- 22 -
in the same localities, indicating that the algae had selected some of
the longer-lived radionuclides.
analyses have
Unpublished results of radiochemical
shown that Ce144- py 144
Zr95-Nb95,
and Ru'06_Rp106
are the predominant radionuclides present in algae samples collected
shortly after a nuclear detonation.
The decay rate of water samples collected in July and September,
1954,was slower than that for the algae, but because of the high percentage counting error in the last counts of radioactivity in water
samples, these data
Table 7.
are in doubt.
Decay rates of algae and intertidal water collected at Belle
Island, May 1954 to March 1955, expressed as the negative
slopes of logarithmic plots: Ay 2 A,t™™.
Dates of collection
Sample
Halimeda
5716-22
6/1-19
1.3*
1,3
_1954
7/5
9/7
10/5
11/30
1/18
1.3
1.3
1.1
1.3
1.2
1.1
1.1
Caulerpa
Spyridia
1, 2*
1,2
Udotea
1. 2*
1.3"
1.8"
1.8%
Intertidal
water
1.2
1.2
1.1
1.5"
1.2*
1,.2*
1.0%
1.1
*Two or more samples with identical slopes
=
4
ul
t
*
"
=
>
A,
Activity at day
Activity at day 1
Time in days
Slope
t
1955
2/9
1.0
1.0
1.2
0.8%
1.2
3/21
1.2
1.0