wn
CHAPTER 4
INTERNAL CONTAMINATION OF FISH, MARINE
SPECIMENS, AND BIRDS
Fish and birds were collected from the following islands of the
Rongelap Atoll: Rongelap, Gejen, Kabelle, and Labaredj. In addition,
other animals were collected from Bikar, Likiep and Utirik Atolls and
Eniwetsk Island of the Rongerik Atoll. The majority of the marine speci.
mens were collected in the lagoons off the shores of the islands. The
larger fish were caught inthe middle of the lagoon.
Most of the fish were collected after they were poisoned by a Rote.
none solution dispersed in the shallow water. The birds (terns) were
shot with a rifle. Each specimen was placed in a plastic bag and frozen.
The frozen samples were transported to this laboratory.
4.1
LABORATORY PROCEDURES
A number of the large fish were completely separated into skeleton,
muscle, gills,
liver, and viscera.
invertebrates were analyzed whole.
The remaining fish and marine
All samples were dried at 100°C for 48 hr and ashed for 48 hr at
550°C. The ash was dissolved in 2N HC] and made upto volume. The
gamma activity was counted in a deep-well, sodium iodide crystal,
gamma Scintillation counter; the beta activity was counted under a thin
end-window, beta counter.
The beta activity in each case was corrected
for counter efficiency and mass absorption. The gamma and beta activity is recorded in "pc {Co equivalent)". This unit was derived from
comparison with a Co standard counted under identical conditions as
the samples.
DOE ARCHIVES
Radiochemical analysis were performed to determine the concentra-
tion of several radionuclides in a number of the specimens.
The radio-
chemical techniques employed will be described in a forthcoming report.
-15-
370
24
24