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TABLE V
TO PLUTONIUM BY INHALATION
ESTIMATED ACCUMULATED AVERAGE ORGAN DOSES FOR PERSONS EXPOSED
The
Time since Exposure
mal
Estimated Exposure
(years)
(MPL)
as
the
is
odel
rtain
veror
as
Accumulated Average Organ Dese®
Bone (rads)
Liver (rads)
Lung (rads)
80
24
1.4
6.7
37
24
1.4
6.7
37
80
24
1.6
7.6
42
90
24
1.8
8.6
47
100
ah
2.0
9.6
53
110
2.3
11.0
61
130
24
2.5
12.0
66
140
24
3.3
16.0
87
190
oh
gham
11
,
24
3.4
16.0
90
190
24
3.6
17.0
95
200
23
1.1
5.0
28
63
23
1.1
5.0
28
63
4-hese values are being brought up-to-date using the latest values for the body burden.
This is a subject
of a future report.
ter
bone maximum permissible level (MPL) = 0.04 UCi.
sige oy
hort
RN negRS ONgr IEARNToteae
ing
these studies has been carried out at the Univer-
1
sity of Utah Medical School. 2
on
10te
Luce
ites
age
ther
,oOne
These observations have
the first group of 6 beagles were injected (IV) with
verse biological effects (e.g., practical threshold)
below certain levels of injected plutonium.
Injected doses ranged from 0.016 to
This
2.9 pCi per kg hody weight for 6 groups of about
point has not been accepted by everyone and has not
12 dogs each.
been proven unequivocally for alpha-emitting tadio-
The first animal to die in July 1956
of an osteogenic sarcoma was in the highest dose
In 1961, an osteosarcoma occurred in a
beagle at the then lowest dose (0.016 uCi per kg),
and since then several lower dose groups have been
added to the experiment.
jJels
injected is reduced.
prompted numerous investigators to predict no ad-
239 Pu citrate.
group.
ver,
On December 1, 1952,
The lowest dose group,
0.00064 pCi per kg, corresponds roughly to the max-
nuclides .?4
C.
Determination of Piutonium in the Body by In
Vivo Measurements
1,
Plutonium in the Chest Cavity.
During the
most recent (late 197l-early 1972) medical examina-
imum permissible occupational body burden (0.04 pCi)
tions at Los Alamos, estimates were made of the
in man.
amount of plutonium in the lung and respiratory
To date, the 0.016 pCi per kg dose level is of
interest,
as 4 dogs have developed osteosarcomas,
giving a tumor incidence of 33 percent.
The aver-
lymph nodes of each subject using an tm vivo lung
counter (see Appendix D).
Figure 9 shows the pair
of detectors in position for counting the low-energy
age time from injection to death for these animals
X-rays emerging from the chest.
was 9.9 years, and the average skeletal dose from
were made of the liver region in several subjects
injection to death was estimated to be about
and of the hands of persons known to have had skin
80 rads)? (a more recent estimate suggests about
wounds contaminated by plutonium.
50 rads),
tectable activity (MDA) for human subjects measured
We do not know whether osteosarcomas will
Measurements also
The minimum de-
be produced at dose levels lower than 0.016 uci/kg
with the LASL detectors varies with several param-
and can only await the outcome of this important
eters such as body build and chest thickness.
experiment.
average MDA for a 2000-second counting time is about
However, we do know that the tumor
incidence decreases and the time required for tumors
to develop increases as the amount of
piutonium
An
7 nCi if ome uses the 95 percent confidence level.
For the 68 percent confidence level and a similar