Distribution, retention and early cytogenetic damage in Cynomolgus monkeys following inhalation of 239Pu(NO3)4

Sixteen Cynomolgus monkeys were exposed by inhalation to an aerosol of 239Pu(NO3)4 which resulted in calculated initial lung burdens of 1.0, 0.3 and 0.1 μCi. Four animals were exposed to the carrier aerosol and served as controls. Animals were sacrificed at 4 days and 45 days after exposure to determine the distribution and retention of the aerosol. The amount of plutonium in the liver, skeleton and testes increased as a function of time after exposure. Two monkeys died 155 and 188 days after inhalation exposure from radiation pneumonitis and fibrosis. There was a doubling of the total chromosome aberration frequency in the blood lymphocytes and a significant increase in dicentric chromosomes in the animals exposed for 6 months to initial lung burdens of 1.0 μCi