to cover multiple categories. In situations where doses to the bones appear to be the critical criterion (such as later times after detonation * than consideredhere), 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 suggested a possible larger dose to those regions. Considerable data have been collected on radiation producedbone 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 tumors only after 1,500 or more." 29 When one examires Graph Five for relative doses, and reviews the data on doses versus effects to the gas- trointestinal 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. h. Summary of Biological Effects Table Four summarizes some possible biologit¢al effects fran 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 - 1; DOE ARCHIVES