tain gammaspectra on 227 people. Details ofthe
exposure and findings of these medical studies
have been reported.’~*
During the 1961 survey the portable shield was
used in conjunction with an improved detection
and data-recording apparatus. The gamma-ray
spectra of 110 people were obtained. Half the
people measured had been exposedto thefallout
suming and difficult. In 1957, several Rongelap
a a
people were brought to Argonne National Labo-
ratory, where it was demonstrated that their body
burdens of gamma emitters could be measured in
the whole-body counter. Cs'*’ and Zn*° were
shown to be the prominent isotopes in the Marshallese at that time.
The Rongelap people, originally evacuated to
in 1954; the other half were unexposed.
another island in 1954, were returned to their
homeisland in July 1957. Since-the island and the
indigenous food sourcesstill had a low level of persisting radionuclides, continued evaluation of the
body burdens in these people was of considerable
METHOD
Shielding was provided by a 21-ton room with
walls constructed of laminated '4-in.-thick steel
panels bolted together, which can be disassembled.
Theinside dimensions of the room are 5X5 ft and
6 ft high. Figure 52 showsthe steel room (as set up
for the 1959 survey). In 1961 the room wasset up
interest.
A portable whole-body counter was designed
and constructed at Brookhaven National Laboratory and transported to the Marshall Islands,
where it has since been employed during the annual medical surveys to ascertain the level of internally-deposited gamma-emitting isotopes. In
1958, 100 Marshallese people were counted, and
the procedure was repeated one yearlater to ob-
in the cargo hold of the Reque (Figure 6). Along
with the steel room,an air-conditioned prefabri-
cated wooden room 7x8 x10 ft was set up to
house the pulse-height analyzer and other elec-
Table 15
Frequencies (in Percent) of Gm Factors in Various Populations
Gm Factor
Population
No.
United States
White
Negro
Athabascan Indians (Alaska)
Artic Village
Fort Yukon
Total
303
364
98.1
x
91.8
17.5
97.5
like
0
3.0
27.7
58
100.0
0
41.4
0
51
100.0
3.9
31.4
0
100.0 Av
1.8 Av
109
Eskimos(Alaska)
Wainwright
50.8
b
36.7 Av
50
100.0
20.0
35
35
37
100.0
100.0
100.0
100.0
100.0
94.6
0
0
0
0
100.0
1-9
100.0
97.3
0
43.6
Djuka Negroes
35
100.0
100.0
0
62.9
Javanese
Oyana Indians
Carib Indians
20
15
19
100.0
100.0
100.0
100.0
86.7
79.0
15.0
26.7
52.6
50.0
0
0
Africa
Yoruba
Fulani
Bashi
Pygmies
120
Micronesia
RongelapAtoll
Surinam
oom
by
wi
a
“
pe
VGant
‘tie3
100.0
100.0
6.0
Q
0
100.0
94.3
35.1
Od 4
Le
MY;
I TE TCEEIGEIT RR RRSree SE EO AS Re IOR SRE LE Ng mp rw eae mT oe ye
+
:
ae
Av
fee tae en ae A Aene ee cmoreeae ae
”
“39