aN
3lcs AND “Sy RETENTION FROM RONGELAP FOODS
The net absorption
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(intake—fecal excretion expressed as percent or
intake; was 30:0, a factor of 2 higher than the average for 10 normal
acults on a high-calcium diet reported by Spencer et al.*! The low
fecal calcium excretion found in the present study was indicative ofa
sizn Sy absorption.
Although me retention curve for Sr shows that the biologica
neli-lie varies with time after exposure, the data do not fit a power
function 2s found by others.'8-"° If it had been possible to measure
excreta over a longer period of ime, a power function may have been
described.
SUMMARY
The Cs and the “Sr body burdens of people living on Rongelan
island are high compared to most other populations of the world. The
season for this is that the natives consume foods that are contaminated
with long-Lved fission-product radioactivity resulting from a fallout
incursion in 1954. Their *"Cs boay burdens are comparable to those of
people living in other limited areas such as Lapland and northern
Alaska where unique ecological conditions are conducive to high Bos
concentrations in indigenous Zoods. The metabolism of “Cs and “Sr
has
been studied in the
Lapland and Alaskan groups but not :n the
Rongelap natives.
Since facilities for a metabolic-balance study were not availoble
on Rongelay Island,
several native food items were brought back to
BNL and consumed by one of the authors under controlled conditions.
Jrinary and fecal specimens were collected and whole-bocy counting
measurements were made over a period of 180 days. The intake of “Sr
over a Seven-day period was 20 times aigher than normal and that of
cs was 60 times higher than normal.
Fifty percent of the ingested “"Cs in the Rongelap food had been
excreted in urine after 85 days, whereas 14% had been eliminated in
feces during the same time. In contrast, most of the “Sr was unabsorbed. Fifty vercent had been excreted in feces at 10 days, whereas
only 2%% had been excreted in urine. The retention of "Cs as de-
termined by both whole-body counting and excretion measurements
snowed a biological half-life of 74 days. Strontium-50 retention asa
function of time was best described as a Series of exponeniials and
approached a value of 25% after 140 days.
,
These findings fall within the range or results of many other
Studies conducted under a wide variety of natural, accidental, and
experimental conditions.
ACKNOWLESGNENTS
The authors are grateful to Jonn Anxain of Rongelap island for
collecting and preparing the native foods. We wish to thank Stanton
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