RADIATION INJURIES


As pointed out in another section of this report the radiations from the
nuclear explosions which caused injuries to persons were primarily those
experienced within the first second after the explosion; a few may have
occurred later, but all occurred in the first minute. The other two
general types of radiation, viz., radiation from scattered fission products
and induced radioactivity from objects near the center of explosion, were
definitely proved not to have caused any casualties.

The proper designation of radiation injuries is somewhat difficult.
Probably the two most direct designations are radiation injury and gamma
ray injury. The former term is not entirely suitable in that it does not
define the type of radiation as ionizing and allows possible confusion with
other types of radiation (e.g., infra-red). The objection to the latter
term is that it limits the ionizing radiation to gamma rays, which were
undoubtedly the most important; but the possible contribution of neutron
and even beta rays to the biological effects cannot be entirely ignored.
Radiation injury has the advantage of custom, since it is generally
understood in medicine to refer to X-ray effect as distinguished from the
effects of actinic radiation. Accordingly, radiation injury is used in
this report to mean injury due only to ionizing radiation.

According to Japanese observations, the early symptons in patients
suffering from radiation injury closely resembled the symptons observed in
patients receiving intensive roentgen therapy, as well as those observed in
experimental animals receiving large doses of X-rays. The important
symptoms reported by the Japanese and observed by American authorities were
epilation (lose of hair), petechiae (bleeding into the skin), and other