Biomedical and Aerosol Studies Associated with a Field Release of Plutonium

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AEG Category: BIOLOGY AND MEDICINE NEVADA TEST SITE Test Group 57, Program 72 BIOMEDICAL AND AEROSOL STUDIES ASSOCIATED WITH A FIELD RELEASE OF PLUTONIUM Issuance Date: February 6, 1961 COAACAIIOH ALBUOUEROUE, NEW MEXICO

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This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency Portions of this document may be illegible in electronic image products. Images are produced from the best available

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This report is published in the interest of providing information which may prove of value to the reader in his study of effects data derived principally from nuclear weapons This document is based on information available at the time of preparation which may have subsequently been expanded and re-evaluated. Also, in preparing this report for publication, some classified material may have been removed. Users are cautioned to avoid interpretations and conclusions based on unknown or incomplete data. PRINTED IN USA Price $1.75. Available from the Office of Technical Services, Department of Commerce. USAEC Office of Technical Information Extension Oak Ridge, Tennessee

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Operation Plumbbob - Test Group 57, Program 72 BIOMEDICAL AND AEROSOL STUDIES ASSOCIATED WITH A FIELD RELEASE OF PLUTONIUM and J. Newell Stannard University of Rochester Atomic Energy Project Rochester, New York

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On April 24, 1957, a high-explosive detonation was employed at the Nevada Test Site to release plu tonium for field study of this fissile material as a contaminant. One of four major measurement programs was a biomedical experiment which comprised exposure of animals to first deposition of plutonium oxide from the detonation cloud (acute subjects) and to the wind-induced resuspension of contamination (chronic subjects) as long as six months after original deposition. Acute subjects (26 dogs and 40 rats) were arrayed 500, 1000, and 2000 feet downwind from ground zero, and nine rats were flown on balloon cables positioned to intercept the cloud 500 feet from ground zero. Chronic subjects (three groups of 24 dogs and 3 burros) were placed, after a rough ground-activity survey, at climatologically probable downwind segments of isopleths marking nominal contaminations of 1000, 100 and 10 (igm of plutonium per square meter. Serial sacrifices of dogs were made at 4, 5, 16, 32, 64, 128, and 161 days after detonation. Ten tissues per animal were assayed by radiochemistry and auto radiography for plutonium content. All burros received the full 161-day exposure. Ten sheep were dis tributed among the three field positions on the 32nd day, at which time four additional dogs were placed at the middle position (100-line). All late animals stayed until the end of the maximum exposure period. Air samplers at each chronic field position documented daily mean air concentrations. The pattern of plutonium uptake was surprising in that statistically important numbers of acute and chronic animals showed significant bone burdens in an exposure situation for which lung alone was to have been the critical organ. This outcome was most unusual for acute animals sacrificed less than four hours postdetonation. In general, however, all uptakes were less than the forecast amounts. The factor of 100 difference between ground-level contamination at near and far chronic stations brought uptake differences of less than a factor of ten to indicate that airborne material accumulates along the upwind path. Air con centrations bear small if any relation to the "at foot" contamination for natural resuspension forces (wind). An explanation is advanced for the fact that, in an experiment designed to find time dependence in plutonium uptake, no tissues measured exhibited a correlation with exposure time, save GI tract and con The plutonium found in bone suggests some deviation from the pure oxide form (extremely insoluble in body fluids) and the presence of solubilizing influences either in early particulate formation or in animal lung. As yet no believable mechanism has been proposed. All autoradiography gave negative results.

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It is important that contributions made by Sandia Corporation personnel towards the success of this program be recognized. In particular, the work accomplished by William Kingsley, Supervisor of the Industrial Hygiene Division, and by his analytical section under Robert Elsbrock, should be emphasized. Literally thousands of tissue and air samples were prepared for plutonium analysis, a notoriously tedious Activity analysis of the prepared samples was carried out under the direction of Harold Rarrich, also of the Industrial Hygiene Division, following a counting procedure developed by Dr. George Steck of the Analysis Division. Dr. Joan Longhurst of the Nuclear Burst Studies Division provided an evaluation of tissues (Appendix A) based on autoradiographic studies. The efforts of these and others of Sandia con tributed materially to the successful conclusion of Program 72.

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CHAPTER 1 INTRODUCTION AND BACKGROUND 13 CHAPTER 2 EXPERIMENTAL DESIGN 14 2. 6 Routine Animal Care 23 CHAPTER 3 BIOMEDICAL PROGRAM RESULTS 26 3. 1 Biomedical Program Data 26 3. 3 Analysis of Data 36 3. 6 Summary of Biological Results 40 CHAPTER 4 AIR SAMPLING PROGRAM 41 4. 1 Air Sampling Procedures 41 4. 3 Analysis of Results 43 APPENDIX A AUTORADIOGRAPHIC EVALUATION OF TISSUES FROM PROGRAM 72 APPENDIX B MATHEMATICAL EVALUATION OF LUNG BURDEN AS A FUNCTION APPENDIX C TISSUE ANALYSIS VALUES 65

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CHAPTER 2 EXPERIMENTAL DESIGN 2. 2 Floor plan of laboratory trailers 17 2. 3 Layout of cloud passage (acute) array 20 2. 4 Layout of chronic array 22 CHAPTER 3 BIOMEDICAL PROGRAM RESULTS 3. 2 Gastrointestinal tract burdens of acute animals as a function of time 39 3. 3 Gastrointestinal tract burdens of lO-figm/m^ animals as a function of time 39 3. 4 Gastrointestinal tract burdens of lOO-ngm/m^ animals as a function of time 39 3. 5 Gastrointestinal tract burdens of 1000-«gm/m2 animals as a function of time 39 CHAPTER 4 AIR SAMPLING PROGRAM 4. 1 Histogram of frequency of occurrence of stated mass median diameters 46 4. 2 Weekly means of mass median diameters 47 4. 3 Median weekly air concentrations 48 4. 4 Rate of buildup of total air sample for lO-ngm/m^ line 51 4. 5 Rate curves for determination of time to maximum lung burden 52 CHAPTER 3 BIOMEDICAL PROGRAM RESULTS 3. 1 Plutonium Concentration in Tissues of Chronic Dogs and Burros on lO-pgm/m^ 3. 2 Plutonium Concentration in Tissues of Chronic Dogs and Burros on 100-/ugm/m2 3. 3 Plutonium Concentration in Tissues of Chronic Dogs and Burros on 1000-pgm/m2 3. 4 Plutonium Concentration in Tissues of Acute Dogs and Rats Exposed to the Cloud, and of Acute Dogs Remaining in Field after Cloud Passage 30 3. 5 Mean and Median Tissue Weights of All Animals Sacrificed in Program 72 32 3. 6 Median Plutonium Concentration in Dog and Burro Tissues 32 3. 7 Median Plutonium Concentration in Tissues of Animals Placed in Field at P Plus 3. 8 Data on Lung and Gastrointestinal Tract Plus Contents 33 3. 9 Maximal Median Radiation Dose Rates to Dog and Burro in REM perWeek 34 3. 10 Dosage Relationship Between Dog and Man for the Case of anAccident 34 3.11 Maximal and Effective Dose Rates to Man Based on Median Dog Values 36 3. 12 Fraction of Tissues of Possibly Insignificant Plutonium Concentration 37 3. 13 Effective Dose Rates to Man 37 3. 14 Tissue Contents of Seven Dogs Sacrificed at P Plus 520 Days 40 CHAPTER 4 AIR SAMPLING PROGRAM 4. 1 Summary of Exposure Period Sampler Information 50 APPENDIX A AUTORADIOGRAPHIC EVALUATION OF TISSUES FROM PROGRAM 72 ANIMALS A. 1 Tissues Examined by Autoradiography 55 A. 2 Activity Found in Solutions Used in Tissue Preparation 57

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APPENDIX C TISSUE ANALYSIS VALUES C. 1 Plutonium Content in Tissues of Chronic Dogs and Burros on the lO-pigm/m2 C. 2 Plutonium Content in Tissues of Chronic Dogs and Burros on the 100-ngm/m2 C. 3 Plutonium Content in Tissues of Chronic Dogs and Burros on the 1000-ygm/m2 C. 4 Plutonium Content of Tissues from Animals Exposed to the Cloud 70

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INTRODUCTION AND BACKGROUND Considerable discussion has centered around the problem of acceptable levels of ground contamination when the contaminating agent is plutonium. The development of weapons with plutonium-bearing components has led to increased concern over this problem, particularly with regard to transportation and storage. The Nuclear Safety Working Group, which is made up of representatives of the Atomic Energy Commission, the Department of Defense, and various contractors, is charged with establishing criteria for both of these situ ations, and in the past has been forced to do so primarily on conjectural and hypothetical bases. In 1956, an experimental detonation was carried out in Area 11, east of Yucca Lake, at the Nevada Test Site. This test served chiefly to indicate the complexity of the problem of evaluating the phenomena associated with a release of this nature. Consequently, when the decision was made by AEC and DOD to repeat the experiment, it was with prior knowledge of the required scope of such a test, and plans were laid for an unusually extensive field operation. As originally conceived, the experiment called for release and dispersal of plutonium by detonation of conventional high explosive, simulating a nonnuclear explosion of an assembled plutonium-bearing weapon. As planning progressed, four distinct programs began to evolve: (1) a study of cloud behavior and particulate physics; (2) a biological study to aid in evaluation of health hazards; (3) a study of decontamination procedures which might be used in the event of an accidental detonation; and (4) a study of monitoring procedures which might be useful in quickly delineating the extent of spread of contamination. In the early planning stages, representatives of the University of Rochester Atomic Energy Project were asked to act as consultants to the biological program, with some other organization actually performing the work. As time went on, it became evident that the University of Rochester was the only organization not already involved in Operation Plumbbob capable of performing studies of this kind. As a consequence, in early February 1957, the University was requested by the Atomic Energy Com mission to undertake the biomedical program for Test Group 57. The first ready date was April 10, 1957. Generous support was given both by the Atomic Energy Commission and by the Department of Defense. The latter, in addition to supplying part of the funding, provided two veterinary officers and a number of enlisted men to perform the work in this program. As finally constituted. Program 72 of Test Group 57 consisted of Dr. J. Newell Stannard, Program Director; Robert H. Wilson, Director of Field Operations; Dr. Robert G. Thomas, Director of Laboratory Operations; Lt. Col. Roy Kyner, USAF veterinarian; and Capt. Ralph Thomas, U. S. Army veterinarian. The enlisted personnel (approximately 20) were about evenly divided between Air Force and Army Veterinary Corps. Sfc. Warren A. Gramly was Noncom missioned Officer in Charge of enlisted personnel. Test Group 57 was under the direction of Dr. James D. Shreve, Jr. of Sandia Laboratory. Results of the other three programs of TG-57 are contained in other reports.1' 2, 3, 4 * These were designated as Programs 71, 72, 73, and 74, respectively.

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Early in the planning stages of the experiment it was recognized that there were three clear-cut types of exposure which should be simulated: (a) the acute situation, resulting from exposure to the cloud for the duration of its passage, with subsequent evacuation; (b) the chronic case, resulting from reinhabiting the area an indeterminate time after cloud passage; and (c) the combination case, with exposure to both the initial cloud and subsequently resuspended material. Each of these cases represents a possible situation with regard to human exposure following an acci dental release; an evaluation of each was expected to provide information of benefit in determining the hazard to different populations (i. e. , transients in the path of the cloud, decontamination crews sent in to remedy the situation, or permanent residents in the fallout pattern) exposed to such an accident. Operationally, logistics is a vital part of successful field experiments, and particularly was this true for Program 72 of TG-57 because of its biological aspects. First, the Nevada Test Site is remote from biological supply houses, and second, support facilities at the site, while extensive, are primarily me chanical and physical in nature and were not geared to biological studies of the type required for this test. As a consequence, it was necessary to anticipate needs to the utmost, and over 10, 000 pounds of supplies, ranging from string and masking tape to surgical instruments and equipment, were collected in Rochester. To this accumulated material were added 83 dogs (beagle or beagle-type). Two enlisted men from the U. S. Army Veterinary Corps were assigned to the program to care for the dogs prior to and In order that the animals be subjected to a minimum of hardship in transit, a Flying Tiger C-46 was chartered to fly them, together with all supplies and four attendants, from Buffalo, N. Y. to Indian Springs Air Force Base, twenty miles east of Mercury, Nevada. The dogs were housed in specially constructed, heavy corrugated cardboard boxes lined with 1/2-inch hardware cloth, 15 inches wide, 24 inches long, and 22 inches high. These boxes were designed with disposal in mind, since it was anticipated that they would also be used in the test field and hence would be liable to heavy contamination. The philosophy of disposal, therefore, seemed preferable to decontamination. These boxes served well, except that certain unusually resourceful dogs managed to escape from several boxes by popping the staples loose. The flight was uneventful, save for a 24-hour delay, caused by a defective carburetor, and the escape of two or three dogs from their boxes (though still in the plane). Transhipment to Mercury was accom plished with the help of DOD motor pool personnel and equipment. The program was permitted to set up in existing animal facilities erected by the Civil Effects Test Group until such time as facilities specifically for Program 72 could be established. In addition to an oper ations building (the "Mouse House"), the CETG facilities included a dog kennel and a sheep pen which was modified for dog quarters. For the most part, dogs were quartered two to a cage. The kennel had outside runs for each cage, while the modified sheep pen provided two large fenced areas for exercise yards into which the sex-segregated dogs were released while their cages were cleaned. A second group of 26 dogs was procured from the dog colony at the University of California Agricultural …