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The shorebirds contained greater amounts of radioactive
macerials in the different organs and tissues shortly after the
fallout at Rongelap than did the terns.
noted in 1952 at Eniweto:
(UWFL-33)).”
A similer tendency was
following Mike shot (see WT-616
However, the average levels of activity in the
organs of the shore birds decreased more rapidly with increasing
time after fallout than did those of the terns.
These differ-
ences may be accounted for, in part at least, by the differences
in feeding habits end migrational characteristics.
The average specific activities of the organs and tissues
of Rongelap terns are given in Table’ V.
With the exception of
muscle, which is consistently low compared with the other
tissues,
there is no distinet pattern of relative activities
between different organs,
Tne decline of radioactivity levels in the organs and
tissues of terns may be divided into three types (Figures 10a
and b):
(1) organs in which the decline is semilogarithmic,
half-life 40 days-- these include the muscle, liver, and
kidney; (2) organs in which the decline is logarithmic -- these
are the bone (r = t72+35) and ileum (r =
,72-85), and (3) organs
in which the variability is extremely great~-the skin and lung
represent this group.
The shapes of the radioactivity decline curves fcr the
different organs are determined by a combination of (1) avail-
ability of the isotopes, (©) total uptake and degree of selective uptake of different isotopes, (3) radioactive half-life,
and (4) biological half-life.
Since the relative effects and
al Studies ... op. cit., p. 6.
* Radiobiologic
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