samples were analyzed
for
plutonium, calcium-45, strontium-89, ruthenium-103,
iodine-131, and barium-140.
The I-131 analyses of the pooled urine samples of the
servicemen and Marshallese provided the basis for thyroid dose estimates by Dr. Harris
and Jater researchers.
Dr. Harris judged that 1-131 analysis was the most accurate; it
also led to the highest doses to the servicemen (Reference 9).
The basic finding of the I-131 analysis of the pooled urine sample was the
determination that, for an average individual, the amount of I-131 excreted in urine
over a 24-hour period at the time of the urine sample collection (D+17 days) was 4.0
nanocuries. That resuit is used to determine the amount of I-131 intake.
The amount of a radionuclide excreted in a 24-hour urine sample is related to the
amount of the radionuclide initially intaken (that is, inhaled and/or ingested) by
A(t) =O.°¢€.°
Q°£, YQ) .F F,
(5)
where
A ft) =
the amount (uCi) of the radionuclide in a 24-hour urine sample taken
at time t,
Q) =
the amount (uCi) of the radionuclide intake,
f =
the fractional amount of the radionuclide intake that is transferred
to the blood,
Y(t) =
the ratio of the amount (uCi) of the radionuclide excreted with a 24hour period to the amount (uCi) of the radionuclide uptaken by the
blood, and
Fy =
the fraction of the total daily excretion that is present in the urine,
To apply this equation, not only must the time t of excretion relative to that of intake
be known, but also, for a radionuclide mixture, the time after detonation/release.
18
7b
In