Appendix 9 (continued)
C.
Data on Principle Isotopes of Iodine Contributing to Thyroid Dose
_
E
max’
Mev
(From "Inhalation of Radioiodine from Fallout:
Hazards and Countermeasures" by R. Cole37)
Relative
abundance, %
Range in
tissue, um
50%-~Dose
radius,* um
Iodine-131 Betas
0.246
0.332
0.606
0.807
2.2
10.6
86.4
0.8
1,000
2,100
150
310
2,500
3,900
5,400
8,400
11,900
375
625
920
1,500
2,400
6,800
1,200
8,100
15,800
1,460
3,300
1,300
4,300
7,300
195
690
1,300
Iodine-132 Betas
0.681
0.934
1.150
1.583
2.111
15
20
22
22
21
Iodine-133 Betas
0.49
1.34
7
93
Iodine-134 Betas
0.87
1.55
2.65
3.51
5
65
25
5
Iodine-135 Betas
0.40
1.00
1.43
35
40
25
*The SO0%-dose radius is defined, for a point source in tissue, as the distance
within which 50% of the dose, for that energy, is 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.
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