acceptable method for making decisions related to crew health and safety. The tacit assumption that risk values and associated medical decision making can be extrapolated from current data obtained from limited sources, such as anecdotal reports from previous crew members and short-duration animal and human studies in the actual space environment, raises concerns.

Recommendation: NASA should critically analyze both disaggregated and aggregated data (such as that in the Longitudinal Study of Astronaut Health and the Life Sciences Data Archive) to derive confidence bands for medical risks. The quality of the data and the difference between best-case and worst-case scenarios should be assessed and analyzed.

  • Additional, hypothesis-driven, long-duration research on the ISS may be necessary to refine confidence bands such that there is a reasonable statistical likelihood that the adaptation of crew members during a long-duration mission will fall within a clinically acceptable range.

  • Research into predictors of individual responses to conditions on the ISS or during extended-duration spaceflight is needed to allow tailoring of individual countermeasures.

Recommendation: NASA should utilize previous recommendations (e.g., those of the IOM and NRC bioastronautics roadmap review committee) to select and sequence additional needed experiments and address in a timely fashion those critical issues that could affect important decisions on the design of architecture for future missions.


1. National Research Council (NRC). 1987. A Strategy for Space Biology and Medical Science. National Academy Press, Washington, D.C.

2. NRC. 1998. A Strategy for Research in Space Biology and Medicine in the New Century. National Academy Press, Washington, D.C.

3. Institute of Medicine (IOM). 2001. Safe Passage: Astronaut Care for Exploration Missions. National Academy Press, Washington, D.C., p. 3.

4. IOM and NRC. 2006. A Risk Reduction Strategy for Human Exploration of Space: A Review of NASA’s Bioastronautics Roadmap. The National Academies Press, Washington, D.C.

5. Brenner, D.J., and E.J. Hall. 1992. Commentary 2 on Cox and Little: Radiation-induced oncogenic transformation: The interplay between dose, dose protraction, and radiation quality. Adv. Radiat. Biol. 16: 167-179.

6. Curtis, S.B. 1994. Importance of dose rate and cell proliferation in the evaluation of biological experimental results. Adv. Space Res. 14: 989-996.

7. Curtis, S.B. 1996. Possible effects of protracted exposure to the additivity risks from space radiations. Adv. Space Res. 18: 41-44.

8. Withers, H.R., L.J. Peters, and H.S. Kogelnik. 1980. The pathobiology of late effects in irradiation. Pp. 439-448 in Radiation Biology in Cancer Research (R.E. Meyn and H.R. Withers, eds.). Raven Press, New York, N.Y.

9. Rubin, P., and G.W. Casarett. 1968. Clinical radiation pathology as applied to curative radiotherapy. Cancer 22: 767-778.

10. Denham, J.W., and M. Hauer-Jensen. 2002. The radiotherapeutic injuryA complex “wound.” Radiother. Oncol. 63: 129-145.

11. Coleman, C.N., H.B. Stone, J.E. Moulder, and T.C. Pellmar. 2004. Modulation of radiation injury. Science 304: 693-694.

12. Stone, H.B., C.N. Coleman, M.S. Anscher, and W.H. McBride. 2003. Effects of radiation on normal tissue: Consequences and mechanisms. Lancet Oncol. 4: 529-536.

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement