C.W. Mays - Page ll
Low-dose children should be those whose infant years
occurred after these times (or long before), plus those
who drank powdered milk or uncontaminated fresh milk
during these incidents.
If non-radiation factors predispose the children
of this region to a high incidence of thyroid
abnormalities,
these abnormalities should occur
throughout the dose categories.
However, if the incidence is significantly greater
in the higher-dose groups, radiation would be implicated
as a causative factor.
In a study of this nature it is
extremely important tc have low-dose subjects from the
same region and culture to serve as controls.
In the thirteen years which have elapsed since the
incident of 1953, perhaps half of the total cumulative
radiation-induced cancers should have appeared among
the St. George children; or one - four cases under
assumption (A), 0.1-0.4 cases under assumption (B), and
no cases under assumption (C).
The fact that no thyroid
cancers have yet been observed* in these chilaren?*
suggests that assumption (A) overestimates the true
effect and therefore constitutes an upper limit.
Establishment of an upper limit is of real value, but
establishment of the true dose-response relationship
would be of even greater importance.
true dose-response relationship,
expanded.
To establish the
the study needs to be
Note that under assumption (B), less than one
radiation-induced cancer is predicted to have occurred
before now (1966) among the St.George children.
2) For the entire state of Utah,
the estimated number
of radiation-induced cancers is five ~ ten times larger
than for the limited st.
George area,
assuming a linear
dose~response relationship (compare Tables 3 and 4).
* The children who moved from this area before the
recent survey have not been examined,
DOE ARCHIVES
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