- 29 -
SUMMARY
ie collected
ands of the
[ia
The rate of decline of radioactivity in the algae at Eniwetok Atoll
r detonation)
was studied for a period of two yearg after the detonation of May 14,
asis of mixed
1954 (Nectar).
re been con-
was 1.9 wc/kg of wet tissue; this level was attributed to radioactive con-
adioisotopes
reas
The average pre-Nectar level at Belle Island (Bogor-bogo)
tamination from the tests at Bikini Atoll in March 1954.
should
After the Nectar
| test the average level in the algae built up to 2500 ye/kg on May 15,
up different
1956,
then declined to 0.10 uc/kg on April 26, 1956. A logarithmic plot of the
levels at each date of collection gave a negative slope of approximately
ittom sedi-
1.5; this slope probably could be used to estimate the average level of
howed that
radioactivity of the algae at any future date up to about four years after
to 140 feet at
the Nectar detonation.
The radio-
The rate of decline of radioactivity in water
samples collected in the same areas as the algae samples paralleled
site of deto-
that of the algae, but the levels were much lower.
by transport
Comparison of radioactive decay rates of individual algae collected
he bottom of
at Belle Island showed that Udotea, a semicalcareous alga, had selected
ns near its
radionuclide mixtures different from the ones taken up by other algae.
SeteET ae we7
Decayrates of algae and water samples collected at Belle Island
Showed that for the first two months after detonation the algae had selected some of the longer-lived isotopes from the water.
There were no differences in the amounts of radioactivity in the
| algae collected at different parts
ferences
in the
of Belle Island,
but there were aif-
amounts in the algae collected at different islands of _
a
vee
Coys,
ee eT 7
oyhk
°
1
1
.
4
7