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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.

The prevalence of beryllium sensitization and chronic beryllium disease by job category was examined among individuals tested in the Rocky Flats Beryllium Health Surveillance Program. The program offered ongoing beryllium health surveillance for any current or former employee who believed they may have been exposed to beryllium at the Rocky Flats Environmental Technology Site. Of the 18,589 living individuals contacted, 7,573 requested participation and 6,614 (87.3%) eventually participated. Of this group, 78.2 percent were found to have verifiable job and building histories. The beryllium lymphocyte proliferation test was used to identify beryllium-sensitized individuals. Sensitization and chronic beryllium disease rates were analyzed with respect to gender, building work location(s), and length of employment at Rocky Flats. Several job categories and buildings were strongly associated with the 81 cases of chronic beryllium disease and the additional 154 cases of beryllium sensitization in this population. Beryllium sensitization was highest among beryllium machinists, 11.4 percent (odds ratio = 3.04, compared to the remainder of those tested, 95 % confidence interval = 1.48, 3.97) and health physics technicians, 11.9 percent (odds ratio = 2.87, 95% confidence interval = 1.12, 7.36). However, odds ratios were also increased among custodial employees, 5.64 percent (odds ratio = 1.30, 95% confidence interval = 0.92, 1.85) and other job titles that were thought to have only minimal potential for exposure to beryllium.

The first case of chronic beryllium disease (CBD) at the Rocky Flats Environmental Technology Site (Rocky Flats) was diagnosed in a machinist in 1984. Rocky Flats, located 16 miles northwest of Denver, Colorado, is part of the United States Department of Energy (DOE) nuclear weapons complex. Research and development operations using beryllium began at Rocky Flats in 1953, and beryllium production operations began in 1957. Exposures could have occurred during foundry operations, casting, shearing, rolling, cutting, welding, machining, sanding, polishing, assembly, and chemical analysis operations. The Beryllium Health Surveillance Program (BHSP) was established in June 1991 at Rocky Flats to provide health surveillance for beryllium exposed employees using the Lymphocyte Proliferation Test (LPT) to identify sensitized individuals. Of the 29 cases of CBD and 76 cases of beryllium sensitization identified since 1991, several cases appear to have had only minimal opportunistic exposures to beryllium, since they were employed in administrative functions rather than primary beryllium operations. In conjunction with other health surveillance programs, a questionnaire and interview are administered to obtain detailed work and health histories. These histories, along with other data, are utilized to estimate the extent of an individual's exposure. Additional surveillance is in progress to attempt to characterize the possible risks from intermittent or brief exposures to beryllium in the workplace.