The Biokinetics of Plutonium-239 and Americium-241 in the Rat After Subcutaneous Deposition of Contaminated Particles from the Former Nuclear Weapons Site at Maralinga: Implications for Human Exposure:

As an input to dose assessments, measurements have been made of the clearance of Pu and Am after subcutaneous implantation in rats for six particulate materials and one dust from the Maralinga test sites. The tissue distribution of Pu and Am were measured in groups of six animals at one month and 6 months after implantation. In addition, in vitro solubility tests were carried out on eight different particulate materials. Histological examination of the subcutaneous implantation site was undertaken after one year for selected materials. Autoradiographs of tissue sections showed that particles were surrounded by fibrotic tissue with macrophage and polymorphonuclear cell infiltration, the normal tissue response to foreign materials. The clearance data have been used to make estimates of the likely range in potential radiation doses in humans. To calculate the dose from dissolved 239Pu and 241Am, four different situations have been considered. For the dust, the results suggest that dissolution essentially cea...