The whole body retention at any time t-t of the fraction of initial radioactivity
inputed at time Tt is
Exe a tKi dC t-t)
hu
Thus, the instantaneous activity at time t-T that remains following input during
dt is
0 g-(KEtA)T EyeAtRid (tT) ag
A£,P
1
“1
.
It follows that the instantaneous activity at time t-T that remains following
input during T is
J
T
}
AF Pe
~(Kg+h)T
1
r.X.e
C0 +K3) (t-T)
i*i
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 + 9% is
given by
AP°£) LZixg Ce
~(AtKe)T
Ese
-—(AtK:)T
mye
--(A +K3) @
*
KR, -K&
As previously stated, Eq. (2) appifed 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 initial 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
Mt: