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NATIONAL INSTITUTES OF HEALTHCLINICALSTAFF
TABLE 2,

Estimated Body Burden of

- Rongelap People

Isotopes

Activity
at Day 1

Activity .
at Day 82

Sr
MwoBa
Rare earth group
WT (in thyroid gland)
8Ru
Ca
Fissile material

1.6-2.2
0.34-2.7
0-1.2
6.4-11.2
0-0.013
0-0.019
0-0.016 (ug)

uc

0.19 .
0.021
0.03
0.0
—
0.0
0.0

present at 82 days after exposure. The most

abundant isotopes were those of strontium
and iodine. However, the people excreted
this material quite rapidly.

When

they

moved back to their home island we were

able to detect an increase in body burdens

in both exposed and comparison popula-

tion due to the slight residual activity per-

sisting on the island. This activity was

largely due to 87Cs, Zn, and Sr. The

body burdens of these elements have been

ascertained from whole-body counting techniques and radiochemical urinalyses. During the first few years after the people of
Rongelap moved back the levels showed
slight increases in these elements but have
since leveled off, and it is believed the peo-

ple are in equilibrium now with these ele-

ments in their environment. The levels are

far below the accepted permissible levels.
Until the recent development of thyroid

nodules in the Marshallese people there
' were only a few late effects of radiation that

we could relate to radiation with any degree of certainty. A persisting lag in recovery of the white blood cells and platelets
until about II] years’ postexposure was be-

lieved perhaps to be a lingering effect of
radiation exposure on the bone marrow.
Figure 7 shows the percent difference in the
blood counts of the exposed Rongelap people as compared with those of the unexposed population.

The general health of the people remained about as good in the exposed peo-

gUd Lue

i

Annals of
Internal Medicine

ple as in the unexposed comparison population. Mortality has been slightly greater
in the exposed people, and we are notcertain if this is related to radiation or not;
but. there are a larger number of older

people in the exposed group, which may

partly account for this. Based on birthrates,
fertility appears to have been about the same
in the exposed and the unexposed people.
An increase was noted in miscarriages and
stillbirths during the first 4 years after exposure of the women. During this period
13 of 30 pregnancies in the exposed group
(41%) ended in stillbirths or miscarriages,
compared with only 8 of 49 (16%) tn the
unexposed women.
We have carried out studies to see if
radiation produced any enhancement of
aging by attempting to quantify such things
as measurement of skin elasticity, hair
graying, baldness, visual acuity, accommodation and arcus senilis of the eyes,
audiometric measurements, blood pressure,
strength, neuromuscular function, and body
potassium levels. Most of these criteria
showed good correlation with aging. By
combining values for these parameters we
were able to arrive at a biological age score
for each individual. We have not, however,
detected any significant difference in aging
in the exposed as compared with the unexposed population. Indeed, the subtle effects of aging would probably be most diffcult to assess, and perhaps the tests we are
using are not sensitive enough to detect

the effects of radiation at this dose level.
Degenerative diseases have been studied
and compared in the two groups, and we

have not seen any difference in prevalence.

There have been three cases of cancer: two
of the female genital tract in the exposed
women and one case of cancer of the thyroid, which I will discuss later. Since the
numberofcases is so small, we do not know
whether this represents any radiationinduced increase in malignancy or not. We

have noted only one case of cancer in the
unexposed group. There were no radiation-

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