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 ~
°