aa
52
Table 33
Urinary Sr®° Levels, in yuC/1, of Marshallese, 1959
Males
Age 1-15
Rongelap exposed
Rongelap unexposed
Ailingnae
Utirik
Ebeye
2.4
(2)*
7.12.0 (3)
-
Females
Age >15
Age 1-15
Age >15
5.1 (8)
+2.8 (9)
(1)
+0.9 (5)
0.56+0.37 (4)
3.9 (2)
3.9 (ft)
-
3.4 #2.2 (9)
4.2 #23 (6)
3.9
(1)
2.5
(2)
0.70+0.70 (3)
ated
*The numbersin parentheses are the numbers of people in the groups.
Table 34
Cs'37 Body Burdens, in muC/kg, of Marshallese as Measured by Whole-Body GammaSpectroscopy, 1959
Males
Age 1-15
Rongelap exposed
Rongelap unexposed
Ailingnae
Utirik
1246.2 (9}*
11.844.8 (20)
8.9
(2}
4.61.2 (14)
Females
Age >15
Age 1-15
Age >15
4.25.1 (10)
14.0+4.7 (37)
I1.5+3.6 (4)
4.51.6 (15)
11.34:2.7 (12)
9.92.1 (15)
10.0+3.1 (4)
4,541.9 (14}
11.0%3.4 (16)
9.82.8 (33)
11.4445 (5)
3.641.3 (15)
*The numbers in parentheses are the numbers of people in the groups.
Table 33). No significant difference was found
between the Rongelap exposed and unexposed
groups, although the exposed adult group had a
slightly higher mean value than the unexposed
group. Females tended to have a lower mean Sr*°
value than males, but the difference was notsta-
tistically significant. Relatively few children <15
years of age were tested for urinary Sr°’; therefore,
it was not possible to comparetheir levels statistically with those of the adults. The mean Sr*°
urinary value for an adult inhabitantof Utirik was
1.8 puC/1, which is about 35% that of the Ronge-
lap group. Thecontrol group on EbeyeIsland (not
contaminated) hadstill lower values, 0.62 puC/1.
The lack of significant difference between the
exposed and unexposed groups on Rongelap seems
to indicate that essentially no residual Sr*° from
the initial exposure is detectable in the exposed
group.
Cesium-137. The Cs'* urinary excretion levels
of the Marshallese people for the period from 50
to 180 days following exposure can be expressed
as a single exponential function with a half-life of
70 days (see Figure 56). This figure is not in agree-
ment with the value of 140 days obtained by Anderson,”* but a biological half-time of 51 to 59
days was obtained in a clinical study made over a
4-month period following injection of Cs'*’Cl,
into two patients.**
The estimates of body burden of Cs‘*’ in 1958,
derived indirectly from urinalysis, are presented in
Table 32.
The urinary excretion of Cs'*’ of 34 upC/I in
1957 indicates that the Rongelap people were ex-
posed to a continuing low level of Cs'*’ from
stratospheric fallout during 1956 while residing on
Majuro. By contrast, the mean body burden of
Cs'*7 in 1957 of the Utirik people (who were re-
turned to their atoll in 1954) was 334 mpC, considerably higher than that of the Rongelap people
who wereresiding on Majuroat that time.*° This
higher burden among the Utirik people in 1957
can beattributed to the higher level of Cs**" con-
tamination on Utirik than on Majuroat that time.
Zine-65. Zn®urinary levels were not measured
before 1958, With the assumptionsthat excretion
of Zn*° is exponential and urinary excretionIs
10% of total excretion (urinary/fecal ratio=‘),
the March 1958 urinary excretion level of 175
reesa
on an average 24-hr urine output of 1660 mi(see
Lc