Repeated Inhalation Exposure of Beagle Dogs to 239PuO2

Abstract

Whole-body retention and distribution of 239Pu in selected tissues of Beagle dogs were determined after a series of two or four inhalation exposures to 239PuO2. Exposures were made at half-year intervals with alveolar depositions of about 150 nCi per exposure. Data are reported on dogs followed for one and two years after the first exposure. The plutonium was found to be extremely insoluble; 2-3% of the amount deposited in the alveolar region translocated to tracheobronchial lymph nodes and less than 0.1% translocated to other tissues. The whole-body retention, when compared to retention of 239Pu following a single exposure, supported the hypothesis that each exposure was retained independently with the same retention characteristics. This is in agreement with results reported by other investigators for one human repeatedly exposed by inhalation to low levels of aerosols containing plutonium-uranium fuels.

Lung, Liver and Bone Cancer Mortality After Plutonium Exposure in Beagle Dogs and Nuclear Workers

“…In dogs, multiple exposures to alpha-particle emitters increase the cumulative organ dose-rate, which results in the increase of the cumulative dose, although at a lower magnitude than expected from other radiation (Diel and Lundgren 1982). The dogs used in these analyses were given a single exposure, while the MPA worker cohort probably experienced ongoing, chronic exposures, particularly during the early years of MPA operation.…”