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Practical Environmental Analysis Second Edition Practical Environmental Analysis Second Edition Miroslav Radojević School of Science and Technology, University of Malaysia Sabah, Malaysia Vladimir N. Bashkin Institute of Urban Ecology, Moscow State University, Institute of Basic Biological Problem...

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Practical Environmental Analysis Second Edition

Practical Environmental Analysis Second Edition

Miroslav Radojevic´ School of Science and Technology, University of Malaysia Sabah, Malaysia Vladimir N. Bashkin Institute of Urban Ecology, Moscow State University, Institute of Basic Biological Problems RAS, Russia

ISBN-10: 0-85404-679-8 ISBN-13: 978-0-85404-679-9 A catalogue record for this book is available from the British Library © The Royal Society of Chemistry 2006 All rights reserved Apart from fair dealing for the purposes of research for non-commercial purposes or for private study, criticism or review, as permitted under the Copyright, Designs and Patents Act 1988 and the Copyright and Related Rights Regulations 2003, this publication may not be reproduced, stored or transmitted, in any form or by any means, without the prior permission in writing of The Royal Society of Chemistry, or in the case of reproduction in accordance with the terms of licences issued by the Copyright Licensing Agency in the UK, or in accordance with the terms of the licences issued by the appropriate Reproduction Rights Organization outside the UK. Enquiries concerning reproduction outside the terms stated here should be sent to The Royal Society of Chemistry at the address printed on this page. Published by The Royal Society of Chemistry, Thomas Graham House, Science Park, Milton Road, Cambridge CB4 0WF, UK Registered Charity Number 207890 For further information see our web site at www.rsc.org Typeset by Macmillan India Ltd, Bangalore, India Printed by Henry Ling Ltd, Dorchester, Dorset, UK

Preface Environmental chemistry is becoming an increasingly popular subject in tertiary education. Courses in chemistry, environmental science, civil engineering, public health, and environmental engineering all have to include environmental chemistry in their syllabuses to a greater or lesser extent. Many textbooks have appeared in recent years aiming to fulfill this requirement; however, most of these mainly deal with theoretical aspects of the subject. This book aims to supplement the existing textbooks by providing detailed, step-by-step instructions for experiments in environmental analytical chemistry. These could be used to teach the practical components of undergraduate and postgraduate (Diploma and Masters) degree courses. The book may also be useful to students on HNC and HND courses, and to those on training courses for technicians working in environmental or other (e.g. public health, sewage, water, industrial) laboratories. Relatively easy experiments, requiring only basic laboratory equipment and instrumentation have been selected. Some of the simpler experiments may also be used by secondary school teachers of chemistry to illustrate applications of chemistry to the environment, a topic of growing concern among today’s school students. Many of the experiments can serve as a basis for more extensive surveys of the environment in school science projects or undergraduate research projects. Treatment of general and analytical chemistry was considered to be outside the scope of this book. It is assumed that the student would be familiar with basic chemical theory, and laboratory procedures and practices. Anyway, many good textbooks dealing with these topics are available and the student can refer to these books in the text where appropriate. Nevertheless, some basic practices of analytical chemistry are dealt with in the introduction and in Appendix B, especially those aspects, which are relevant to environmental analysis. Also, worked examples of problems relating to analytical and environmental chemistry are included where appropriate. The experiments aim to provide practical experience in the analysis of real environmental samples, and to illustrate the application of classical and instrumental techniques to environmental analysis. A brief introduction

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explaining why a particular substance is important and describing its behaviour in the environment is given before each experiment. Easy to follow experimental procedures are then outlined. Suggestions for further study, questions and exercises, and recommended further reading, are given after each experiment. Most undergraduate laboratories would be equipped with the instruments required for carrying out these experiments. Anyway, if any instruments or materials are not available instructors can select experiments that do not require them. This book is not a reference manual for professionals working in environmental laboratories; many comprehensive texts are available for this purpose. Nevertheless, it can serve as an introductory text to those entering into employment in environmental laboratories, especially for those from a nonenvironmental chemistry background. There is a strong bias in the book towards inorganic analysis. This is primarily because equipment for carrying out inorganic analysis is more widely available in teaching laboratories, and it is not meant to reflect the relative importance of inorganic/organic analysis. A large number of organic compounds are present at trace levels in the environment, and their determination requires the use of instruments that tend to be fairly expensive and may not be readily available in many laboratories (e.g. gas chromatographs equipped with mass spectrometer or electron capture detectors). Furthermore, organic analysis requires the purchase of specialised standards, which also tend to be quite expensive. Experimental procedures for these compounds are best left to a future volume dealing with “advanced environmental analysis”. Also, microbiological analyses, such as coliform and Escherichia coli tests, although extremely important from a public health point of view, were not included in the present volume, which is restricted to purely chemical analysis. Inclusion of these tests would have entailed adding considerable background material on environmental microbiology, general laboratory procedures for microbiological analysis, etc. not central to the theme of the present book. This shortcoming is regrettable, but unavoidable. These tests are described in several books dealing with microbiological analysis. Many of the experimental procedures are based loosely on standard methods (APHA, US EPA, British Standards Institution, etc.). The main aim of the book is to serve as an educational tool in preparing environmental chemists for the more demanding regimen of a real environmental laboratory. If the book opens the student’s eyes to the problems and demands of environmental analysis it would have surely served its purpose. Miroslav Radojevic´ Vladimir N. Bashkin September 1998

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While care has been taken to ensure that the information in this book is correct, neither the authors nor the publishers can accept responsibility for the outcome of the experimental procedures outlined in this book.

Preface to the Second Edition Popular wisdom states that “if it isn’t broken don’t mend it”! This book has been received extremely well by academics in chemistry, biology, botany, soil science, geography, and environmental science as a course text at the introductory level. From the glowing reviews it has received, with hardly a note of criticism and few suggestions for improvement, one could be forgiven for thinking that a new edition of the book is not required. After all, most of the methods mentioned in the book are classical and have been well established for years, if not for several decades. Nevertheless, this book is not just a collection of analytical recipes but also aims to give students an understanding of the role of analytical methods in the broader picture of environmental pollution control. As our understanding of the impacts of pollution is constantly improving there have been changes in some of the regulations relating to many of the “classical” pollutants discussed in this book. This is especially true of environmental standards, which are continually changing in the light of new knowledge. Furthermore, newer techniques have been developed for monitoring these pollutants in the environment. It is therefore necessary to keep students updated with the current status of environmental analytical methodology and the associated regulations of these pollutants as well as to keep them informed about present day and future concerns in environmental pollution. For example, in air pollution there has been a shift from ambient to indoor air pollution monitoring in recognition of the fact that most people spend much more time indoors than outdoors, and that their exposure to air pollution is therefore related more to indoor than to ambient pollution levels. The way air pollution is reported has also been changed recently with the Air Quality Index (AQI) replacing the Pollutant Standards Index (PSI) in USA, and AQIs are now being adopted by many industrialised and developing countries. Open path and remote sensing methods are being increasingly used to monitor a wide variety of air pollutants in old (e.g. air quality monitoring, emission testing) and newer (e.g. fence line monitoring, upper atmosphere studies)

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applications. Novel techniques have been developed for characterisation of atmospheric aerosols, including those that can analyse individual particles. New portable monitors are being developed for a variety of air and water pollutants, and personal air pollution monitoring is becoming increasingly popular. Biomonitoring methods are also being adopted as a low cost alternative for monitoring air pollution. There is greater concern over many emerging organic water pollutants (e.g. endocrine disruptors). Although analysis of these pollutants is beyond the scope of this introductory book because of the expensive techniques required, nevertheless, students should have a general awareness of these current issues and this book aims to provide that. Furthermore, there has been a growth in the World Wide Web (www) with new web sites and web pages being added daily as well as greater accessibility to the Internet even in the more remote regions of the globe. Also the Internet is playing a greater role in education, research and business throughout the world at all levels. All these issues have been addressed in the second edition but without making any major changes to the general layout and content of the material in comparison to the first edition. A section has also been included on ethics. It is increasingly being recognised that science and research ethics has to be taught to students at an early stage in order to improve the standard of their work and provide safeguards against scientific fraud. This is no more important than in the field of environmental analysis where low-quality and fraudulent data can have drastic consequences on those affected by environmental pollution as well as the laboratory analyst and researcher reporting such data. Finally, where appropriate, references have been updated and increasing use has been made of www references. A list of useful web sites is also included as well as a list of relevant journals and their web sites. We hope this will be of some value as we wish to see students producing quality research at the earliest stage and publishing their results in international journals. This will no doubt encourage their interest in, and enthusiasm for, protection of the environment, as this will be a major priority for future generations. Hopefully this edition will prove to be useful to students, academics and laboratory technicians for some years to come. Users are directed to appropriate web sites where they may update the various guidelines and standards, which will continue to change and grow in number. Miroslav Radojevic´ Vladimir N. Bashkin September 2005

Acknowledgements We would like to thank all those whose contribution to environmental sciences over the years has given us inspiration and encouragement, especially S.E. Allen, J.P. Lodge Jr., R.M. Harrison, and P. Brimblecombe. We would also like to thank F.L. Wimmer, K.R. Fernando, J. Davies, S.-U. Park, and other colleagues for useful discussions and comments. Thanks also to the Russian Fund of Basic Research (grant no. 96-05-64368) for providing assistance to one of the authors.

CHAPTER 1

Introduction 1.1 THE ENVIRONMENT The environment is the sum total of human surroundings consisting of the atmosphere, the hydrosphere, the lithosphere, and the biota. Human beings are totally dependent on the environment for life itself. The atmosphere provides us with the air we breathe, the hydrosphere provides the water we drink, and the soil of the lithosphere provides us with the vegetables that we eat. In addition, the environment provides us with the raw materials to fulfill our other needs: the construction of housing, the production of the numerous consumer goods, etc. In view of these important functions, it is imperative that we maintain the environment in as pristine a state as is possible. Fouling of the environment by the products of our industrial society (i.e. pollution) can have many harmful consequences, damage to human health being of greatest concern. In addition to the outdoor environment, increasing concern is being expressed about the exposure of individuals to harmful pollutants within the indoor environment, both at home and at work. Levels of harmful pollutants can often be higher indoors than outdoors, and this is especially true of the workplace where workers can be exposed to fairly high levels of toxic substances. Occupational health, occupational medicine, and industrial hygiene are subjects that deal with exposure at the workplace. Pollution is mainly, although not exclusively, chemical in nature. The job of the environmental analyst is therefore of great importance to society. Ultimately, it is the environmental analyst who keeps us informed about the quality of our environment and alerts us to any major pollution incidents, which may warrant our concern and response. 1.1.1 Biogeochemical Cycles The different components of the biosphere and their interactions are illustrated in Figure 1.1. The biosphere is that part of the environment where life

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Chapter 1

Figure 1.1 Interactions between component parts of the biosphere

exists. It consists of the hydrosphere (oceans, rivers, and lakes), the lower part of the atmosphere, the upper layer of the lithosphere (soil), and all life forms. The concept of the biosphere was first introduced by the Russian scientist Vladimir Vernadsky (1863–1945) as the “sphere of living organisms distribution”. Vernadsky was among the first to recognise the important role played by living organisms in various interactions within the biosphere, and he established the first-ever biogeochemical laboratory specifically dedicated to the study of these interactions. He expounded his theories in an aptly entitled book, “Biosphere”, published in 1926. The various spheres act as reservoirs of environmental constituents and they are closely linked through various physical, chemical, and biological processes; there is constant exchange of material between them. Chemical substances can move through the biosphere from one reservoir to another, and this transport of constituents is described in terms of a biogeochemical cycle. Biogeochemical cycles of many elements are closely linked to the hydrological cycle. The hydrological cycle acts as a vehicle for moving water-soluble nutrients and pollutants through the environment. If all the components of the cycle are identified and the amounts and rates of material transfer quantified, the term budget is used. Both beneficial nutrients and harmful pollutants are transported through biogeochemical cycles with farreaching consequences. The more commonly discussed biogeochemical cycles are those of important macronutrients such as carbon, sulfur, nitrogen, and phosphorus, but, in principle, a biogeochemical cycle could be drawn up for any substance. The cycle is usually illustrated as a series of compartments (reservoirs) and pathways between them. Each reservoir can be viewed in terms of a box model shown in Figure 1.2.

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Introduction

Figure 1.2 The box model

If the input into a reservoir equals the output, the system is said to be in a steady state. The residence time, τ, is defined as Amount of substance in the reservoir (mass) τ ⫽ ᎏᎏᎏᎏᎏ Flux (mass/time)

Flux is the rate of transfer through the reservoir (i.e. the rate of input or output). If the input exceeds the output, there will be an increase in the amount of substance in the reservoir. There are many examples of the build-up of pollution in environmental systems since pollutants are often added at rates greater than the rates of natural processes that act to remove them from the system. On the other hand, if the output is greater than the input, the amount of substance in a reservoir will decrease. An example of this is the depletion of natural resources. It is debatable whether, in the absence of human activities, natural systems would tend towards some sort of steady state or equilibrium. Natural systems are dynamic, and both natural and human-induced disturbances lead to change, albeit over different time scales. Natural changes to biogeochemical cycles generally take place over geologic time scales, and for millennia these cycles have maintained the delicate balance of nature conducive to life. However, since the industrial revolution, and especially over the last 40 years, human activities have caused significant perturbations in these cycles. The effects of these disruptions are already becoming apparent, and are likely to become even more severe in the coming millennium. Serious environmental problems that have been caused by disruptions of biogeochemical cycles include: global warming, acid rain, depletion of the ozone layer, bioaccumulation of toxic wastes, and decline in freshwater resources. Modelling of biogeochemical cycles is becoming increasingly important in understanding, and predicting, human impacts on the environment, and the possibility of using biogeochemical cycles to solve environmental problems, the so-called biogeochemical engineering, has recently been recognised.Some of the major human impacts on biogeochemical cycles are given in Table 1.1. The extent of human impacts on biogeochemical cycles can be illustrated by comparing the contribution of anthropogenic emissions to the atmosphere with natural emissions (Table 1.2). For some toxic substances, the contribution of industrial emissions is even more striking; the ratio of anthropogenic

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Table 1.1 Human impacts on biogeochemical cycles Cycle

Human interference

Environmental consequence

Carbon Sulfur Nitrogen Phosphorus

Fossil fuel combustion, clearing of forests Fossil fuel combustion Fossil fuel combustion, fertilizers Detergents and fertilizers

Global warming Acid rain Acid rain, eutrophication Eutrophication

Table 1.2 Relative contributions of anthropogenic and natural sources (approximate) Pollutant

Emissions to the atmosphere (% of total) Natural Anthropogenic

Sulfur dioxide Oxides of nitrogen Carbon dioxide Hydrocarbons

50 50 95 84

50 50 5 16

to natural emissions to the environment is 3:1 for arsenic, 5:1 for cadmium, 10:1 for mercury, and 28:1 for lead. 1.1.2 Environmental Pollution Pollution is commonly defined as the addit...