Table 4.
Estimated thyroid risk due to radiation for exposed Marshallese 27
years after exposure.
(Corrected for incidence in age-matched
unexposed populations. )*
Nodules
Age
Av.
Hypothyroid
group
No.
dose
Total**
Risk
Ca
Rongela
<l0***
>10
Total
19
45
64
1000
387
569
14.6
2.5
17.1
28.5
5.3
17.4
0.8
2.6
3.4
Ailingnae
<10***
6
>10
12
Total
18
379
140
233
1.8
3.1
4.9
29.3
68.3
43.3
58
100
158
84
35
53
3.5
4.2
7.7
26.6
44.4
34.1
0.5
1.2
1.7
3.8
12.7
7.5
83
157
240
314
144
203
19.9
9.8
29.7
28.3
16.1
22.6
1.3
3.8
5.1
1.8
6.2
3.9
Utirik
<10%%*
>10
Total
All
<10
>10
Total
Risk
1.6
5.5
3.5
No.
All
Risk
No.
Risk
3
3.8
6.8
5
8.1
6.9
17.6
6.3
23.9
34.3
13.4
24.3
1.0
1.0
22.0
8.8
1.8
4.1
5.9
29.3
90.4
52.1
3.5
4.2
7.7
26.6
44.4
34.1
22.9
14.6
37.5
32.5
23.9
28.6
3.0
4.8
7.8
4.3
7.9
5-9
*Since it is possible that the thyroid doses used may be too low, on the
basis of reevaluation analyses now in progress, the above risk estimates may
be too high.
If the actual years at risk were used, i.e., years until
development of abnormality or death, the total number of years would be
reduced and the risk factors would be higher. The cancer risk is probably
underestimated since a number of people with nodules were not operated upon.
The ri sk for benign nodules was not included since a large number of
unoperated cases were likely to have been benign.
**Includ es also unoperated cases.
***Does not include the groups exposed in utero because of dose uncertainty.
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