Reconstruction of thyroid doses for the population of Belarus following the Chernobyl accident

As a sequela to the large release of {sup 131}I from the accident at the Chernobyl Nuclear Power Plant, an expected late effect is thyroid cancer, especially in children. In anticipation of this problem, hundreds of thousands of measurements of thyroid glands were made with survey meters. Much attention was also focused on measuring the deposition density of {sup 137}Cs. The expectation was that the latter measurement could be a good surrogate for the deposition density of {sup 131}I, so that ecological models could be used to reconstruct thyroid doses in locations where no direct measurements of thyroid activity were made. However, this assumption has been seriously questioned, and there is interest in a more suitable surrogate that can still be measured even nine years or more after the accident. The purpose of this paper is to discuss the reconstruction of thyroid doses for a case-control study of childhood-thyroid cancer that has just been concluded, to discuss the reconstruction of thyroid doses for a current cohort study of childhood-thyroid cancer, and to discuss the use of {sup 129}I as a surrogate for the deposition density of {sup 131}I