Longer Lung Retention of PuO2 Particles Observed in Rats Measured Using Periodic In Vivo Counting

Abstract

The object of this study is to establish a lung clearance curve for PuO 2 in rats, which provides basic information on lung dosimetry. Rats were exposed to polydisperse aerosols of PuO 2 having a size of 0.47 μm activity median aerodynamic diameter. The initial lung burden (ILB) was between 1990 Bq and 2960 Bq. In vivo counting of low energy L X rays with thin NaI(Tl) scintillation detectors was applied to follow the lung retention of Pu. Our results showed that 77% of PuO 2 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 794 days)