PAH • Ill Work Atmospheres: Occurrence and Determination Editors Alf Bj~rseth, Dr. phil. Director Petroleum Research Center Norsk Hydro Bergen, Norway Georg Becher, Dr .rer .nat. Head, Chemical Laboratory of Toxicology National Institute of Public Health Oslo, Norway Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business First published 1986 by CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 Reissued 2018 by CRC Press © 1986 by CRC Press, Inc. CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. 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CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data BjØrseth, Alf. PAH in work atmospheres Bibliography: p. Includes index. 1. Polycyclic aromatic hydrocarbons--Toxicology. 2. Polycyclic aromatic hydrocarbons--Environmental aspects. 3. Polycyclic aromatic hydrocarbons--Metabolism. 4. Polycyclic aromatic hydrocarbons--Measurement. 5. Industrial toxicology. I. Becher, Georg. II. Title. RA1242.P73B56 1986 616.99’4’071 85-30731 ISBN 0-8493-6064-1 A Library of Congress record exists under LC control number: 85030731 Publisher’s Note The publisher has gone to great lengths to ensure the quality of this reprint but points out that some imperfections in the original copies may be apparent. Disclaimer The publisher has made every effort to trace copyright holders and welcomes correspondence from those they have been unable to contact. ISBN 13: 978-1-315-89621-2 (hbk) ISBN 13: 978-1-351-07531-2 (ebk) Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com PREFACE Polycyclic aromatic hydrocarbons (PAH) are a group of chemical compounds that are strongly suspected of exhibiting carcinogenic effects in humans. This suspicion is based on long-term observation, i.e., in animal bioassays, occupational medicine, and epidemiology. Such observations have been made for a long time. The earliest association of a human cancer with exposure to an environmental hazard was made more than two centuries ago by Sir Percivall Pott who reported an increased incidence of scrotal cancer among chimney sweeps. The coal soot, suspected to be responsible for this scrotal cancer, was not known until Kennaway and his colleagues reported their work in the 1930s. Since that time, ample evidence has been generated showing that increased industrialization and man's use of fossil fuels result in a wide distribution of PAH in the environment. Particularly high levels of PAH are to be found in occupational environments. This book deals with the sources, distribution, analytical methods, and monitoring of PAH in the occupational environment. It is our hope that the publication of this book will make a contribution to understanding the formation and determination of PAH in work atmosphere and that it will make a particular contribution to occupational health projects. Much of the information given in this book has been generated in studies carried out in cooperation with the Norwegian aluminum industry. The financial contribution to this work from the Nordic Aluminum Industry's Secretariat for Health, Environment, and Safety is gratefully acknowledged. The authors would also like to acknowledge the inspiring working conditions provided by the colleagues at the Center for Industrial Research in Oslo. THE EDITORS AlfBj0rseth, Dr. phil., graduated from the University of Oslo in 1969 with a background in mathematics, physics, and chemistry with particular emphasis on physical chemistry. He finished his doctorate in 1979 in Environmental Chemistry. Dr. Bj0rseth is currently Director of Norsk Hydro's Petroleum Research Center in Bergen, Norway. His previous engagements include Research Manager in the Chemistry Division of the Central Institute for Industrial Research in Oslo, Norway and Associate Section Manager at Battelle Columbus Laboratories in Columbus, Ohio. He is also co-founder of the Scandinavian Center for Advanced Technology (SCATEC). Dr. Bj0rseth's research interests include studies of polycyclic aromatic hydrocarbons and their transformation prod ucts - with emphasis on the application of high resolution gas and liquid chromatographic techniques. Dr. Bj0rseth has published over 60 papers in these areas, authored and edited several books, given a number of lectures in the U.S. and Europe, and chaired international symposia devoted to polycyclic aromatic hydrocarbons. He is a member of the Norwegian Chemical Society and Norwegian Petroleum Society where he is currently serving as President of the Bergen Division. Georg Becher, Dr .rer .nat., is Head of the Chemical Laboratory in the Department of Toxicology at the National Institute of Public Health in Oslo, Norway. Dr. Becher obtained his M.S. and Ph.D. degrees in 1970 and 1974, respectively, from the Department of Organic Chemistry, University of Gottingen, West Germany. He did his postdoctoral work at the Department of Chemistry, University of Oslo, Norway and served as an Assistant Professor at the Department of Chemistry, University of Regensburg, West Germany. In 1979, he joined the Environmental Chemistry Department at the Central Institute for Industrial Re search in Oslo as a research scientist. Since 1983, Dr. Becher is in his present assignment at the National Institute of Public Health in Oslo. Dr. Becher has been a recipient of the postgraduate fellowship of the Funds of Chemical Industry, West Germany and is a member of the German and the Norwegian Chemical Society. Dr. Becher is currently engaged in the analyses of trace quantities of potentially hazardous compounds in environmental samples. Among others, he is interested in the development of new methods for determination of human exposure to PAH. TABLE OF CONTENTS Chapter I PAH as Occupational Carcinogens .................................................... . I. Historical Review ................................................................. 1 II. Epidemiological Evidences for Cancer Risk from PAH ........................... 2 A. Chimney Sweeps .......................................................... 2 B. Aluminum Workers ....................................................... 4 C. Coke Oven and Steel Workers ............................................ 6 D. Iron and Steel Foundry Workers .......................................... 9 E. Asphalt and Tar Workers ................................................. 10 III. Summary and Conclusion ........................................................ 11 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Chapter 2 Mode of PAH Formation .............................................................. 15 References ............................................................................... 18 Chapter 3 Physical and Chemical Properties of PAH ............................................ 21 I. Chemical Structure and Nomenclature ........................................... 21 II. Physical Properties ............................................................... 23 III. Atmospheric Forms of PAH ..................................................... 28 IV. Chemical Reactivity ............................................................. 29 A. Oxidation Reactions ...................................................... 30 B. Reactions with Oxides of Nitrogen and Sulfur ........................... 30 V. Summary and Conclusion ........................................................ 31 References ............................................................................... 32 Chapter 4 Sources and Exposure .................................................................. 35 I. Sources of P AH in the Work Environment ...................................... 35 A. Coke Production .......................................................... 35 1. Historical Perspectives ............................................ 35 2. Coal Characteristics ............................................... 35 3. Structure and Operation of a Coke Plant. ......................... 35 4. Major By-Products ................................................ 37 5. Personnel ......................................................... 37 B. Aluminum Production .................................................... 38 1. Introduction ....................................................... 38 2. Electrolytic Reduction ............................................ 38 a. Pre bake Anode Process .................................... 38 b. Soderberg Anode Process ................................. 40 C. Iron and Steel Works ..................................................... 41 1. Iron Production ................................................... 41 2. Steel Production .................................................. 41 D. Iron and Steel Founding .................................................. 42 E. Petroleum Processing ..................................................... 43 F. Coal Conversion .......................................................... 43 1. Coal Gasification ................................................. 45 a. Historical Perspectives .................................... 45 b. Modem Coal Gasification Processes ....................... 45 c. Commercial Gasifiers ..................................... 46 d. Experimental Gasifiers .................................... 46 2. Coal Liquefaction ................................................. 47 G. Shale Oil Production ..................................................... 47 H. Asphalt Production and Use .............................................. 48 I. Carbon Black Production ................................................. 50 J. Combustion Engines ...................................................... 53 K. Lubricants ................................................................ 53 II. Pathways of Exposure ........................................................... 54 III. Summary and Conclusion ........................................................ 55 References ............................................................................... 55 Chapter 5 Sampling of PAH in Work Atmospheres .............................................. 57 I. Filter Sampling .................................................................. 57 II. Sampling by Filter and Back-Up ................................................. 58 III. Sampling Modes ................................................................. 59 A. Stationary Sampling ...................................................... 59 B. Personal Sampling ........................................................ 60 IV. Storage and Shipment. ........................................................... 61 V. Summary and Conclusions ....................................................... 61 References ............................................................................... 62 Chapter 6 Analytical Methods for Airborne PAH ................................................ 63 I. Real-Time Techniques ........................................................... 63 II. Fast and Inexpensive Group- or Compound-Specific Methods ................... 66 III. Detailed Analysis ................................................................ 71 A. Desorption ................................................................ 72 B. Isolation .................................................................. 74 1. Liquid-Liquid Partition ............................................ 74 2. Column Chromatography ......................................... 76 3. High-Performance Liquid Chromatography (HPLC) .............. 77 4. Thin-Layer Chromatography (TLC) ............................... 77 5. Selected Analytical Schemes ...................................... 78 C. Identification and Quantification ......................................... 79 I. TLC .............................................................. 79 2. HPLC ............................................................. 81 3. GC ................................................................ 85 IV. Quality Control of the Analytical Method ........................................ 90 A. Use of Internal Standards ................................................. 90 B. Intra- and Interlaboratory Control of PAH Analyses ...................... 90 V. Summary and Conclusion ........................................................ 94 References ............................................................................... 95 Chapter 7 Biological Monitoring of P AH Exposure ............................................. I 03 I. Intake, Distribution, and Excretion of PAH ..................................... I 03 II. Metabolism and Activation of PAH ............................................. 105 III. Effects of Particulate P AH ...................................................... 107 IV. Analysis of PAH in Urine ...................................................... I 08 V. Analysis of P AH in Blood Samples ............................................. Ill VI. Summary and Conclusion ....................................................... 113 References .............................................................................. 114 Chapter 8 PAH in Different Workplace Atmospheres .......................................... 117 I. Threshold Limit Values for PAH ............................................... 117 II. Gas Works and Coke Ovens .................................................... 118 Ill. Aluminum Plants ............................................................... 122 IV. Iron and Steel Works ........................................................... 125 V. Foundries ....................................................................... 126 VI. Manufacturing of Carbon Electrodes ............................................ 128 VII. Roofing, Paving, and Insulating ................................................ 129 VIII. Coal Conversion Plants ......................................................... 131 A. Coal Gasification Plants ................................................. 131 B. Coal Liquefaction Plants ................................................ 132 IX. Chimney Sweeping ............................................................. 133 X. Exposure to Exhaust from Combustion Engines ................................ 135 XI. Summary and Conclusion ....................................................... 136 References .............................................................................. 13 7 Chapter 9 PAH Profiles and Proxy Methods .................................................... 141 References .............................................................................. 144 Chapter 10 Methods of Analysis ................................................................... 147 I. Introduction ..................................................................... 147 II. Cyclohexane-Soluble Fraction of Total Particulate Matter ...................... 147 A. Scope and Field of the Application ...................................... 147 B. Principle ................................................................. 147 C. Apparatus ............................................................... 14 7 D. Reagents ................................................................. 148 E. Procedure ................................................................ 148 F. Calculations ............................................................. 148 G. Repeatability and Reproducibility ....................................... 149 H. Schematic Presentation of Procedure .................................... 149 I. Advantages and Disadvantages .......................................... 149 Ill. Analysis of BaP ................................................................. 149 A. Scope and Field of Application .......................................... 149 B. Principle ................................................................. 149 C. Apparatus ............................................................... 150 D. Reagents ................................................................. 151 E. Procedure ................................................................ 151 F. Calculation .............................................................. 152 G. Repeatability and Reproducibility ....................................... 152 H. Schematic Presentation of the Procedure ................................ 152 I. Advantages and Disadvantages .......................................... 152 IV. Gas Chromatographic Profile Analysis of PAH ................................. 152 A. Scope and Field of Application .......................................... 152 B. Principle ................................................................. 153 C. Apparatus ............................................................... 153 D. Reagents ................................................................. 153 E. Procedure ................................................................ 153 F. Calculation .............................................................. 155 G. Repeatability and Reproducibility ....................................... 156 H. Schematic Representative of the Procedure .............................. 157 I. Advantages and Disadvantages .......................................... 157 V. HPLC Determination of P AH ................................................... 157 A. Scope and Field of Application .......................................... 157 B. Principle ................................................................. 157 C. Apparatus ............................................................... 157 D. Reagents ................................................................. 158 E. Procedure ................................................................ 158 F. Calculations ............................................................. 159 G. Repeatability and Reproducibility ....................................... 159 H. Schematic Representation of the Procedure .............................. 160 I. Advantages and Disadvantages .......................................... 160 References .............................................................................. 160 Index ................................................................................... 163 1 Chapter I PAH AS OCCUPATIONAL CARCINOGENS I. HISTORICAL REVIEW The history of the detection, synthesis, and biological study of polycyclic aromatic hy drocarbons (PAH) is closely related to the establishment of the carcinogenicity of coal tar. Already in 1775, the British surgeon Sir Percivall Pott published studies which indicated increased incidences of scrotal cancer among chimney sweeps in England, resulting from prolonged contact of the skin with coal soot. 1 These chimney sweeps were, as children, forced to climb the narrow English chimneys and remove soot from the inside of the chimney flue. Dr. Pott assumed that the cause of the cancer development was soot and tar. It is, in retrospect, interesting to note that Dr. Pott did not regard scrotal cancer as a serious problem, since it could be removed without the least inconvenience. This part of Dr. Pott's observations is probably not valid today. About 100 years later, high incidences of skin cancer were reported among workers in the paraffin refining/ shale oil,1 and coal tar industries.'' However, early attempts to produce cancer in experimental animals with the raw materials of these industries were unsuccessful. It was not until 1915 that the Japanese pathologist Yamagiwa and his colleagues at the Imperial University of Tokyo' succeeded in inducing tumors with coal tar. Professor Ya magiwa and his assistant Ichikawa showed5 that if they repeatedly painted the inside of the cars of rabbits (two to three times a week), malignant tumors developed at the site of the skin painting after 3 months, and these later proved to be cancer tumors which grew over the whole ear. This was the first time that cancer tumors were produced experimentally by means of chemicals. It is interesting to note that Yamagiwa and Ichikawa made a very good choice by painting the cars of rabbits, since these show very high sensitivity toward exper imental carcinogens. If they had painted the skin of dogs or guinea pigs instead of rabbits, they probably would not have found any tumor development. Soon thereafter, Tsutsui" obtained malignant skin tumors in mice also by painting them with coal tar. This was the first experiment with a design that later should prove to be one of the most-used animal models for studies of carcinogenic compounds: skin painting on mice. Following Tsutsui's observation, other scientists showed that soot could be extracted and that these extracts also produced skin cancer on mice. Therefore, by 1925 it was well established that coal, tar, and soot contained material that was carcinogenic both to animals and to man. In the 19th century, a discovery was also made which was of basic importance to the chemical understanding of PAH. The recognition in 1865 that carbon atoms could be linked in closed rings was one of the great conceptual advances of chemistry. The discovery was made by August Kekule. 7 It is said that he solved the riddle of the structure of the benzene molecule after having a dream in which dancing snakes bit their own tails. From the understanding of the structure of the benzene molecule it was only a short step to the recognition that the naphthalene molecule has two fused benzene rings. The structure of the multiple-ring, or polycyclic compounds will be discussed below. Soon after Kekule's discovery, the classical paper of Berthelot was published" in which he showed that the heating of acetylene formed a tar which contained benzene and other aromatic hydrocarbons. A likely source of the PAH was therefore recognized. After the animal studies had demonstrated the presence of carcinogenic compounds in coal tar, studies were undertaken to attempt to characterize the carcinogens in this material. All that was known then was that the carcinogenic compounds were concentrated in the high-bOiling fractions of the tar. Kennaway and his group at the (then) Research Institute