The whole body retention at any time t-t of the fraction of initial radioactivity
inputed at time t is
E.x.eca tki Cet)
vi
Thus, the instantaneous activity at time t-T that remains following input during
hy
dt is
AEP o e
-(Kgta)t Bixee Et dt.
It follows that the instantaneous activity at time t-T that remains following
input during T is
J
T
°
Af Pee
-(Kpth )t
L.x.e
“i
-O+Kz) (t—1)
dt.
The solution of the integral yields a general expression that depends on
the user defining t.
For example, if t is the fixed uptake interval, T, plus an
additional fixed post uptake interval, @, then the body burden at T + @ is
given by
AP°£) Lixy Ce
~(\+Kg)T
-e
“4KDT) o OAtKi) g
.
K,~ K.
As previously stated, Eq. (2) applied at Rongelap and Utirik, it was
for the situation that variable time t was the uptake interval.
Additionally,
persons who returned to the atolls in June 1954 and June 1957 did so with an ini-~
tial body burden, q°.
The behavior of this contribution to body burden,
q, was embodied in the q° term of Eq. (2).
A similar model was used to relate