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Fifield-Haines: Environmental Analytical Chemistry
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In the final quarter of the twentieth century the health of our global environment has become a matter of wide concern. This concern has stimulated a wide ranging and intensive search for an understanding of the way in which the natural environment functions, and the way in which the human race is bringing about environmental changes. These studies are heavily dependent on observation and quantitative measurements. It is clearly impossible to discuss sensibly the greenhouse effect without measurement of atmospheric carbon dioxide level; eutrophication of a lake without measurement of dissolved oxygen and nutrients; or heavy metal pollution without measurement of metal concentrations in soils and water. Many different parameters are studied, and diverse types of measurements made. These measurements must be designed and executed so as to be both relevant to the problem being studied, and reliable in themselve, i.e. they must be valid. Only by a proper understanding of the capabilities and limitations of the measurement methods themselves, and the context within which they are being applied can such validity be ensured. Increasingly, measurements are also made to demonstrate compliance with a framework of environmental legislation and regulations. Many environmental studies are concerned with the amounts and distribution of chemical species. Very many different species with diverse properties are of interest. These species may be elements or compounds, simple or complex in structure, organic or inorganic, natural or art)ficial in origin, and occur at vastly different levels of concentration. Measurements in this context fall very much into the realm of analytical chemistry, which is the central theme of this book. The challenges of chemical analysis in the environmental context are immense, demanding high levels of expertise and skill across a wide range of analytical methodology. In compiling this book we have firstly, in chapter 1, addressed the fundamental questions of the general properties of analytical measurements and in chapter 2, their limitations, validity and interpretation. Secondly, we have recognised the importance of a knowledge of fundamental chemical principles to anyone seeking to develop a proper understanding of chemical analysis. Readers with strong chemical backgrounds can ignore chapter 3, but it is the nature of environmental science to involve people from diverse initial subject areas. We anticipate, therefore, that a significant number of our readers will find reference to chapter 3 helpful at various times. It has been accepted by us from the outset that it is not sensible to attempt a fully comprehensive coverage of environmental analytical chemistry, and we have concentrated on those techniques, methods and applications which seem to us to be the most important. Chapter 12 on the use of biological indicators in environmental assessments could be considered to be outside the strict realms of analytical chemistry. However, in practice the two areas are often so closely interdependent in use, that we have taken the view that it should be included. In order to sustain the appropriate level of expertise across the diversity of subject matter, chapters have been written by specialists and significant numbers of the examples used throughout the text are drawn from the personal experiences of the authors. We are grateful for the many discussions that we have had over the years with colleagues, discussions which have helped shape our approach to environmental analytical chemistry, and, from time to time, to correct misconceptions. The hard work and forbearance of the publishers are also fully acknowledged. |