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A Historical Study of Chemical Dosimetry (1902-1962)

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A Historical Study of Chemical Dosimetry (1902-1962) AN ABSTRACT OF THE THESIS OF Sister Mary And/4 Chorzernpafor the Doctor of Philosophy (Name) (Degree) in General Science presented on 7/","/9>vii (Major) (Dte) Title: IONIZING RADIATION AND ITS CHEMICAL EFFECTS: A HISTORICAL STUDY OFCHEIOgNI/DIMETRY/(1902-1962) Redacted for privacy Abstract approved: RobeVJ. Morris Chemical dosimetry developed in response to needs created by developments in the field of high-energy radiation.Shortly after the discovery of X-rays in 1895 and of radioactivity in 1896, the deleterious effects of ionizing radiation were recognized. To guard against the injurious effects of radiation in medical application, dose-measuring methods were considered necessary. The early dosimetric methods were based on what at the time were taken to be the chemical effects of ionizing radiation.In 1902, Guido Holzknecht (1872-1931), a Viennese physician, suggested a method of dosimetry which was based on the coloration of a salt due to irradiation.His proposal, the first of its kind, was followed within about five years by a number of others which were made by other physicians and radiologists and which were based on some visible chemical change.Subsequent developments in chemical dosimetry until about 1915 were concerned mainly with the calibrated scales used to relate the chemical change to dose, the problem being a lack of a radiation unit of dose. Further investigations of chemical systems for dosimetry were not made, however, until in the 1920's.In the meantime ionization methods of dosimetry became popular, although some of the earlier- proposed chemical dosimeters were widely in use.The renewal of interest in the chemical effects of ionizing radiation in the 1920's stemmed from the extensive radiobiological research that was con- ducted owing to the expanded application of higher-energy X-ray units in medicine and in industry. From the research done to understand better the mechanisms underlying biochemical processes, there pro- ceeded several dosimetric systems.The one that proved most reliable was the ferrous sulfate system recommended in 1927 by the biophysicist Hugo Fricke (b.1892).This renewed research on the chemical effects of ionizing radiation also made some significant contributions for future developments in chemical dosimetry. Most fundamental, both to the developing theories of radiation chemistry as well as to the formula- tion of many dosimetric systems in the post-World War II period, was the observation made by Fricke and associates that the primary action of the radiation was on the solvent rather than the solute. The discovery of the neutron and of artificial radioactivity and the development of accelerating devices in the 1930's provided for still further application of ionizing radiation in medicine and in industry which increased the number of persons whose occupation was a source of radiation exposure. A growing concern for the protection of person- nel contributed to attempts at standardizing dosage measurements. Although formal standardization began in 1928 when the roentgen was officially defined as a radiation unit by the International Commission on Radiological Units, it was not until 1962 that the rad was officially restricted as a unit of dose and the roentgen as a unit of exposure.The precision of the terminology contributed to more reliable dosimetry. The development of reactor technology in the 1940's gave rise to new problems in radiation protection.To monitor the mixed radiation fields present in the vicinity of nuclear reactors, film badges had to be modified for the detection of various forms of radiation.Also, various filter assemblies were introduced into the badge to reduce the energy dependence of photographic emulsions, thus to improve the accuracy of the film dosimeter. Research in radiation chemistry and in nuclear technology in the post-war period called for dosimetric methods useful over a wide range of dosage and not necessarily as sensitive as those requ,ired by research in medicine and radiobiology. As a result, chemical dosimetric sys- tems effective over a range from about 10 to1010rads were made available.Although many of the systems were formulated on the basis of the indirect action of the radiation on the solute via the solvent, not every system had a comparable reliability nor did each meet all the requirements desirable of a dosimetric system. Ionizing Radiation and Its. Chemical Effects: A Historical Study of Chemical Dosimetry (1902-1962) by Sister Mary Andre Chorzempa A THESIS submitted to Oregon State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy June 1971 APPROVED:Redactedfor privacy Associate Professor of 1-listioryof-Scienceg icharge of majtr Redacted for privacy Chairman of Department of General Science Redacted for privacy Dean of Graduate School Date thesis is presented 4'/4/92e Typed by Gwendolyn Hansen for Sister Mary Andre Chorzempa ACKNOWLEDGEMENT I wish to express my appreciation to all who have helped me in the completion of this study: To the members of my doctoral committee for their willing assistance whenever problems arose, especially to Dr. Robert J. Morris for the helpful discussions in the course of this study and for his critical evaluation of it. To Dr. E. Dale Trout and his staff for the generous use of the library facilities at the X-ray Science and Engineering Laboratory at Oregon State University. To the various radiation laboratories for their ready response with pertinent information, specifically the Health Physics Division at Oak Ridge National Laboratory, the Radiation Protection Staff at Richland, Washington, and the Health Physics Department at the Lawrence Radiation Laboratory in Berkeley. To the staff at the Institute for the History of Medicine at the University of Vienna for supplying significant data about the founda- tions of chemical dosimetry. To Dr. Milton Burton of the Radiation. Laboratory at the University of Notre Dame for his valuable comments about certain aspects of this study. Finally, I wish to extend a special word of thanks to the Sisters of St. Francis of Sylvania, Ohio, who have granted me the financial sponsorship and the required leave-of-absence from the teaching apostolate to make this study. Note: The various units used throughout this treatise are represented by the symbols which were used by the writers whose works have been studied.These symbols do not always conform with modern accepted usage. TABLE OF CONTENTS Chapter Page I.IONIZING RADIATION PRIOR TO 1925 1 X-radiation: Discovery and Application 3 Radioactivity: Discovery and Application 15 II,CHEMICAL DOSIMETRY (1902-1925) 25 Dosimetry Based on Colorimetry 30 Dosimetry Not Based on Colorimetry, 44 Chemical Dosimetry in Developmental Perspective 47 III.IONIZING RADIATION (1925-1942) 50 The Discovery of Neutrons 51 The Early Development of Particle Accelerators 55 The Cyclotron in Medicine 60 Neutron Beams 60 Radioisotope s 65 Developments in Medical Radiology 67 Developments in Industrial Radiology 69 Ionizing Radiation, in Development Perspective 72 IV. CHEMICAL DOSIMETRY (1925-1942) 75 Developments in Radiation Protection 75 Recommendations of the ICRU 77 Recommendations of the ICRP 78 Chemical Dosimetry and Stray Radiation 80 Chemical Dosimetry and. Therapeutics. 83 Chemical Dosimetry in Development Perspective 107 V. IONIZING RADIATION (1942-1962) 111 Prelude to the Manhattan Project 112 The Manhattan Project and the Development of a Reactor 116 The Atomic Pile: Peacetime Applications 126 Source of Useful Power 126 Source of Radioactive Isotopes 129 Ionizing Radiation in Developmental Perspective 142 Chapter Page VI. CHEMICAL DOSIMETRY IN PERSONNEL: MONITORING (1942-1962) 147 Developments in Radiation Protection 148 Conceptual Developments Regarding Dose 149 Changes in Levels of Tolerance Dose 153 Absorbed Dose Determination 155 Developments in Personnel Monitoring 158 X- and Gamma-radiation 158 Mixed Radiation Fields 172 Photographic Dosimetry in Developmental Perspective 179 VII. CHEMICAL DOSIMETRY (1942-1962) - PART I 187 Aqueous Systems 191 Chlorinated Hydrocarbon Systems 207 VIII.CHEMICAL DOSIMETRY (1942-1962) - PART II 229 Dye Systems 229 Monomer-Polymer Systems 242 Gas Systems 261 Chemical Dosimetry in Developmental Perspective 265 IX. SUMMARY AND CONCLUSIONS 268 BIBLIOGRAPHY 277 LIST OF TABLES Table Page 1.Final NTA-film packet. 176 2.G Values for the Fricke Dosimeter._ 195 3.Color changes in four series of mixed, indicator solutions. 227 4.Summary of reversible yields of an air-free methylene blue dosimeter under various conditions. 236 5.Gel doses of several monomers at 3000 rads/min. 247 LIST OF FIGURES -Figure Page 1.The action of different doses of X-rays on 0. 00033 M ferrosulfate in 0.8<N sulfuric acid. 89 2.The action of different doses of X-rays on 0.00100 M ferrosulfate in 0.8 N sulfuric acid. 89 3.Weights of HgC1 obtained by irradiating for different periods of time an Eder's solution of convenient strength. 95 4.Curve showing relation between amount of precipitate and time of irradiation--all other factors remaining constant--in an Eder's solution dosimetric system. 97 5.Decomposition of methylene blue by roentgen irradiation. 102 6.Life history of 100 neutrons in an atomic pile. 123 7.Absorbance at 5950 X (lower co-ordinates) and 6500 X (upper co-ordinates) as a function of phenol concentration in an irradiated aqueous benzene system. 205 8.Reduction of rate dependency in acid production from chloroform by varying concentrations of resorcinol in a two-phase
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