244
-
1954
§&.H. COHN
=i.
c
RARE -EARTH GROUP _-17 pe
OPERATION
REDWING
cs 37
7°
1957
sr?” (9.0001)
RETURN TO RONGELAP
137.
111.
s
1959
1961
zn
|
se" (anos)
ae
[ane
A sr (6.0089)
b cof?
0.0
and,
0.1
L
02
has
03
iL
04
L
05
L
O5
=
07
0.8
pe
Fig.4
Estimated body burdens of isotopes in Rongelap people, 1954-1962
skeleton, gives an average value of approximately 2 pc/g calcium or 2 ne
for the body burden, This was approximately tenfold higher than the aver-
age (0.19 pe/g Ca) reported in January 1958 for adult bone in the world[12].
In March 1962 another check by direct measurement of a bone sample was
possible.
An autopsy samples of rib and vertebra of a 79-year-old
Marshallese woman gave Sr® values of 13.7 + 0.5 and 16.3 + 0.4 pe/g.
These bone vaiues are equivalent to a skeletal body burden of 9.1 - 13.7 nc
when normalized [11].
The average Sr%° excreted by the adult group in 1962 was 11.454 1.30
pe/l, or 114+ 14 pe Sr ™ /g Ca. The Sr9 body burden estimated from these
urine data was 12.0 nc, which compares favourably with the value obtained
from the bone samples above. The variation in urinary excretion values
of Sr®° is quite large in the population (Table IJ), This variation is probably a result of analytical errors, physiological fluctuations in urinary
excretion and the variation in the Sr® level in the individual diets. With
the small sample size and the wide spread in any group, it is not possible
to detect any significant difference in urinary Sr* /Ca between the group
of Marshallese exposed in 1954 and the unexposed control group. There
are also wide differences in Sr/Ca levels as a function of age and sex.
For example, in 1962 the Rongelap children (5-15 yr) had a mean Sr/Ca
ratio in urine more than twice that of the adult group. In a world-wide study,
children (5-15 yr) were found to have three times higher skeletal Sr °° /Ca
eat rt
ratio than adults [12]. The Sr9? [Ca ratio was found to be independent of