(3) Cases of people receiving a few hundred rem. Some individuals
survive, but others die as a result of failure of blood-forming organs. These doses of
radiation have very little effect on the circulating blood. Instead, the radiation kills the
primitive stem cells in the bone marrow, lymph nodes, and spleen. These primitive cells
produce the replacements for the circulating blood.
(a) For about a month after the exposure to radiation, an individual has
brief periods of nausea.
(b) At the end of that month, the mature circulating blood cells have
reached the end of their lives and die. Because the primitive stem cells cannot produce
replacement cells, the exposed person begins to suffer hemorrhages caused by the lack
of platelet cells necessary for blood clotting. The individual becomes tired and weak
from anemia. Also, there is a risk of infection because of the absence of protective
white blood cells.
(4) Cases of people receiving 325 rem. About half of the healthy adults who
are exposed to radiation will die. Very young people and very old people may be very
sensitive to even this low amount of radiation. Some people may be saved with medical
help--antibiotics, blood transfusions, or bone marrow transplants.
e. Acute Local Irradiation. If only specific parts of the body are exposed to
radiation, the body can tolerate a higher amount of radiation. Also, much of the bone
marrow will not be exposed to radiation and can, therefore, continue to form blood cells.
For example, in radiation therapy for cancer, normal tissues can tolerate a dose of
6,000 to 7,000 rads delivered over a period of six to seven weeks. These doses may be
enough to stop permanently the growth of many cancers.
(1) Larger accidental doses of radiation result in severe tissue damage and
necrosis. (Necrosis = changes resulting in cell death.) Groups of cells or part of a
structure or an organ may be affected.
(2) After exposure to radiation has occurred, there is no known treatment to
stop the development of the injury. Sometimes dead tissue can be removed surgically.
Repair can be done by plastic surgery if the tissues surrounding the injury are not too
CONTROL MEASURES IN THE MILITARY
a. The Radiation Protection Officer. The Radiation Protection Officer (RPO),
a full-time or extra-duty assignment, is responsible for the following: