h
showed the major portion of activity in their gastrointestinal tract.
Based on
these studies it was estimated that the amount of radioactive material in
the gastrointestinal tract of the more heavily exposed Rongelap group at 1
day post detonation was approximately 3mCi.
The initial body burdens of internal emitters in the Rongelap people were
estimated from data obtained by radiochemical analysis of the tissues of
2 pigs which had been simultaneously exposed, and subsequent comparison
of human and animal urine analyses date (Cohn et al.).
Information on the
tissue distribution of fission products was obtained from the radiochemical
analyses of the pigs living on Rongelap for 1 month.
95% was localized in the skeleton of the pig.
Of the internal activity
The pattern of deposition of —
the fission product mixture in the skeleton, as seen in an autoradiograph of
a tibia of 1 of these pigs, resembles that seen after administration of
alkaline earths, i.e. dense deposition in epiphyseal region (Figure 5).
in the first few months following the acute exposure, 895. and 11 (plus the
shorter lived iodine isotopes) contributed the greatest internal radiation dose
to the Marshallese.
895, contributed the major portion of the beta dose to the
skeleton at this time.
The highest dose to an individual tissue (100 to 160 rep)
was delivered to the thyroid by the iodine isotopes.
Table 3 shows the estimates
of the mean body burdens of the Marshallese at 1 and 82 days post exposure.
Table 2
Estimated Body Burden of Rongelap People (ic)
Activity at
isotope
__Day|
5r89
pal49
Rare Earth Group
0-1.2
t43l¢in thyroid
6.4-11.2
RuLO3
0-0.013
ca45
5001304
1.6-2.2
0.34-2.7
gland)
Fissile Material
0-0.019
0-0.016 (gm)
Activity at
_Day82
0.19
0.021
0.03
0.0
-
0.0
0.0