:00068113,
 author = {Ishii, Nobuyoshi and Tagami, Keiko and Uchida, Shigeo and 石井 伸昌 and 田上 恵子 and 内田 滋夫},
 month = {Mar},
 note = {Tecchnetium-99 (99Tc) is a fission product of 235U and 239Pu with a relatively high yield of about 6%. The half-life of this radionuclide is 2.1 * 10^5 years, implying its presence in the environment for many generations. The main sources of 99Tc in the environment are nuclear weapons testing and nuclear fuel reprocessing plants.
In aerobic conditions, Tc is present as pertechnetate (TcO4-), which is both highly soluble and mobile in the environment. It acts as a sulfate analog and assimilation of TcO4- by plants raises concern about the transfer of 99Tc to human though agricultural plants. We previously reported that Tc in agricultural soil surface water would transform from soluble TcO4- to insoluble form (> 0.2 um in size). It is difficult for the plant to take in the insoluble Tc in this size.
The formation of insoluble Tc in the soil surface waters seems to be caused by microorganisms. In this study we describe kinds of microbes contribute to the insoluble Tc., 30th　Annual Meeting},
 title = {Contribution of bacteria on the insoluble technetium formation in paddy soil surface water},
 year = {2004}
}