Assessment Of Risk From Low-level Exposure To Radiation And Chemicals: A Critical Overview (basic Life Sciences)

The present workshop had its orlglns in discussions among Alexander Hollaender, Oddvar Nygaard, Donald Borg, Richard Setlow and Victor Bond on the need for a symposium that would deal with a broad spectrum of pressing subjects related to the physics, chemistry, and biological actions of ionizing radiations, and the theoretical and practical problems of risk assessment. It soon became apparent that the spectrum of subjects considered was too broad for the desired depth of coverage; in fact, it seemed un­ likely that the conference participants would have the background knowledge to span the gamut. Therefore, two separate meetings were decided upon, the first of which, Comparison of Mechanisms of Carcinogenesis by Radiation and Chemical Agents, was held at the National Bureau of Standards, Gaithersburg on December 6-7, 1983. The meeting was sponsored by the NCI. The second meeting has emerged as the present workshop at Brookhaven National Laboratory. An interface between the two conferences has been provided by Michael Fry and Donald Borg, who have summarized the salient points emanating from the NCI Symposium. We intended that the first conference should focus on the basic mechanisms of radiation and chemical carcinogenesis, while the second, the present meeting, would emphasize exposure-response relationships, particularly the theoretical and practical similar­ ities and differences between exposure to chemical carcinogens compared to exposure to ionizing radiation. Front Matter....Pages i-xii Dedication: To Our Colleague and Friend Dr. Charles Little Dunham....Pages 1-1 Epidemiological Reservations about Risk Assessment....Pages 3-16 Common Molecular Mechanisms....Pages 17-42 Cellular and Animal Models....Pages 43-63 What are We Doing When We Think We are Doing Risk Analysis?....Pages 65-76 The Control of Mutagenesis and Cell Differentiation in Cultured Human and Rodent Cells by Chemicals that Initiate or Promote Tumor Formation....Pages 77-100 The Role of Mechanistic Data in Dose-Response Modeling....Pages 101-124 Statistical Aspects of the Estimation of Human Risks....Pages 125-140 The Isolation and Characterization of the Blym-1 Transforming Gene....Pages 141-152 Retroviral Oncogenes and Human Neoplasia....Pages 153-168 Mutation in Single-Cell Systems Induced by Low-Level Mutagen Exposure....Pages 169-204 Quantitative Neoplastic Transformation in C3H/10T1/2 Cells....Pages 205-222 Risk Estimate for Genetic Effects....Pages 223-250 Saturation of Repair....Pages 251-260 Role of Tumor Promotion in Affecting the Multi-Hit Nature of Carcinogenesis....Pages 261-284 Genetic and Epigenetic Aspects of Tumor Progression and Tumor Heterogeneity....Pages 285-305 Interaction of Ionizing Radiation and 8-Methoxypsoralen Photosensitization: Some Implications for Risk Assessment....Pages 307-318 Low-Level Exposures To Chemical Carcinogens: Mutational End Points....Pages 319-328 Radiogenic Neoplasia in The Thyroid and Mammary Clonogens: Progress, Problems and Possibilities....Pages 329-344 Induction and Manifestation of Hereditary Cataracts....Pages 345-367 Extrapolation from Large-Scale Radiation Exposures: Cancer....Pages 369-391 The Feasibility and Urgency of Monitoring Human Populations for the Genetic Effects of Radiation: The Hiroshima-Nagasaki Experience....Pages 393-413 Prospects for Cellular Mutational Assays in Human Populations....Pages 415-427 Cytogenetic and Allied Studies in Populations Exposed to Radiations and Chemical Agents....Pages 429-451 Front Matter....Pages 453-453 Where the Future? Part I — Round Table Discussion....Pages 455-468 Where the Future? Part II — Round Table Discussion....Pages 469-482 The Agent Carrier and Transfer Approach to Radiobiological Responses....Pages 483-506 Back Matter....Pages 507-529