Intrahepatic Distribution of Plutonium in Beagles

Abstract

GEARHART, J. M., DIEL, J. H., AND MCCLELLAN, R. O. Intrahepatic Distribution of Plutonium in Beagles. Radiat. Res. 84, 343-352 (1980). Autoradiographs of liver tissue sections were used to study the microscopic distribution of plutonium both by degree of uniformity and by association with morphological structures and cell types. The distribution of plutonium deposited in liver as a result of gradual introduction into blood by absorption from lung was compared with the distribution of Pu after acute intravenous injection of a soluble form of Pu. Beagle dogs were exposed by inhalation to a 238PuO2 aerosol or by intravenous injection to 238pu or 239Pu-citrate and the distribution of Pu in liver was measured (t = 64-1553 days) after exposure. Random distribution of plutonium at early times after exposure was changed to clustering of activity at times beyond 2 years after inhalation exposure. Plutonium which initially was distributed an equal distance from central veins and portal triads moved closer to central veins. The distribution of Pu in liver at the cellular level from high levels of Pu exposure was not the same as that at lower levels of exposure such as those most likely to be encountered by man. Particles were found in liver sections of animals that died by 1350 days after exposure by inhalation to a mean initial lung burden of 0.97 tLCi/kg body wt. This indicated that for high initial lung burdens, particle transfer can occur. At low levels of exposure, distributions of plutonium deposited in liver after translocation from lung and after intravenous injection were similar for at least 4 months after exposure.