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Thvroic Absorsed Dose Assessment for Rongelap and Utirik Residents
-t.
Lessard,
J.R. Naidu,
8.2. Miltenberzger
3reoknaven National Laboratory
Safety and Environmental Procection Division
Upcon, New York
11973
&
N.A. Greenhouse
University orf California
Lawrence Berkeley Laboratory
Berkeley, California
947290
&
L.V. Kaplan
Brookhaven Summer Studente Program
3rookhaven National Laboratory
and Yale University
ABSTRACT
The internal thyroid absorbed dose From Castle Bravo fallout affeccsng Rongelap and Utirik Atolls, Marshall Islands,
sidecendent approaches encompassing 1)
is reassessed using
che single zooled urine radio-
chemical analysis of March 1954 and currence uptake, recention and excrecion.
models, 2)
airborne concentrations and areal activities of the todine
isotopes derived from historic soil samples and, 3)
and areal activities of
adrborne concentrations
the todine tsotopes derived from weather cata ob~
tained during che thermonuclear test experiment at Bikini Atoll and current
tallout deposicion models.
Factors such as solubility of fodine isotopes,
the possible contribution from neucron induced activity, the impace of thyroid seekers other than iodine tsotopes on dose, and confidence levels for
values of derived quantities such as airborne activity concentrations are
also considered.
Additionally,
these thyroid absorbed dose estimates are
compared to the incidence of thyroid nodules reported for che accidencaliy
exposed people.
2esearch carried ouc under the auspice of the U.
under Contract No. DE-AC92-74CHOO016.
S.
Departmenc of Energy