Models of Radioiodine Transport to Populations Within the Continental U.S.

A methodology is being developed to estimate the exposure of Americans to 131I originating from atmospheric nuclear weapons tests carried out at the Nevada Test Site (NTS) during the 1950s and early 1960s. Since very few direct environmental measurements of 131I were made at that time, the assessment must rely on estimates of 131I deposition based on meteorological modeling and on measurements of total ß activity from the radioactive fallout deposited on gummed-film collectors that were located across the country. The most important source of human exposure from fallout 131I was due to the ingestion of cows’ milk The overall methodology used to assess the 131I concentration in milk and the 131I intake by people on a county basis for the most significant atmospheric tests is presented and discussed. Certain aspects of the methodology are discussed in a more detailed manner in companion papers also presented in this issue. This work is carried out within the framework of a task group established by the National Cancer Institute.