wh eb att n SUMMARY AND RECOMMENDATIONS In anticipation of the widespread increased use of nuclear energy, it is time to think anew about radiation protection. We need standards background) and the exposure of any individual kept to a small fraction of background pro- based insofar as possible on risk estimates and on cost-benefit analyses which compare the activity involving radiation with the alternative options. Such analyses, crude though they performance, (b) adequate management of radioactive wastes, (c) contro] of sabotage and di- vided that there jis: (a) attainment and Jong- for the major categories of radiation exposure, term maintenance of anticipated engineering must be at this time, are needed to provide a version of fissionable materia}, (@) avoidance of catastrophic accidents. The present Radiation Protection Guide for the genera] population was based on genetic considerations and conforms to the BEAR better public understanding of the issues and a sound basis for decision. These analyses should seek to clarify such matters as: (a) the environmental] and biological! risks of given developments, (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 the alternative 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 exposiires to various tissues of the body. Medical exposures are not under control or guidance by regulation or law at present. The use of ionizing radiation in medicine is of tremendous value but it 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 maxi- mumefficiency so that there can be a continu- ing increase in medical benefits accompanied by & minimumradiation exposure. Concern about the neciear power industry arises because of its potertial magnitude and widespread distribution. Based on experience ta date and present engineering judgment, the contribution to radiation exposure averaged over the U. S. population from the developing nuclear pawer industry can remain less than about 1 mrem per year (about 1% of natural 405-195 O- 12-2 9013ib9 Committee recommendations that the average . individual exposure be less than 10 R (Roentgens} before the mean age of reproduction (30 years). The FRC did not include medical radiation in its limits and set 5 rem as the 30-year limit (0.17 rem per vear). Present estimates of genetic risk are expressed in four ways: (a) Risk Relative to Natural Background Radiation. Exposure to manmade radiation belowthe 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. (ob) 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 mutations equal to those which occur natura}ly). 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 man is estimated to fall] 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 |