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For 1962, our analysis of milk from Pendleton's
39 stations scattered throughout Utah indicated that
for the daily consumption of one liter (1.06 quarts)
of milk, the average yearly iodine 131 intake was
thousand
f/f
Ppicocuries* assuming a three day delay from
milking to consumption.”
This agreed closely with the
thousand
.
f/f
picocuries yearly intake reported by the U.S,
Public Health Service for the salt Lake nilk pool.*
The corresponding infant thyroid doses** were 0.77 or
0.63 rads respectively.
For 1958 and 1957, UsPHS analysis of the Salt Lake
Milk pool indicated average yearly intakes of 11 thousand
and 24 oaocuries of iodine 131 with associated
infant thyroid doses of 0.2 and 1.3 rads
respectively.©
For 1954 and 1952, the beta activity in fallout
collection trays at Salt Lake City was 15 nijlien
disintegrations per minute per square foot at twelve
hours after the detonation of shot "Nancy" on 24
March, 1953 and 23million
disintegrations per minute
per square foot at twelve hours after the detonation of
shot "Easy" on 7 May 1952.
Infant thyroid doses have
been calculated by C.N.1I. as two to twelve rads for
this 1954 shot and three to thirteen rads for this
1952 shot (see pages 529-530, ref.5)}.
A number of
limitations exist in using these values.
First, they
are for only one shot during each year, additional
shots may have caused additional contamination.
Hence
the true
“upper limit" may exceed my so-called "higher
limit."
second,
the ceasurements were tade in Salt Lake
City; not in the pasture lands, pasture contamination
could have been higher or lower.
My presumably less
* A picocurie is 2.22 disintegrations per minute.
** assuming 30% uptake in a 2 grar thyroid with a
subsequent effective retention half-time of 7.6 days,
end the absorption of 6.2 million electron volts of
energy per disintegration of iodine 131i.
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