CESIUM-137 AND STRONTIUM-90 RETENTION
FOLLOWING AN ACUTE INGESTION
OF RONGELAP FOOD
EDWARD P, HARDY, Jr.,* JOSEPH RIVERA,* and ROBERT A. CONARDT
*Health and Safety Laboratory, U. 5. Atomic Energy Commission, New York,
New York, and fBrookhaven National Laboratory, Upton, New York.
ABSTRACT
Marine and plant foods used by natives living on Rongelap in the
Marshall Islands contain higher levels of long-lived fission-product
radionuclides than do diets of people living in the United States due to
residual contamination from fallout in 1954. During the 1963 medical
survey of the Rongelap population, three food items indigenous to the
Rongelap diet were brought back to the United States and consumed
over a Seven-day period by a member of the medical team. The inges-
tion of these foods introduced levels of *Srand "Cs which were 20 and
60 times higher, respectively, than in the normaldiet and was therefore
considered in terms of an acute intake of two fission-product radio-
nuclides that are important from a radiological standpoint. Urinary
and fecal collections were analyzed separately, and whole-body ‘*’Cs
measurements were made with a whole-body counter. The urine was
the principal excretory route for the '*’Cs, whereas the feces was the
main removal means for the “Sr. The retention of "Sr could be
represented
by a Series of exponentials, whereas the retention of
cesium as determined by whole-body counting indicated that a single
long-term component with a biological half-life of 74 days describes
the removal process. Reasonably good agreement was obtained be-
tween retention as determined by whole-body counting and by excretion measurements. It is estimated that about 25% of the “Sr from the
Rongelap food was retained by the body at the end of 190 days. The
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