Cook Plant preoperational studies, 1969 / John C. Ayers ... [et al.].

The largest accumulation multiple, (pCi per gram/pCi per ml.) resulting from
this experiment was 29 as observed for manganese and zinc. (See Table #3.)
Results of the experiment with sediment revealed that significant percentages
of manganese-54, zinc-65, strontium-90 were removed by the amphipods. Accumulation multiples for these isotopes were 29, 273 and 70, respectively. It was
observed also that a large percent of each isotope added became associated with
the sediment and thereby available to the amphipods.
CONCLUSIONS
The results of the experiments described above indicate that Pontoporeia
affinis has a greater affinity for zinc than any other isotope tested. It is
also concluded the accumulation of strontium and zinc are enhanced by their
availability in the sediment and that their accumulation involves metabolic
processes.
Experiments will be initiated shortly to determine maximum accumulation
multiples for radioactive strontium, zinc and manganese. Strontium-85, a gamma
emitter, will be used in these experiments to permit the simultaneous measurement
of radioactivity due to all three isotopes by gamma spectrometry. Having reached
a maximum specific activity test organisms will be placed in aquaria containing
no added radionuclides. The loss of activity in time will permit the calculation
of the effective and biological half-lives of each radioisotope in the amphipod.

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