Developing historical food production and consumption data for 131I dose estimates: the Hanford experience

This paper describes the methods used to reconstruct the movement of commercial foods in and through the study area of the Hanford Environmental Dose Reconstruction Project. The most dose-relevant radionuclide released from Hanford separations plants was 131I via the atmospheric pathway. As a result of atmospheric deposition of 131I, commercial food supplies may have been contaminated. Because the half-life of 131I is relatively short, foods consumed soon after production, such as milk and produce, presented the highest risk. For that reason, this paper deals primarily with the reconstruction of milk and produce production, marketing, and consumption from 1945-1951, the period with the highest known 131I releases. The reconstructed food production and consumption information was used as input to radiation dose estimates for representative individuals and as default values for real individuals who may not remember where they obtained food or how much they consumed during that period. Specific methods for tracing the movement of commercial milk and produce back from the point of human consumption, through commercial markets, to original production are presented. Results include the characteristics of food consumption exhibited by representative individuals, examples of commercial milk and produce market structures, and a review of commercial milk production and processing practices from 1945-1951.