D D • • á NATURAL ENVIRONMENT RESEARCH COUNCIL INSTITUTE OF TERRESTRIAL ECOLOGY METALS IN ANIMALS I T E SYMPOSIUM NO. 12 EDITED BY D. OSBORN ITE, MONKS WOOD EXPERIMENTAL STATION, ABBOTS RIPTON, HUNTINGDON PROCEEDINGS OF A WORKSHOP HELD AT MONKS WOOD EXPERIMENTAL STATION 15-16 SEPTEMBER 1982 Printed in Great Britian by NERC/SERC Reprographic Services, Swindon C NERC Copyright 1984 Published in 1984 by Institute of Terrestrial Ecology 68 Hills Road Cambridge CB2 1LA ISBN 0 904282 77 5 ISSN 0263 8614 ACKNOWLEDGEMENTS Mrs June Stokes prepared the camera-ready typescript from the author's original material. Her diligence in doing this exacting job is greatly appreciated. Thanks are also due to John Williamson for drawing several of the figures, to Mrs Jean King and John Beckett of the ITE library for advice on references, and to Penny Ward for editorial assistance. COVER ILLUSTRATIONS Sketch studies of crab by C F Tunnicliffe OBE RA, by kind permission of the beneficiaries of his estate Bank vole photograph Dr P A Morris, Royal Holloway College, London Fulmar photograph Dr R K Murton Puffin photograph Dr M P Harris Swan on River Thames photograph Dr M Birkhead, Oxford University Cover design C B Benefield The Institute of Terrestrial Ecology was(ITE) established in 1973, from the former Nature Conservancy's research stations and staff, joined later by the Institute of Tree Biology and the Culture Centre of Algae and Protozoa. ITE contributes to, and draws upon, the collective knowledge of the fourteen sister institutes which make up theNatural Environment Research Council,spanning all the environmental'sciences. The Institute studies the factors determining the structure, composition and processes of land and freshwater systems, and of individual plant and animal species. It is developing a sounder scientific basis for predicting and modelling environmental trends arising from natural or man-made change. The results of this research are available to those responsible for the protection, management and wise use of our natural resources. One quarter of ITE's work is research commissioned by customers, such as the Department of Environment, the European Economic Community, the Nature Conservancy Council and the Overseas Development Administration. The remainder is fundamental research supported by NERC. ITE's expertise is widely used by international organizations in overseas projects and programmes of research. D Osborn Institute of Terrestrial Ecology Monks Wood Experimental Station Abbots Ripton HUNTINGDON Cambridgeshire PE17 2LS 04873 (Abbots Ripton) 381 • CONTENTS Page No. INTRODUCTION .. 3 I ACCUMULATION EFFECTSAND METALSOF Food chain relationships of copper and cadmium in herbivorous and insectivorous_small mammals . B A HUNTER, M S JOHNSON & D J THOMPSON 5 Cadmium within a contaminated grassland ecosystem established on metalliferous mine waste S M ANDREWS & J A COOKE . • • 11 Lead poisoning in the mute swan M BIRKHEAD 16 Lead poisoning in mute swans- an East Anglian survey M C FRENCH . 25 Cadmium and mercury in seabirds D OSBORN & J K NICHOLSON 30 Mersey estuary bird mortalities D OSBORN , K R BULL & WENDY J YOUNG • • 35 I I LOCALISATION OF METALS IN ANIMAL TISSUES Cadmium induced lesions in tissuesSorex of araneus from metal refinery grasslands B A HUNTER, M S JOHNSON & D J THOMPSON 39 Localisation of metals in mussel kidney B J S PIRIE . • .. 45 • Page No. The effects of cadmium on the concentrations of some naturally occurring intracellular elements in the kidney MARION D KENDALL, J K NICHOLSON & ALICE WARLEY50 I I I METALLOTH I ONE I N Functions of metallothionein K CAIN . • • • • • • 55 The effect of mercaptoethanol on the chromatographic properties of crab(Cancer pagurus) metallothionein J OVERNELL . • • • • 62 The isolation of copper-metallothionein from the particulate fractions of pig liver R K MEHRA & I BREMNER • • • • • 67 Proton NMR studies of plaice liver metallothionein: metal removal by EDTA J K NICHOLSON, P J SADLER & J OVERNELL . 72 List of contributors and participants 3 INTRODUCTION Toxic metals are part of the environment. Man's industry and agriculture redistribute these metals, concentrating them from ores, discarding others in effluents, and even applying some to crops as pesticides. In some parts of the world, substantial leaching of metals from soils may be occurring because of groundwater acidification. So, as a result of man's activities, animals and plants can be exposed to abnormal amounts of toxic metals. This exposure can lead to the accumulation of pharmacologically significant concentrations of metals in plant and animal tissues. Interestingly, there are also circumstances in which plants and animals accumulate toxic metals from natural sources. Clearly, the environmental and ecological significance of these metal burdens in man, agricultural products and wildlife needs to be assessed, and suitable measures taken to minimise any harm that is being done. For this reason, much research into the effects of toxic metals has been done in recent years, and there are now many examples of adverse effects on wildlife, domesticated animals, and man. However, when working with toxic metals, the essential role that many metals play in normal physiology must never be forgotten. Studies of toxic metals, whether done for environmental monitoring or to determine harmful effects, will almost always be improved by simultaneous consideration of the essential metal status of the animal, plant or ecosystem concerned. This can be illustrated in a number of ways: for example, the amount of essential metal in the diet, the amount in any one tissue or biochemical compartment, can influence the absorption and distribution of the toxic metal and hence, in all probability, modulate its effects. Furthermore, in common with studies on other toxic chemicals, under- standing the effects of a toxic metal depends on a thorough knowledge of the affected species' normal physiology. Such understanding is particularly necessary if we wish to make an attempt to assess the importance of an effect of a toxic metal in the life of wild animals or plants, because, while a toxic metal may disrupt a particular biochemical or physiological function in all animals or plants, the importance of that function will vary in different animals and plants and may even vary from time to time in any one species. Changes in functional response could lead to widely different whole animal manifestations of the effects of metals, and suggest that we cannot make environmental or ecological assessments without a good deal of biochemical and physiological knowledge. Studies of the effects of toxic metals in the environment also benefit from parallel studies in the relatively controlled conditions of the laboratory, because, no matter how carefulwe are, effects seen in the wild could be due, not to the metal, but to some factor of which we were unaware. Laboratory work can do much to help confirm that the effects seen in the wild really were due to the chemical or metal concerned. From the precedingparagraphs, it is apparentthat a multi- disciplinaryapproach is requiredto understandthe toxiceffects of metals. So, I thoughtit wouldbe valuableto bring togethera number of researchworkers who, becausethey belong to groupsworking on such diverseaspects of metalproblems, might not ever have an opportunity of meeting. In designingthe workshop,3 areasof work seemedparticularly importantand interesting:- 1. Studieson the accumulationof metalsby wildlifeand on the effectsof the metals. 2. Studiesattempting to determinethe localisationof metalsin cells. 3. Studieson the metallothioneins,those ubiquitous but intriguing proteinswhose role in traceelement metabolism and metal toxicologystill defies definition more than 20 yearsafter the proteinwas firstdescribed. Only the readerwill be able to judgewhether the combinationof expertiserepresented in the papersin thisvolume helps to showhow inter-laboratoryco-operation and a multi-disciplinaryapproach to metalscan increaseour knowledgeand understanding.If nothingelse, the papersshow what is beingdone acrossa broadrange of specialities, and, in that context,it is of interestthat 4 of the 5 UK research councils(ARC, MRC, NERC and SERC)have supportedthe effortsof the workerswho tookpart in thismeeting. D Osborn . November1983 • I. ACCUMULATION AND EFFECTSOF METALS á 5 FOOD CHAIN RELATIONSHIPS OF COPPER AND CADMIUM IN HERBIVOROUS AND INSECTIVOROUS SMALL MAMMALS B A HUNTER*, M S JOHNSON** and D J TEKNOSOlq* *Department of Zoology **Department of Botany University of Liverpool, P 0 Box 147, Liverpool L69 3BX ABSTRACT This paper contrasts the transfer of copper and cadmium through the food chains of contaminated grasslands. Particular emphasis is placed on the accumulation of metals by endemic populations of herbivorous and insectivorous small mammals. Copper was found to be highly mobile through the soil-plant-invertebrate system. However, natural homeostatic mechanisms prevent significant copper accumulation in small mammals. In contrast, cadmium shows much greater mobility and bioconcentration throughout the food chain. By virtue of respective dietary contamination levels, the insectivorous common shrew accumulates 10-fold more cadmium than the herbivorous field vole occupying the same contaminated grass- lands. The important influences of diet, trophic status and metal speciation on food chain transfer and relative accumulation of metals by small mammals are discussed. INTRODUCTION Trace metal accumulation in small mammals