+ ee
In Project 3.2 the apparent craters formed by the]
= __
a
_
given in Table 2.8,
,
In Project 3.3 a study wasmade of tree damage on Eniirikku, Rukoji, and Chieerete Islands from the:
shots. Graded damage was observed, but data obtained
are yet to be analyzed and interpreted.
Project 3.4 determined the effects; {upon naval mines of various types
a
7
>_>
detonations were measured by fathor:-ter soundings as originally planned. The reselts ace
planted at distances of 2000 to 15,000 ft from the detor.ation site. Graded damaze was obtained
from 0 per cent at 15,000 ft to 100 per cent at 2000 ft. _
Project 3.5 was activated immediately after the[shot to document the unexpected
damage to the camp on Eninman and certain instrumentation shelters near Ground Zero, This
was done primarily by photography.
tT
—-
uo
2.3.4
—.!
Program 4, Biomedical Studies
These studies represented the first observations by Americans on human beings exposed to
excessive doses of radiation from fall-out. The groups of exposed individuals are sufficiently
large to allow good statistics. Although no preexposure clinical studies or blood counts were
available, it was possible to obtain Marshallese and American control groups that matched the
exposed population closely with regard to age, sex, and backgrourd. Thus the conclusions
which may eventually be drawn from group comparisons should be reliable.
The type of radiation received, and the manner in which the radiation dose was delivered,
differed in several important respects from that seen in the Hiroshima and Nagasaki casualties,
the Argonne or Los Alamos accidents, or in the bulk of animal laboratory radiation exposures.
In addition te a wide spectrum of gamma-ray energies in the fission-product field, there wea beta component, Some clinical, and especially laboratury, findings in this study are consi-:ent with a hard penetrating compouegat. The clinical and pathological findings in the skin
lesions, as well as the correlation of distribution of the lesions with exposed skin areas, are
consistent with a sizable component of extremely soft radiation. The absence of evidence of
skin damage deeper than the superficial lesions in the initial biopsies described would argue
against a considerable componentof radiation of intermediate energy. In addition to external
radiation, some internal contamination did occur. The extent and long-term significance of
this interval component remains to be evaluated.
_ Therefore it is probable that the exposed individuals were subjected to essentially three
types of radiation: penetrating total-body exposure, beta or soft gamma exposures of the skin,
and irradiation of internal organs from radioactive materials in the body. It remains to be
evaluated if the various findings observed can each be attributed to one of the different radiation
components separately, or if combined effects of these radiations must be invoked to explain
some of the findings. There is no good reason to date to suspect possible combined effects
from the over-all clinical or dermatological picture observed.
As stated, the meager preliminary information on the skin biopsies taken in the present
studies indicates that skin damage was limited to the superficial layers. To date, none of the
vascular lesions reported by Lushbaugh et al. as being characteristic of experimental beta
23