Radionuclide Concentrations in Foor and the Environment - Chapter 1 docx

DK594X_half 4/19/06 11:46 AM Page 1 Radionuclide Concentrations in Food and the Environment © 2007 by Taylor & Francis Group, LLC FOOD SCIENCE AND TECHNOLOGY Editorial Advisory Board Gustavo V. Barbosa-Cánovas Washington State University–Pullman P. Michael Davidson University of Tennessee–Knoxville Mark Dreher McNeil Nutritionals, New Brunswick, NJ Richard W. Hartel University of Wisconsin–Madison Lekh R. Juneja Taiyo Kagaku Company, Japan Marcus Karel Massachusetts Institute of Technology Ronald G. Labbe University of Massachusetts–Amherst Daryl B. Lund University of Wisconsin–Madison David B. Min The Ohio State University Leo M. L. Nollet Hogeschool Gent, Belgium Seppo Salminen University of Turku, Finland John H. Thorngate III Allied Domecq Technical Services, Napa, CA Pieter Walstra Wageningen University, The Netherlands John R. Whitaker University of California–Davis Rickey Y. Yada University of Guelph, Canada DK594X_series.qxd 4/19/06 10:39 AM Page 1 © 2007 by Taylor & Francis Group, LLC DK594X_title 4/19/06 2:38 PM Page 1 Radionuclide Concentrations in Food and the Environment Edited by Michael Pöschl Leo M. L. Nollet CRC is an imprint of the Taylor & Francis Group, an informa business Boca Raton London New York © 2007 by Taylor & Francis Group, LLC CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2007 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed in the United States of America on acid-free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number-10: 0-8493-3594-9 (Hardcover) International Standard Book Number-13: 978-0-8493-3594-5 (Hardcover) This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. No part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright. com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC) 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. 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 Nollet, Leo M. L., 1948- Radionuclide concentrations in food and the environment / Leo M.L. Nollet and Michael Poschl. p. cm. Includes bibliographical references and index. ISBN 0-8493-3594-9 (9780849335945 : alk. paper) 1. Radioactive pollution. 2. Radioactive contamination of food. I. Poschl, Michael. II. Title. TD196.R3N65 2006 363.17’992 dc22 2006003723 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com T&F_LOC_G_Master.indd 1 6/19/06 9:41:11 AM © 2007 by Taylor & Francis Group, LLC Preface The environment that surrounds us contains small amounts of radioactive (unstable) elements or radionuclides (radioisotopes) that are derived from primordial and secondary cosmogenic sources. In addition to naturally occurring radioactive materials (NORMs), technologically enhanced naturally occurring radioactive mate- rials (TENORMs) and man-made (artificially produced) radionuclides have been introduced into ecosystems due to the proliferation of different nuclear applica- tions in industry, medicine, and research. Radionuclides in the air, soil, water, and rocks that make up Earth’s geosphere and atmosphere can be transferred into the biosphere by many organisms and can also bioaccumulate in the food chain. This can result in an increase in population radiation doses, which requires an understanding of the environmental behaviors of different radionuclides and estimation of their human risks. This new radioecologically concerned publication on Radionuclide Concen- trations in Foods and the Environment addresses the key aspects of important and complex interdisciplinary issues concerning the relationship between natural and man-made sources of environmental radioactivity and the subsequent radio- nuclide concentrations in foods on an academic research level. It discusses the negative effects of environmental radioactivity on plants and animals, as well as the effects of radiocontaminated food on human health. It also offers perspectives for preventing the transfer of contaminants into foodstuffs and food raw materials. In Chapter 1, fundamental data for understanding the substance of matter and its behavior patterns are presented. A history of the atom and radioactivity, and important information about basic radiological terms as the basic properties of radionuclides are also outlined. A great deal of the book is devoted to the sources of radionuclides and the radionuclide content of the principal environmental components related to food production (soil and aquatic environments), as well as foodstuffs and food raw materials. Chapter 2 deals with the natural and anthropogenic (more accurately, primordial) sources of radionuclides found in the environment. It focuses on isotopic species that are important contributors to overall radionuclide abundances in various ecosystems. Air radionuclides can be easily transported throughout the environment and become part of food, contributing to the total radiation exposure of biota, includ- ing human beings. The origins and characteristics of these radionuclides are analyzed in Chapter 3. Special attention is paid to man-made radionuclides released into the air from nuclear weapons testing and production, electricity generation in nuclear power plants, and nuclear accidents. DK594X_book.fm Page v Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC Water covers more than two thirds of the Earth’s surface and is a necessary resource for human life: water is used for direct consumption, in the production of food, for many industrial activities, etc. Water is also a medium for the transport and interaction of radionuclides in different parts of the troposphere. Thus the radioactivity present in water can reach humans and ecosystems through many different mechanisms. These mechanisms are discussed in Chapter 4. Chapter 5 discusses the behavior of radionuclides in soil, including the frac- tionation of radionuclides in soils, radionuclide migration along the soil profile, the role of microorganisms, and radionuclide bioavailability and transference into plants. Finally, some scientific and social applications of radionuclide concentra- tion measurements in soils, such as dose assessment, earthquake prediction through radon measurements, and dating of a soil core, are discussed. The transfer/transport of radionuclides through ecosystems is discussed in Chapter 6, with and emphasis on their transport from the environment into food raw materials and foodstuffs. Predictive modeling of these transfer processes is analyzed and clarified. The physical and chemical aspects of ionizing radiation interactions and the biological consequences of radiation interactions (i.e., the effects of radioactivity on individual plants and animals), including information on the effects of radio- contaminated food on human health and further ecological consequences of radiation exposure are discussed in Chapter 7. In order to assess the impact of food contamination exposure on humans, radioactivity monitoring programs for food were developed, including interna- tional safety and trade legislation, and public reassurance. Both the possible content of radionuclides in foods and the importance of monitoring food for levels of radioactivity are discussed in Chapter 8. Characteristics of the pathways of radionuclide transfer from the environment to food and specification of radio- nuclides of interest in important food groups are discussed. Examples of special investigations and routine programs are also presented. Radiation detection and radioactivity analysis are the backbone of studies of environmental radioactivity as well as radionuclides in foods. These methods include techniques and principles that measure the disintegration rates of radio- nuclides and the types of radiation emanating from radioactive samples. Determin- ing the energies of emanating particles or electromagnetic (EM) rays originating in radioactive decay (radiospectrometry) provides a qualitative measure of radio- nuclides. Determining the disintegration rates thus provides a quantitative mea- sure of the amount of those radionuclides in the sample. Chapter 9 first focuses on the principles of radiation detection. Descriptions of the most used radiation detection and measurement systems and their main components follows. The precision and accuracy of radioactivity analysis of different environmental sam- ples are determined by high-quality sample preparation, calibration of the detec- tion system, quality control measures, and accurate radioactivity calculations. A good understanding of each of these aspects and practical experience are essential to performing accurate radioactivity analysis of foodstuffs and food raw materials. DK594X_book.fm Page vi Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC A radiation protection program is, in effect, a management system that affords organizations the ability to anticipate, recognize, evaluate, and control sources of radiation that might be present in the workplace. The main aim of such activities is to prevent or minimize the harmful effects of radiation sources. Many radio- active sources are used by human beings: as encapsulated standards for the calibration of counting equipment or in dispersible forms for radiolabeling or internal standardization procedures; in the form of radiation-producing devices such as analytical x-ray machines, electron microscopes, or x-ray diffraction devices. Samples of food and environmental media contain myriad radionuclides in various concentrations stemming from natural sources or from environmental releases. With all of these different types of sources that might be present in any analytical lab, and the various pathways for potential exposure, the development of a vigilant radiation protection program to protect the health of individuals associated with laboratory activities is considered a necessity. Safety management in radioanalytical laboratories is analyzed in Chapter 10. Ethnic, religious, social, political, and economic issues are causing complex conflicts in a number of critical regions of the world. One phenomenon of particular concern is the upsurge in global terrorist activity. A number of recent events show that terrorism is fast becoming a considerable threat to global secu- rity. While terrorist groups continue to use conventional weapons to conduct their operations, there is concern that some groups may be considering the use of radiological material. Relevant to this discussion are both nuclear (fissionable) and other radioactive materials, which, although disparate in terms of their poten- tial to cause destruction, are of increasing concern to the worldwide community. Chapter 11 discusses and analyzes many issues: the nuclear and radiological terrorist threat, the categorization of nuclear and radiological materials, radiolog- ical scenarios, the illicit trafficking of radioactive materials, the role of scientific practitioners, radiation detection strategies (radionuclides and radiation detection systems of interest in border monitoring), masking of illicit materials, nuclear and radiological forensics, and a number of other subjects related to protection against the radiological terrorist threat. The countermeasures limiting or preventing radiocontamination of plants and animals, which are the sources of plant- and animal-based foodstuffs, and which could also be the source of food contamination, are characterized in Chapter 12. International and national bodies have formulated maximum permissible contam- ination limits in response to the 1986 Chernobyl accident, and more recently in preparation for future radiological emergencies, either accidental or by malevolent intent. Individual countries have promulgated sets of regulatory limits, some based on international standards, some generated internally. To list control values for all countries would be impractical, therefore a limited selection of regulations and recommendations (relevant to radioactivity in food, the environment, and drinking water) from international agencies and some individual nations are presented. The radioactivity arising from naturally occurring radionuclides and man-made radioactive contamination are taken in the account in these regulations. DK594X_book.fm Page vii Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC The increasing consumer demand for “fresh” and natural food products has led to the improvement of nonthermal technologies such as irradiation and freez- ing as food preservation processes (Chapter 13). Nonthermal technologies, such as irradiation, have the ability to inactivate microorganisms at ambient or near- ambient temperatures, thus avoiding the deleterious effects of heat on flavor, color, and nutrient value. Irradiation has become one of the most extensively investigated and controversial technologies in food processing. For this reason, “food irradiation” is discussed in this book. Experts have regularly evaluated studies on the safety and proprieties of irradiated foods and have concluded that the process and the resulting foods are safe. The World Health Organization (WHO) recently concluded on the basis of extensive scientific evidence that food irradiated to any dose appropriate to achieve the intended technological objective is both safe to consume and nutritionally adequate. The editors do not claim that this book is exhaustive in its coverage of all aspects concerning the topic of radionuclides in foods. We are, however, very grateful to all the authors for their contributions, expertise, and unwavering commitment to this project. We also gratefully acknowledge the support of Patri- cia Roberson and Susan B. Lee (project coordinators, Taylor & Francis Group LLC) for their assistance in the preparation of this book. The book was edited by two editors; however, the person who initiated the writing of this book is Leo M. L. Nollet, who made it possible for M. Pöschl to participate in the editing. To him, M. Pöschl wishes to express his sincere thanks, not only for being provided this opportunity, but also for the advice, recommen- dations, and experience he so willingly and unselfishly rendered. Finally, and above all, we thank our wives, Vera and Clara, for their support, understanding, and patience during our months-long activities as editors of this book—it is little compensation for all the time we could not devote to them. We also dedicate this book to our sons and daughters. Michael Pöschl and Leo M. L. Nollet DK594X_book.fm Page viii Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC About the Editors Michael Pöschl is associate professor of special animal husbandry in the Depart- ment of Radiobiology of Faculty of Agronomy at the Mendel University of Agriculture and Forestry (MUAF) in Brno, Czech Republic. His mean research interests are situated in the domain of radioecology, radio-spectrometry, and radio- contamination of foodstuffs. Dr. Pöschl is author or co-author of numerous scientific articles, abstracts, and presentations. He received the RNDr. (Degree of Doctor of Natural Sciences, Charles University in Prague, Czech Republic, 1976) and Ph.D. (1986) degrees in biology from the MUAF. Leo M. L. Nollet is a professor of biochemistry, aquatic ecology, and ecotoxi- cology in the Department of Engineering Sciences, Hogeschool Gent, Ghent, Belgium. His main research interests are in the areas of food analysis, chroma- tography, and analysis of environmental parameters. He is the author or coauthor of numerous articles, abstracts, and presentations, and is the editor of Handbook of Food Analysis , 2nd ed. (three volumes), Food Analysis by HPLC , 2nd ed., and Handbook of Water Analysis (all titles, Marcel Dekker, Inc.). He received his M.S. (1973) and Ph.D. (1978) degrees in biology from the Katholieke Universiteit Leuven, Leuven, Belgium. DK594X_book.fm Page ix Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC Contributors Juan Pedro Bolívar Dpto. Física Aplicada Universidad de Huelva Huelva, Spain Maria Luísa Botelho Nuclear and Technological Institute Sacavém, Portugal F. J. Bradley New York, New York Sandra Cabo Verde Nuclear and Technological Institute Sacavém, Portugal Peter Carny Abmerit Trnava, Slovakia M. A. Charlton Department of Environmental Health and Safety University of Texas Health Science Center at San Antonio San Antonio, Texas Mike Colella Institute of Materials and Engineering Science Australian Nuclear Science and Technology Organisation Menai, Australia Guillermo Manjón Collado Departamento de Física Aplicada II E.T.S. Arquitectura Sevilla, Spain Tony Dell Radiochemistry Unit Vet Lab Agency New Haw, Addlestone, Surrey, England R. J. Emery Department of Environmental Health and Safety University of Texas Health Science Center at Houston Houston, Texas Pascal Froidevaux Institut de Radiophysique Appliquée Lausanne, Switzerland Jeffrey S. Gaffney Environmental Research Division Argonne National Laboratory Argonne, Illinois Kathryn A. Higley Department of Nuclear Engineering and Radiation Health Physics Oregon State University Corvallis, Oregon Ashraf Khater Physics Department College of Science King Saud University Riyadh, Saudi Arabia Manuel García-León Departamento de Física Atómica Molecular y Nuclear Universidad de Sevilla Sevilla, Spain DK594X_book.fm Page xi Tuesday, June 6, 2006 9:53 AM © 2007 by Taylor & Francis Group, LLC [...]... Isotope .6 1. 4 Radionuclides 8 1. 4 .1 Natural Radionuclides .9 1. 4 .1. 1 Primordial Radionuclides 9 1. 4 .1. 2 Secondary Radionuclides 9 1. 4 .1. 3 Cosmogenic Radionuclides 10 1. 4.2 Artificially Produced Radionuclides .10 1. 4.2 .1 Radionuclides Produced by Nuclear Reactors .10 1. 4.2.2 Radionuclides Produced by Particle Accelerators 11 1. 4.2.3 Radionuclides Produced... 11 1. 5 Radioactivity 12 1. 5 .1 Fundamentals of Radioactivity 12 1. 5.2 Simple Radioactive Decay, Decay Constant, Half-Life, Activity 13 1. 5.3 Radioactive Decay Chain 14 1. 5.4 Types of Radioactive Decay 14 1. 5.4 .1 Alpha Decay 14 1. 5.4.2 Beta Decay 15 1. 5.4.3 Electron Capture .15 1. 5.4.4 Gamma Emission and Isomeric Transition 16 1. 5.5 Interactions... 1. 5.5 Interactions of Radiation with Matter 16 1. 5.5 .1 Interactions of α Particles .17 1. 5.5.2 Interactions of β Particles .17 1. 5.5.3 Gamma Ray Interactions with Atoms 17 1. 6 Radionuclides Today 18 1. 6 .1 Radionuclides and Radioactivity: Uses .18 1. 6.2 Radionuclides and the Environment: Dangers 19 References 21 1 © 2007 by Taylor & Francis Group, LLC DK594X_book.fm... 60 days 8.04 days 5.3 days 30 years 74.2 days 73 hours 16 02 years 1. 41 × 10 10 years 7 .1 × 10 8 years 4. 51 × 10 9 years 2.44 × 10 4 years 458 years 2.65 years EC β+, EC IT EC β– β– IT EC EC EC β– β– β– β–, EC EC α α α α α α α, SF 3 H C 14 18 32 Ga Ga 81mKr 81Rb 90Y 99Mo 99mTc 11 1In 12 3I 12 5I 13 1I 13 3Xe 13 7Cs 19 2Ir 201Tl 226Ra 232Th 235U 238U 239Pu 241Am 252Cf 68 Application Biology, ecology Biology, ecology,... radioactive or they decay by electron capture; according to the mode of production, they are sometimes indicated as cyclotron radionuclides Some reactions of radionuclide production are 18 O(p,n )18 F, 13 C(p,n )13 N, 11 B(p,n )11 C, 10 B(d,n )11 C, and 56Fe(d,n)57Co 1. 4.2.3 Radionuclides Produced by Generators Radionuclide generators are used to obtain radionuclides with shorter half-lives from primary parent radionuclides... or very small mass The energy spectrum of β radiation is continuous The principle of β decay is the decay of nucleons in the nucleus, that is, of neutrons into protons and vice versa according to the following: 1 0 n  1 p + −0 e + νe , or 1 1 1 1 p  0 n + +0 e + νe 1 1 The β particles emitted by the nucleus in β decay (β emission) are fast moving (about 280,000 km/s) and high-energy particles... radioiodine 12 5I is used for in vitro radioimmunoassays (RIAs) More powerful sources (especially 60Co) γ rays or β particles are used in radiotherapy, including brachytherapy, immunotherapy, ion beam therapy, and boron neutron capture therapy Industrially and in mining, radionuclides are used as radioisotope tracers, in radiography and gauging, and in radiation processing to examine welds, detect leaks, and. .. 1. 3) In the following sections, the origin and nature of radionuclides (Section 1. 4) and radioactive decay or radioactivity as the basic properties of radionuclides (Section 1. 5) are described The recent importance of radionuclides is discussed in Section 1. 6, including their use and their health risks Since the history of radionuclides is immediately connected with our understanding of matter, and thus... categories according to their origin and formation: primordial radionuclides, secondary radionuclides, and cosmogenic radionuclides [12 ] 1. 4 .1. 1 Primordial Radionuclides Primordial radionuclides are radionuclides that originated with other (stable) nuclei in the course of cosmic nucleogenesis by thermonuclear reactions in the core of a star, which then exploded as a supernova and enriched the nucleus cloud... Some radionuclides (e.g., the uranium group) can be directly applied in human activities and, at the same time, they are much-feared products of nuclear power engineering The most frequently used radionuclides and their characteristics are shown in Table 1. 1 1. 6.2 RADIONUCLIDES AND THE ENVIRONMENT: DANGERS When ionizing radiation passes through matter, the component atoms may be ionized or excited In the . acid-free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number -1 0 : 0-8 49 3-3 59 4-9 (Hardcover) International Standard Book Number -1 3 : 97 8-0 -8 49 3-3 59 4-5 (Hardcover) This book contains information. Isotope 6 1. 4 Radionuclides 8 1. 4 .1 Natural Radionuclides 9 1. 4 .1. 1 Primordial Radionuclides 9 1. 4 .1. 2 Secondary Radionuclides 9 1. 4 .1. 3 Cosmogenic Radionuclides 10 1. 4.2 Artificially Produced Radionuclides. Ray Interactions with Atoms 17 1. 6 Radionuclides Today 18 1. 6 .1 Radionuclides and Radioactivity: Uses 18 1. 6.2 Radionuclides and the Environment: Dangers 19 References 21 DK594X_book.fm Page 1