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SUMMARYAND RECOMMENDATIONS
' In anticipation of the widespread increased
use of nuclear energy, it is time to think anew
aboutradiation protection. We need standards
for the major categories of radiation exposure,
based insofar as possible on risk estimates and
background) and the exposureof anyindividv-
tivity involving radiation with the alternative
options. Such analyses, crude though they
must be at this time, are needed to provide a
better public understanding of the issues and a
sound basis for decision. These analyses should
seek to clarify such matters as: (a) the environ-
version of fissionable materia), (d) avoidance of
on cost-benefit analyses which comparethe ac-
mental and biological risks of given develop-
ments, (b) a comparison of these risks with the
benefits to be gained, (c) the feasibility and
worth of reducing these environmental and
biological risks, (d) the net benefit to societyof
a given development as compared to thealter-
native options.
In the foreseeable future, the major contributors to radiation exposure of the population
will continue to be natural background with an
average whole-body dose of about 100 mrem/
year, and medical applications which nowcontribute comparable exposures to varions tis-
sues of the body. Medica] exposures are not
under control or guidance by regulation or law
at present. The use of ionizing radiation in
medicine is of tremendousvalue butit is essential to reduce exposures since this can be accomplished without loss of benefit and at relatively low cost. The aim is not only to reduce
the radiation exposure to the individual but
also to have procedures carried out with maximum efficiency so that there can be a continuing increase in medical benefits accompanied by
a minimumradiation exposure.
Concern about the nvsiear power industry
arises because of its potential] magnitude and
widespread distribution. Based on experience
to date and present engineering judgment, the
contribution to radiation exposure averaged
over the U. S. population from the developing
nuclear power industry can remain Jess than
about 1 mrem per year (about 1% of natura]
a) kept to a smal! fraction of background provided that there is: (a) attainment and longterm maintenance of anticipated engineering
performance, (b) adequate managementof radioactive wastes, (c) contro] of sabotage and dicatastrophic accidents.
The present Radiation Protection Guide for
the general population was based on genetic
considerations and conforms to the BEAR
Committee recommendations that the average
individual exposure be less than 10 R (Roent-
gens) before the mean age of reproduction (30
years). The FRC did not include medica] radia-
tion in its limits and set 5 rem as the 30-year
limit (0.17 rem per year).
Present estimates of genetic risk are ex-
pressed in four ways: (a) Risk Relative to Natu-
ra] Background Radiation. Exposure to man-
made radiation below the level of background
radiation will produce additional effects that
are less in quantity and no different in kind
from those which man has experienced and has
been able to tolerate throughout his history.
(b) Risk Estimates for Specific Genetic Conditions. The expected effect of radiation can be
compared with current incidence of genetic
effects by use of the concept of doubling dose
(the dose required to produce a number of mu-
tations equal to those which occur naturally).
Based mainly on experimental studies in the
mouse and Drosophila and with some support
from observations of human populations in
Hiroshima and Nagasaki, the doubling dose for
chronic radiation in manis estimated to fal] in
the range of 20-200 rem. It is calculated that
the effect of 170 mrem per year (or 5 rem per
30-year reproduction generation) would cause
in the first generation between 100 and 1800
cases of serious, dominant or X-linked diseases
and defects per year (assuming 3.6 million
births annually in the U.S.). This is an incidence of 0.05%. At equilibrium (approached after several generations) these numbers would
DOE ARCHIVES
5-79 OO. 92-2