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Biological degradation and bioremediation of toxic chemicals
232
Book Reviews
easy to read, with copious useful illustrations and very helpful summaries in boxes of the key issues. Each chapter ends with a pair of alternative hypotheses concerning impacts of the accident, followed by appropriate research recommendations. Chapter 1 describes the Chernobyl accident and its immediate consequences, emphasising how Belorus caught the brunt of the deposition, but surprisingly fails to mention its causes, which were an appalling and fatal combination of design fault and human error. The next chapter is concerned with impacts on natural ecosystems, with some fascinating descriptions of growth abnormalities on the forest flora. This concentrates largely on the sensitivity of different plant and animal species to radioactivity, but says relatively little about the cycling of radionuclides in forests, which has attracted such intense research interest over the last 10 years. Chapter 3 is concerned with agro-ecosystems, in particular transfers of radionuclides between soils, crops and domestic animals, and the countermeasures introduced to reduce dose to humans. I was intrigued to note the progressive reduction in ‘temporary permissible’ levels in food stuffs down to present ‘control’ levels, which in the case of meat are well below the 1000 Bq kg-’ limit imposed on sheep after Chernobyl deposition in the United Kingdom. The next chapter is entitled ‘Human Ecology’ and is concerned with health impacts of the accident, indicating that these result from both chemical and radiotoxicity, and are by no means restricted to cancers. Chapter 5 covers ‘Biological Diversity’ and is most disappointing, with eighteen pages of basic genetics and phenetics, followed by only four on what actually happened in this respect in heavily contaminated areas, and even these largely consist of photographs. The following chapter can be criticised on the same grounds, as it goes to great lengths in describing the role of mutations in changing population characteristics but contains only three pages on the role of radioactivity in this respect, although there is a fascinating description of the results of screening of Chernobyl-affected humans for cytogenetic damage. Chapter 7 on socio-economic systems starts with a rather ‘woolly’ preamble on sustainable development and ecological economics, but subsequently develops into an interesting description of the response of the Soviet authorities and their successors. Emphasis is given not only to the phenomenal economic consequences of the accident for Belorus, Ukraine and Russia, but also ‘human’ costs such as increased divorce rates in affected areas. It concludes with a description of the international action which resulted in the setting up of the Chernobyl Centre for International Research. This leads into the final part of the book which describes in detail the establishment of the Chernobyl Ecological Science Network and its future research themes. The rather specialised discipline of radioecology received an unexpected and unprecedented boost after Chernobyl, particularly in relation to the behaviour of radionuclides in non-agricultural ecosystems. I had
anticipated to read far more about these activities from the perspective of scientists directly involved with research in the most heavily contaminated areas, but my expectaions were not fulfilled. J. N. B. Bell
Biological Degradation and Bioremediation of Toxic Chemicals. Edited by G. Rasul Chaudhry. Chapman
and Hall, London, g50.00.
1995, ISBN o-412-62290-4. Price:
Nearly 50 years ago, the word ‘biodegradation’ and its derivatives entered the language and today it is well defined and common place. In the last few years a new word, ‘bioremediation’, has come along to fill a need to describe ‘new’ concepts/processes, though bioremedial processes have been practised perhaps unwittingly for centuries. Discussing definitions can be stifling or enlightening; in the present case it seems worthwhile. The personal definition of bioremediation in the preface to this book is wide and all-embracing, namely, ‘to cure, to restore, to correct or to repair, by biological processes, what we have done to hurt our environment and ecosystems;’ and it is equated to ‘environmental technology’. Thus, it includes the various forms of sewage waste water treatment systems which other definitions would exclude on the grounds that such systems are protective or preventative, or ‘bioprophylattic’. Such an attitude would restrict the term bioremediation to the restoration of contaminated soils, ground water or even gases, focusing on enhancing existing, but slow, biodegradation processes. Also, it is not the toxic chemical which is remedied; it is rather. the problems caused by the presence of the chemical which are remedied. However, the book takes the wider view as witnessed by the references to waste water treatment, e.g. in the case of morpholine. What is expected from a book with the above title is, for each chemical or class of chemicals, a description of the source of the competent species of micro-organisms, including how to adapt or genetically engineer suitable species; their nutrition and physiology; and other factors which would assist in deciding whether and how bioremediation could occur. Important questions to be answered are: would the (engineered) bacteria survive in the environment?; is a co-substrate necessary?; would the target substrate be degraded in the presence of other xenobiotic chemicals?; is there competition with indigenous species? Then would follow accounts of laboratory- and pilot-scale attempts at bioremediation and finally descriptions and results of full-scale trials. These expectations are not fulfilled in the book but reference to the introduction shows why-the book sets out to describe recent advances in the biodegradation of selected pollutants but then to describe only the potential applications to alleviate this pollution. With this proviso, the book does live up to its goal. In all
Book Reviews cases, the description of the search for competent species, or consortia, to carry out biodegradation (aerobic and, where possible, anaerobic) is at least adequate but mostly well done. Abundant literature citations are given and possible pitfalls in applying the reactions are highlighted. However, only about a quarter of the chapters give adequate consideration to potential bioremediation, one of the best being that for the desulphurization of coal. Another quarter gives less on bioremediation, while the remaining half say little or nothing. This presumably reflects the state of knowledge at the time of writing, around 1992. A very short chapter devoted to the practical aspects of bioremediation processes-composting, slurry reactors, above-site reactors, in situ ground water biorestoration--would have been helpful to the uninitiated. The book, which contains 23 chapters (19 originate from the USA or Canada, three from Europe and one from Japan), opens with two rather general chapters. The first gives an account of the immense potential of pseudomads for degrading xenobiotic aromatic compounds and the second is a detailed general discussion of the genetic systems in soil bacteria for the degradation of polychlorinated biphenyls (PCBs). The chemicals considered in the body of the book are mostly xenobiotics which are distributed throughout the environment. They include polycyclic aromatic hydrocarbons, many chlorinated compounds--PCBs, chlorinated phenols, hydrocarbons, acids, low molecular weight chlorinated aliphatics--as well as carbamates, thiocarbamates and organophosphorus pesticides. Other chemicals considered are aromatic carboxylates and sulphonates, munitions chemicals such as trinitrotoluene, and the relatively simple xenobiotic morpholine. There are two chapters on the intriguing, wide-spectrum, non-specific activities of lignin-degrading enzymes of white rot fungi and another on the microbial transformations of constituents of lignin-containing wastes. The book concludes with chapters on reactions carried out by entrapped or encapsulated micro-organisms, the detoxification of Cr 6÷ to Cr3÷,and two enlightening chapters on the bioprocessing of coal and its desulphurization. The choice of most chemicals was made for obvious reasons; the inclusion of chromium and coal was unexpected but interesting, while a chapter on morpholine was surprising but welcome, since it contrasted well with the intricacies of the degradation of chemicals such as PCBs. The plan behind the order of the chapters is not clear. For example, the long chapter reviewing the development of bacterial strains which degrade chloroaromatics would have been better placed near the beginning and the remaining chapters on chlorocompounds should have been placed closer together. For such a large book there are few typographical errors and the clear print on non-glossy paper (overcoming problems of reflection) is welcome, even if inclined to be old-fashioned. However, there are some difficulties with the presentation; some of the reaction
233
diagrams are unclear but most serious is the problem associated with the line width. At 14 cm, the print width made it difficult to take in the meaning of the text and was tiring on the eyes; 7 cm is probably ideal with a maximum of 10 cm. Also, the use of the book would have been greatly facilitated by having a list of contents (or sections) either at the front of the book or, preferably, at the beginning of each chapter--this would augment the index, which was found to be very helpful. This well-written book, full of information, will be of value not only to specialists in the field but also to senior undergraduates, postgraduates and researchers coming to the subject for the first time. As for the future of bioremediation, the prospect is bright because of the need and interest in the topic, and the rate at which relevant data are being acquired. In five years or so, a similar book might well be able to contain as much information on bioremediation involving a wide variety of chemicals as the present volume contains on biodegradation. H. A. Painter
Atmospheric Deposition in Relation to Acidification and Eutrophication (Studies in Environmental Science 63). By J. W. Erisman and G. P. J. Draaijers. Elsevier Science BV, Amsterdam, 1995, ISBN 0-44a,-82247-X, 442 pp. Price: US$161.75. The authors have first-hand knowledge of the current state of research into atmospheric deposition in The Netherlands and present recent findings from the extensive national research programmes in a wider context. Many of the most recent results have yet to appear in the open literature and are only available as internal reports. This volume provides an excellent introduction to, and summary of, the detailed studies conducted in The Netherlands over the past decade or so, while providing the necessary background information to supply the general reader with a framework for evaluating the results. Although aimed primarily at people already involved in acidification research, the style and content are such that the policy maker, student or interested non-specialist will find much of interest. The first chapter introduces the problems associated with acid deposition and defines some of the concepts to be used later, before embarking on a history of atmospheric deposition research over the past two centuries or more. This whistle-stop tour through history is laced with quotations and references to original papers, not all of which, unfortunately, are listed in the references at the end of the book. The study of atmospheric deposition is not about 'stamp collecting' more and more data with ever increasing precision, at smaller and smaller spatial scales---research has to provide a better understanding of
Book Reviews
easy to read, with copious useful illustrations and very helpful summaries in boxes of the key issues. Each chapter ends with a pair of alternative hypotheses concerning impacts of the accident, followed by appropriate research recommendations. Chapter 1 describes the Chernobyl accident and its immediate consequences, emphasising how Belorus caught the brunt of the deposition, but surprisingly fails to mention its causes, which were an appalling and fatal combination of design fault and human error. The next chapter is concerned with impacts on natural ecosystems, with some fascinating descriptions of growth abnormalities on the forest flora. This concentrates largely on the sensitivity of different plant and animal species to radioactivity, but says relatively little about the cycling of radionuclides in forests, which has attracted such intense research interest over the last 10 years. Chapter 3 is concerned with agro-ecosystems, in particular transfers of radionuclides between soils, crops and domestic animals, and the countermeasures introduced to reduce dose to humans. I was intrigued to note the progressive reduction in ‘temporary permissible’ levels in food stuffs down to present ‘control’ levels, which in the case of meat are well below the 1000 Bq kg-’ limit imposed on sheep after Chernobyl deposition in the United Kingdom. The next chapter is entitled ‘Human Ecology’ and is concerned with health impacts of the accident, indicating that these result from both chemical and radiotoxicity, and are by no means restricted to cancers. Chapter 5 covers ‘Biological Diversity’ and is most disappointing, with eighteen pages of basic genetics and phenetics, followed by only four on what actually happened in this respect in heavily contaminated areas, and even these largely consist of photographs. The following chapter can be criticised on the same grounds, as it goes to great lengths in describing the role of mutations in changing population characteristics but contains only three pages on the role of radioactivity in this respect, although there is a fascinating description of the results of screening of Chernobyl-affected humans for cytogenetic damage. Chapter 7 on socio-economic systems starts with a rather ‘woolly’ preamble on sustainable development and ecological economics, but subsequently develops into an interesting description of the response of the Soviet authorities and their successors. Emphasis is given not only to the phenomenal economic consequences of the accident for Belorus, Ukraine and Russia, but also ‘human’ costs such as increased divorce rates in affected areas. It concludes with a description of the international action which resulted in the setting up of the Chernobyl Centre for International Research. This leads into the final part of the book which describes in detail the establishment of the Chernobyl Ecological Science Network and its future research themes. The rather specialised discipline of radioecology received an unexpected and unprecedented boost after Chernobyl, particularly in relation to the behaviour of radionuclides in non-agricultural ecosystems. I had
anticipated to read far more about these activities from the perspective of scientists directly involved with research in the most heavily contaminated areas, but my expectaions were not fulfilled. J. N. B. Bell
Biological Degradation and Bioremediation of Toxic Chemicals. Edited by G. Rasul Chaudhry. Chapman
and Hall, London, g50.00.
1995, ISBN o-412-62290-4. Price:
Nearly 50 years ago, the word ‘biodegradation’ and its derivatives entered the language and today it is well defined and common place. In the last few years a new word, ‘bioremediation’, has come along to fill a need to describe ‘new’ concepts/processes, though bioremedial processes have been practised perhaps unwittingly for centuries. Discussing definitions can be stifling or enlightening; in the present case it seems worthwhile. The personal definition of bioremediation in the preface to this book is wide and all-embracing, namely, ‘to cure, to restore, to correct or to repair, by biological processes, what we have done to hurt our environment and ecosystems;’ and it is equated to ‘environmental technology’. Thus, it includes the various forms of sewage waste water treatment systems which other definitions would exclude on the grounds that such systems are protective or preventative, or ‘bioprophylattic’. Such an attitude would restrict the term bioremediation to the restoration of contaminated soils, ground water or even gases, focusing on enhancing existing, but slow, biodegradation processes. Also, it is not the toxic chemical which is remedied; it is rather. the problems caused by the presence of the chemical which are remedied. However, the book takes the wider view as witnessed by the references to waste water treatment, e.g. in the case of morpholine. What is expected from a book with the above title is, for each chemical or class of chemicals, a description of the source of the competent species of micro-organisms, including how to adapt or genetically engineer suitable species; their nutrition and physiology; and other factors which would assist in deciding whether and how bioremediation could occur. Important questions to be answered are: would the (engineered) bacteria survive in the environment?; is a co-substrate necessary?; would the target substrate be degraded in the presence of other xenobiotic chemicals?; is there competition with indigenous species? Then would follow accounts of laboratory- and pilot-scale attempts at bioremediation and finally descriptions and results of full-scale trials. These expectations are not fulfilled in the book but reference to the introduction shows why-the book sets out to describe recent advances in the biodegradation of selected pollutants but then to describe only the potential applications to alleviate this pollution. With this proviso, the book does live up to its goal. In all
Book Reviews cases, the description of the search for competent species, or consortia, to carry out biodegradation (aerobic and, where possible, anaerobic) is at least adequate but mostly well done. Abundant literature citations are given and possible pitfalls in applying the reactions are highlighted. However, only about a quarter of the chapters give adequate consideration to potential bioremediation, one of the best being that for the desulphurization of coal. Another quarter gives less on bioremediation, while the remaining half say little or nothing. This presumably reflects the state of knowledge at the time of writing, around 1992. A very short chapter devoted to the practical aspects of bioremediation processes-composting, slurry reactors, above-site reactors, in situ ground water biorestoration--would have been helpful to the uninitiated. The book, which contains 23 chapters (19 originate from the USA or Canada, three from Europe and one from Japan), opens with two rather general chapters. The first gives an account of the immense potential of pseudomads for degrading xenobiotic aromatic compounds and the second is a detailed general discussion of the genetic systems in soil bacteria for the degradation of polychlorinated biphenyls (PCBs). The chemicals considered in the body of the book are mostly xenobiotics which are distributed throughout the environment. They include polycyclic aromatic hydrocarbons, many chlorinated compounds--PCBs, chlorinated phenols, hydrocarbons, acids, low molecular weight chlorinated aliphatics--as well as carbamates, thiocarbamates and organophosphorus pesticides. Other chemicals considered are aromatic carboxylates and sulphonates, munitions chemicals such as trinitrotoluene, and the relatively simple xenobiotic morpholine. There are two chapters on the intriguing, wide-spectrum, non-specific activities of lignin-degrading enzymes of white rot fungi and another on the microbial transformations of constituents of lignin-containing wastes. The book concludes with chapters on reactions carried out by entrapped or encapsulated micro-organisms, the detoxification of Cr 6÷ to Cr3÷,and two enlightening chapters on the bioprocessing of coal and its desulphurization. The choice of most chemicals was made for obvious reasons; the inclusion of chromium and coal was unexpected but interesting, while a chapter on morpholine was surprising but welcome, since it contrasted well with the intricacies of the degradation of chemicals such as PCBs. The plan behind the order of the chapters is not clear. For example, the long chapter reviewing the development of bacterial strains which degrade chloroaromatics would have been better placed near the beginning and the remaining chapters on chlorocompounds should have been placed closer together. For such a large book there are few typographical errors and the clear print on non-glossy paper (overcoming problems of reflection) is welcome, even if inclined to be old-fashioned. However, there are some difficulties with the presentation; some of the reaction
233
diagrams are unclear but most serious is the problem associated with the line width. At 14 cm, the print width made it difficult to take in the meaning of the text and was tiring on the eyes; 7 cm is probably ideal with a maximum of 10 cm. Also, the use of the book would have been greatly facilitated by having a list of contents (or sections) either at the front of the book or, preferably, at the beginning of each chapter--this would augment the index, which was found to be very helpful. This well-written book, full of information, will be of value not only to specialists in the field but also to senior undergraduates, postgraduates and researchers coming to the subject for the first time. As for the future of bioremediation, the prospect is bright because of the need and interest in the topic, and the rate at which relevant data are being acquired. In five years or so, a similar book might well be able to contain as much information on bioremediation involving a wide variety of chemicals as the present volume contains on biodegradation. H. A. Painter
Atmospheric Deposition in Relation to Acidification and Eutrophication (Studies in Environmental Science 63). By J. W. Erisman and G. P. J. Draaijers. Elsevier Science BV, Amsterdam, 1995, ISBN 0-44a,-82247-X, 442 pp. Price: US$161.75. The authors have first-hand knowledge of the current state of research into atmospheric deposition in The Netherlands and present recent findings from the extensive national research programmes in a wider context. Many of the most recent results have yet to appear in the open literature and are only available as internal reports. This volume provides an excellent introduction to, and summary of, the detailed studies conducted in The Netherlands over the past decade or so, while providing the necessary background information to supply the general reader with a framework for evaluating the results. Although aimed primarily at people already involved in acidification research, the style and content are such that the policy maker, student or interested non-specialist will find much of interest. The first chapter introduces the problems associated with acid deposition and defines some of the concepts to be used later, before embarking on a history of atmospheric deposition research over the past two centuries or more. This whistle-stop tour through history is laced with quotations and references to original papers, not all of which, unfortunately, are listed in the references at the end of the book. The study of atmospheric deposition is not about 'stamp collecting' more and more data with ever increasing precision, at smaller and smaller spatial scales---research has to provide a better understanding of