Translocation of Plutonium from Rat and Monkey Lung after Inhalation of Industrial Plutonium Oxide and Mixed Uranium and Plutonium Oxide

Abstract

This study was designed to compare the translocation from lung of the Pu contained in the pure and mixed industrial oxides PuO2 and (U,Pu)O2. The latter had a Pu content of 20% w/w. For this purpose, young adult male rats and male and female baboons were exposed to a single inhalation of these oxides. Two baboons were exposed to the reference PuO2, i.e. 239PuO2. Rats were killed under anaesthesia 1, 15, 30, 90 and 180 days after exposure, and baboons, also under anaesthesia, 1 year thereafter. The results indicate that lung retention of Pu was independent of the oxide inhaled, but was smaller in rat (12-15% of the initial pulmonary burden, 6 months after exposure) than in baboon (56-80% of this burden, 1 year after exposure). In rat, Pu translocation kinetics were similar for the two industrial oxides, but as from day 15 after inhalation until 6 months thereafter, measurement of Pu deposits in the liver and skeleton showed that translocation of Pu from the mixed oxide was 2-3 times greater than that from the industrial Pu oxide. In baboon, the largest amounts of Pu were retained in the lung and thoracic lymph nodes for the three oxides inhaled. Pu translocation to the liver, skeleton and kidneys, and also urinary Pu excretion, were greater after inhalation of the mixed oxide than after inhalation of the industrial and reference Pu oxides. Nevertheless, the amount of mixed oxide Pu translocated to these sites and excreted in urine remained under 3% of the initial pulmonary burden.

Mieux connaître le devenir biologique des futurs matériaux nucléaires, une nécessité pour maintenir un bon niveau de radioprotection

“…Les résultats dépendent fortement de la technique utilisée pour la préparation de l'oxyde. Le plutonium ne se comporte pas différemment chez le singe qu'il soit inhalé sous forme d'oxyde pur préparé à 1000°C ou bien sous forme d'oxyde mixte, à 20 % de plutonium, préparé à 1680°C (Lataillade et al, 1995). Si l'oxyde mixte a été préparé à partir d'une solution solide la solubilité du plutonium, mesurée in vitro, est augmentée (Eidson et Mewhinney, 1983).…”

Application of voxel phantoms to study the influence of the heterogeneous distribution of actinides in lungs on in vivo counting using animal experiments

“…An 8 kg female baboon (Papio papio) was contaminated by acute intra-tracheal instillation of MOX aerosol using specific devices of the LRT (Lataillade et al, 1995). The initial activity deposited in the lung was 800 kBq of MOX aerosol of type MIMAS 4 (AMAD = 3.5 µm; specific activity = 12.3 GBq kg -1 ), which isotopic composition is presented in Table I.…”

“…Thus, the uncertainty due to the heterogeneity of contaminations can be better assessed and the effect of a realistic heterogeneous contamination on the measurement can be studied in a way that would be impossible by an experimental approach. Further studies will be performed to confirm the possible extrapolation of the conclusions to human measurement despite the morphological differences in the thoracic cage and the physiological differences that exist between humans and other primates after incorporation of a material in the same physico-chemical form (Lataillade et al, 1995).…”

Pulmonary retention of actinides after dissolution of PuO2aerosols: interest in modelling DTPA decorporation

“…Data are now available regarding the specific biological behaviour of each element. This compound was also studied few years after its fabrication ( 241 Am: ~15% of the total alpha activity) and biokinetic data have been reported after inhalation exposure (Lataillade et al, 1995). In addition, a second PuO 2 , generated by the same industrial process, was also studied for the first years following fabrication (Ramounet et al, 2000).…”