tt ME Bete Ek
2 sheila! Salibaile wn sete, et
ABSTRACT
Radiochemical separations were made on plankton samples
collected in and west of the Eniwetok Proving Ground in Sep-
tember
1956.
Ion exchange resin column and precipitation
technicues were used.
Fisston products, mainly Zr?9-Nb25
and Cel44-prl44, contributed an average of 29 per cent of
the total radioactivity.
The remaining 71 per cent of the
activity was contributed by the non-fission radioisotopes
zn©5, Co57,58,60, Fe55 and Mn?+,
Radioactive zinc, cobalt,
and tron accounted for averages of 24, 26 and 21 per cent
respectively of the total radioactivity.
in trace amounts.
Variations
Mn>4 was present
in ratio of occurrence for
the different non-fission products with change in geographi-
cal location was observed.
Relatively high levels of gn©5
were centered in the area near Bikini and Eniwetok Atolls.
The area of high levels of radioactive cobalt and iron in
comparison to gn©5 was located approximately 480 miles west
and slightly north of Eniwetok Atoll.