.
- 12 -
these tissues.
This energy produces chemical changes in
the molecul2 of the cells;
for example, such a chemical
chance coulc be a mutation in a gene.
The radiation dose
is actually a measure of the energy transferred to or
adsorbed by the tissue.
rad
The basic unit of dose is the
(one rac represents the absorption of 100 ergs of
energy per cran of material).
.
In acSition to X-rays, radionuclides emit gamma rays
. X-ravs), beta particles
particles
(helium nuclei).
(electrons), and elpha
In radiobiological experiments,
iti was determined that, while these various types of radiation
produced <=ne
same biological effects,
such
as
cancer,
masnituce cf the effect was not the same per rad..
example,
it was
found
that 100
rad of alpha
the
For
radiation vould
prosuce rourtnly 10 times as many cancers as 100 rad of
Moreover, it was found that because of the srecial
ich Pu-239 deposits in the bone, its alpha varticles
were 3 tines more effective in producing bone cancer tran the
Tha
“MELD
.
7
iron radium .
is civen
ation
tne,"
.
To account for these differences
in rem in Tables
I
and
II.
Tha
ll, "A Peview af the Radiasansitivi
Perqamon Press, Mev York, N. Y.
19
rr
-
.
oe
alona particles
:
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