CHAPTER IV
Internal Contamination of Animals
At the time of the fallout on Rongelap
Island there were a variety of animals present.
These wereleft to live on the island, and rep-
resentative numbers were collected on the 8th,
25th, 33rd, and 5lst-53rd days and then
sacrificed. Tables 36, 37, and 38 show the
relevant data concerning external doses to the
animals while living on the island, and an
analysis of their internal contamination®
Over 90 percent of the activity in the body
of animals was in the skeleton. At 82 days
past detonation, 62 percent of the skeletal
beta activity of the pigs was due to Sr®,
7 percent Ba, and 10 percent rare earth
group.
However,
it
was
reported
that
“, ..In the 6 months period post detona-
tion
neither significant
gross
changes nor
pathological changes which could be definitely
ascribed to radiation were detected in any of
the animals.” ®
Table 39 shows the activity of a rooster and
rats collected 2 years post detonation. The
gross activity in this rooster was 40 percent
of that of a rooster from the samelocality at
1 year post detonation.
Since these animals represented interesting
eases of living continuously in a heavily contaminated environment, a strontium-90 anal-
ysis was madelater of some rats and a rooster
collected at the 2-year period. (Table 40).°
Additional analysis was made by AFL of a
single rat bone specimen (Table 40). These
data are extensive but do indicate the relatively low body burden of strontium-90.