-21-
of about 0.3 ina fish (Tilapia).
re
and
scales,
however,
In the case of fish bone
the concentration factors may be higher.
In the croaker (Micropogon undulatus) concentration factors
2 eree gelwantaeMNPE
for strontium in vertebrae and scales were 2.5 and 2.1 respectively those of sea water.
In addition to the above mentioned factors,
isotope
dilution by stable strontium would result in reduced uptake
of Sr9° by marine organisms.
Stable strontium is present in
the sea at a level 6 to 1300 times that of the naturally oc-
Ts
curring forms of the other elements represented in fallout
(Table 3, column 2).
Thus the discrimination against radio-
strontium as a consequence of the presence of stable strontium in
sea water
would be 6 to 1300 times
that to which
the other radioelements would be subjected because
of the
presence of their stable counterparts.
Further discrimination against the uptake of radiostront ium
in these organisms may be caused by the scavenging action of
calcite formed from coral aragonite in fallout material.
simple experiment by the author,
pulverized coral was
In
a
sprinkled
onto and allowed to settle through sea water contaminated with
Sr39 Clo.
Approximately 11 per cent of the radionuclide
removed from solution the first hour.
was
noted in a parallel
was
No reduction in activity
control experiment.
Suito, Takiyama
and Uyeda (22) reported that the ashes from the March 1, 1954
-
eeeeee er ee
weapons
consisted
test at Bikini
of
white
which fell on the
granules
of
calcite
No. 5 Pukuryu Maru
approximately