1. Food webs - It should be recognized that the food webs are not perfectly
known, buf to move beyond what is now known would require a major effort that
probably is not needed for this program, at least for the gamma-emitting radionuclides.
Held has described the food web relationships for gamma-emitting
radionuclides in the figure, "Distribution of Fallout Radioisotopes, Rongelap
Atoll, 1061," a copy of which is attached. From information obtained at Bikini
and Eniwetok since 1961,
there is no reason to expect that there would be any
major surprises if the 1961 Rongelap model was used as the 1973 Eniwetok model.
Held's work did not include analyses for alpha-emitting radionuclides and hence
the food web studies at Runit need special attention.
2. Models - The use of models for quantitative estimates of the movement
of radionuclides through the food web will be limited by the scanty information
on transfer coefficients.
3.
Limits of detection - The limits of detection should be established
on the basis of their effects on the estimates of the total dose to the
Eniwetekese.
4. Number of radionuclides - Undoubtedly, there are a few radionuclides
in the samples that can be identified by use of involved chemical procedures
and/or sophisticated instruments. Although a complete budget of all radionuclides
present in the samples is of great academic interest, such information is being
obtained from Bikini and, therefore, for practical reasons, the decision to seek
out these radionuclides should rest on their contribution to the total dose.
3» Number of samples for specific radionuclides - All samples did not
need to ‘be analyzed for ail radionuclides. The information from previous analyses
and the use of indicator species should guide the decision about number of
samples for specific radionuclides.
In regard to execution of the program, my observation based on the December trip
to Eniwetok and our Laboratory's contract with LLL is that the program has been
well executed.
Sincerely yours,
AHS:ah ~
cc: Dr. Edward Held
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Allyn H. Seymour
Director, Laboratory of
Radiation Ecology