POLLUTION THREAT OF HEAVY METALS IN AQUATIC ENVIRONMENTS

Size: px
Start display at page:

Download "POLLUTION THREAT OF HEAVY METALS IN AQUATIC ENVIRONMENTS"

Transcription

1 POLLUTION THREAT OF HEAVY METALS IN AQUATIC ENVIRONMENTS

2 POLLUTION MONITORING SERIES Advisory Editor: Professor Kenneth Mellanby Monks Wood Experimental Station, Abbots Ripton, Huntingdon Previous titles include Quantitative Aquatic Biological Indicators by DAVID J. H. PHILLIPS Biomonitoring Air Pollutants with Plants by WILLIAM J. MANNING and WILLIAM A. FEDER Effect of Heavy Metal Pollution on Plants Volume I-Effect of Trace Metals on Plant Function Volume 2-Metals in the Environment Edited by N. W. LEPp Biological Monitoring of Heavy Metal Pollution by M. H. MARTIN and P. J. COUGHTREY Biological Indicators of Freshwater Pollution and Environmental Management by J. M. HELLAWELL

3 POLLUTION THREAT OF HEAVY METALS IN AQUATIC ENVIRONMENTS GEOFFREY MANCE Regional Scientist, Water Quality, Severn-Trent Water Authority, UK ELSEVIER APPLIED SCIENCE LONDON and NEW YORK

4 ELSEVIER SCIENCE PUBLISHERS LTD Crown House, Linton Road, Barking, Essex IG II 8JU, England Sole Distributor in the USA and Canada ELSEVIER SCIENCE PUBLISHING CO., INC. 655 Avenue of the Americas, New York, NY 10010, USA WITH 62 TABLES AND 36 ILLUSTRATIONS ELSEVIER SCIENCE PUBLISHERS LTD 1987 Softcover reprint of the hardcover 1st edition 1987 First edition 1987 Reprinted 1990 British Library Cataloguiug in Publication Data Mance, Geoffrey Pollution threat of heavy metals in aquatic environments.-(pollution monitoring series) l. Aquatic ecology 2. Water-Pollution 3. Heavy metals-environmental aspects I. Title II. Series 574.5'263 QH541.5.W3 Library of Congress Cataloging-in-Publication Data Mance, Geoffrey Pollution threat of heavy metals in aquatic environments. (Pollution monitoring series) Bibliography: p. Includes index. l. Heavy metals--environmental aspects. 2. Aquatic organisms--effect of water pollution. 3. Water Pollution-Environmental aspects. 4. Water-Pollution Toxicology. I. Title. II. Series. QH545.H42M ' ISBN -13: e-isbn -13: DOl: / No responsibility is assumed by the Publisher for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein. Special regulations for readers in the USA This publication has been registered with the Copyright Clearance Center Inc. (Ccq, Salem, Massachusetts. Information can be obtained from the CCC about conditions under which photocopies of parts of this publication may be made in the USA. All other copyright questions, including photocopying outside of the USA, should be referred to the publisher. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher.

5 Preface The role of the European Community in developing environmental legislation has focused the minds of pollution control agencies and industrialists on the need for, and the evidence to support, water quality standards. This is particularly so for the Dangerous Substances Directive which has led to European standards for cadmium, mercury and lindane. Additionally the United Kingdom has published standards for six other non-ferrous metals. In this book I have sought to review the aquatic toxicity information for these and other metals, not just by the collation of the results of all the published toxicity tests, but by the critical consideration of the test techniques. A surprising proportion of the reported toxicity studies for aquatic organisms are based on unsatisfactory chemical or biological methods. That such weaknesses persist at a time of limited resources for environmental research is disappointing, especially when sound methodologies are extensively documented and widely published. Evaluation of the critically reviewed and vetted data indicates that many of the previously accepted generalisations about the toxicity of metals to aquatic life are invalid: for instance the assumption that salmonid species of fish are more susceptible to these metals than coarse fish, or that increased water hardness decreases toxicity. Too few studies have actually sought to test such hypotheses. In the absence of such general relationships, can standards be developed? The answer is, 'yes'; and where extensive field and laboratory data both exist there is remarkable agreement on the maximum safe concentrations. However, derivation of water quality standards is not an academic exercise and such standards are only one of several tools available to the pollution control agencies. It is important that standards are defined with a clear and unambiguous perception of their intended application. v

6 vi Preface I have therefore tried to follow a line of thought from an appreciation of toxicity testing and the limitations of the data so produced, through field studies to the derivation of standards and their use in calculating discharge limits. In so doing I hope to stimulate some researchers into a better appreciation of the information required for environmental managemen t. Finally I have briefly considered the environmental consequences in a European context. It is obvious that excessive uncontrolled release of toxic metals to the environment is unacceptable because of the inevitable environmental damage caused and the potential threat to human health. Equally in any industrially active society the concept of zero discharge is in reality unachievable, however much it may appeal to the environmentalist. In seeking a balance between these extremes compromise is inevitable. It is arguable that the only secure route to environmental protection is through the control of discharges to ensure that damaging concentrations are not reached in the environment. In Europe, at least, control pressures are leading to the point where the quantities of metals released to the environment will be reduced well beyond the point which will yield additional environmental improvement. That this results from a perception of a public desire for such reductions implies that the same public are prepared to pay for such over-protection. However, in healthy but contaminated environments a situation of diminishing returns already exists. The danger must be that real pollution control will be progressively replaced by bureaucratic control of concentrations for little or no environmental benefit. GEOFFREY MANCE

7 Acknowledgements The views expressed in this book inevitably owe much to the experience I have gained through contact and debate with my former colleagues at the Steven age Laboratory of the Water Research Centre. In particular John Garland tutored me in the manipulation and interpretation of field data and Vince Brown introduced me to the limitations of toxicity test procedures and the evaluation of the results obtained. I must, however, absolve both from responsibility for any of the views expressed in this book which are exclusively, my own, faults and all. Two ladies have assisted me in my labours. One, Mrs Gill Aldridge, is heartily thanked for completing the most onerous chore of manuscript preparation, the typing of the reference list. The other is my wife Elizabeth. That preparation of the manuscript continued in spite of a change of job and the upheaval of moving house is totally due to her active assistance, support and encouragement throughout. Not only is her help warmly appreciated, but she herself is undoubtedly thankful that the task is complete. Much as she deserves the dedication of this book, I feel that it must go to all the water pollution control staff who in the last three decades have been responsible for the steady, yet dramatic restoration of environmental health to the majority of British rivers and estuaries. I only hope that their impt?tus will not be impaired by the bureaucracy arising from the international environmental measures which are now so popular. vii

8 Contents Preface. Acknowledgements. v vii 1 INTRODUCTION Mercury Cadmium Other Metals Sources and Controls 6 2 TOXICITY TESTING TECHNIQUES Introduction Terminology Physical Factors in Toxicity Tests Biological Factors in Toxicity Tests Numbers of Test Animals Chemical Conditions of Tests 16 3 TOXICITY OF METALS TO FRESHWATER FISH Arsenic Cadmium Chromium Copper Lead Mercury Nickel. 62 IX

9 x Contents 3.8 Selenium Silver Vanadium Zinc 67 4 TOXICITY OF METALS TO FRESHWATER INVERTEBRATES Arsenic Cadmium Chromium Copper Lead Mercury Nickel Selenium Silver Vanadium Zinc TOXICITY OF METALS TO MARINE LIFE Arsenic Cadmium Chromium Copper Lead Mercury Nickel Selenium Silver Vanadium Zinc FACTORS AFFECTING TOXICITY Interspecies Variations in Freshwater Fish Interphyletic Variations Freshwater Saltwater Life Stage Water Hardness 237

10 Contents XI 6.5 Temperature ph Salinity Acclimation Fluctuating Exposure Concentrations Mixtures of Metals FRESHWATER FIELD STUDIES Introduction Biological Assessment Zooplankton Benthos Fish Watet Quality Case Studies TIDAL WATER FIELD STUDIES Introduction Physical Factors Chemical Factors Biology Case Studies BIOACCUMULATION Biomagnification of Metals Factors Affecting Bioaccumulation Physiological Condition Growth Salinity and Temperature Age Sex Position Relative to Shoreline and Water Depth Pollutant Interactions Monitoring ENVIRONMENTAL STANDARDS Introduction Derivation of Standards 300

11 xii Contents 10.3 Statistical Expression of the Standard The Relationship between Field and Laboratory Information Effluent Controls from Environmental Standards INTERNATIONAL CONTROLS 313 REFERENCES 331 Index 363