Development of rapid methods for assessing doses from internally deposited radionuclides

During the initial phases of the National Institute for Occupational Safety and Health Radiation Dose Reconstruction Program, all calculations of organ doses due to internally deposited radionuclides were performed using the Integrated Modules for Bioassay Analysis program. However, limitations associated with this program, including the need to calculate separate internal dose assessments for each radionuclide, created inefficiencies in the processing of claims. As a result, the National Institute for Occupational Safety and Health developed and introduced a suite of tools to expedite the process. The first of these was the Chronic Annual Dose Workbook program. This innovative tool permits a dose reconstructor to calculate, in a single step, an organ dose that involves up to 255 separate intakes in any combination of radionuclides, intake modes, and absorption types. In addition, the program enables dose reconstructors to determine the specific radionuclide characteristics that will deliver the highest organ dose for a specific intake. Furthermore, the results are displayed in a format that is compatible with the Interactive RadioEpidemiological Program, which is used by the U.S. Department of Labor in establishing the probability of causation. The value of the probability of causation, in combination with other information, subsequently enables the U.S. Department of Labor to render a decision on compensability. These developments have played a major role in enabling the dose reconstruction teams to meet the claim processing goals with increased efficiency and accuracy.