36
RESULTS AND DISCUSSION

Barium-133 emits two strong gamma rays, one at
81 keV and one at 360 keV, as well as other less in-

tense gammarays. It was of interest to note that the
shape of the spectrum as recorded by this particular
Nal (Tl) crystal, remained unchanged throughout the
TABLE 10.

Excretion Data

Percent injected dose
Sample

1BBa

Day

Percent injected
dose *Ca

576

A22B

A22C

A22D

A22D

A22B

Feces

1
2
3.
4
5
6
7

—
~~
3.17
1.28
11.16
—
_—

—
—
—
0.439
0.298
0.118
_—

0.386
8.599
7.191
8.708
2.495
2.560
2.666,

0.541
2.289
5.315
10.599
3.552
3.429
1.158

0.883
2.868
6.065
14.174
5.430
11.891)
2.969

0.609
10.060
12.672
12.930
10.067
4,027
2.020

Urine

1
2
3
4
5
6
7

—
—
2.78
0.85
1.06
—
—

—
—
—
0.270
0.877
0.162
—

8.406
3.785
2.742
1.389
1.540;
0.806
1.030

16.374
4.1380;
4.466)
1.842
2.3802]
2,026
0.876

0.816
0.045
0.377
—_
1.781
0.285
0.327

1.110
1.461
0.657
0.624
0.555
0.619
0.284

1
2
3
4
5
6
7

_—

ne
—
—
1.62
0.79
0,72
—

0.046
2.27
2.62
6.27
1.62 |
| 3.18
2.59

0.03
0.55
1.19
5.75
1.54
1.69
1.32

Feces /
urine

14
51)
—_

TABLE 11.

Distal metaphysis

Distal epiphysis
Distal metaphysis plus
distal epiphysis
Tibia
Humerus
Radius
Ulna

Lumbarvertebra
Total femur

an original burden measurement immediately aft:
jection and before any excretion has taken pl:

valid as the 100% point, and the spectrum thu
tamed may be compareddirectly to any later sp:
even though the location of the isotope within th

is not the sameat later times.
Figure 32 indicates that the retention of ***]
these animals is not exactly described by a |]

function.“”) It is clear that the plot of retentio
time does not yield a straight line on log-log co
nates; this is particularly true for the older dogs.
It should be noted that the plasma concentrati
183Ba shown in Figure 32 has been expressed it
same units as the retention. This type of plot s:
the relationship between the specific activity ol
plasma and that of the skeleton.
A straight line can be drawn through the plasma
centration points from day 2 to day 7 or day 14 o1

data from three of the animals. Dog A22D, how:
indicates a definite departure from a straight line

ing this time interval. The values for the interva.
tween 1000 and 1900 days (See Dogs A22B and
indicate that the plasma concentration did not
tinue to fall as rapidly during the entire exposure
riod. The significant point is that by 1000 days :
the isotope administration the plasma specific acti
is a factor of fifty below that of the skeleton. Thes!

of these blood curves on the log-log plot is typicz

156

A22D

A22C

A22B

{1508 days from

(7 days from

(7 days from

(7 days from

0.040
0.025
0.035

0.089
0.043
0.070

0.154
0,155
0.155

0.201
0.150
0.166

_
—
0.103

0.042

0.057

0.066

0.075

0.095
0.075

0.146
0.149

0.212
0.181

_
0.079

0.086
0.152
0.081

0.086
0.086
0.106
0.091

injection)

Mid-shaft

0.55
6.89
19.29
20.72
18.14
6.51
7.11

sorption and scattering of the gammaradiation w
sentially the same after the isotope was dep:
within the bone as it was when the isotope was ©
the blood. Thus, in this ease, the technique of reco

1#Ba ConcENTRATIONS IN Various BoNEsS (PERCENT INJECTED Doss PER GRam ASH)
576

Femur
Proximal epiphysis
Proximal metaphysis
Proximal epiphysis plus
proximal metaphysis

1.08
63.738
16.09
_—
3.05
41.7
9.08

period of observation, namely from minutes to
after injection. This indicates that the effectiv

0.018

injection)

0.026

0.039

0.032
0,030
0.031
0.035

0.047
0.072
0.042
0.044

0.046
0.039

0.033
0.035

0.095
0.068

injection)

0.153

0.070
0.126
0.057
0.069

0.094
0.138

injection)

0.134

0.116
0.152

(3113 days fro
injection)

—

0.052
0.083

gd

Select target paragraph3