Because of the strong scientific evidence in support of radiation hormesis, we can no longer ignore this concept. There is, however, need for additional, carefully documented investigations in selected biological systems exposed to LLIR if the matter of radiation hormesis is to be settled once and for all. This need should be addressed without delay, as the matter of benefits derived from LLIR exposure could have major economic and epidemiologic implications. If radiation hormesis becomes firmly established, the requirements for LLIR protection might be relaxed, leading to a sizable cost saving, and the fear of nuclear energy should abate. If this happens, the evergrowing problems associated with energy production from fossil fuels on the one hand and the continued improvements in nuclear reactor technology on the other, will force a world-wide reassessment of risks and benefits associated with nuclear energy. Furthermore, as discussed herein, the major source of exposure from background radiation comes from the inhalation of radon gas. The very high cost associated with effective radon abatement would lead to an abandonment of this mitigation effort so that the limited funds available to improve public health world wide could be used more effectively elsewhere. Thus, we conclude that the time is now to consider eliminating the concept of the radiation paradigm from scientific thinking. We must not continue to unequivocally accept the propositions that 1) all radiation is harmful and 2) that the health effects of LLIR may be directly inferred by scaling down from known deleterious high-dose effects, in as much as there is no scientific basis for an agent not to cause multiple effects.(ABSTRACT TRUNCATED AT 250 WORDS)