TAM-A - Special Session: USTUR: Five Decade Follow-up of Plutonium and Uranium Workers
100 C 08:30 - 10:00
|Chair(s): Patricia R. Worthington|
08:30 KEYNOTE: The USTUR: Where we have been and where we are going RL Kathren*, Washington State University at Tri-cities
Abstract: The evolution of the USTUR is sketched from its modest beginnings as the National Plutonium Registry in 1968 through administrative and scientifically noteworthy significant events and findings over its history, beginning with its start of operations and development of operating protocols until the present day. Administrative events discussed include formation of the parallel U.S. Uranium Registry (1978) and its ultimate amalgamation (1989) with its elder sister registry to create the USTUR; the appointment and evolving role of the Scientific Advisory Committee; the changing role of the Registries and its relationships with other programs over the years; directors; adverse publicity and investigations into USTUR operations by the General Accounting Office and the special Presidential Advisory Committee on Human Radiation Experiments. Scientific events specifically discussed are the first program description and operating protocol publications in the peer reviewed literature (1972); the results of tissue analyses from the first 30 autopsies (1975); and the radiochemical analysis of first whole body donation which led to indicated changes in the generally accepted ICRP biokinetic model and improved calibration of in vivo counting for americium. Brief mention will be made of the postmortem findings in the Hanford accidental exposure case as well as other postmortem tissue evaluations along with the implications and indications of these findings with respect to modeling and protection standards. Postmortem radiochemical analysis of tissues obtained at autopsy and from whole body contributions have led to improved understanding of the biokinetics and improved values of biokinetic constants for uranium, plutonium, and americium. Such data lead to refinement of biokinetic models underlying internal emitter safety standards and include previously unrecognized differences in soft tissue and skeletal uptake and retention of plutonium and americium; in the residence time in skeleton for uranium; distribution and bone and liver cancer and leukemia risk coefficients; and the development of a refined biokinetic model for inhaled UF6. Finally, specific current ongoing research activities of the USTUR, both intra and extramural, and potential future directions are discussed.
09:00 KEYNOTE: The Atomic Man: Case Study of the Largest Recorded 241Am Deposition in a Human EH Carbaugh*, Dade Moeller
Abstract: The 1976 explosion of an ion exchange column at the Hanford Site resulted in the largest human uptake of 241Am ever recorded. The worker underwent wound debridement, extensive personal skin decontamination and long-term DTPA chelation therapy for decorporation of 241Am. Because of the contamination levels and prolonged decontamination efforts, care was provided for the first three months at a unique emergency decontamination facility with gradual transition to the patient’s home occurring over another two months. Follow-up monitoring and medical care was provided for the rest of his life. Upon his death 11 years later, from causes unrelated to the accident, the USTUR received tissue donations allowing detailed biokinetic and dose evaluation. Dubbed “the Atomic Man” by the press, USTUR Case 246 has been the subject of numerous reports and journal articles describing the accident, case management, dosimetry, and post-mortem findings. His systemic total body 241Am content was estimated to be 545 kBq at the time of death, distributed approximately 86% in the bone (primarily bone surfaces), 5% in the liver, 5% in other soft tissues, and 4% in the bone marrow. The distribution reflected the high degree of effectiveness of DTPA therapy in removing 241Am from soft tissue, and its relative ineffectiveness in removing it from bone.
09:30 Award Ceremony: Patricia R. Worthington on behalf of DOE Secretary promulgates recognition awards to Robert W. Bistline and Roger O. McClellan for their five decades contribution to the USTUR.