410354
Status Report:
Duse Reassessment for Populations on Rongelap and Utirik following exposure to
fallout from the BRAVO incident (March 1, 1954).
Introduction:
Incidences of thyrvid nodules, benign and malignant, in the exposed populations
of Utirik and Kongelap has indicated critical differences in correspondence between
nodule incidence and thyroid dose for the populations (Table 1). The estimated
external dose received from the tine fallout began to the time of evacuation shows
that the Rongelap population received an external dose (175 rads) which was ubeout
}3 times chat for the Utirik population (14 rads), and the thyroid dose was about
10 times larger, whereas the incidence of thyroid nodules in the two populattous
were not significantly diiferent.
A preliminary study has indicated that the critical area of investigation that
could shed light is the period during fallout and evacuation for both the islands.
In addition, the fact that the Utirik population returned within 120 days folluwing
evacuation, whereas the Rongelap population returned only aftet three years, requires
that we look closely at the Utirik population in terms of a longer exposure period,
beth internal and external.
Further studies would,
therefore, have to concentrate
on the reexamination of all available data in reports issued by various agencies
vuring that period, consultations with scientific personnel involved at that time,
idencifying the areas of uncertainty, and using appropriate computer programs to
analyze the data. The end result will enable us to look for correlations between
the incidence of thyroid nodules anda the reassessed dose estimaces.
Objective:
To examine the external and internal dose estimates to the Rongelap and Utirik
populations following the "Bravo" test in order to:
—_—
a.
b.
c.
increase the confidence in the reported values
tese the hypothesis that radiation effects can be translated
into meaningful dose estimates
look for correlationship between the thyroid cancer cases and the
reassessment dose estimates (if any).
Method of Study:
1.
Literature Search:
such as;
a.
b.
c.
2.
This would require examining the various research reports
Weapon Teste (WT)
Naval Research Defense Laboratory (NRDL) Reports
Reports fros various other laboratories (University of Washington, etc).
Personnel Contacts:
Efforts will be made to contact as many of the scientists
and technical persons, who were involved in the early years for information
on measurement techniques and analytical procedures.
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