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. Colet37)
E
max’
MeV
Relative
abundance, %
Range in
tissue, um
50%~Dose
radius,* un
Iodine-131 Betas
0.246
2.2
0.332
10.6
0.606
0.807
1,000
86.4
0.8
150
2,100
310
375
Iodine-132 Betas
0.681
15
2,500
0.934
20
3,900
1.150
1.583
2.111
22
22
21
625
5,400
8,400
11,900
920
1,500
2,400
6,800
1,200
8,100
15,800
1,460
3,300
Teodine-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
35
40
1,300
4,300
195
690
1.43
25
7,300
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, 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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