]
]
Pp=PC7G (DRY) IN
PLANT SAMPLES
5, =PC B/G (DRY) IN
Pr
769
Litt
T
STOMACH CONTENTS —
q
lot
PT TTt
FOOD-CHAIN KINETICS OF RADIONUCLIDES
_1
L titi]
i
|
|
|
107
rT Tt]
|
|
TT Ttttty
Li tii
|
|
Ay=NC 84 (TOTAL) IN
RABBIT THYROIDS
10!
0
5
|
|
1d
15
20
25
DAYS AFTER DETONATION
30
35
Fig. 4—Average concentrations of “I in plant samples, Py, in the
Stomach contents, S,, and in thyroids,A,, of rabbits collected from rep-
resentative locations (see Fig. 2) in the Sedan fallout field at various
times after the detonation.
but the apparent rates of loss, indicating an effective half-life, T,, of
9.0 to 5.5 days, were about the same. The average concentrations of
311 in rabbit thyroids attained a maximum byor before D+ 5 and de-
clined at a half-time rate of 5 to 6 days.
French”’ and French and Van Middlesworth’’ did some experimental
work with jackrabbits near the National Reactor Testing Station in
Idaho. Their reports give estimates of T, ranging from 1.5 to 2.5 days
and of f, ranging from 0.29 + 0.09 to 0.158 + 0.086. A more recent
report by McBride®’ gives estimates of T, = 2.0 days and f, = 0.29. By
trial and error we have found that estimates of T, = 5.0 days and T. =
2.0 days are reasonable approximations in relation to the data given in
Table 2 and Fig. 4. With the use of these parameter values and the ob-
served average values of A,, Eq. 6 was solved for f,. The results based
on plant data, P), indicate f,= 0.18, and the results based on stomach-