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Title: Dose Reconstruction for the Million Worker Study: Status and Guidelines

The primary aim of the epidemiologic study of one million U.S. radiation workers and veterans (the Million-Worker study) is to provide scientifically valid information on the level of radiation risk when exposures are received gradually over time, and not acutely as was the case for Japanese atomic bomb survivors. The primary outcome of the epidemiological study is cancer mortality but other causes of death such as cardiovascular disease and cerebrovascular disease will be evaluated. The success of the study is tied to the validity of the dose reconstruction approaches to provide unbiased estimates of organ-specific radiation absorbed doses and their accompanying uncertainties. The dosimetry aspects for the Million-Worker study are challenging in that they address diverse exposure scenarios for diverse occupational groups being studied over a period of up to 70 years. The dosimetric issues differ among the varied exposed populations that are considered: atomic veterans, DOE workers exposed to both penetrating radiation and intakes of radionuclides, nuclear power plant workers, medical radiation workers, and industrial radiographers. While a major source of radiation exposure to the study population comes from external gamma-ray or x-ray sources, for certain of the study groups there is a meaningful component of radionuclide intakes thatmore » require internal radiation dosimetry measures. Scientific Committee 6-9 has been established by NCRP to produce a report on the comprehensive organ dose assessment (including uncertainty analysis) for the Million-Worker study. The Committee’s report will cover the specifics of practical dose reconstruction for the ongoing epidemiologic studies with uncertainty analysis discussions and will be a specific application of the guidance provided in NCRP Reports 158, 163, 164, and 171. The main role of the Committee is to provide guidelines to the various groups of dosimetrists involved in the various components of the Million-Worker study to make sure that certain dosimetry criteria are respected: calculation of annual absorbed doses in the organs of interest, separation of low-LET and high-LET components, evaluation of uncertainties, and quality assurance and quality control. Lastly, we recognize that the Million-Worker study and its approaches to dosimetry are a work in progress and that there will be flexibility and changes in direction as new information is obtained, both with regard to dosimetry and with regard to the epidemiologic features of the study components.« less
 [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7] ;  [6] ;  [8] ;  [9] ;  [9] ;  [10] ;  [3] ;  [11] ;  [12] ;  [13] ;  [14] ;  [15] ;  [16]
  1. National Cancer Inst., Rockville, MD (United States)
  2. M. H. Chew & Associates, Oak Ridge, TN (United States)
  3. National Council on Radiation Protection and Measurements, Bethesda, MD (United States)
  4. New York, NY (United States)
  5. Memorial Sloan Kettering Cancer Center, New York, NY (United States)
  6. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  7. Oak Ridge Associated Univ., Oak Ridge, TN (United States)
  8. International Epidemiology Inst., Rockville, MD (United States)
  9. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  10. Clarksburg, MD (United States)
  11. US Nuclear Regulatory Commission (NRC), Washington, DC (United States)
  12. Univ. of Southern California, Los Angeles, CA (United States)
  13. US Nuclear Regulatory Commission (NRC), Arlington, TX (United States)
  14. Risk Assessment Corporation, Neeses, SC (United States)
  15. Landauer, Inc., Glenwood, IL (United States)
  16. Southwest Research Institute, Boulder, CO (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0017-9078; HU2006300
Grant/Contract Number:
AC05-76RL01830; SC0008944; U01 CA137026
Accepted Manuscript
Journal Name:
Health Physics
Additional Journal Information:
Journal Volume: 108; Journal Issue: 2; Journal ID: ISSN 0017-9078
Health Physics Society
Research Org:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org:
USDOE; USEPA; National Aeronautics and Space Administration (NASA)
Country of Publication:
United States
59 BASIC BIOLOGICAL SCIENCES; 62 RADIOLOGY AND NUCLEAR MEDICINE; National Council on Radiation Protection and Measurements; dose reconstruction; occupational exposures; radiation workers; Million Worker Study
OSTI Identifier: