not be discussed here.
A reassessment of thyroid absorbed dose from the initial
1954 exposure is currently being made and will be reported in a separate study.
Since April 1978, the bioassay program and whole-body counting studies have been
performed by members of the Safety and Environmental Protection Division of
Brookhaven National Laboratory.
Reports of their findings may be found in
Gr77a, Gr77b, Le8Qa, Le80b, Mi80, Mi81 and Na80.
The report by Lessard (Le80b)
contains more detail on the development of the equations used here.
The Utirik and Rongelap inhabitants were returned to their home atoll in
June 1954 and in June 1957, respectively.
The earlier repatriation of Utirik
Atoll was based on the low measured level of external radiation exposure over a
3 month observation period.
The Utirik population was subsequently examined by
a Brookhaven medical team during 1957; 144 people received comprehensive physical examinations.
In 1957,
the Rongelap inhabitants were also returned to the their atoll te
occupy new homes, community structures and other facilities which had been
constructed during their three year residence at Majuro and Kwajalein Atolls.
Following the 1957 medical survey, measurements were made on two men from Utirik
Atoll using the whole-body counter at Argonne National Laboratory. Radiochemical
analyses of their urine samples were also made.
Four persons from Rongelap
Atoll also visited Argonne for whole-body counting in 1957.
In addition, pooled
urine samples from both atoll populations were analyzed radiochemically for
137
Cs and
90
Sr.
The body burdens measured at Argonne National Laboratory were
corrected for ten days of biologic elimination and radiologic decay in order to
estimate the body burden while living on the atoll.
Starting in May 1958, Conard and Cohn (Co59), measured whole-body levels
of 1374,
6520,
and 6065 in about 100 Rongelap adults,
adolescents and juveniles