Heavy Metals in the Environment - Chapter 1 pot

Heavy Metals in the Environment edited by Bibudhendra Sarkar The Hospital for Sick Children and University of Toronto Toronto, Ontario, Canada MARCEL n DECKER MARCEL DEKKER, INC. NEW YORK • BASEL Copyright © 2002 Marcel Dekker, Inc. ISBN: 0-8247-0630-7 This book is printed on acid-free paper. Headquarters Marcel Dekker, Inc. 270 Madison Avenue, New York, NY 10016 tel: 212-696-9000; fax: 212-685-4540 Eastern Hemisphere Distribution Marcel Dekker AG Hutgasse 4, Postfach 812, CH-4001 Basel, Switzerland tel: 41-61-261-8482; fax: 41-61-261-8896 World Wide Web http://www.dekker.com The publisher offers discounts on this book when ordered in bulk quantities. For more information, write to Special Sales/Professional Marketing at the headquarters address above. Copyright  2002 by Marcel Dekker, Inc. All Rights Reserved. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage and retrieval system, without permission in writing from the publisher. Current printing (last digit): 10987654321 PRINTED IN THE UNITED STATES OF AMERICA Copyright © 2002 Marcel Dekker, Inc. Preface Our global environment now consists of numerous natural and artificial metals. Metals have played a critical role in industrial development and technological advances. Most metals are not destroyed; indeed, they are accumulating at an accelerated pace, due to the ever-growing demands of modern society. A fine balance must be maintained between metals in the environment and human health. It is with this view in mind that this book has been written to address diverse issues surrounding heavy metals in the environment. Nineteen chapters have been contributed by 50 experts from around the world, known for their expertise and outstanding research. The book provides a critical review and analy- sis of the current state of knowledge of heavy metals in the environment. The volume begins with a chapter on the essentiality and toxicity of metals. The widespread distribution of metals in the environment is of great concern because of their toxic properties; however, some metals are also essential for normal growth and development. This chapter provides a critical assessment of nutritional and toxicological information based on available data on humans. The evaluation has used information available on speciation and bioavailability to identify the critical effects and clinical manifestations of metal deficiency and toxicity. New principles and basic concepts are presented to define the acceptable range of oral intake (AROI) at which no adverse effects occur and the correspond- ing safe range of population mean intake (SRPMI) of essential trace metals such as selenium, iron, manganese, zinc, and copper. The interdependence of various Copyright © 2002 Marcel Dekker, Inc. elements is discussed with regard to metabolic and functional interactions involv- ing storage and metabolism. Analytical measurements of heavy metals in the environment are an integral component of monitoring and assessing their toxic effects. They are required for regulatory purposes and routine monitoring to ensure compliance with allowed levels to determine hazardous conditions. Clean-ups of contaminated locations are commenced on the basis of measurements indicating the site and extent of contamination. Chapter 2, on analytical methods for quantitative determination of heavy metals discusses various analytical tools and speciation analyses of heavy metals as well as their microscopic analyses. Techniques used for specia- tion analyses are discussed for individual metals such as chromium, arsenic, mer- cury, lead, and cadmium. This chapter also describes recent developments in the use of microprobe beamline to monitor intracellular distribution of elements in a single cell. The need to develop and establish new toxicological approaches to assess the potential cytotoxic and genotoxic effects of heavy metals in the environment is addressed in Chapter 3, which focuses on a variety of in vitro toxicological screening methods for the biomonitoring of heavy metals. These methods take advantage of intracellular effects of metals to induce the expression of detoxify- ing proteins, other protective proteins, and proteins involved in cell cycles and proliferation and apoptosis. Suggestions are made as to the future of heavy metal biomarker research and how it can be more carefully monitored in the human environment. A large spectrum of radionuclides was produced after the creation of the cosmos. Their radioactive half-lives are very long, and they remain ubiquitous components of the environment. Additionally, as a result of the development of nuclear weapons and nuclear technology, a number of artificial radionuclides have become a part of the human environment. Chapter 4 discusses the distribu- tion and concentration of both natural and manmade radionuclides and the mecha- nism of their transfer to plants, animals, and humans. Possible long-term effects of their distribution in human tissue in terms of health implications are discussed. Metallic agents, as a class, make up a substantial portion of known human carcin- ogens. Chapter 5 reviews the topic of metal carcinogenesis, following the Interna- tional Agency for Research on Cancer (IARC) classification system, with particu- lar emphasis on known human carcinogens. In recent years, both carcinogenic and noncarcinogenic potential of arsenic have been intensely studied. Chapters 6 and 7 review the global perspective on arsenic in the environment and aspects of arsenic toxicity. Chapter 6 explores the environmental behavior of arsenic with special reference to the abundance and distribution of arsenic in the lithosphere, sediments, soil environment, and groundwater. It also discusses various pathways of arsenic emission into the envi- ronment, methods for arsenic determination in drinking water, and techniques Copyright © 2002 Marcel Dekker, Inc. for remediation of arsenic-contaminated soil and groundwater systems. Chapter 7 discusses the sources of human exposure and aspects of human toxicology with special emphasis on chronic arsenic poisoning and its general effects related to dermatological manifestations, cardiovascular diseases, neurological impair- ments, and cancer effects. Individual chapters are devoted to selected metals in the environment, in- cluding cadmium, chromium, aluminum, nickel, lead, mercury, and molybdenum. Chapter 8 reviews the pertinent literature of cadmium toxicology, with discus- sions of the health effects in humans of cadmium exposure and the molecular mechanisms underlying these effects. The connection between inhalation of chro- mium (VI) compounds and the causation of cancers of the airways and lungs is well established. Chapter 9 describes epidemiological studies along with the toxicokinetics and molecular mechanisms underlying the carcinogenicity of chro- mium (VI). It is followed by an in-depth consideration of approaches to the bio- logical monitoring of chromium (VI)–exposed subjects. Chapter 10 presents an assessment of the hazards of aluminum exposure to humans, animals, and plants. Chapter 11, on nickel, reviews its distributions in the environment, human expo- sure, metabolism, systemic and molecular toxicology, and carcinogenesis. This chapter also includes a discussion on the interaction of nickel with other essential metals such as magnesium, calcium, iron, zinc, and manganese. Chapter 12 dis- cusses the release of lead in the environment, human body burdens, and the popu- lation at risk. Special emphasis is given to analytical methods for the assessment of lead exposure and its metabolism, treatment of lead poisoning, in vitro and animal studies, molecular mechanisms, reproductive outcome, risk assessment and human epidemiological studies. It is believed that the global cycling of mercury of natural and anthropo- genic sources is responsible for the transport and deposition of mercury in areas remote from the original source. Chapter 13 takes a detailed look at mercury in the environment and its toxic actions, including a discussion on epidemiological studies of prenatal exposure. Molybdenum is essential to a variety of organisms, and is distributed widely in the environment owing to its diverse chemistry and its technological and agricultural applications. Chapter 14 provides a balanced picture of the complex environmental chemistry of molybdenum, including its interactions with copper, which can be either antagonistic or beneficial from the interplay of individual components in the biogeosphere. The intracellular concentration of heavy metals is kept in balance by a variety of metal-transporters. Many of the metals are toxic in excess. Bacterial metal resistance probably arose early in evolution owing to widespread geochem- ical sources of metals. Chapter 15, devoted to the microbial resistance mechanism of heavy metals, discusses the mechanisms of resistance to zinc, cadmium, lead, copper, arsenic, and antimony in bacteria. The exposure to metal that is harmless to some bacteria may be destructive to others with specific genetic changes. Chap- Copyright © 2002 Marcel Dekker, Inc. ter 16 examines genetic susceptibility to heavy metals in the environment, noting how each metal is expected to have its own series of transporters. Transport of several metals is highly dependent upon the concentration of the other metals. This balance can be disrupted when any gene within the balanced system is non- functional. The interaction between genes and environment—considered critical for avoiding metal toxicity not only for humans but also for a wide variety of animal species—is described in detail. Selenium has multiple biological actions as an essential trace element, a modifier of other toxic elements, an anticarcino- genic agent, and a toxicant. These are all discussed in Chapter 17, which provides an overview of the entire profile of biological actions of selenium in nutrition and toxicology. Over the past three decades, elements such as arsenic, antimony, gallium, and indium have been used in the manufacture of semiconductors for computer chips, cellular telephones, and light-emitting diodes. Many tons of these elements have been incorporated into these devices, either as dopants for silicon-based computer chips or in higher-speed semiconductors, such as gallium arsenide and indium arsenide. With the increased demand for higher-speed devices, older de- vices have been discarded, generating a large stockpile of electronic equipment containing these elements known collectively as ‘‘e-waste.’’ This is a new phe- nomenon, and the magnitude of this growing problem has been recognized only recently, since there are no well-established recycling programs for such item. Chapter 18, on semiconductors, provides an assessment of the present state of knowledge of the role and biological effects of metal/metalloids utilized in the semiconductor industry. The potential human health and environmental effects of these elements, either alone or as mixtures, are discussed in relation to areas of future studies. There is a growing need for methods of assessing the amount of heavy metals pollution in our natural and industrial environments. While it is relatively straightforward to use the techniques of analytical chemistry to detect heavy metal concentrations in a particular location, they do not indicate how much of this metal is a ‘‘biological hazard.’’ Chapter 19 describes biosensors for monitor- ing heavy metals, and how researchers are exploiting various biological mecha- nisms to determine the amount of ‘‘bioavailable’’ heavy metal in the natural and industrial environments. These methods are still in their infancy compared with the techniques of analytical chemistry, but they clearly offer advantages in terms of ease of use, and biological relevance. The recent progress made in the develop- ment of whole-cell and protein-based biosensors is encouraging and holds much promise for the future. The book was written by contributors in close collaboration with me. I visited some of their laboratories, intensively discussed their work with them, and made a few field trips to environmentally affected areas to obtain first-hand knowledge. Despite conscientious efforts by all concerned, the chapter authors, Copyright © 2002 Marcel Dekker, Inc. the editor, and the publisher cannot assume any liability for errors that this book may contain. Every effort has been made to keep the error rate as low as possible. Heavy Metals in the Environment will be an invaluable resource for toxicol- ogists; biochemists; bioinorganic, inorganic, environmental, and medicinal chem- ists; immunologists; oncologists; physiologists; pharmacologists; geneticists; bacteriologists; molecular biologists; environmental scientists; and upper-level undergraduate and graduate students in these disciplines. I thank many of my international colleagues who provided valuable sugges- tions in the selection of topics and other advice. Special thanks are due to Loretta LeBlanc for preparing the manuscript and to Suree Narindrasorasak, Ping Yao, and Negah Fatemi for their assistance in the preparation of the index. Bibudhendra Sarkar Copyright © 2002 Marcel Dekker, Inc. Contents Preface Contributors 1.EssentialityandToxicityofMetals Gunnar F. Nordberg, Brittmarie Sandstro ¨ m, George Becking, Robert A. Goyer 2. Analytical Methods for Heavy Metals in the Environment: Quantitative Determination, Speciation, and Microscopic Analysis Richard Ortega 3. In Vitro Toxicological Assessment of Heavy Metals and IntracellularMechanismsofToxicity Wendy E. Parris and Khosrow Adeli 4.RadionuclidesintheEnvironment David M. Taylor 5.MetalCarcinogenesis Michael P. Waalkes Copyright © 2002 Marcel Dekker, Inc. 6.ArsenicintheEnvironment:AGlobalPerspective Prosun Bhattacharya, Gunnar Jacks, Seth H. Frisbie, Euan Smith, Ravendra Naidu, and Bibudhendra Sarkar 7.EnvironmentalAspectsofArsenicToxicity J. Thomas Hindmarsh, Charles O. Abernathy, Gregory R. Peters, and Ross F. McCurdy 8.Cadmium Monica Nordberg and Gunnar F. Nordberg 9.ChromiumandCancer Montserrat Casadevall and Andreas Kortenkamp 10.Aluminum John Savory, R. Bruce Martin, Othman Ghribi, and Mary M. Herman 11.Nickel Jessica E. Sutherland and Max Costa 12.Lead Emily F. Madden, Mary J. Sexton, Donald R. Smith, and Bruce A. Fowler 13.Mercury Thomas W. Clarkson 14.Molybdenum Edward I. Stiefel and Henry H. Murray 15. Microbial Resistance Mechanisms for Heavy Metals and Metalloids Mallika Ghosh and Barry P. Rosen 16.GeneticSusceptibilitytoHeavyMetalsintheEnvironment Diane W. Cox, Lara M. Cullen, and John R. Forbes 17.SeleniuminNutritionandToxicology Seiichiro Himeno and Nobumasa Imura Copyright © 2002 Marcel Dekker, Inc. 18.Semiconductors Bruce A. Fowler and Mary J. Sexton 19. Bacterial Metal-Responsive Elements and Their Use in BiosensorsforMonitoringofHeavyMetals Ibolya Bontidean, Elisabeth Cso ¨ regi, Philippe Corbisier, Jonathan R. Lloyd, and Nigel L. Brown Copyright © 2002 Marcel Dekker, Inc. [...]... range of intakes for nutrients (e.g., essential metals) that protects most of the healthy individuals in specified gender and life-stage population groups from the risk of adverse effects from low intakes (deficiency) or excess intakes (toxicity) In deriving the limits of the AROI, uncertainties in the data as well as the variability in the intakes of individuals within the group must be considered The lower... nutrients (19 ) leading to reduced availability Copper uptake in the gut is inhibited by high zinc intakes Both a direct interaction and an interaction mediated by metallothionein induction may explain this phenomenon It is well known that zinc can induce metallothionein synthesis in intestinal cells Such metallothionein may sequester copper, since copper has higher affinity to SH groups on metallothionein than... losses of the element via skin, kidney, and intestine with the addition of requirements for synthesis of new tissue in periods of growth, has been the basis for the estimates of zinc requirement in the WHO 19 96 report (6) This approach was originally used for estimates of protein requirements The obligatory losses are usually determined in balance studies at different intakes The principal problem in relation... metallothionein than zinc By this mechanism copper may be trapped in the intestinal mucosa, not reaching the systemic circulation to the same extent as in persons with normal zinc intake and therefore increasing susceptibility to copper deficiency The critical effects of zinc toxicity are considered to be related to induced copper deficiency (20) There are some studies in animals indicating a decrease of... (9) and zinc (10 ) In addition, gastrointestinal losses of trace elements can be increased due to diarrhea If the disease is not well controlled by exclusion of gluten from the diet, and/or the decreased uptake is not compensated by an increased intake of these elements, iron and/ or zinc deficiency may develop Increased urinary losses of zinc are observed in patients with alcoholic cirrhosis (11 ) and... probability that the individual’s requirement was not met The WHO 19 96 report is concerned with population (group) mean intakes rather than intakes of individuals The lower limit of population mean intake is set so that very few individuals in the population (group) would be expected to have intakes below their requirement; i.e., the population mean intake corresponds to the estimates of average individual... metals, for example zinc Developmental abnormalities of the nervous system have also been shown in experimental animals as reviewed by Sandstead (16 ) In infancy, gastrointestinal absorption may be higher, that is, less well regulated, than in later stages of life In the elderly, intestinal uptake of trace metals may decline even in those with normal health (17 ) There are also differences in nutritional requirements... element, assuming a normal distribution of intakes and the coefficient of variation of the intake distribution As for the AROI, it is assumed that where the intakes of a population are maintained within the SRPMI, the risks to individuals within the group from deficiency or toxicity will be extremely low More details on these methodologies can be found elsewhere (6,54–56) With the exception of the SRPMI... toxicokinetic and toxicodynamic information that may be available as well as all data describing the shape of the dose-response curve and related statistical uncertainty The use of toxicokinetic and toxicodynamic modeling with estimated interindividual variability in computing the dose-response curve for the critical effect has been advanced by Nordberg and Strangert ( 61 63) and by Nordberg (25) These... population mean intake was set at 400 µg/day, being 50% of the intake where biochemical signs of disturbances in selenium metabolism, in the form of a reduction of the ratio of selenium in plasma to that in erythrocytes, start to occur Clinical signs of selenosis are observed at and above intakes of 900 µg/day If the same interindividual variation in requirement as used for the zinc estimates (CV 12 .5%) were . 4, Postfach 812 , CH-40 01 Basel, Switzerland tel: 4 1- 6 1- 2 6 1- 8 482; fax: 4 1- 6 1- 2 6 1- 8 896 World Wide Web http://www.dekker.com The publisher offers discounts on this book when ordered in bulk quantities Marcel Dekker, Inc. ISBN: 0-8 24 7-0 63 0-7 This book is printed on acid-free paper. Headquarters Marcel Dekker, Inc. 270 Madison Avenue, New York, NY 10 016 tel: 21 2-6 9 6-9 000; fax: 21 2-6 8 5-4 540 Eastern. analy- sis of the current state of knowledge of heavy metals in the environment. The volume begins with a chapter on the essentiality and toxicity of metals. The widespread distribution of metals