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NIRS/PC Prefiled Exhibit 225Docketed 09/23/20053*)**3SIIb**Health Risks From Exposure toLow Levels of-Ionizing RadiationBEIRVII-Phase2Committee to Assess Health Risks from Exposure to Low Levels of Ionizing RadiationBoard on Radiation Effects ResearchDivision on Earth and Life StudiesNATIONAL RESEARCH COUNCILOF THE NAIONAL ACADEMIESTHE NATIONAL ACADEMIES PRESSWashington, D.C.www.nap.edu
IL:ENOTICE: The project that is the subject of this report was approved by the Governing Boardof the National Research Council, whose members are drawn from the councils of-theNational Academy of Sciences, the National Academy of Engineering, and the Institute ofMedicine. The members of the committee responsible for the report were chosen for theirspecial competences and with regard for appropriate balance.This study was supported by EPA: Grant #X-826842-01 and NRC Grant # NRC-04-98061. Any opinions, findings, conclusions, or recommendations expressed in thispublication are those of the author(s) and do not necessarily reflect the views of theorganizations or agencies that provided support for the project.International Standard Book NumberInternational Standard Book NumberLibrary of Congress Control Number(Book)(PDF)Additional copies of this report are available from the National Academies Press, 500 Fifth Street,N.W., Lockbox 285, Washington, DC 20055; (800) 624-6242 or (202) 334-3313 (in theWashington metropolitan area); Internet, http://wvww.nap.edu.Copyright 2005 by the National Academy of Sciences. All rights reserved.Printed in the United States of America.K)
THE NATIONAL ACADEMIESAdvisers to the Nation on Science, Engineering, dndMedicineThe National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguishedscholars engaged in scientific and engineering research, dedicated to the furtherance of science andtechnology and to their use for the general welfare. Upon the authority of the charter granted to it by theCongress in 1863, the Academy has a mandate that requires it to advise, the federal government'onscientific 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 NationalAcademy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in itsadmninistration and in the selection of its members, sharing with the National Academy of Sciences theresponsibility for advising the federal govirnrment. The National'Academy of Engineering also sponsorsengineering programs aimed at meeting national needs, encourages education and research, and recognizesthe superior achievements of engineers. Dr. Win. A. Wulf is president of the National Academy ofEngineering.The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure theservices of eminent members of appropriate professions in the examination of policy matters pertaining tothe health of the public. The Institute acts under the responsibility given to the National'Academy ofSciences by its congressional charter to be an adviser to the federal government and, upon its owninitiative, to identify issues of medical care, research, and education.' Dr. Harvey V. Fineberg is presidentof the Institute of Medicine.,The National Research Council was organized by the National Academy of Sciences in 1916 to associatethe broad community of science and technology with the Academy's purposes of furthering knowledge andadvising the' federal government. Functioning 'in accordance with general policies determined by theAcademy, the Council has become the principal operating agency of both the National Academy ofSciences 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 Academiesand the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Wm. A. Wulf are chair and vice chair,respectively, of the National Research Council.www.national-academles.org.,.
-.ICOMMITTEE TO ASSESS HEALTH RISKS FROM EXPOSURE TO LOWLEVELS OF IONIZING RADIATIONRICHARD R MONSON (Chairman), Harvard School of Public Health,Boston, MAJAMES E. CLEAVER, (Vice Chairman), University of California, San Francisco, CAHERBERT L. ABRAMS, Stanford University, Stanford, CAEULA BINGHA.M, University of Cincinnati, Cincinnati, OHPATRICIA A. BUFFLER, University of California, Berkeley, CAELISABETH CARDIS, International Agency for Research on Cancer, Lyon, FranceROGER COX, National Radiological Protection Board, United KingdomSCOTT DAVIS, University of Washington and Fred Hutchinson Cancer ResearchCenter, Seattle, WAWILLIAM C. DEWEY, University of California, San Francisco, San Francisco,CAETHEL S. GILBERT, National Cancer Institute, Rockville, MDALBRECIIT M. KELLERER, Ludwig-Maximilians-Universitat, Mflnchen, GermanyDANIEL KREWSKI, University of Ottawa, Ottawa, Ontario, CanadaTOMAS R. LINDAHL, Cancer Research UK London Research Institute, UnitedKingdomKATHERINE E. ROWAN, George Mason University, Fairfax, VAK SANKARANARAYANAN, Leiden University Medical Centre, Leiden, TheNetherlandsDANIEL W. SCHAFER, Oregon State University, Corvallis, OR (from May 2002)LEONARD A. STEFANSKI, North Carolina State University, Raleigh, NC (throughMay 2002)ROBERT L. ULLRICII, Colorado State University, Fort Collins, COCONSULTANTSJOHN D. BOICE, Jr., International Epidemiology Institute, Rockville, MDKIYOHIKO MIABUCHI, National Cancer Institute, Rockville, MDNATIONAL RESEARCH COUNCIL STAFFRICK JOSTES, Study DirectorEVAN B. DOUPLE, BRER DirectorDONALD A. PIERCE, Research Advisor RERFCOURTNEY GIBBS, Program AssistantDORIS E. TAYLOR, Staff AssistantCATIIIE BERKLEY, Financial OfficerNATIONAL ACADEMY PRESS, Editorivit-
BOARD ON RADIATION EFFECTS RESEARCHS. JAMES ADELSTEIN (Chairman),Harvard Medical School, Boston, MAHAROLD L. BECK, Department of Energy Environmental Laboratory (Retired), NewYork, NYJOEL S. BEDFORD, Colorado State University, Fort Collins, COJAMES E. CLEAVER, University of California San Francisco Cancer Center, SanFrancisco, CASARAH S. DARBY, University of Oxford, United KingdomSHARON L. DUNNWOODY, University of Wisconsin, Madison, WIC. CLIFTON LING, Memorial Sloan-Kettering Cancer Center, New York, NYDANIEL KREWSKI, University of Ottawa, Ottawa, CanadaTHEODORE L. PHILLIPS, University of California, San Francisco, CAANDREW\' M. SESSLER, E.O. Lawrence Berkeley National Laboratory, Berkeley, CANational Laboratory, Berkeley, CAJOHN C. VILLFORTH, Food and Drug Law Institute (Retired), Derwood, MDPAUL L. ZEIMER, Purdue University, West Lafayette, INNATIONAL RESEARCH COUNCIL STAFFEVAN B. DOUPLE, Director, Board on Radiation Effects ResearchISAF AL-NABULSI, Senior Program OfficerRICKJOSTES, Senior Program OfficerCATHERINE S. BERKLEY, Administrative AssociateCOURTNEY GIBBS, Program AssistantDORIS TAYLOR, Staff Assistantv
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Preface:BACKGROUND'This is the seventh in a series of reports from the Nation'al Research Councilprepared to advise the U.S. government on the relationship between exposure to ionizingradiation and human health. In 1996 the National Academies (NAS) was requested bythe U. S. Environmental Protection 'Agency to initiate a scoping study preparatory to anew review of the health risks from exposure tallow levels of ionizing radiations. Themain purpose of.the new' review would be to update the Biological Effects of lIonizingRadiation V (BEIR V) report (NRC 1990), using newi information from epidemiologicand experimental res6arch that has accumulated during the 10 years -since the 1990review. Analysis of thos6 data would help to determine how regulatory bodies-shouldbest characterize risks at the doses and dose rates experienced by radiation workers andmembers of the general public. BEIR-VII-phase 1 was the preliminary 'survey t6 evaluatewhether it' was'appropnate and feasible to conduct a BEIR VII-phase 2 study. The phaseI 'study determined that it was 'appropriate and feasible to proceed to a phase 2 study.The phase 1 study, Health Effects of Exposure to Low Levels of Ionizing Radiations:Time for Reassessment?, published in 1998,' also provided the basis for the phase 2Statement of Task that follows:BEIR VII PHASE 2 STATEMENT OF TASK'.The primary objective of the study is to develop the best possible risk estimate forexposure to low-dose, low-linear energy transfer (LET) radiation in human subjects. Inorder to do this,-the committee will 1) conduct a comprehensive review of all relevantepidemiologic data related to the risk from exposure to low-dose, low-LET radiation; '2)define and establish principles on which quantitative analyses of low-dose and low doserate effects can be 'based, including requirements for epidemiologic data and cohortcharacteristics; 3) consider relevant biologic factors (such as the'.dose- and dose-rateeffectiveness factor, relativerbiologic effectiveness, genomic 'instability, and adaptiveresponses) and appropriate methods to develop etiologic models (favoring simple asopposed to complex models) and estimate population detriment; 4) assess the currentstatus and' relevance to risk, models of biologic data and models of 'careinogenesis,including critical assessment of all data that might affect the shape of the response curveat low doses, in* particular, evidence' for: or, against thresholds in dose-responserelationships and evidence for or against adaptive responses and radiation hormesis;.5)consider when -appropriate.potential target cells and problems that might exist indetermining dose to the target cell; and 6) consider any recent evidence regarding geneticeffects not related to cancer.' JIn, performing -the above 'tasks, the committee shouldconsider all relevant data, even if obtained from high radiation exposures 'or at high doserates.-.-With respect to modeling, the committee will 1) develop appropriate risk modelsfor all cancer sites and other outcomes for which there is adequate data to support aquantitative:' estimate of risk,' including benign disease and genetic-effects;.2)'provideexamples of specific risk calculations based onwthe models and explain the appropriateuse of the risk models; 3) describe and define the limitations and uncertainties of the risk'vii
models and their results; 4) discuss the role and effect of modifying factors, includinghost (such as individual susceptibility and variability, age, and sex), environment (such asaltitude and UV), and lifestyle (such as smoking history and alcohol consumption)factors; and 5) identify critical gaps in knowledge that should be filled by future research.WHAT HAS CHANGED SINCE THE LAST BEIR REPORT ON THE HEALTHEFFECTS OF LOW LEVELS OF LOW-LET IONIZING RADIATIONIn the 15 years since the publication of the. previous BEIR report on Low LETradiation (BEIR V) much new information has become available on the health effects ofionizing radiation. . Since the 1990 BEIR V report, substantial new information onradiation-induced., cancer has. become available from the Hiroshima and Naigasakisurvivors, slightly less than half of whom were alive in 2000.:! Of special importance is.the cancer incidence data, from the Hiroshima"'and' Nagasaki tumor registries. Thecommittee evaluated nearly 13,000 incidence cancers and approximately 10,000 cancerdeaths in contrast to fewer than 6000 cancer deaths available to the BEIR V committee.Also, since completion ofthe 1990 report, additional evidence has emerged from studiesof the Hiroshima and Nagasaki bomb survivors suggesting that other health effects, suchas cardiovascular disease and stroke, can result from radiation exposure.A major reevaluation of the dosimetry at Hiroshima and Nagasaki has recentlybeen completed that lends more certainty to dose estimates and provides increasedconfidence in the relationship between radiation exposure and health effects observed inthe Japanese A-bomb survivors. Additional new information is also available fromradiation-worker studies, medical-radiation exposures, and populations withenvironmental exposures.Although the cancer risk estimates have not changed greatly since the 1990report, confidence in the estimates has risen because of the increase in epidemiologic andbiological data available to the committee.Progress has also been made since the 1990 report in areas of science that relate tothe estimation of genetic (hereditary) effects of radiation. In particular (a) advances inhuman molecular. biology have been incorporated into the conceptual framework ofgenetic risk estimation and (b) it has become possible to project risks for 'all classes ofgenetic diseases, i.e., those'with more complex as well as simple patterns of inheritance.Advances in cell and molecular biology have also contributed new information onthe mechanisms. through which cells respond to radiation-induced damage and to theclose associations between DNA damage response and cancer development.ORGANIZATION OF THIE STUDYThe National Research Council appointed a committee comprised of scientistsand educators. Some had particular expertise in conducting research on ionizingradiation, while others were experienced in. fields relevant to the Committee's charge.The NRC vetted'all potential members to assure that each was free from any apparent orpotential conflict of interest. The work of the committee was conducted with theassistance of the Board of Radiation Effects Research (BRER) of the Division on Earthand Life Sciences.viii)
The Committee held 11 meetings over a period of 4.5 years. The long timeduration of the Committee was largely due to a period of reduced activity while awaitingcompletion of the update of the dosimetry and exposure estimates to atomic bombsurvivors of Hiroshima and Nagasaki, Japan (the so-called DS-02: Dosimetry System,2002).Six of the meetings included participation from the public for a portion of themeeting, and five of the meetings were conducted exclusively in executive session. Eachmeeting included extensive deliberations involving the Committee as a whole; inaddition, two major subcommittees were formed that were termed "biology" and"epidemiology". Dr. Monson convened the epidemiology sessions and Dr. Cleaverconvened the biology sessions. Also, a number of loosely organized and non-permanentworking groups were formed to discuss the many issues before the Committee. Thisenabled biologists and non-biologists to work together and to evaluate each other's work.ORGANIZATION OF TIlE REPORTAs noted under our STATEMENT OF TASK, our focus was to develop the bestpossible risk estimate for exposure to low-dose, low-LET radiation in human subjects.Accordingly, chapters 1-4 discuss basic aspects of radiation physics and radiationbiology, including the known interaction between radiation exposure and geneticmaterial, cellular structures, and whole organisms. Chapters 5-9 discuss basic principlesof epidemiology as well as substantive data relating to exposure from the atomic bombs,medical radiation, occupational radiation, and environmental radiation. Chapters 10-12,to the extent possible, integrate the information from biology and epidemiology anddevelop risk estimates based on this information. Three summary sections providedifferent levels of description of the report. Chapter 13 is an overall scientific summaryand lays out the Research Needs that the Committee has identified. The ExecutiveSummary is an abbreviated and reorganized version of Chapter 13 that provides anoverview of the report. The Public Summary addresses the findings of the Committee aswell as how the report is relevant to public concerns about exposure to ionizing radiation.ix
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REVIEWERSThis report has been reviewed in draft form by persons chosen for their. diverseperspectives and technical expertise in accordance with procedures approved by theNational Research Council's Report Review Committee. The purposes of this review areto provide candid and critical comments that will assist the institution in making thepublished report as sound as possible and to ensure that the report meets institutionalstandards of objectivity, evidence, and responsiveness to the study charge. The reviewcomments and draft manuscript remain confidential to protect the integrity. of thedeliberative process. We wish to thank the following for their participation in the reviewof this report:Seymour'Abrahamson, University of Wisconsin, Madison, WIJohn F. Aheame, Sigma Xi, The Scientific Research Society, Research Triangle Park,-NC'Allan Balmain, University of Califomia, San Francisco, CAMichael Cornforth, University of Texas, Galvaston, TX'James F. Crow, University of Wisconsin, Madison, WIRichard D. Hichwa, University of Iowa, Iowa City, IAJohn Easton, University of Chicago Hospitals, Chicago, ILEric J. Hall, Columbia University College of Physicians and Surgeons, New York, NYHedvig Hricak, Memorial Sloan-Kettering Cancer Center, New York, NYGlenn F. Knoll, University of Michigan, Ann Arbor, MIJack S. Mandel, Emory University Rollins School of Public Health, Atlanta, GAJohn P. Murnane, University of California, San Francisco, CAHooshang Nikjoo, National Aeronautics and Space Administration, Houston, TXJonathan M. Samet, Johns Hopkins University, Baltimore, MDSusan S. Wallace, University of Vermont, Burlington, VTChris G. Whipple, ENVIRON International Corporation, Emeryville, CAJ''Although the reviewers listed above have provided many constructive commentsand suggestions, they' were not asked to endorse the conclusions or recommendations, nordid they see the final draft of the report before its release. The review of this report wasoverseen by George M. Homberger, Ernest H. Ern Professor of Environmental Sciences& Associate Dean for the Sciences, University of Virginia, and John C. Bailer, III,Professor Emeritus, University of Chicago. Appointed by the National Research Council,they were responsible for making certain that an independent examination of this reportwas carried out in accordance with institutional procedures and that all 'review commentswere carefully considered. Responsibility for the final content of this -report rests entirelywith the author committee and the National Research Council.GENERAL ACKNOWN'LEGEMENTSThe Committee thanks the Directors and Staff of the Radiation Effects ResearchFoundation, Hiroshima, Japan for providing the most current Life Span Study data on theJapanese atomic-bomb survivors. These data continue to be the primary source ofepidemiologic information on the relationship between exposure to ionizing radiation andxi
I Lits effects on human health. In particular, Dr. Donald Pierce was especially helpful incommunication between RERF and the Committee; also, he added his insightfulexperience to the work of the Committee.The Committee was aided in its consideration of its charge not only by commentsfrom the public but also by formal presentations by experts from a number of fields. Thefollowing presentations were made as part of the public portion of the meetings (in orderof appearance):Presentations by SponsorsJerome Puskin, Ph.D.Environmental Protection AgencyVincent Holahan, Ph.D.US Nuclear Regulatory CommissionBonnie Richter, Ph.D.US Department of EnergyScientific speakersJohn Boice, Ph.D.International Epidemiology InstituteEpidemiology that should be considered by BEIR VII.Charles Waldren, Ph.D.Colorado State UniversityAdaptive effects, genomic instability, and bystander effects.John Ward, Ph.D.University of California San DiegoDifferences between ionizing-radiation-induced DNA damage and endogenous oxidativedamage.Antone Brooks, Ph.D.Washington State University Tri-citiesOverview of projects funded by the DOE low-dose program.Charles Land, Ph.D.National Institute of HealthNCI's update of the 1985 NIH Radioepidemiologic Tables.L.B. Russell, Ph.D.Oak Ridge National LaboratoryEarly information derived from radiation-induced mutations in mice.xii\J
R. Chakraborty, Ph.D.University of Texas School of Public HealthMini- and microsatellite mutations and their possible relevance for genetic riskestimation.Allan Balmain, Ph.D.University of California, San FranciscoHigh and low penetrance genes involved in cancer incidence.Al Fomace, Ph.D.Harvard School of Public HealthFunctional genomics and informatics approaches to categorize radiation response.Steve Wing, Ph.D.University of North CarolinaThe relevance of occupational epidemiology to radiation risk assessment.Edward Calabrese, Ph.D.University of MassachusettsRadiation hormesis.David Utterback, Ph.D.National Institute of Occupational Safety & HealthExposure Assessment and Radiation Worker Studies.Sharon Dunwoody, Ph.D.University of WisconsinChallenges in the Communication of Scientific Uncertainties.Suresh Moolgavkar, Ph.D., M.B.B.S.School of Public Health and Community Medicine at the University of Washington andthe Fred Hutchinson Cancer Research CenterBiology-based models.We thank these presenters and all other members of the public who spoke onissues related to ionizing radiation.We thank Doris Taylor and Cathie Berkley for their administrative assistance inassuring that the members of the Committee showed up at the right place at the righttime. We also were aided in the work of the Committee by a talented group of ProgramAssistants. We thank Courtney Gibbs for her assistance in the preparation of thismanuscript. We thank Courtney Slack, a Christine Mirzayan Science and TechnologyPolicy Graduate Fellow who provided additional valuable assistance to NRC staff.We thank Dr. Evan Douple for pulling us in and for holding us together. His wiseand patient counsel along with his gentle encouragement, when needed, kept theCommittee focused on its charge.xiii
11j3.Finally, special thanks are due to Dr. Rick Jostes, the Study Director. Hisscientific expertise, persistence, equanimity, and organizational skills were essential toour staying the course.RICHARD MONSON, chairmanxiv
CONTENTSUNITS USED TO EXPRESS RADIATION DOSE.1PUBLIC SUMMARY.3INTRODUCTION .3HOW IONIZING RADIATION WAS DISCOVERED .:4.S5How IONIZING RADIATION IS DETECTED .5UNITS USED TO DESCRIBE RADIATION DOSE .WHAT WE MEAN BY Low DOSES OF IONIZING RADIATION.6:.6EXPOSURE FROM NATURAL "BACKGROUND" RADIATION .CONTRIBUTION OF MAN-MADE RADIATION TO PUBUC EXPOSURE .;8SCENARIOS ILLUSTRATING HOW PEOPLE MIGHT BE EXPOSED TO IONIZING RADIATION ABOVE BACKGROUND LEVELSBo S s . .W'.hole B ' ScansB o d .:'.10Working Near Ionizing Radiation .Veterans'Exposed to Radiation through Weapons Testing.:10.i. 12. 12.EVIDENCE FOR ADVERSE HEALTH EFFECTS SUCH AS CANCER AND .1.2.HEREDITARY DISEASE .;THE BEIR VISRISK MODELSCancer Risk.Health Effects Other Than Cancer.'.'.:EstimatingRisks to Children of ParentsExposed to Ionizing Radiation.WHAT BODIES OF RESEARCH THE COMMrITEE REVIEWED.y has-'the' committee not accepted the view that.;18.:.low doses are substantially more harmful than estimated by the linear no-threshold model? .18' 5'hy has the committee not accepted the view that.low doses are substantially less harmful than estimated by the linearno-threshold model?CONCLUSIONS .;:113::13-Estimating16. 1618191920E XECUTINrE SUNIMARY . . . . 21INTRODUCTION.21;;:21EVIDENCE FROM BIOLOGY .ESTIMATION OF HERITABLE GENETIC EFFECTS OF RADIATION IN HUMAN POPULATIONS .EVIDENCE FROM EPIDEMIOLOGY .23.23' 24Atomic bomb survivor studies . '.'.I;. 24Medical radiationstudies.:.;.'. 24Occupationalradiationstudies.:;: 25'Environmentalstudies.26INTEGRATION OF BIOLOGY AND EPIDEMIOLOGY26The principalconclusionsfrom this work are:. :.:.26ESTIMATING CANCER RISKS .2.7.-CONCLUSION.:.30BEIR VII RECOMMENDED RESEARCH NEEDS .:.301 BACKGROUND INFORMATION.3.34PHYSICAL ASPECTS OF RADIATION .Different Types of Ionizing Radiation.Photon Spectral Distributions.Different Effectiveness of yrays andx raysRadiation type,Relative Biological Effectiveness ofNeutronsCHEMICAL ASPECTS OF RADIATION.xV3434;;:3639. 414749
'IE-KElectron Ionization of Water Molecules and Indirect Effects on DNA. 49Spontaneous DNA Damage Relative to Radiation-InducedDNA Damage. SiBackground Radiation.S.3Locally Multiply DamagedSites .53MOLECULAR MECHANISMS OF DNA REPAIR . 55Base-Excision Repair.55Nucleotide-Excision Repair of Cyclodeoxynucleosides.58Nonhomologous endjoining-fast reaction.60Nonhomologous endjoining - slow reaction.63Homologous Recombination.63Double-Strand-BreakSignal Transduction and Inducible Repair.66SUMMARY .68ANNEX l-A IONIZING RADIATION AND OXIDATIVE DAMAGE- A VIEWPOINT FROM SACCHAROAfYCES CEREVsIsAE .702 MOLECULAR AND CELLULAR RESPONSES TO IONIZING RADIATION . . 74GENERAL ASPECTS OF DOSE-RESPONSE RELATIONSHIPS* .INDUCTION OF CHROMOSOME ABERRATIONS .INDUCTION OF GENE MUTATIONS IN SOMATIC CELLS .RADIATION-INDUCED GENOMIC INSTABILITY .CELL CYCLE EFFECTS .ADAPTIVE RESPONSE .BYSTANDER EFFECTS .HYPER RADIATION SENSITIVITY AT LOW DOSES .74777981848691OBSERVED DOSE-RESPONSE RELATIONSHIPS AT LOW DOSES .SUMMARY OF CHAPTER 2.94981073 RADIATION-INDUCED CANCER: MECHANISMS, QUANTITATIVE EXPERIMENTAL STUDIESAND TIlE ROLE OF GENETIC FACTORS.111INTRODUCTION.111MECHANISMS OF TUMORIGENESIS .112Gene and chromosomal mutations in spontaneously arisinghuman tumors. 112Mechanisms of radiationtumorigenesis.115Gene and chromosomal mutations in radiation-associatedhuman tumors.115Gene and chromosomal mutations in animal tumors. 117RADIATION-INDUCED GENOMIC INSTABILITY IN RADIATION TUMORIGENESIS.Chromatidinstability in hematopoietic cells.Chromatidinstability in mouse mammary epithelial cells .120120121QUANTITATIVE STUDIES IN EXPERIMENTAL TUMORIGENESIS . 124Generalaspects of dose-response.124Specifc Murine Neoplasms.126Fractionationkinetics .129Post-irradiationpersistenceof initiatedcells.130Radiation-inducedlife shortening1. 130DeterminingDose and Dose Rate Effectiveness Factorsfrom Animal Studies.132GENETIC SUSCEPTIBILITY TO RADIATION-INDUCED CANCER . 135Cancer-proneHuman Genetic Disorders.135Mechanistic Aspects of Genetically DetenninedRadiation Response.
Health Risks From Exposure to Low Levels of-Ionizing Radiation BEIRVII-Phase2 . Analysis of thos6 data would help to determine how regulatory bodies-should best characterize risks at the doses and dose rates experienced by radiation workers and members of the general public. BEIR-VII-phase 1 was the preliminary 'survey t6 evaluate
