USE OF COMBINED ALPHA-SPECTROMETRY AND FISSION-TRACK ANALYSIS FOR THEDETERMINATION OF PU-240 PU-239 RATIOS IN HUMAN TISSUE/

Plutonium and other actinides were determined in human autopsy tissues of occupationally exposed workers who were registrants of the United States Transuranium and Uranium Registries (USTUR). In this study, Pu was purified and isolated from Am, U and Th, after drying and wet-ashi ng of the tissues, and the addition of Pu-238 as a radiotracer. After electrodeposition onto vanadium planchets, the Pu239+240 activity was determined by alpha-spectrometry. A fission track method was developed to determine Pu-239 in the presence of Pu-238 and Pu-240, using Lexan (TM) polycarbonate detectors. Combining the two techniques allowed the determination of the Pu-240/Pu-239 activity and atom ratios. Data fro m selected USTUR cases are presented.