Cc.
The Hot Particle Problem
It is important to recognize that the ICRP has given
no guidance with respect to nonuniform irradiation of the luna
by insoluble alpha-emitters such as insoluble plutonium
particles.
In its Publication 9,
the ICRP states:
...In the meantime there is no clear evidence to show
wheth-x», with a given mean absorbed dose, the bioloyical
risk associated with a non-homogeneous distribution is
greater or less than. the risk resulting from a more
diffuse distribution of that dose in the lung. 29
In effect,
the ICRP is saying that there is no guidance as
to the risk for non-homoqgeneous exposure in the lung, hence
the MPC, and the MPLB are meaningless
particles.
for insoluble plutonium
af
The NCRP offers the
following and similar statement
with respect to these particles:
(210)
The NCRP has arbitrarily used 10 percent of
the «cleme of the ortan as the significant volume fer
irradiation of the gonads.
There are some cases in
which choice of a significant volume or area is
virtually meaningless.
For example, if a single
particle of radioactive material fixed in either lung
or lymph node may be carcincegenic, the averaging
of dose either over the lung or even over one cubic
centimeter may have little to do with this case. 30
This hot particle problem is also well recognized in
the biological community.
The following is extracted from a
239/
ICRP Publication 9, Op.
30/
NCRP Report No.
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