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This paper presents the analysis of urine bioassay data, spanning four decades, from five workers who had wounds contaminated with plutonium at the Department of Energy Rocky Flats Plant during the period 1961-1967. The cases were selected from participants in the Department of Energy-sponsored Former Radiation Worker Medical Surveillance Program at Rocky Flats, which provided medical monitoring, modern bioassay measurements, and internal dose re-evaluations for former Rocky Flats workers. The cases include a variety of wound types, excision treatment regimes, and monitoring information. These wound cases illustrate the use of two multi-compartment wound models and three plutonium urine excretion models for retrospective calculation of internal plutonium depositions resulting from wounds for which no chelation therapy was administered. Wound model compartment fractions and half times are determined for each case and urine excretion model as are composite parameter values. The urine analysis and wound count measurements obtained under the program provide data with state-of-the art measurement sensitivity, as well as the opportunity to include long-term excretion and wound site data that exceed 10,000 d post-exposure for retrospective intake and dose evaluations. These data are provided to the radiation dosimetry community for use in developing and testing improved models for plutonium deposition in wounds.

The United States Department of Energy (DOE), Office of Occupational Medicine and Medical Surveillance, has supported an ongoing Former Radiation Worker Medical Surveillance Program at the DOE Rocky Flats site since 1992. The program currently is managed for DOE by Oak Ridge Institute for Science and Education through a contract with Oak Ridge Associated Universities. Participation in the program is entirely voluntary and provides former Rocky Flats workers who were exposed to radiation with long-term medical monitoring and an update to the assessment of their radiation dose. Program participants receive medical examinations and in vivo and in vitro bioassay measurements of residual radioactivity. Radiation doses to participants are largely a result of internal depositions of plutonium and its radioactive decay products. The causes of many of the higher internal doses were accidents that generally are well documented. Former radiation workers are invited to participate in the program if they meet specific criteria for radiation exposure. Informed consent is documented using a consent form approved by an Institutional Review Board. Demographic, medical, and dosimetric information is maintained in a computer database and will be evaluated for any trends or correlations between exposure and health outcome.