1st Edition

Ecotoxicology Effects of Pollutants on the Natural Environment

By Colin Walker Copyright 2014
    233 Pages 40 B/W Illustrations
    by CRC Press

    Chemical Warfare in Nature

    Pesticides and other industrial chemicals are at the root of many pollution problems. In view of the toxic effects of industrial chemicals found in the water, soil, and air, Ecotoxicology: Effects of Pollutants on the Natural Environment considers the impact of chemicals on the environment from a wider perspective: the evolution of plant toxins—and defense mechanisms against them in animals as a consequence of plant–animal warfare. Comparisons are made between this and the development of resistance by insects towards man-made insecticides.

    Pesticides and Drugs

    The text focuses particularly on problems posed by pesticides and, to a lesser extent, by drugs. This material specifically addresses the problems that pesticides pose and explores the development of resistance to them. It focuses on the history of pesticides, pesticide selectivity between target species and beneficial organisms, and types of pesticides. It discusses mandatory ecotoxicity testing as part of the process of risk assessment of environmental chemicals. The text considers the effects of pollutants at the population level, with respect to changes in numbers and genetic composition. It factors in the sublethal effects of pollutants on population levels, and cites an increase in the concentration of persistent pollutants in natural food chains as a cause of the decline of certain vertebrate predators.

    Overall the text:

    • Considers plant toxins as models for pesticides

    • Emphasizes principles illustrated with practical examples

    • Includes a glossary of terms

    Divided into three sections, this text uses a variety of examples and case studies to examine the effects of pollutants—including naturally occurring ones—on natural processes. It guides the reader through the basic issues and principles; outlines the science of ecotoxicology, which is the study of the effects of chemicals upon ecosystems; and introduces various strategies for pollution control.

    Section I Basic Issues
    Toxicology and Ecotoxicology
    Some Definitions
    The Discipline of Ecotoxicology
    Selective Toxicity
    Further Reading
    What Determines Ecotoxicity?
    Pesticides and Other Biocides
    Industrial Chemicals Other Than Pesticides
    Protocols for Ecotoxicity Testing
    Determination of Median Lethal Dose and Median Lethal
    Ecotoxicity Testing That Uses Sublethal Endpoints
    Bioassays for Measuring Toxicity
    Model Ecosystems
    Ethical Issues
    Further Reading
    A History of Chemical Warfare
    An Evolutionary Perspective
    Plant Toxins as Pesticides
    The Coevolutionary "Arms Race"
    Plant Toxins as Models for Pesticides
    Chemical Weapons and Predation
    Chemical Weapons of Attack and Defense
    Microbial Toxins
    Ecotoxicology against the Background of Chemical Warfare in Nature
    Further Reading
    Toxic Effects at Different Organizational Levels
    Sequential Effects of Pollutants
    Effects upon the Individual Organism
    Effects at the Population Level
    Effects upon Population Genetics
    Communities and Ecosystems
    Effects upon Structure and Function of Communities and Ecosystems
    Monitoring Changes in the Composition of Communities
    Field Trials
    Further Reading
    The Development of Resistance
    Population Genetics and Evolutionary Theory
    Pollutants as Stress Factors
    Mechanisms of Resistance
    Overcoming Problems of Pesticide Resistance
    The Evolution of Metal Tolerance in Plants
    Resistance as an Indicator of Pollution
    Further reading
    Pesticides and Their Design
    Early History of Pesticides
    The Importance of Selectivity
    Types of Pesticides
    Ways of Using Pesticides
    Objectives in the Design of New Pesticides
    Mass Screening
    Modeling of New Pesticides Based upon the Structures of Sites of Action
    Further Reading
    Natural Pollutants and Natural Cycles
    Acid Rain
    Radiation and Radioisotopes
    Oil Pollution
    Greenhouse Gases and Global Warming
    The Ozone Layer
    Global Processes and the Gaia Theory
    Further Reading
    Section II Examples of Pollutants
    Early Problems Connected with Urbanization and Mining
    Detergents in Surface Waters
    Air Pollution
    Mines and Smelting
    Further Reading
    The Organochlorine Insecticides
    DDT and Related Pesticides
    The Environmental Fate of p,p’-DDT and Related Compounds
    The Cyclodiene Insecticides
    The Environmental Fate of Cyclodienes
    Effects of DDT and Cyclodienes on Birds of Prey
    Decline of Predatory Birds Related to Eggshell Thinning Caused by p,p’-DDE
    Other Effects of Organochlorines
    Resistance to Organochlorine Insecticides
    More Ecofriendly Cyclodienes
    Further Reading
    Organophosphorous and Carbamate Insecticides
    Mode of Action of Anticholinesterases
    The Organophosphorous Insecticides
    Some Examples of Organophosphorous Insecticides
    Toxic Effects of OPs
    Effects of OPs in the Natural Environment
    Resistance to OPs
    Carbamate Insecticides
    Toxicity of Carbamates in the Field
    Longer-Term Effects on Soil Microorganisms
    Further Reading
    Organometallic Compounds
    Tributyl Tin Compounds
    Organomercury Compounds
    The Biomagnification of Methylmercury
    Poisoning of Predatory Birds in the Field
    Methylmercury Levels in Piscivorous Vertebrates in North America
    Organolead Compounds
    Organoarsenic Compounds
    Further reading
    Pyrethroid and Neonicotinoid Insecticides
    The Synthetic Pyrethroids
    Environmental Fate and Concerns
    The Development of Resistance to Pyrethroids
    The Neonicotinoids
    Development of Resistance to Neonicotinoids
    Potentiation of the Toxicity of Pyrethroids and Neonicotinoids
    Effects of Pyrethroids and Neonicotinoids on Honeybees
    Further Reading
    PCBs and Dioxins
    The Polychlorinated Biphenyls (PCBs)
    Early Pollution Incidents Involving PCBs
    The Dioxins
    The Combined Toxicity of PCBs and Dioxins
    Further Reading
    The Impact of Herbicides on Agricultural Ecosystems
    The Aerial Movement of Herbicides
    Contamination of Surface Waters with Herbicides
    Herbicides That Have Significant Toxicity toward Animals
    Further Reading
    Endocrine Disruptors
    The Feminization of Fish Caused by Estrogens
    Endocrine Disruption Involving the Ah Receptor
    Disturbances of the Metabolism of Steroid Hormones by Pollutants
    The Diversity of Endocrine-Disrupting Chemicals (EDCs) in the Environment
    Further Reading
    Anticoagulant Rodenticides
    Mode of Action of the Anticoagulant Rodenticides (ARs)
    Secondary Poisoning of Predators and Scavengers
    Resistance to Anticoagulant Rodenticides
    Further Reading
    Section III Further Issues
    Pollution Problems Worldwide
    International Approaches to Pollution Problems
    Developed and Developing Countries
    Aerial Application of Pesticides
    Further Reading
    Risk Assessment and Legislation
    Risk Assessment of Chemicals
    Statutory Requirements for Risk Assessment of Environmental Chemicals
    The REACH Proposals of the European Union
    Ethical Issues
    Further reading
    Current Issues and Future Prospects
    Diclofenac and Vultures
    The Large-Scale Decline of Bees and Other Pollinators
    Marine Pollution by Polyisobutene (PIB)
    Effects of Mixtures of Environmental Chemicals
    The Design of More Ecofriendly Pesticides and Biocides
    Improved Methods of Ecotoxicity Testing
    Improvements in Procedures for Statutory Risk Assessment of Environmental Chemicals
    Further Reading


    Colin Walker originally qualified as an agricultural chemist. He was responsible for chemical and biochemical studies of environmental pollutants at the Monk’s Wood Experimental Station during the mid-1960s when certain effects of organochlorine insecticides were established. This work led to restrictions on the use of cyclodienes and DDT. He subsequently joined the University of Reading where he taught and conducted research on the molecular basis of toxicity with particular reference to ecotoxicology. Now retired, he is currently affiliated with the Department of Biosciences at the University of Exeter where he contributes to the teaching of a course in ecotoxicology.