;
4
The Committee on Pathologic Effects of Atomic Radiation
This Committee was composed of scientists well versed in
radiation pathology and chaired by
Dr. Shields Warren, Direct
of the Cancer Research Institute of the New England Deaconess
Hospital, Boston, Massachusetts, and was for five years~-1948
1952--Director of the Division of Biology and Medicine of the
Atomic Energy Commisston,
This group and subcommittees on blood, lung, delayed
effects,
the
and toxicity of ingested radioactive materials review
present state of knowledge and found that our knowledge o
immediate effects was much greater than for delayed effects,
They observed a five year lessened life span for American
radiologists, estimated to have received from a few roentgens
1000r of exposure as compared with physicians not using
vadiatlon--and agreed that until
we had more precise knowledg
of the cumulative effects of repeated small exposure of the wh
body to radiation the rule of thumb recommended by the Genetic
Committee could equally well apply to medical effects,
That i
no one should receive more than 50r total accumulated dose to
reproductive cells by age 30 - and no more than 50r for each
decade thereafter,
This, they felt, would assure that any lif
expectancy curtailment would be exceedingly minor,
likelihood of induced leukemia minimal,
and the
They noted that as fa
as effects on the blood-forming organs, the intestinal tract,
are concerned, none of these effects have been detected among
who have adhered to present permissible dose levels,
As for the hazards from ingestion and radioactive materi
they confirmed the validity of existing National Committee for
Radiation Protection and International Commission for Radiatio
Protection recommendations and as for the most important of th
~9-
Enclosure II