composition of two samples has little meaning unless the age of the
radioisotopes in the samples is approximately the same.
Thirdly, the comparison of results of analyses may require
that the samples be alike as to species, tissue and even physiological function.
Using the giant clam again as an example, there
are species living in the tropical Pacific that acquire a large
portion of their food by growing and harvesting Zooxanthellae within
their own body.
These clams have a large and specialized kidney
which concentrates radiocobalt to a high degree.
There are other
giant clams in the Pacific that are not as dependent upon Zooxanthellae and do not have as specialized a kidney.
In the clams
with the less specialized kidney more radiozinc is found than radiocobalt and this finding is in agreement with laboratory experiments
with less specialized clams
(Chipman,
1958).
Thus itwould be
inaccurate to make a generalization about the uptake of fallout
radioisotopes by clams based upon the analysis of the unusual
kidney of a highly specialized species which is common and important in only a limited part of the world.
The comparison of results of radiological analysis of marine
organisms may be used to evaluate the health hazard to man associated with eating certain sea foods.
(Man‘s concern about fallout
in the ocean is primarily as to how it will affect his health and
secondarily as to how it will affect his ocean resources).
The
health hazard problem will not be discussed here, other than to