Dr. L? R. Donatdson
Laboratory Of Radiation Biotogy
ACEC
ADVISORY COMMITTEE FOR BIOLOGY AND MEDICINE
TO THE
UNITED STATES ATOMIC ENERGY COMMISSION
|
Dear Mr.
WASHINGTON 23, D.C.
McCone:
Several months ago questions were raised by the Joint Committee on
Atomic Energy concerning the radiation dose to the population of the
United States from the isotopes of short half-lives produced by the
nuclear detonations which had occurred prior to the time of the present
moratorium, Since a complete answer to these questions would require
a most extensive study,
the ACBM recommended in its letter report of
January 14, 1960 to the Chairman that the study be undertaken by the
Division of Biology and Medicine.
Attention was called to the fact
that a substantial amount of analytical data could be found outside
of the AEC and urged that full use be made of all sources of
information and that the capabilities of the Health and Safety
Laboratory be utilized.
The recommended study would necessarily require considerable time.
In the meantime, Dr. Dunham directed the Fallout Studies Branch of
the Division of Biology and Medicine to review the readily available
data in order to arrive at the best possible approximations.
The
report which is forwarded herewith is the result of this undertaking
and, in our opinion, is the most lucid and scientifically firm analysis
of the problem which has as yet been produced,
We concur unanimously
in our comments which follow.
From the study, it is evident that recent analytical data make it
possible to estimate the general radiation dose to the population much
more accurately than heretofore.
For the general population of the
United States living during the decade 1950-1960, it appears that the
average 30-year external whole-body gamma dose from all nuclear testing
conducted to date is probably between 40 and 60 millirads; and that
about one-half of this dose is due to cesium-137; and that about
one-half of the 30-year dose has already been delivered from a mixture
of many shorter lived activities.
The corresponding 70-year dose is
estimated to lie between 45 and 65 millirads.
Persons born after 1960
will necessarily receive substantially less exposure,
From the internally deposited cesium-137 it appears that the whole body
and gonadal dose will lie between 20 and 30 millirads.
It also appears
that the average dose to infant thyroids from iodine-131 during the past
few years has been of the order of a few tenths of a rad, with a small