os
to cover multiple categories.

In situations where doses to the bones

appear to be the critical criterion (such as later times after detonation
than considered here), it would be necessary to make a more precise
evaluation.
Unequal distribution of isotopes in the bones has been observed.
Thus, the dotted line in Graph Five is included to suggest a possible
jarger dose to those regions.
Considerable data have been collected on radiation produced bone
cancers.

One summarizing statement that places this in proper perspective

with the other factors discussed above is "--- Visible changes in the
skeleton have been reported only after hundreds of rep were accumulated
and tumars only after 1,500 or more."?

When one examines Graph Five for

relative doses, and reviews the data on doses versus effects to the
gastrointestinal tract and possibly children's thyroids (Table Four), it
would appear that exposure to the bones is not the critical factor for
ingestion of fallout material under emergency conditions, for the first
few weeks after a detonation.

4. Summary

DOE ARCHIVES

Table Four summarizes some possible biological effects fram radiation exposures.

Due to inherent uncertainties in such analyses together

with expected wide biological variances among individuals, Table Four is
intended only to suggest a generalized picture of doses versus effects.
The physical calculations of radiation doses made above were for

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