Table 7.
F = a = 2S
Parameters for Calculating Radiation Doses From
Transuranium Radionuclides
SSSees ; FS
sees 2 og
Organ a)
GIT /,)
Mass, g
150
—
Radionuciide
aaah?
oat
; oe
39pu
aeee
mee
Pu
2 3Pu
a44py
241 Am
24 24m
area
eu Am
244 am
242Cm
24 30m
244m
24 5cm
746Cm
24 70m
248Cm
24 30m
24 9Bk
2 50Bk
249c¢
250CF
251¢cE
2520f
2 53c£
2545
tO)
2.4 x 106
Ln
(a)
(b)
(c}
(d)
{e)
(f£)
1010
108
105
105
0.62
0.14
0.55
0.52
0.52
0.010
0.49
0.18
1.14
0.56
0.745
0.734
0.79
0,52
0.61
0.61
0.59
0.55
0.54
0.54
11.5
0.026
0.41
0.63
0,61
0.59
2.1
0.78
120
Sarto
Bone
| 500
a
Kidney
7000
49
0.16
57
53
53
0.013
51
0.18
59
57
53.2
53.1
54.2
0.52
63
60
60
35
56
_
erpy, MeV/dis(f)_
Po
0.63
284
266
266
0.048
253
0.88
292
283
264
266
273
2.6
315
299
299
277
56
453
0.31
0.026
0.52
60
62
59
210
68
3800
278
278
2244
27
0.13
1.5
301
311
295
1100
343
18900
49
0.16
57
53
53
0.013
51
0.18
59
57
53.2
53.1
54.2
0.52
63
60
60
55
56
56
453
-
re
a
.
49
|
0.15
57
53
53.
0.012
51
0.18
59
57
53.1
53.1
54.2
0.52
63
60
60
55
56
56
453
Mass of contents of lower large intestine.
56
56
453
5.2
0.026
0.83
60
62
59
210
68
3800
lower large intestine).
ICRP-II used 1000g for mass of lungs.
All other models use 500g.
Effective energy to lymph nodes and all portions of the Tespiratory tract are
assumed equal to lung. Masses for these organs are: nasopharyngeal region,
1.35g; tracheobronchial region, 400g; and abdominal lymph nodes, 10g.
1,
1s radioactive half-life of radionuclide, days.
Includes energy from daughter products with half-times less than 1 year.
660
(32)
a
Dis the additional dose (rems)
Dd.
is
the dose commitment
(rems}.
ICRP Committee LI Model-
49
0.22
57
53
53
0.014
51
0.19
59
57
53.2
53.1
54.2
0,52
63
60
60
55
eed ee eeed
GIT is gastrointestinal tract (principally,
Cc
where
70000
ft
D=D+t+OD
ey
TB
300
- —L..
Effective En
8 x 108
2.33
33000
8.9 x 108
2.4 x 108
4800
1.4 x 108
0.208
2.8 x 10!9
1.7 x 10°
5.6 x 10"
0,667
2.9 x 108
0.0181
162.5
13000
6700
7,3 x 106
3.3 x
1.7 x
0.044
290
0.134
1.7 x
3700
2.9 x
803
18.0
56.0
Lung 6°)
additional dose from the plutonium already within the body at time T,. The
dose commitment is the sum of the dose accumulated to Ty plus the additional
dose or
The report of the ICRP Committee IT
(1959)
contained a model
and data which was
used to estimate maximum permissible concentrations (MPC) of radionuclides in
air and water. The model, as applied to plutonium or other transuranics, is
indicated in Figure 3. This model distinguishes between insoluble and readily
soluble compounds that are inhaled.
In the absence of other data, it is
assumed that 25 percent of a soluble compound is exhaled, 50 percent is
swallowed and reaches
the gastrointestinal
tract
(GIT)
almost
25 percent is immediately transferred directly to the blood.
immediately,
and
None of the soluble compound resides in the lung for any significant length of
time and,
therefore,
does not contribute a radiation dose
to the
lung.
For
insoluble compounds, in the absence of other data, it is assumed that 25
Percent is exhaled, 50 percent is swallowed and reaches the GIT immediately,
and 25 percent is immediately transferred directly to tissues deep in the
lung. Of the amount transferred to the deep lung, half (12.5 percent of that
inhaled) is coughed up within 24 hours and is swallowed (reaches the GIT).
The remainder (12.5 percent of that inhaled) resides in the deep lung with a
half-time of 365 days and is then transferred to the blood.
In order to avoid
underestimating radiation doses, we use the insoluble parameters for calculating the transfer to the lung and GIT but use the soluble parameters for the
transfer to all other organs.
On the basis of Figure 3 and the above discussion,
ICRP IT model are
-
the equations for the
Tort * furc 4m * furpur’m + Ym
Ta = furs Am + ferre’ort
.
(34)
Yerr > ‘ert "err
(45)
Vors/dt
You
=
=
Yous
fuporsmm
+
-
Ox
+h
nis?¥pts
furoie’, "pur
4s ryer/{t = fara 7 Og + OL Ye pver
661
(33)
(36)
(37)
(38)