Technical Evaluation of the NASA Model
for Cancer Risk to Astronauts
Due to Space Radiation
Committee for Evaluation of Space Radiation Cancer Risk Model
Space Studies Board
Division on Engineering and Physical Sciences
NATIONAL RESEARCH COUNCIL
OF THE NATIONAL ACADEMIES
THE NATIONAL ACADEMIES PRESS
Washington, D.C.
www.nap.edu
THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
Support for this project was provided by Contract NNH10CC48B between the National Academy of Sciences and the National Aeronautics and Space Administration. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the view of the agency that provided support for the project.
International Standard Book Number-13: 978-0-309-25305-5
International Standard Book Number-10: 0-309-25305-5
Copies of this report are available free of charge from:
Space Studies Board
National Research Council
The Keck Center of the National Academies
500 Fifth Street, NW
Washington, DC 20001
Additional copies of this report are available from the National Academies Press, 500 Fifth Street, NW, Keck 360, Washington, DC 20001; (800) 624-6242 or (202) 334-3313; http://www.nap.edu.
Copyright 2012 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America
THE NATIONAL ACADEMIES
Advisers to the Nation on Science, Engineering, and Medicine
The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M. Vest is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Charles M. Vest are chair and vice chair, respectively, of the National Research Council.
OTHER RECENT REPORTS OF THE SPACE STUDIES BOARD
Assessment of Impediments to Interagency Collaboration on Space and Earth Science Missions (Space Studies Board [SSB], 2011)
Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics (Board on Physics and Astronomy [BPA] and SSB, 2011)
Recapturing a Future for Space Exploration: Life and Physical Sciences Research for a New Era (SSB, 2011)
Report of the Panel on Implementing Recommendations from the New Worlds, New Horizons Decadal Survey (BPA and SSB, 2011)
Sharing the Adventure with the Public—The Value and Excitement of “Grand Questions” of Space Science and Exploration: Summary of a Workshop (SSB, 2011)
Vision and Voyages for Planetary Science in the Decade 2013-2022 (SSB, 2011)
Capabilities for the Future: An Assessment of NASA Laboratories for Basic Research (Laboratory Assessments Board with SSB and the Aeronautics and Space Engineering Board [ASEB], 2010)
Controlling Cost Growth of NASA Earth and Space Science Missions (SSB, 2010)
Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies: Final Report (SSB with ASEB, 2010)
An Enabling Foundation for NASA’s Space and Earth Science Missions (SSB, 2010)
Forging the Future of Space Science: The Next 50 Years (SSB, 2010)
Life and Physical Sciences Research for a New Era of Space Exploration: An Interim Report (SSB with ASEB, 2010)
New Worlds, New Horizons in Astronomy and Astrophysics (BPA and SSB, 2010)
Revitalizing NASA’s Suborbital Program: Advancing Science, Driving Innovation, and Developing a Workforce (SSB, 2010)
America’s Future in Space: Aligning the Civil Space Program with National Needs (SSB with ASEB, 2009)
Approaches to Future Space Cooperation and Competition in a Globalizing World: Summary of a Workshop (SSB with ASEB, 2009)
Assessment of Planetary Protection Requirements for Mars Sample Return Missions (SSB, 2009)
Near-Earth Object Surveys and Hazard Mitigation Strategies: Interim Report (SSB with ASEB, 2009)
A Performance Assessment of NASA’s Heliophysics Program (SSB, 2009)
Radioisotope Power Systems: An Imperative for Maintaining U.S. Leadership in Space Exploration (SSB with ASEB, 2009)
Ensuring the Climate Record from the NPOESS and GOES-R Spacecraft: Elements of a Strategy to Recover Measurement Capabilities Lost in Program Restructuring (SSB, 2008)
Launching Science: Science Opportunities Provided by NASA’s Constellation System (SSB with ASEB, 2008)
Opening New Frontiers in Space: Choices for the Next New Frontiers Announcement of Opportunity (SSB, 2008)
Science Opportunities Enabled by NASA’s Constellation System: Interim Report (SSB with ASEB, 2008)
Severe Space Weather Events—Understanding Societal and Economic Impacts: A Workshop Report (SSB, 2008)
Space Science and the International Traffic in Arms Regulations: Summary of a Workshop (SSB, 2008)
Assessment of the NASA Astrobiology Institute (SSB, 2007)
An Astrobiology Strategy for the Exploration of Mars (SSB with the Board on Life Sciences [BLS], 2007)
Building a Better NASA Workforce: Meeting the Workforce Needs for the National Vision for Space Exploration (SSB with ASEB, 2007)
Decadal Science Strategy Surveys: Report of a Workshop (SSB, 2007)
Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond (SSB, 2007)
Exploring Organic Environments in the Solar System (SSB with the Board on Chemical Sciences and Technology, 2007)
Grading NASA’s Solar System Exploration Program: A Midterm Review (SSB, 2007)
The Limits of Organic Life in Planetary Systems (SSB with BLS, 2007)
NASA’s Beyond Einstein Program: An Architecture for Implementation (SSB with BPA, 2007)
Options to Ensure the Climate Record from the NPOESS and GOES-R Spacecraft: A Workshop Report (SSB, 2007)
A Performance Assessment of NASA’s Astrophysics Program (SSB with BPA, 2007)
Portals to the Universe: The NASA Astronomy Science Centers (SSB, 2007)
The Scientific Context for Exploration of the Moon (SSB, 2007)
Limited copies of SSB reports are available free of charge from
Space Studies Board
National Research Council
The Keck Center of the National Academies
500 Fifth Street, N.W., Washington, DC 20001
(202) 334-3477/ssb@nas.edu
www.nationalacademies.org/ssb/ssb.html
COMMITTEE FOR EVALUATION OF SPACE RADIATION CANCER RISK MODEL
R. JULIAN PRESTON, U.S. Environmental Protection Agency, Chair
JOEL S. BEDFORD, Colorado State University
AMY BERRINGTON de GONZALEZ, National Cancer Institute
B. JOHN GARRICK, Garrick Consulting
DUDLEY T. GOODHEAD, Medical Research Council, United Kingdom (Emeritus)
BERNARD A. HARRIS, JR., Vesalius Ventures, Inc.
KATHRYN D. HELD, Massachusetts General Hospital
DAVID G. HOEL, Medical University of South Carolina
JACK R. JOKIPII, University of Arizona, Lunar and Planetary Laboratory
INSOO JUN, Jet Propulsion Laboratory, California Institute of Technology
CHARLES E. LAND, National Cancer Institute (retired)
HANS-GEORG MENZEL, CERN (retired)
PETER O’NEILL, University of Oxford
Staff
SANDRA J. GRAHAM, Senior Program Officer, Study Director
CATHERINE A. GRUBER, Editor
AMANDA R. THIBAULT, Research Associate
RODNEY HOWARD, Senior Program Assistant
MICHAEL H. MOLONEY, Director, Space Studies Board
SPACE STUDIES BOARD
CHARLES F. KENNEL, Scripps Institution of Oceanography, University of California, San Diego, Chair
JOHN KLINEBERG, Space Systems/Loral (retired), Vice Chair
MARK R. ABBOTT, Oregon State University
STEVEN J. BATTEL, Battel Engineering
YVONNE C. BRILL, Aerospace Consultant
ELIZABETH R. CANTWELL, Oak Ridge National Laboratory
ANDREW B. CHRISTENSEN, Dixie State College and Aerospace Corporation
ALAN DRESSLER, Observatories of the Carnegie Institution
JACK D. FELLOWS, University Corporation for Atmospheric Research
HEIDI B. HAMMEL, Space Science Institute
FIONA A. HARRISON, California Institute of Technology
ANTHONY C. JANETOS, University of Maryland
JOAN JOHNSON-FREESE, Naval War College
ROBERT P. LIN, University of California, Berkeley
MOLLY K. MACAULEY, Resources for the Future
JOHN F. MUSTARD, Brown University
ROBERT T. PAPPALARDO, Jet Propulsion Laboratory, California Institute of Technology
JAMES PAWELCZYK, Pennsylvania State University
MARCIA J. RIEKE, University of Arizona
DAVID N. SPERGEL, Princeton University
WARREN M. WASHINGTON, National Center for Atmospheric Research
CLIFFORD M. WILL, Washington University
THOMAS H. ZURBUCHEN, University of Michigan
MICHAEL H. MOLONEY, Director
CARMELA J. CHAMBERLAIN, Administrative Coordinator
TANJA PILZAK, Manager, Program Operations
CELESTE A. NAYLOR, Information Management Associate
CHRISTINA O. SHIPMAN, Financial Officer
SANDRA WILSON, Financial Assistant
Acknowledgment of Reviewers
This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the Report Review Committee of the National Research Council (NRC). The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:
Sally A. Amundson, Columbia University Medical Center,
John D. Boice, Jr., International Epidemiology Institute Ltd.,
Leslie A. Braby, Texas A&M University,
James E. Cleaver, University of California, San Francisco,
Howard D. Ozer, University of Illinois Cancer Center,
Jonathan M. Samet, University of Southern California, and
Ronald E. Turner, Analytic Services, Inc. (ANSER).
Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by John R. Ball, American Society for Clinical Pathology (retired). Appointed by the NRC, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.
This page intentionally left blank.
Contents
General Cancer Risk Estimation Approach
Approach to the Committee’s Evaluation
Space Radiation Environments and Transport Models
Cancer Mortality Risk Estimation
Transfer from the Japanese to the U.S. Population
Dose and Dose Rate Effectiveness Factor
Uncertainties in Low Linear Energy Transfer Risk Model
Epidemiological Basis for Radiation-Related Cancer Risk Estimation
Dependence on Atomic Bomb Survivor Data
Cancer Risks and Radiation Quality in the Model
Quality Factors for Leukemia and Solid Cancers
Replacement of LET-Based Quality Factors with Track Structure-Based Quality Factors
Risk Cross Sections and Quality Factors
Non-Targeted Effects in the NASA Model
Qualitative Differences Between Low-LET Radiation and Heavy-Ion Biological Effects
Data or Research That Could Improve This Portion of NASA’s Proposed Model
Integration and Completeness of the Model
Model Completeness, Improvements, and Recommendations