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TABLE V
Occupational Exposure Guidance for Insoluble Alpha Emitters,
Maximum Permissible Lung Particle Burden (MPLPB) 7?
Cancer risk due to 5 rem/yr _
whole boay exposure /3
Assumed Risk in Particle
1/1000
1/2000
4.5x1074
0.45
0.9
107-3
l.
2.
2.3
4.6
(best estimate)
2.3x1072
1/10,000
°
4.5
£10.
23.
o
largest MPLEB in Table V,
23 particles, 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 1/2090 per hot
particle in détermining 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.
Thus, the recommended MPLPB
for occupational exposure from hot particles of alpha-
77/ The number of particles required to give a cancer risk
equal to that from uniform radiation.
78/
Source:
BEIR Report, Op. cit., p. 91.
The MPLFB
corresponding to a lung cancer risk of 3x1075 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
1/10 ,C09S
respectively.