Ecotoxicology A Comprehensive Treatment

Contents
Hierarchical Ecotoxicology
The Hierarchical Science of Ecotoxicology
 An Overarching Context of Hierarchical Ecotoxicology
 Reductionism vs. Holism Debate
 Requirements in the Science of Ecotoxicology
Organismal Ecotoxicology
The Organismal Ecotoxicology Context
 Organismal Ecotoxicology Defined
 The Value of the Organismal Ecotoxicology Vantage
Biochemistry of Toxicants
 DNA Modification
 Detoxification of Organic Compounds
 Metal Detoxification, Regulation, and Sequestration
 Stress Proteins and Proteotoxicity
 Oxidative Stress
 Enzyme Dysfunction
Heme Biosynthesis Inhibition
 Oxidative Phosphorylation Inhibition
 Narcosis
Cells and Tissues
 Cytotoxicity
 Genotoxicity
 Cancer
 Sequestration and Accumulation
Organs and Organ Systems
 General Integument
 Organs Associated with Gas Exchange
 Circulatory System
 Digestive System
 Liver and Analogous Organs of Invertebrates
 Excretory Organs
 Immune System
 Endocrine System
 Nervous, Sensory, and Motor-Related Organs and Systems
Physiology
 Ionic and Osmotic Regulation
 Acid–Base Regulation
 Respiration and General Metabolism
 Bioenergetics
 Plant-Related Processes
Bioaccumulation
 Uptake
 Biotransformation
 Elimination
Models of Bioaccumulation and Bioavailability
 Bioaccumulation
 Bioavailability
Lethal Effects
 Quantifying Lethality
 Lethality Prediction
Sublethal Effects
 General Categories of Effects
 Quantifying Sublethal Effects
Conclusion
 General
 Some Particularly Key Concepts
 Concluding Remarks
Population Ecotoxicology
The Population Ecotoxicology Context
 Population Ecotoxicology Defined
 The Need for Population Ecotoxicology
 Inferences within and between Biological Levels
Epidemiology: The Study of Disease in Populations
 Foundation Concepts and Metrics in Epidemiology
 Disease Association and Causation
 Infectious Disease and Toxicant-Exposed Populations
 Differences in Sensitivity within and among Populations
Toxicants and Simple Population Models
 Toxicants Effects on Population Size and Dynamics
 Fundamentals of Population Dynamics
 Population Stability
 Spatial Distributions of Individuals in Populations
Toxicants and Population Demographics
 Demography: Adding Individual Heterogeneity to Population Models
 Matrix Forms of Demographic Models
Phenogenetics of Exposed Populations
 Toxicants and the Principle of Allocation (Concept of Strategy)
 Developmental Stability in Populations
Population Genetics: Damage and Stochastic Dynamics of the Germ Line
Direct Damage to the Germ Line
 Indirect Change to the Germ Line
 Genetic Diversity and Evolutionary Potential
Population Genetics: Natural Selection
 Overview of Natural Selection
 Estimating Differential Fitness and Natural Selection
 Ecotoxicology’s Tradition of Tolerance
Conclusion
 Overview
 Some Particularly Key Concepts
 Concluding Remarks
Community Ecotoxicology
Introduction to Community Ecotoxicology
 Definitions—Community Ecology and Ecotoxicology
 Historical Perspective of Community Ecology and Ecotoxicology
 Are Communities More Than the Sum of Individual Populations?
 Communities within the Hierarchy of Biological Organization
 Contemporary Topics in Community Ecotoxicology
Biotic and Abiotic Factors that Regulate Communities
 Characterizing Community Structure and Organization
 Changes in Species Diversity and Composition along Environmental Gradients
 The Role of Keystone Species in Community Regulation
 The Role of Species Interactions in Community Ecology and Ecotoxicology
 Environmental Factors and Species Interactions
Biomonitoring and the Responses of Communities to Contaminants
 Biomonitoring and Biological Integrity
 Conventional Approaches
 Biomonitoring and Community-Level Assessments
 Development and Application of Rapid Bioassessment Protocols
 Regional Reference Conditions
 Integrated Assessments of Biological Integrity
 Limitations of Biomonitoring
Experimental Approaches in Community Ecology and Ecotoxicology
 Experimental Approaches in Basic Community Ecology
 Experimental Approaches in Community Ecotoxicology
 Microcosms and Mesocosms
 Whole Ecosystem Manipulations
 What is the Appropriate Experimental Approach for Community Ecotoxicology?
Application of Multimetric and Multivariate Approaches in Community Ecotoxicology
 Multimetric
 Multivariate Approaches
Disturbance Ecology and the Responses of Communities to Contaminants
 The Importance of Disturbance in Structuring Communities
 Community Stability and Species Diversity
 Relationship between Natural and Anthropogenic Disturbance
 Contemporary Hypotheses to Explain Community Responses to Anthropogenic Disturbance
 Biotic and Abiotic Factors that Influence Community Recovery
 Influence of Environmental Variability on Resistance and Resilience
 Quantifying the Effects of Compound Perturbations
Community Responses to Global and Atmospheric Stressors
 CO₂ and Climate Change
 Stratospheric Ozone Depletion
 Acid Deposition
 Interactions among Global Atmospheric Stressors
Effects of Contaminants on Trophic Structure and FoodWebs
Basic Principles of FoodWeb Ecology
Effects of Contaminants on Food Chains and FoodWeb Structure
Conclusions
 General
 Some Particularly Key Concepts
Ecosystem Ecotoxicology
 Introduction to Ecosystem Ecology and Ecotoxicology
 Background and Definitions
 Ecosystem Ecology and Ecotoxicology: A Historical Context
 Challenges to the Study of Whole Systems
 The Role of Ecosystem Theory
 Recent Developments in Ecosystem Science
 Ecosytem Ecotoxicology
 Links from Community to Ecosystem Ecotoxicology
Overview of Ecosystem Processes
 Bioenergetics and Energy Flow through Ecosytems
 Nutrient Cycling and Materials Flow through Ecosystems
 Decomposition and Organic Matter Processing
Descriptive Approaches for Assessing Ecosystem Responses to Contaminants
Descriptive Approaches in Aquatic Ecosystems
Terrestrial Ecosystems
The Use of Microcosms, Mesocosms, and Field Experiments to Assess Ecosystem Responses to Contaminants and Other Stressors
Microcosm and Mesocosm Experiments
 Whole Ecosystem Experiments
Patterns and Processes: The Relationship between Species Diversity and Ecosystem Function
Species Diversity and Ecosystem Function
The Relationship between Ecosystem Function and Ecosystem Services
 Future Research Directions and Implications of the Diversity–Ecosystem Function Relationship for Ecotoxicology
 Ecological Thresholds and the Diversity–Ecosystem Function Relationship
Fate and Transport of Contaminants in Ecosystems
Bioconcentration, Bioaccumulation, Biomagnification, and Food Chain Transfer
 Modeling Contaminant Movement in FoodWebs
 Ecological Influences on Food Chain Transport of Contaminants
Effects of Global Atmospheric Stressors on Ecosystem Processes
 Nitrogen Deposition and Acidification
 Ultraviolet Radiation
 Increased CO2 and Global Climate Change
 Interactions among Global Atmospheric Stressors
 
Ecotoxicology: A Comprehensive Treatment—Conclusion
Conclusion
 Overarching Issues
 Summary: Sapere Aude
Index

Biography

Michael C. Newman, William H. Clements

Reviewed by A. Russell Flegal, Department of Environmental Toxicology, University of California for The Limnology and Oceanography Bulletin Volume 17 (2) June 2008

 

 

.Ecotoxicology: A Comprehensive Treatment. CRC

Press. ISBN978-0-8493-3357-6 (hardcover) 852 p. US $139

Toxicology, University of California, Santa Cruz, 1156 High Street,

Santa Cruz, CA 95064, USA; [email protected]

Nearly three decades ago I received a call from a colleague who chaired a large, multi-disciplinary program at a premier research university. He told me that they had been authorized to hire an ecotoxicologist, and he wanted me to tell him how to describe the position for their search. He assumed that I would be able to provide him with that information because I was in the process of establishing our nascent Department of Environmental Toxicology at the University of California, Santa Cruz. Unfortunately, I had to tell him that I hadn’t really been able to come up with a good description of an ecotoxicologist, but that I hoped that he would find someone else who had – because we were also supposed to recruit an ecotoxicologist for our program. I mention this shared ignorance, because I now find myself in awe of the breadth and depth of the new book by Newman and Clements (2008), Ecotoxicology: A Comprehensive Treatment. As the book extensively details, ecotoxicology is a new and still evolving science that synthesizes the complex fields of ecology and toxicology – which are themselves both multi-disciplinary and inter-disciplinary sciences.

The book is simply the best that I have encountered in providing an integrative presentation of the vast amount of knowledge required to practice ecotoxicology. Moreover, the authors go to great lengths to provide both (1) an historic background of the evolution of the science to date and (2) comments, suggestions, and predictions on how the science will continue to evolve. Their orientation is evidenced by the book’s concluding paragraph, which states: "Ecotoxicology’s ambitious goals, immediate obligations to society, and unquestionable success in generating a rich information base have created the need for integration of information and explanations into a congruent whole…. We suggest that the Strongest Inference Possible approach is the most effective approach currently available." This conclusion is, of course, most fitting for a book that begins with an Overview in Chapter 2 that states, "Conceptual consilence is not an intellectual nicety: it is vital to the health of any science. Without consistency among theories and facts, there is no way for the ecotoxicologist to choose from among many the explanation for providing the best foundation for predicting pollutant effects." This excellent book is obviously the product of careful work by two recognized experts in the field. They appear comfortable providing their opinions and perspectives, in addition to the facts found in most textbooks. Their design is immediately evident in the Preface, where the authors state that the book "is intended to bridge a widening gap between ecotoxicology textbooks and technical books focused on specific ecotoxicological topics." As they then note, there are plenty of narrowly focused books on different aspects of ecotoxicology that are written for experts in those areas, and an increasing number of texts that "are often broad-brush treatments of the field of ecotoxicology". In contrast, their book is designed to provide greater depth than other texts on ecotoxciology, while still maintaining a focus on the paradigms and fundamental themes of the science. I found the orientation wonderfully refreshing, albeit challenging.

Each chapter begins with a brief overview and then immediately goes into a relatively rigorous discussion. While many terms are defined, others are not – with the assumption that the reader is familiar with the argot and methodologies of each topic. Fortunately, each chapter then ends with a summary of bullets that synthesize the critical points covered in the chapter. Each chapter also has a list of references that is remarkably current and comprehensive. Consequently, while there may be few individuals that are fully conversant, much less expert, in all of the disciplines covered in the thirty-six (36) chapters of the long (852 page) book, it systematically provides summaries of the important points of each chapter and a wealth of references for further reading on each subject. The book is further organized into six (6) sections. These are titled "Hierarchical Ecotoxicology," "Organismal Ecotoxicology," "Population Ecotoxicology," "Community Ecotoxicology," "Ecosystem Ecotoxicology," and "Ecotoxicology: A Comprehensive Treatment – Conclusion." As previously indicated, each of those sections contains chapters that provide relatively rigorous, albeit terse, discussions using the argot and methodologies practiced by experts in the diverse disciplines. But what is relatively unusual about the different chapters with widely different topics is that the authors continually show how all of the material connects, routinely referring to related material in preceding and succeeding chapters. As a result, the book is both comprehensive and integrative (e.g., a population ecotoxicologist can appreciate the importance of a molecular toxicologist for their research and vice versa). The first section on "Hierarchial Ecotoxicology" is short: only 1 chapter and 10 pages long. It begins with the definition of ecotoxicology by Newman and Unger (2003): "Ecotoxicology is the science of contaminants in the biosphere and their effects on constituents of the biosphere, including humans." The chapter then illustrates the "unfixed cause–effect-significance concatenation" scheme applied to hierarchical subjects (e.g., from molecules to the biosphere). For example, toxicity observed in an organism may be explained by a toxic effect at the lower, suborganismal level and may be significant at the higher, population level. Consequently, the science of ecotoxicology needs to extend from the molecular level to the ecosystem level. The second section on "Organismal Ecotoxicology" focuses on factors influencing toxicity from molecular to cellular to tissue to organismal levels. When appropriate, the impacts of that toxicology are briefly extended to population and community 64 and ecosystem levels. However, most of the discussion is on biochemical and physiological processes involved in the accumulation, distribution, metabolism, and elimination of toxicants in cells, tissues, and individuals. The basic concepts of toxicology (e.g., bioavailability and bioaccumulation, dose-response curves, acute and sublethal toxicity) are also presented in this section. The third section on "Population Ecotoxicology" shifts to more mathematical models used in population biology and epidemiology. As the authors note, regulatory efforts are now primarily designed to protect populations from pollutants, using knowledge primarily derived from autecological studies. This incongruity both justifies the importance of the preceding section on organismal ecotoxicology and establishes the need to develop the emerging field of population ecotoxicology. Consequently, the section begins with a discussion on inferences within and between biological levels (e.g., individuals and populations) and then extends to a discussion of disease in populations (epidemiology). This sequencing is followed by the development of models of populations and of the effect of pollutants on populations, including models of population genetics and the phenogenetics of exposed populations. Again, this section employs the vocabulary and analytical methodologies used by researchers in population ecotoxicology, which are markedly different than those used by researchers in organismal ecotoxicology – but the authors systematically show how the two areas of research are closely connected. The fourth section on "Community Ecotoxicology" is more closely connected to the preceding section, in terms of argot and methodologies. Those two sections, along with the subsequent section on ecosystem ecotoxicology are what I have - apparently mistakenly - believed defined the range of ecotoxicology. Community ecotoxicology is also what I believed - apparently correctly - a relatively new focus for studies on the impacts of pollutants. As pointed out by the authors, while toxic effects are best understood at the lower levels of biological organization (e.g., molecular, cellular, and organismal), the adverse effects of toxicants may occur at broader spatial and temporal levels at higher levels of organization (e.g., population, community, and ecosystem) which may have greater ecological impact. This hierarchical concept is illustrated with discussions of principal biotic and abiotic considerations of factors governing community composition, the effects of toxicants on communities, biomonitoring communities, experimental studies of toxicants in communities, and whole ecosystem manipulation. These assessments build on models presented in the previous section, as well as numerous models presented within chapters in this section and an entire chapter on the application of multimeric and multivariate approaches in community ecotoxicology. The section then concludes with numerous examples of anthropogenic perturbations on communities (e.g., climate change, ozone depletion, acid deposition, and food web disruption). Consequently, I was pleased with the structure and depth of this section. The fifth section on "Ecosystem Ecotoxicology" extrapolates the concepts and methodologies of the preceding two sections to a more global scale. While the authors note that some ecologists consider ecosystems to be the fundamental units of nature, they concede that quantifying the effects of contaminants on ecosystems is extremely difficult – hence not routinely assessed. They then show the importance of global approaches to ecotoxicology, primarily though discussions on perturbations of biogeochemical cycles (e.g., C, N, P) and the resulting impacts on ecosystem productivity, composition, and health. There is also a chapter on the use of microcosms, mesocosms, and field experiments to assess ecosystem responses to stressors, including toxicants. After having been exposed to all of the terms and methods in the preceding sections, this section proved to be very easy to read and a wonderful conclusion to the book. However, there was yet another, sixth section on "Ecotoxicology: A Comprehensive Treatment – Conclusion," which I had no interest in reading but felt obligated to read for this review. Fortunately, the section consisted of a single (1), short (12 pages) chapter. And even better, the chapter was full of ideas and suggestions on how the science of ecotoxicology is evolving and how to optimize that evolution to benefit both science and society. The summary was essentially limited to the first paragraph of the chapter which stated that (1) the twin goals of differentiation and integration were presented in the first 35 chapters of the book and (2) "Facts and paradigms relevant to each level of the biological hierarchy were presented and then interconnected as much as presently possible." Then as previously indicated, the rest of the chapter provided metrics and concepts on what was needed for ecotoxicology to emerge as a "self-consistent science" and be of most value in addressing and resolving the increasingly complex and global environmental problems society now faces. While the brief concluding chapter could be the basis for an entire course, the utility of the book as the text for a course is more problematic. As I have repeatedly indicated – the book is quite long.

The authors state that the book is "designed to be flexible enough to meet a variety of instructional vantages, subsets of chapters may be used while de-emphasizing others," and they provide two examples of selected chapters for a 3-credit ecotoxicology course. They also suggest the entire book could be covered by a 4 credit course. However, I doubt that there are many faculty with the breadth and depth of expertise of the authors, who could teach the course. But I believe that the book would be ideal for a course that is team-taught by someone with an expertise in basic toxicology (i.e., molecular, cellular, and organismal toxicology) along with another person with an expertise in ecological toxicology (i.e., population, community, and ecosystem ecotoxicology). Alternatively, the course could be taught by an ecotoxicologist – now that I have a better understanding of what that job description entails. Some final comments. (1) The book is extremely well written. I specifically looked for flaws in science and composition, and I found few of either. (2) For such a long book, the wording is terse. Entire concepts and studies are presented in phrases. As a result, even reading short chapters can be exhausting. (3) Fortunately, the authors have gone to great lengths to provide both classic and new references to expand on the material covered in each chapter. (4) As the authors state in the final chapter, the book provides differentiation and integration of various aspects of ecotoxicology, and facts and paradigms of ecotoxicology are systematically presented and interconnected the text. In summary, it is - in my opinion - the definitive book to date on the complex and emerging science of ecotoxicology.