Acute and chronic intakes of fallout radionuclides @ S. L. SIMoNn ET AL.
189
Table 21. (Continued)
Birth year
and year
of tests
1948
1948
1951
1951
1952
1952
1954
1954
1956
1956
1958
1958
Utrik community
RBM
0.00020
0.00058
0.0053
0.019
0.016
0.019
1.7
10
0.0083
0.019
0.016
0.045
Rongelap Island community
Thyroid
Stomach
Colon
RBM
Thyroid
Stomach
Colon
0.046
0.14
1.1
3.9
3.4
4.0
460
2,600
1.1
2.7
3.3
8.9
0.00042
0.0012
0.0093
0.034
0.030
0.036
5.6
33
0.0085
0.020
0.029
0.078
0.0026
0.0026
0.055
0.20
0.17
0.20
0.033
0.10
0.010
0.035
0.016
0.020
16
97
0.017
0.036
0.036
0.087
11
33
2.2
8.1
4.0
AT
5,100
32,000
2.5
5.4
7.2
17
0.12
0.35
0.020
0.075
0.036
0.043
150
920
0.020
0.044
0.067
0.16
0.59
1.8
0.11
0.41
0.19
0.23
480
2,900
0.13
0.29
0.38
0.93
0.058
0.14
0.19
0.52
The uncertainty in the second term, O/Dep, depends
on the validity of the assumption that the ratio of the
acute intake and of the deposition density of '°'I at Utrik
for a TOI of 31 his the sameasthe ratio that would have
been obtained at Rongelap for the same TOI value.
Because there are no measurements of '°'l from which
the intake of the membersof the Utrik community can be
readily derived, the uncertainty in the best estimate for
Q/Dep at Utrik is greater than that at Rongelap. Thefact
source of internal contamination. The contribution from
inhalation is assumed minor, as, based on the meteorolog-
ical modeling described in a companion paper (Morozet al.
2010), the particle sizes of fallout from Bravo at Rongelap
and at Utrik were very large (20 pm). Because the
atmospheric conditions, the physical and chemical characteristics of the fallout, and the lifestyle and dietary habits of
the populations were similar at Utrik and at Rongelap, the
GSDfor Q('"'I, Bravo)/Dep(‘"'l, Bravo) at Utrik was taken
that, in the case of chronic intakes, the ratios of intake to
to be 2.0, which is not much greater than the value of 1.6
the two atolls (see Table 4) suggests that there are
uncertainties of an unknown nature that should be accounted for. It is worth keeping in mindthat the pathwaysleading to acute intake have not been quantitatively
described in an adequate way andthat it is assumedthat
be characterized by a GSD of 1.4, whichis slightly greater
than the value of 1.2 at Rongelap; this is due to the fact that
deposition of '’Cs differ by a factor of about 3 between
ingestion of fallout deposited on the skin, as well as on
cooking utensils and foodstuffs, was the predominant
that was determined for the GSD of Q('"'l, Bravo/C(‘"'1,
Bravo) for Rongelap. The same value was used for ‘I,
whichis strongly correlated with '°'l. Finally, the uncertain-
ties in the dosesper unitintake, D/O, at Utrik were taken to
there were no measurements of I in urine among the
members of the Utrik community.
Table 22. Sensitivity of organ doses (mGy) to assumptions in time-of-arrival (TOA). Estimated doses are for adults
exposed to Bravo fallout at four atolls and at three TOAs: (i) best estimate (BE) of TOA (Becket al. 2010), (11) best
estimate of TOA minus 20%, and (iii) best estimate of TOA plus 20%.
Organ dose, mGy
(% difference from dose based on best estimate TOA)
Atoll population
Majuro residents
Majuro residents
Majuro residents
Kwajalein residents
Kwajalein residents
Kwajalein residents
Utrik community
Utrik community
Utrik community
Rongelap Island community
Rongelap Island community
Rongelap Island community
TOA (h)
38
48
58
32
40
48
17.6
22
26
4.8
6.0
7.2
(BE —20%)
(BE)
(BE +20%)
(BE —20%)
(BE)
(BE +20%)
(BE —20%)
(BE)
(BE +20%)
(BE —20%)
(BE)
(BE +20%)
RBM
0.12 (11.8)
0.11 (0.0)
0.10 (—9.4)
0.27 (10.0)
0.25 (0)
0.23 (—7.5)
2.5 (9.7)
2.3 (0)
2.1 (-7.1)
27 (9.7)
25 (0)
23(-7.0)
Thyroid
26
22
20
77
66
58
880
740
630
8,100
7,600
7,100
(17.9)
(0)
(-12.1)
(17.5)
(0)
(— 12.6)
(18.9)
(0)
(— 13.9)
(6.9)
(0)
(—5.9)
Stomach
0.40
0.32
0.27
1.4
1.1
0.92
21
16
14
660
530
440
(23.6)
(0)
(- 16.6)
(25.2)
(0)
(— 16.0)
(27.2)
(0)
(- 16.1)
(23.8)
(0)
(— 17.0)
Colon
5.2
4.4
3.7
14
12
11
200
180
160
3,100
2,800
2,500
(18.7)
(0)
(- 14.4)
(14.5)
(0)
(—10.8)
(12.6)
(0)
(—9.1)
(10.7)
(0)
(—8.5)