63
hypothyroidism in the two most growth-retarded
boys with subsequent growth response to thyroid
hormone treatment. Thyroid function tests in
cases with thyroid abnormalities also indicated
reduced thyroid function in someother children.
Preliminary indications are that thyroid hormone
treatment instituted in the exposed population in
September1965 is having a beneficial effect in re-
ducing thyroid nodules and stimulating growth of
children. The importance of these thyroid developments in the Marshallese is discussed.
OTHER STUDIES
Hematological studies show that the leukocyte and
platelet levels of the peripheral blood of the ex-
Laat, |
posed Rongelap people seem to have recovered to
levels equal to those of the unexposed population.
Nal (TI) crystal in a portable shadow-shield type
of counter. The Rongelap residents exposed in
1954 and the unexposedresidents were indistin-
guishable by this method, both groups showing
elevated '*°Cs body burdensof 10 to 20 nCi;kg
body weight, orslightly less than 1 Ci total body
burden and about ooo this much for °°Co body
burdens. These levels are about the same as
or slightly lower than those reported previouslyfor
the 1961 survey. Urine specimenswere also ana-
lyzed radiochemicallyfor °°Sr and '°’Cs, The °°Sr
levels remain nearly the same as those found in
1961. In a comparison of the ***Cs excretion rate
with the body burdens, a mean fractional excretion rate of 0.00553/day was found.
The blood levels of the Utirik population showed
Acknowledgments
blood cultures showed a low incidence of 2-hit
was necessary to carry out these surveys successfully. The authors are deeply grateful for valuable
no obvious abnormalities and were similar to those
previously noted.
.
Chromosome studies of white cells of 51 peripheral
aberrations in the exposed people which was quite
significant in view of the absence of any such aber-
The cooperation of many agencies and persons
assistance to many individuals too numerous to
name. Weare particularly grateful to the people
rations in the comparison population.
Blood volume and red blood cell volume studies showed
that people of Rongelap havesignificantly reduced levels as compared with Americans. Cau-
of Rongelap and Utirik Atolls for their cooperation in these examinations.
Manyofficials of the Atomic Energy Commis-
erally show this phenomenon.
ogy and Medicine, and Mr. W.A. Bonnet and Mr
casiansliving in the Marshall Islands did not genAging studies have been repeated with the addi-
tion of several new parameters.(vibratory sense,
light extinction test, body potassium levels, and
blood serum cholesterol) and with morerefined
Statistical analysis. Curves of response for each
aging parameterand anover-all biological age
score curve are presented. Nosignificant increase
in aging effects in the exposed population compared with the unexposed population could be detected. The over-all correlation of the biological
age scores with chronological age was good. It was
concludedthatthe tests employed may not have
been sensitive enoughto detect subtle effects of
aging at this exposurelevel.
sion, particularly Dr. Charles L. Dunham and Dr
H.D. Brunerandtheirstaff of the Division of BiolNeil Rassmussen of the Honolulu Operations Of-
fice, were most helpful in coordination of arrangements and in supporting the surveys in every wav
possible.
Weare grateful to the officials of the Department ofthe Interior, particularly Mrs. Ruth Van
Cleeve and the officials of the Trust Territory
of the Pacific Islands, including High Commis-
sioners Mr. W.M. Goding and Mr. W.R. Noorwood; the Acting Director of Medical Services.
Dr. L.A. Howe; the District Administrator for the
Marshall Islands, Mr. Dwight Heine, and his As-
sistant, Mr. Danny Akimoto; the Director of the
Majuro Hospital, Dr. John Iaman, and members
of his staff; the Trust Territory Representative at
ESTIMATION OF INTERNAL BODY BURDENS
OF RADIONUCLIDES
In the 1965 survey whole-body counting was
done on 179 people with an 11'%-in.-diameter
Kwajalein, Mr. R. McKay, and Dr. Ezra Riklon
at the Ebeye Hospital; all were most helpful.
The Pacific Missile Range Facility at Kwajalein
wasofgreat assistance in furnishing necessaryair-
lifts and materials. Mr. Frank Granich and others