1979 年 14 巻 4 号 p. 225-230
Tissue distribution of intravenously injected polymeric plutonium in mice was studied by liquid scintillation counting. The purpose of this study was to know the effect of plutonium administered at different dose levels on its distribution to the tissues. The fraction of deposition and average dose rate to the highly radiosensitive tissues such as the bone marrow and testes were also of our concern.
The polymeric plutonium prepared in this institute was demonstrated to have colloidal properties by showing high deposition in the liver and spleen for a long time. Percent uptakes of plutonium in the main tissues except in the kidneys were not influenced by the three different doses from 5μCi/kg to 15μCi/kg body weight of 239Pu. At 28 days after injection, femoral bone, femoral marrow and testes contained 1.23, 0.18 and 0.063 percent of the injected doses, respectively. At 56 days, the uptakes of the plutonium in the same three tissues were 1.23, 0.17 and 0.057 percent respectively. Average dose rates to the liver, lungs, kidneys, testes and femoral bone were proportional to the amount of plutonium administered. On the other hand, average dose rates to the spleen and bone marrow were characteristic in that they were not proportional to the amount of plutonium administered. Elevated dose rates (rad/day) were obtained in the spleen and the bone marrow, where there were weight losses resulting from the internal exposure to the deposited plutonium. Therefore, radiation dose to the spleen and bone marrow can not be solely obtained in proportion to the administered dose.
