45
mother was diagnosed as having congenital heart
disease and died several monthsafter birth. The
suggestive evidence of increased miscarriages and
stillbirths in the exposed women duringthefirst
few years after exposure mightbe related toirradiation of the germ plasm. Thefinding that male
children of exposed parents were shorter in stature
than children of the same age of unexposed par-
Thelevels of internal contamination per unit
weight appearedto be aboutthe samefor juveniles
such a conclusion.
Hematological studies showed that certain
time for comparison. The Zn®level in adult males
(1.51 muC/kg) dropped to 17% of the mean value
measured 2 years ago. With a larger detector and
a longer counting time than previously employed,
it was possible to identify and quantify Co” for the
first time in these people; the meanlevel of Co"
was about 11% of the Zn" level. A smal! amount
ents may have some genetic significance, but further studies would be necessaryto substantiate
peripheral blood elements in the more heavily ex-
posed Rongelap group continued to showslightly
lower levels than in the unexposed comparison
population, suggesting a persistent irradiationeffect on hemopoietic function. Examination of the
data by age and sex groups showedthat neutrophil and platelet levels among the exposed were
consistently below the unexposed levels, and that
exposed males aged 7 to 15 vears and exposed
persons, both males and females, aged >40 showed
the most difference from their controls. The ex-
posed males and females of ages 15 to 40 showed
less difference. with even higherlevels of someele-
ments than the unexposed groups of the same
ages. The plateiet levels. however. were consistently
lower in all age groups in both sexes. It was noted
also that male children of exposed parents had
somewhat lower levels of neutrophils, |lympho-
cytes. and platelets than children of unexposed
parents.
The Rongelap population as a whole continued
to showslightly lower erythropoietic function than
found generally in Americans, the explanation for
which is not clear. Thoughiron deficiency does
not appearto be a problem in view of generally
normal serum iron levels, some other type of
nutritional deficiency may be responsible. The
high incidence of eosinophilia may be partly
related to chronic fungus infection of the skin and
intestinal parasitism, but other causes, not immediately obvious, may be involved.
The “portable” whole-body counter was used to
obtain the gammaspectra of 110 Marshallese, half
of whom hadbeen exposedto thefallout in 1954.
No significant difference in body burdensof the
gamma-emitting radioisotopes was observed between the Marshallese exposed to fallout in 1954
and those of the comparison populationliving in
the same environmentfor the past 4 years.
as for adults, male and female. Wide variations in
levels of contamination in any group were found,
apparently dueto differences in diet and metabolism. The mean Cs'** body burden in adult males
was 14.7 muC/kg, which is not significantly different from the mean value of a similar group obtained 2 years ago; it was 300 times that of the
medical team, who were measured at the same
of residual activity was still present after the subtraction of K*° and the above radionuclides from
the total spectrum. The mean level of urinary
excretion of Sr’? was 7.2 wuC/l or 14% higher than
measured in the 1959 medical survey.
Thoughthe acute effects of radiation exposure
in the Marshallese have largely subsided, it is possible that certain late or delayed effects mayoccur.
Some late effects have already been observed in
the Japanese, such as an increased incidence of
leukemia and possibly other malignancies and also
development ofcataracts. Still other late effects
have been observed in irradiated animals. It is unhkely that such abnormalities will develop in the
relatively small Rongelap population and, should
they develop, the incidence should be quite low.
Nevertheless, it is extremely important that further surveys be conducted to detect subtle changes
associated with the development of such abnormalities so that they can be documented and
therapeutic proceduresinstituted whenever possible. The examinations show somefindings which
persist in the exposed people, and these need to be
carefully followed. These include incomplete recovery of certain blood elements to levels found
in the unexposed people, retardation of growth
and developmentin someofthe irradiated children, and pigmented changesatthe sites of radiation burnsof the skin.
Recognizing the importanceofthese surveys, the
Trust Territory of the Pacific Islands and the USS.
Atomic Energy Commission have agreed that annual
medical surveys of the Marshallese people exposed
to fallout in 1954 should continueindefinitely.