Ishigure N, Nakano T, Enomoto H, Fukuda S, Iida H, Oghiso Y, Sato H, Takahashi S, Yamada Y, Koizumi A
Division of Radiotoxicology, National Institute of Radiological Sciences, Chiba, Japan.
J Radiat Res. 1994 Mar;35(1):16-25. doi: 10.1269/jrr.35.16.
A lung retention function on the amount of PuO2 in rats was determined. Five rats were exposed to polydisperse aerosols of PuO2 having a size of 0.47 micron activity median aerodynamic diameter. The initial lung burden was between 1990 Bq and 2960 Bq. Instead of serial-sacrifice study, in vivo counting of low energy L X-rays with thin NaI(Tl) scintillation detectors was used to follow the lung retention of Pu at various intervals up to 468 days after inhalation. The calibration of this counting system was made by measuring lung activity of rats sacrificed for other experimental purposes. It was confirmed that the potential skin contamination and the Pu translocated to the other organs was not counted at the present counting geometry. Our results showed that 77% of PuO2 deposited deep in the lung was cleared with a half-time of 53 days, whereas the residual 23% stayed there for a longer period (a half-time of 795 days).
测定了大鼠肺部对二氧化钚含量的潴留功能。五只大鼠暴露于粒径为0.47微米（活度中值空气动力学直径）的多分散二氧化钚气溶胶中。初始肺部沉积量在1990贝克勒尔至2960贝克勒尔之间。采用薄碘化钠（铊）闪烁探测器对低能L X射线进行体内计数，以取代连续牺牲研究，从而在吸入后长达468天的不同时间间隔跟踪肺部对钚的潴留情况。该计数系统的校准是通过测量因其他实验目的而处死的大鼠的肺部活度来进行的。证实了在当前的计数几何条件下，潜在的皮肤污染和转移到其他器官的钚未被计数。我们的结果表明，沉积在肺部深处的77%的二氧化钚以53天的半衰期被清除，而剩余的23%则在肺部停留更长时间（半衰期为795天）。
