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On the Continued Operation of the BEVALAC Facility (1992)--Attachment 2 On the Continued Operation of the BEVALAC Facility Attachment 2 Excerpts and Recommendations Concerning Biological Effects of Radiation Exposure It is critical for NASA to formalize agreements to utilize one or more of the federal accelerator facilities, and to assure that those facilities remain in operation until necessary ground-based research is completed. —Aerospace Medicine Advisory Committee/NASA Advisory Council, Strategic Considerations for Support of Humans in Space and Moon-Mars Exploration Missions, Life Sciences Research and Technology Programs. 1992 In order to protect crews, to the extent possible, from the various harmful effects of radiation, it is necessary to thoroughly characterize the radiation environment, LETTER understand the biological effects of HZE radiation and protons (leading to the ATTACHMENT 1 establishment of appropriate risk levels and limits for radiation exposure), and ATTACHMENT 2 ATTACHMENT 3 accurately predict and provide warning of any increased levels of radiation. —Discipline Working Group on Radiation Health and Environmental Health, NASA, Space Radiation Health Program Plan. 1991 Determining the long-term medical consequences of exposure to high Z element (HZE) particles present as a component of galactic cosmic radiation (GCR) is critical. The biological hazards associated with HZE particles, i.e., the "late effects," are not adequately known and may pose unacceptable long-term cancer risks. Exposure can result in life-threatening and life-shortening effects, such as cancer, and other detrimental consequences including cataract formation, mutagenesis, and other tissue damage. —Aerospace Medicine Advisory Committee/NASA Advisory Council, Strategic Considerations for Support of Humans in Space and Moon-Mars Exploration Missions, Life Sciences Research file:///C|/SSB_old_web/bevalac92a2.htm (1 of 5) [6/18/2004 10:58:07 AM]

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On the Continued Operation of the BEVALAC Facility (1992)--Attachment 2 and Technology Programs. 1992 NASA should make a commitment to support fundamental research on the biological effects of radiation. This support and commitment should take the form of expanding NASA's role in and funding for basic research and of contributing to the necessary facilities, such as the BEVALAC accelerator. —Life Sciences Strategic Planning Committee, NASA, Exploring the Living Universe—A Strategy for Space Life Sciences. 1988 In summary, the highest priorities are for improved dosimetry and for studies of the effects of HZE particles so that the risks of both stochastic effects, such as carcinogenesis, and nonstochastic effects such as CNS damage, can be estimated with confidence. National Council on Radiation Protection and Measurements, Guidance on Radiation Received in Space Activities. 1989 One concern requiring further study in this area is the high-energy high-charge component of the cosmic ray flux, which can damage non-dividing cells, including those of the central nervous system. National Commission on Space, Pioneering the Space Frontier. 1986 The Space Exploration Initiative requires understanding and management of space radiation hazards. Uncertainties in these radiation effects on cells, tissue and small organisms could be reduced by simulations using the Bevalac at the Berkeley Radiation Laboratory. Synthesis Group, NASA, America at the Threshold. 1991 REPORTS FROM THE NATIONAL RESEARCH COUNCIL The availability of HZE particles for experimental radiation biology is extremely limited. The only feasible approach to obtaining the required information is to carry out controlled studies in adequate ground-based facilities. Radiobiological Advisory Panel/Space Science Board, Radiobiological Factors in Manned Space Flight. 1967 file:///C|/SSB_old_web/bevalac92a2.htm (2 of 5) [6/18/2004 10:58:07 AM]

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On the Continued Operation of the BEVALAC Facility (1992)--Attachment 2 The availability of a ground-based accelerator capable of producing HZE particles now permits the design of precisely ordered experiments. Such experiments should be supported. Committee on Space Biology and Medicine/Space Science Board, A Strategy for Space Biology and Medical Science for the 1980's and 1990's. 1987 It is important to learn more about the relative biological effects of radiation influences, particularly high-Z galactic cosmic rays and solar flare electrons and their relationship to cancer and cataract induction in order to set meaningful guidelines for radiation protection. The question of appropriate shielding in flight is complex and requires further study. Committee on Human Exploration of Space/National Research Council, Human Exploration of Space—A Review of NASA's 90- Day Study and Alternatives. 1990 Terrestrial studies of the biological effects of low-level, high LET irradiation on cell cultures and animals (using particle accelerators) should be expanded, with particular attention paid to the space radiation problem. Life Sciences Task Group, Space Studies Board, Space Science in the Twenty-First Century—Imperatives for the Decades 1995 to 2015—Overview and Life Sciences. 1988 Planning for extended human sojourns in space mandates that we have quantitative knowledge about the dose rates and the types of radiation that will be encountered. Similarly, the effects of the different types of radiation encountered in space, especially deep space, must be defined quantitatively. Much of the necessary radiobiology research can be carried out on Earth with defined radiation sources. Committee on Space Biology and Medicine/Space Studies Board, Assessment of Programs in Space Biology and Medicine—1991. 1991 One way to maximize the return on investment in research is through various modes of cooperative research, with foreign partners, private concerns, and between federal agencies. . . . [An] example for . . . collaboration between federal agencies are facilities supported by the Department of Energy such as the BEVALAC, which has the capability of providing for study of very high-Z particles and their biological effects. file:///C|/SSB_old_web/bevalac92a2.htm (3 of 5) [6/18/2004 10:58:07 AM]

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On the Continued Operation of the BEVALAC Facility (1992)--Attachment 2 Space Studies Board, Priorities in Space Life Sciences Research, testimony by Space Studies Board Member Robert H. Moser to the House Budget Committee Task Force on Defense, Foreign Policy and Space, April 28, 1992 Improved measurements of cross-sections and better modeling of heavy-ion interactions, particularly for the yield and spectra of neutrons and other secondary particles generated in the shielding material, are also required. NASA currently helps support the BEVALAC heavy-ion accelerator and some cross- section studies. However, the BEVALAC has been threatened with closure, thus endangering some of the enabling research on both cross-section measurements and the long-term biological effects of ionizing radiation. Committee on Human Exploration/Space Studies Board, Scientific Prerequisites for the Human Exploration of Space. 1993, in press Letter Attachment 1—Letter from DOE Attachment 3—Selected Reports Concerning Radiation Research and Humans in Space file:///C|/SSB_old_web/bevalac92a2.htm (4 of 5) [6/18/2004 10:58:07 AM]