irradiation received and since such a small population is involved the
probabilities are good that such effects will not be observed in the
Marshallese.
4, Ophthalmological changes related to late effects of radiation
(. 8,20) have not been seen,
Silit-lamp observations over the past 4 years
have revealed no polychromatic plaques or cataracts.
No differences were
found in visual acuity in the exposed and unexposed children.
5. Genetic effects.
been conducted.
No specific studies for genetic effects have
However, no abnormalities have been noted in the 15 babies
born of irradiated parents.
In view of the generally negative findings in
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the studies of the first generation offspring of the irradiated Japanese (19)
it is unlikely that genetic studies in this group will be fruitful.
6. Beta irradiation.
«©.
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5
4
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No late effects of beta irradiation of the
skin such as chronic radiation dermatitis or pre-malignant or malisnant
changes have been found in the Marshallese.
7. Body burdens of radioactive isotopes.
{
The present body burdens
of radioactive isotopes absorbed from both the initial contaminating event
and from the present habitation on Rongelap are far below the accepted toler-
ance levels and the hazard from this exposure is unlikely to result in any
late effects.
Even though as pointed out, the radioactive contamination of
Rongelap island is considered perfectly safe for human habitation, the levels
of activity are higher than found in other inhabited locations in the world.
The habitation of these people on the island therefore affords a most valuable ecological radiation study on human beings.
Since only small amounts
of isotopes are necessary for tracer studies, the various radioisotopes
present can be traced from the soil, through the food chain, and into the
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