ymeon 40, concentration
10
o
3S
|
3k
®
=
£
S
2
=
®
r
B
I5Ey ~ eviscerated whole fish
Cc
'55ey - viscera
D 207.5; - viscera
207,,__
Bi | - evisc erated
E
=
1.0 or
_
,
whole fish
a
O5t//
'
O.3fF
2°
=
4
A 137, - entire fish
Vn
5
2
>a
5
_
Column legend
0.)
baad
rT
1toar
2
CHIP
© 0.05
oO
5
=
4
|
baer
i
17
m
=
eT
ATT
:
a
c
r
r
HE
my
4
~ 0.03 -
0.0)
LHALEIPIE
BELLE
alefc ET
IRENE
_FAfBICHOPES
JANET
il AU APBECHORE]
URSULA YVONNE DAVID
|
Fig. 160.
4
fapsac{Dpel
FRED
fabstchoe|
HENRY
Pap BCjoye
LEROY
Collection site
Average ST os, 135 by, and 2073 concentration in convict surgeon from
Enewetak Atoll, October to December, 1972.
all convict surgeon samples,
levels (av 15 pCi/g).
No 60 Go, 20753,
The 40% value is the mean for
60K and 20753 data for the two collection
or 135 Ey were observed, but he, 137 os,
periods.
905... and 239, 2405, were found in some
for 800, (radioactive decay half-life
or all of the samples, usually at levels
5,24 yr) and 5.1 yr for 20 "Bi (radioactive
comparable to the lower values found at
decay half-life 30 yr) implies an effective
Enewetak.
half-life in the ecosystem for both isotopes
As with the plankton, comparison of
The effective half-life of 2.7 yr
of about 5-6 yr.
data obtained from this survey with similar
Of the marine invertebrates present at
data from samples taken in 1964 indicates
Enewetak, tridacna clams,
that, for some nuclides at least, there are
bers, spiny lobster, and top snails were
processes operating to reduce concentra-
collected and analyzed.
tions in the lagoon faster than is expected
80K was the most abundant radioisotope
from radioactive decay alone,
found, and it was present in higher
Table 220,
for example, presents a comparison of
sea cucum-
In the tridacna,
amounts in the kidney than in the viscera,
II-24