-31-
large plankton and Mo?9--T.29™ were higher in small plankton; otherwise the radioisotopic compositions were similar.
Analysis of sea water collected shortly after another underwater
detonation (Umbrella), in the lagoon at Eniwetok, showed that Np
pel32_82
Ce!43_ pr l43
and Mo?9-p¢99m were
239
’
the predominant
radioisotopes in the particulate matter (>0.45u) present in the surface
water near target zero (Table 8).
Table 8.
Percentage of gamma emitting radioisotopes in the
particulate (> 0.454) and soluble (<0. 45y) form in
sea water collected 75 minutes after the Umbrella
event (8)
Radioisotope
Particulate
108 d/m/1
Per cent of
particulate
activity
Soluble
Per cent of
soluble
106 d/m/1 activity
Np239
5.2
62.5
30.0
75.6
y237
0.02
0.2
4.0
10.1
Tel32_1132
1.9
22.3
1.9
4.7
Mo29-T¢99m
0. 48
5.8
3.1
7.8
Cel4l-pyl4l
0.028
0.3
0
Cel43-pyl43
0.66
7.9
0
Cel44.py144
0. 0028
£0.14
0
Bal40_1,4140
0.076
Some of these isotopes also
the <0.45yu fraction (Table 8),
0.9
were present
which could
0.7
in high
1.8
amounts in
include materials