Development of a radioiodine decontamination procedure

The McMaster Nuclear Reactor is one of the world's leading producers of iodine-125(t½ = 59.4 d, E_γ = 35 keV), filling more than 60% of the global demand for this therapeutic isotope. Due to the widespread presence of this isotope in our facility, identifying an effective means of removing radioiodine contamination from skin is an important priority from a radiation safety standpoint. Unfortunately, iodine forms covalent bonds to the amino acid residues in skin, making it difficult to remove. The goal of this study was to determine the most efficient method of I-125 removal from skin. Using pig skin as a surrogate due to the similarity of the epidermis, skin swatches were exposed to both liquid and volatile forms of I-125 for predetermined exposure times; a variety of mechanical and chemical exfoliants and wiping methods were then used to remove the I-125. The results of these experiments will be presented. (author)