TABLE V
Occupational Exvesure Guidance
for Insoluble Alpha Emitters,
;
-_,
;
.
Maximum Permissible Lung Particle Burden
Cancer risk due to 5 rem/yr
whole body exposure
(MPLPB)
77
Assumed Risk in Particle
1/1000
1/2000
1/10,000
4.5x1074
0.45
0.9
1073 (best estimate)
1.
2.
10.
2.3x1073
2.3
4.6
23.
largest MPLEB in Table V,
23 particles,
4.5
represent a
reduction of the existing MPLB and MPC, by a factor of
10,000.
It is recommended here that the best estimate of
the effects of uniform exposure by the BEIR Committee be used
together with a risk of cancer induction of 1/2000 per hot
particle in determining the MPLPB for insoluble alphaemitting radionuclides in hot particles.
This
is a somewhat
arbitrary compromise and is not the most conservative value
that could be
recommended.
for occupational exposure
Thus,
the
recommended MPL?PB
from hot particles of alpha-
77/
The number of particles required to give a cancer risk
78/
Source:
equal to that from uniform radiation.
BEIR Report, Op. cit., p. 91.
The MPLPB
corresponding to a lung cancer risk of 3xl07> due to 15 rem/yr
lung dose [BEIR Report, Op. cit., p. 156] are 0.03, 0.06
and 0.3 for assumed particle risks of 1/1000, 1/2000 and
~~
¢
on
.
*
~
1/10 ,000 respectively.