Appendix 9 (continued) C. Data on Principle Isotopes of Iodine Contributing to Thyroid Dose (From "Inhalation of Radioiodine from Fallout: Hazards and Countermeasures" by R. Colel37) Enax? Mev Relative Range in abundance, Z% tissue, um 50%-Dose radius,* um | Iodine-13] Betas 0.246 0.332 2.2 10.6 0.807 0.8 0.606 1,000 86.4 2,100 | 150 310 Todine-132 Betas 0.681 0.934 15 20 2,500 3,900 375 625 1.583 2.111 22 21 8,400 11,900 1,500 2,400 6,800 1,200 8,100 45,800 1,460 3,300 1,300 195 1.150 22 5,400 920 Iodine-133 Betas 0.49 1.34 7 93 Iodine-134 Betas 0.87 1.55 2.65 3.51 5 65 25 5 Todine~-135 Betas 0.40 1.00 1.43 35 40 25 | 4,300 7,300 690 1,300 *The 50%-dose radius is defined, for a point source in tissue, as the distance within which 50% of the dose, for that energy, isa distributed. **Since this isotope with 53-min half-life is important only for about 6 hr, it was not considered in the Marshallese thyroid dose calculations. - 117 ~ °