About 50 hours after the "shot", the Navy removed the 64 Rdngelap
residents from the Atoll to the medical base at Kwajalein (Sharg &
Chapman, 1957; Cronkite et al, 1956)
Also, eighteen visiting
Rongelapese were removed from Sifo Island, Ailingnae Atoll, and[i57
Utirik people from Utirik Atoll. It was immediately recognizedithat the
surveillance and care of these people required far more profess{jonal
staff than the base could supply, and a special medical team hufriedly
organized for this purpose in the United States, utilizing naval and AEC
personnel, reached the base 8 days after the detonation.
Consistent with a whole-body dose of 190 rem (over two day
two-thirds of the Rongelap group experienced nausea, 10% with v
and diarrhea, which cleared within three days or so, and ail s
depressed white-blood-cell counts (Cronkite et al, 1956). As
the skin dose from physical contact with fallout, about 70% de
skin lesions of widely varying severity after a latency period
three weeks. Most of these were to heal successfully but a fe
significant scarring.
result of
loped
f two to
developed
The most "significant" part of the initial exposure produ
immediate signs or symptoms. A half-dozen thyroid-seeking rad
entered the body through fallout-contamination of food and wat
the course of the following weeks these iodine and telluriun
radionuclides delivered doses that eventually caused thyroid h
and the appearance of thyroid tumors.
The Bravo test posed new dosimetry problems, only vaguely
before. Owing to the gigantic energy-yield at ground level, g
quantities of coralloid radioactive material were generated (E
and Nagasaki had involved high air-bursts): 142 radionuclides
involved whose radiations and rates of decay varied greatly, a
eventual effects depended on the weather conditions and the lifi
of the exposed population.
At the time of evacuation, the exposure rate in Rongelap
1.2 - 2.3 R/hour. The whole-body dose of "175 R in air” repor
was approximately correct. The dose estimate for the thyroid
however, was much too low because only iodine-131 had been co
the calculation. As a result, the appearance of thyroid dise
was quite unexpected.
ed in 1956
land,
idered in
e later on
An upwards revision of thyroid dose was reported in 1964
lodine-133 and iodine-135 were included.
(James, 1964).
The
1984 (Lessard et al, 1985; Lessard, 1984a), based on a compre
planned attack on the problem (Bond et al, 1978), put the mea
whole-body dose at 190 rem. The revised total dose to the th
including contributions from all seven important radionuclide
greatly increased and varied significantly with age at exposu
-~- from 5,200 rem for a one-year old to 1,600 rem at age 14,
nd 1,200
rem for the adult male. It was estimated that 95% of the thyr id dose was
received during the first three post~exposure weeks, and 100% within
three months (Note 4).