Dr. N. F. Barr
-2-
January 10, 1973
coprecipitation. Sediment cores must also be processed according to
the information needed from the samples, f{.e., a depth distribution
of activities throughout the cores or associations of separate radionuclides on various particle sizes can not be determined after the
cores have been homogenized. The most critical areas of concern
in preprocessing are in the bioassessment of associated radioactivity.
Specifically two cautions sre registered. One, the tissue distributions
- of each radionuclide is important therefore each macrosample should be
dissected (questioned on page 25) into body parts, i.e., muscle, bone,
skin, liver, etc. Two, the food web is best evaluated by Looking at
stomach contents in opposition to referenced food chain sequences,
e.g., turtle grass--sea urchins--starfish.
Radionuclide Analyses: We strongly urge thet all samples be eveluated
by gamma spectroscopy for expected activities of expected radionuclides
(page 29 Ic).
Also, after dissolution of sample I suspect that Fe>
and Ni63 are important enough in total body burden that the extra
effort spent in wet chemistry processing is well worth it.
William 0. Forster
Marine Scientist
Ecological Sciences Branch
Division of Biomedical and
Environmental Research
EcSB
orricep |. EcSB
"C>Bsss]CECSBOOT
WE
enamep |WOForster:cmd|JSwinebroad| fee
wep |L/20/73|78
wv. 9-53) AECM 0240
gro
o43-—16—31465-1
445-678