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5. Analytical Results
5.1 Relevant Information from Early Surveys
5.11 Radioactivity of reef fishes of Belle Island,
Eniwetok Atoll, April 1954 to November 1955.
Exami-
nation of the data presented by Welander (1957) in a report on
the gross beta radioactivity of Eniwetok reef fishes following
the 1954 series of nuclear tests in the Marshall Islands, yieldal
some information from which inferences could be drawn which
would have a bearing on the problem of the distribution of fallout radiozinc with respect to the marine life in the lagoon:
{1) The decline in the radioactivity in fish collected
after the first 100 days after a shot was
Sue than in muscle,
and
(a) less in liver tis-
(b) greater in omnivorous than in car-
nivorous fishes.
(2)
The coefficient of variation of radioactivity in reef
fishes from the same collection differed between families of
fish.
It was significantly higher in goatfish and mullet than
in 10 other families represented in the collection.
(3) Radiochemical analyses performed within two months
on fish collected 2-3 months after a shot showed that the
induced radioactive transition element isotopes Mn>4,
co?’,
co°8,
Fe,
Co°? and zn®> were present with Fe 55 and Zn 65 as the
dominant radioisotopes.