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10 August 1963
ESTIMATED THYROID IRRADIATION OF UTAH INFANTS
_
DUE TO NUCLEAR TESTS IN NEVADA
MOEA OS.
Charles W. Mays
U. of Utah, Salt Lake City, Utah
ABSTRACT: Assay of milk for fallout 1131 from Nevada tests
during 1962 indiceted an average thyroid dose of about
1.0 rad to the 53,000 Utah infants under 2 years old.
Unfortunately, 113. had not been measured in milk or
people during earlier testing. However, thyroid doses
from the earlier tests can be estimated crudely using
air beta concentrations and published yields of announ-
ced detonations.
The number of exposed Utah infants
and their estimated average thyroid doses are listed
for each year of Nevada testing:
YEAR
1951
1952
1953%
1955
1957
1958
1962
INFANTS UNDER 2 YR.
40,000
41,000
43 ,000
45,009
47 ,09C
48 ,00C
53,000
*St. George
ESTIMATED DOSE (RAD)
0.4
3.8
6.3
2.0
8.6
1.4
1.0
700
68
Using unverified assumptions, 0-22 thyroid cancers
from Nevada I131 fallout are predicted for Utah children,
Despite uncertainties in these estimates, they indicate
that studies for possible delayed effects of radiation
should be considered for Utah.
METHODS Of ESTIMATING THYROID EXPOSURE
The problem of estimating thvroid doses from I
never measured is very difficult.
need to obtain the infor;nation.
131
when the I
131
was
This difficulty does not decrease the
Methods for estimating yt dose will be
discussed in detail, both to indicate how my estimates were made, and to
point out how these estimates could be improved with additional data.
the I
131
dose from Nevada testing is considered:
the total dose is
Only