Since one purpose of presenting this material is to provide a more complete
background by which one might bettor uncssstcand and prophesy from animal data
wast changes may be anticipated in the blood of man after an atomic bomb explosion,
it would be desirable if the radiation from atomic bombs were uniform and monochromatic.
Unfortunately, diverse
says of varicus energies and uncqual shiciding
by buildings, heavy machinery and miscclianecous intervening objects in an urban
areca will produce a shadowing effect ond uncaucl depth coses in the body of man
and give, in mony instances, uncqual toval-body exposure to the spectrum of ionize
ing radiation produced by an atomic explosion.
In addition, the energy of the
scattered radiation will be a function of the scattering medium,
8.3
Mechanism of Injury.
The mechanism by which the collular choazes tcke place has been the
source of considerable research.
Chanses in the hematopoietic system are obvious
ly a response to the basic effects of ionizing sodiation upon protoplasm in gencre
al.
These effects are considered in separate chapters (see Chapters VI and VII).
The problem of radiosensitivity of blood cells in the pesipheoral blood in contrast
to celis in the hematopoictic organs, particularly the stem ccolls, has been inves=
tigated at lensth.
At the present tine
there is no good evidence thet the mature
ceiis in the peripheral blood are significantly affected by amounts of radiation
in the
acthal and 0-209 per cont tethol range (roughly 0-1000 © will cover ali
mannalion species), with the probable exception of lymphocytes.
All the evidence
indicates that changes in the periuheral biesd are the discct ond indisect result
of injusy to the formative ¢cclis in $ho ho:matopoictic organs.
kanges, hematopoiesis is stopped, at icast temporarily.
In the higher dose
From about the LDsg (that
dose which kitis £9 per cent within a civen time linit) down, hematopoiesis is impaired for a variable tine.