Advances in Radiation Biology, Volume 6: Effects of Low Dose and Low Dose Rate Radiation examines the biological effects of low dose and low dose rate ionizing radiation on a broad scale, covering various articles from microdosimetry to analyses of human responses. Estimates of the effects on humans from low doses or from sustained exposures to low dose rates of ionizing radiations are of critical importance for the assessment of radiation risks under occupational and environmental conditions. This book consists of such knowledge that is essential for radiation protection and governmental regulatory activities pertaining to radiation exposure. This volume is intended for radiobiologists, radiation epidemiologists, radiation physicists, radiation safety personnel, health officials, and individuals involved in regulatory activities.

PrefaceIntroduction and OverviewTrack Structure Considerations in Low Dose and Low Dose Rate Effects of Ionizing Radiation I. Introduction II. Features of Radiation Tracks III. Dose Responses and Extrapolation to Low Doses IV. Conclusions ReferencesDose-Time-Response Models for Radiation Carcinogenesis I. Introduction II. Descriptive Models III. Radiobiological Principles IV. Mechanistic Models V. Directions of Future Research VI. Conclusions ReferencesRadiation-Induced Mutation in Mammalian Cells at Low Doses and Dose Rates I. Introduction II. Mutation Measurements III. Comment on Mutation Data IV. Novel Mutation Systems: Enhancing Mutant Detection V. The Bottom Line(s) Appendix 1: Mammalian Cell Line Sensitivities Appendix 2: A Brief Survey of the Nature of Radiation-Induced Mutations References Commentary to Thacker: A Consideration of the Mechanisms of Induction of Mutations in Mammalian Cells by Low Doses and Dose Rates of Ionizing Radiation I. Introduction II. DNA Damage, Repair, and Mutations III. Mechanism of Induction of Chromosomal Mutations by Ionizing Radiations IV. Mutation Induction (Chromosomal and Point) by Ionizing Radiation V. Conclusion ReferencesOncogenic Cell Transformation In Vitro I. Introduction II. Cellular and Molecular Events in Oncogenic Transformation III. Choice of Cellular Systems: Criteria and Endpoints for Oncogenic Transformation IV. In Vivo Correlations of Transformation In Vitro V. Concluding Remarks: Future Research Directions ReferencesCommentary 1 to Cox and Little: The Unbridged Gap between In Vivo and In Vitro Models for Evaluation of Low Dose, Low Dose Rate Radiation-Induced Oncogenic Transformation I. Introduction II. Stages of Neoplastic Development III. Model Systems for Studying Neoplastic Progression IV. Summary ReferencesCommentary 2 to Cox and Little: Radiation-Induced Oncogenic Transformation: The Interplay between Dose, Dose Protraction, and Radiation Quality I. Introduction II. Review of Pertinent Experimental Data III. Biophysical Modeling of Inverse Dose Rate Effects IV. Practical Consequences in the Field of Radiation Protection V. Conclusions ReferencesThe Role of Animal Experiments in Estimates of Radiation Risk I. Introduction II. Stochastic Effects III. The Use of Experimental Data: Qualitative and Quantitative IV. Protracted and Low Dose Rate Studies V. Transfer to Risk Estimates across Populations VI. Summary ReferencesCommentary to Fry: Radiation Carcinogenesis Studies in Animals-Advantages, Limitations, and Caveats I. Introduction II. Random Processes and Carcinogenic Effects III. Molecular Biology of Radiation Carcinogenesis IV. The Grade of Malignancy and the Absorbed Dose V. The Relative Biological Effectiveness of High Linear Energy Transfer Radiation VI. Influence of the Time Factor for High Linear Energy Transfer Radiation VII. Caveats of Cancer Risks for Humans ReferencesRadiation Carcinogenesis in Humans I. Introduction II. Carcinogenesis III. Conclusions ReferencesCommentary 1 to Schull and Weiss: Low Dose Extrapolation, Time following Exposure, and Transport between Populations I. Low Dose Extrapolation II. Changes in Excess Risk over Time following Exposure III. Transport of Risk Estimates from One Population to Another ReferencesCommentary 2 to Schull and Weiss: Human Cellular Radiosensitivity - The Search for the Diagnostic Holy Grail or a Poisoned Chalice I. Introduction II. The Response of Individuals III. Measurements of Cellular Radiosensitivity IV. Genetically Disposed Individuals V. Modifications to Survival Assays VI. Sensitivity of Tumor-Derived Cells VII. Other Assays VIII. Conclusions and the Future ReferencesCommentary 3 to Schull and Weiss: Increased Definition of Abnormal Radiosensitivity Using Low Dose Rate Testing I. Introduction II. Evidence for DNA Repair Involvement in Cases of Protection at Low Dose Rates III. Chronic Exposure Expands the Range of Radioresponse IV. Increased Resolution of Mildly Hypersensitive Responses Is Possible with Chronic Dose Delivery V. Possible Mechanisms of Protection on Dose Rate Protraction ReferencesRadiation Protection: Recent Recommendations of the ICRP and the NCRP and Their Biological Basis I. Introduction II. History of ICRP and NCRP Recommendations III. Deterministic Effects, Stochastic Effects, and Detriment IV. The Risk of Radiation-Induced Cancer to 1985 V. Recent Evaluations of the Risk of Radiation-Induced Fatal Cancer VI. Uncertainties in Risk Coefficients for Fatal Cancer VII. Tissue Weighting Factors (wT)and Detriment VIII. Radiations Other Than Low Linear Energy Transfer X and Y RaysReferencesIndex