Health of the Northwest Atlantic
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12072412 Health of the Northwest Atlantic _,,,,,,,,,,..,. - Canada Published jointly by: Environment Canada, and Department of Fisheries and Oceans HEALTH OFTHE NORTHWEST ATLANTIC A Report to the Interdepartmental Committee on Environmental Issues Edited by R. C. H. Wilson Environmental Protection Service, Environment Canada, and R. F. Addison Department of Fisheries and Oceans, Marine Ecology Laboratory, Bedford In stitute of Oceanography Avail able from: Environment Canada Bedford Institute of Oceanography 45 Alderney Drive and Dartmouth, N.S. Dartmouth , N.S. B2Y 4A2 B2Y 2N6 Correct citation of this volume is: Health of the Northwest Atlantic. R.C.H. Wilson and R.F. Addison (eds.). Department of the Environment/Department of Fisheries and Oceans 1 Department of Energy, Mines and Resources. ^ ^ ^ p. (1984) ISBN 0-662-13072-3 DSS (at. No. EN 40-319 i l 984E CONTENTS 1. Introduction R. C.H. Wilson . 5 2. Oceanographic Setting L.P. Hildebrand. Physical oceanography, Currents, Winds and waves, Fog, Temperature and salinity, Tides, Ice, Biological oceanography, Primary and secondary production, Fish resources, Marine mammals, Marine birds, Summary........................................... 8 3. Geological Processes and Factors D. J. W. Piper. Geological setting, Bedrock,. Glacial and post-glacial sediments, Surficial distribution of sediments, Seabed erosion and transport of sediment, Waves and currents, Bioturbation, Iceberg scour, Slumping, Sediment deposition on the continental shelf, Sediment sources, Depositional processes, Chemical fluxes through bottom sediment, Conclusions.. 31 4. River Input of Pollutants to the Western North Atlantic R.F. Addison. 42 5. Contaminant Transport through the Marine Environment E. W. Brandon and P.A. Yeats. Atmospheric dispersion, Atmospheric transport and deposition, Marine transport dispersal and removal mechanisms, Carbon dioxide, Trace metals, Organochlorine compounds . 44 6. Radioactivity in the Marine Environment J.N. Smith. Sources of radioactivity, Cs-137 and Sr-90 distributions, Fission and ac tivation products, Carbon-14 and tritium, Plutonium, Uranium and thorium decay series . 56 7. Incidence and Distribution of Petroleum and Petroleum Products E.M. Levy . 70 8. Organohalogen Compounds R.F. Addison. Organochlorine concentrations in the Northwest Atlantic, Water column, Marine sediments, Invertebrates, Finfish, Seals, Conclusions, Temporal trends, Significance of present OC levels . 77 9. Non-halogenated Synthetic Organic Chemicals R.A.F. Matheson. Pesticides, Agricultural application, Forest spraying, Commercial chemicals, Phthalate acid esters, Organophosphates, Aromatic amines, Organotins, Organic arsenicals, Summary. 85 10. A Perspective on Potential Environmental Problems Associated with Chlorine Usage J.F. Payne and A. Rahimtula. Chlorine usage, Chlorine chemistry, Recent concerns about chlorine usage, Drinking water, Aquatic environmental toxicity, Paper mills, Sewage, Fish plants, Environmental persistence, Man and nature as sources, Conclusions . 94 11. Coal and Coal-Based Products P.B. Eaton, J.F. Uthe and G.R. Sirota. Coal mining in the Atlantic region, Coal in power generation, Marine impacts from use of coal, Air emissions, Local effluents, Coal-based products, Coal-based liquids, Problems associated with coal-based products . 109 12. Distribution and Bioavailability of Heavy Metals in the Marine Environment S. Ray and J.M. Bewers. Distribution in the natural environment, Water, Sediment, Biota, Accumulation from different sources, Water, Sediment, Food, Conclusions........ 121 13. The Effects of Heated Effluents on Marine Water Quality in the Atlantic Region J.J. Swiss. General effects of heated effluents, Sources, Area of impact, Types of impact, Heated effluents in the atlantic region, Nova Scotia, New Brunswick, Newfoundland, Prince Ed'?rd Island, Summary . 138 14. Persistent Litter P.B. Eaton. Kinds of materials, Sources of litter, Environmental problems, Aesthetic problems, Hazard to marine life, Hazard to ships and fishermen . 145 15. Micro-Organisms and Pathogens A. Menon and P.K. Klaamas. Role of micro-organisms in self-purification of waters, Pathogens I in waters, Salmonellosis, Shigellosis, Cholera, Vibrio parahaemolyticus, Viruses, Other waterborne pathogens, Sources of microbial contamination, Effects on coastal waters ........ 153 16. Resolution of Marine Pollution Problems A. Mciver. Un derstanding, Education, Legislation, Technology, Cost.. 165 17. Summary and Conclusions R.F. Addison................... 174 INTRODUCTION R.C.H. Wilson* The earliest fossil remains of living organisms are associated with ancient seas. From the time of his oldest written records, man has sailed in ships over the sea and exploited the resources beneath its surface, building a modern society with cultural and economic characteristics strongly in fluenced by the sea and its biological foundation. Today, despite every school-child's knowledge that oceans occupy about two-thirds of the world's surface, despite the fact that about 6.5% of the animal protein consumed in Canada1 comes from the sea, concern for the health of the ocean is still not widespread. The sea has tended to preoccupy only those who made a living by it. Even for its most intimate acquaintances, its ob vious size and power have allayed most fears that man's activities will change it in a meaningful way. Since confederation, the ocean and its users have been under the study or control of federal government departments housed in the provinces bordering the Atlantic coast. The regional heads of these departments together comprise the Interdepartmental Committee on Environmental Issues. Some records, lobster catch statistics for example, have been maintained since the last century. Other information, such as en vironmental levels of organic contaminants, is much more recent in comparison. The foci of study and control expand and shift to reflect the pressures of new patterns of technological development, resource ex ploitation and transportation. The western North Atlantic has traditionally been used as a fishing grounds. In 1977 the fisheries of the four Atlantic Provinces plus Quebec together totalled one million tonnes and about two-thirds of the marketed 2 value of all Canadian fish • While expectations of future catch include increases for some species, the overall yield is not expected to change much in the period 1980-85. The fastest growing sector of the industry is probably aquaculture, where the number of operations has risen from 16 in 1975 to 59 in 1983. The commercial fishery is dependent on a satisfactory level of environmental quality. Abnormally high levels of pollutants would not only threaten the viability of fish stocks but could also lead to accumulations which would prevent the sale of fish or fish products for human con sumption. The culture of shellfish is especially vulnerable in this respect, in that it is a coastal activity whose water quality requirements conflict with the common use of estuaries and bays to treat domestic sewage. Development of the oil and gas resources off the Atlantic Cai:iadian coast has beeri an important regional issue for at least five years. Ex ploration activity in recent years has remained fairly steady, with 15 wells drilled in 1982, but it is expected to double by 1985. Exploration is occuring • Environmental Protection Service, Environment Canada, Dartmouth, N.S. 5 mainly on the Scotian Shelf, the Grand Banks off Labrador, and in the Gulf of St. Lawrence. Development drilling is imminent for the Venture gas structure off Sable Island and the Hibernia oil structure on the Grand Banks. Environmental risks center on the possibility of an accident during drilling, production or transportation. While studies of oil spills elsewhere generally indicate that long term impact is highly localized and can be almost eliminated by thorough cleanup, chronic impacts from spills and from normal operational inputs have been documented. While the offshore oil and gas industry is perhaps the most visible threat to ocean quality, it is not the most important. A compilation of statistics on the input of pollutants showed that atmospheric and riverine inputs were the largest sources of nutrients and toxic metals to the North Sea3, despite the intensity of the offshore oil and gas industry. Similar statistics for the western North Atlantic are unavailable, but it is to be expected that the major inputs in this region would be associated with in dustries located onshore. The papers comprising this volume were assembled to bring together information about some of the pressures on organisms off the _Canadian Atlantic coast. The levels and distribution of chemical contaminants, especially some distance from shore, are of concern to scientists and regulators because trends in this area are measured and influenced more slowly t_han in terrestrial ecosystems. The oceans, too, are part of the global commons to whose managenierit and preservation national governments are generally committed. 'Knciw'Iedge of contamination and the response of marine communities to it is an essential part of the Canadian strategy for their protection. The focus of the papers which follow thus tends towards the offshore rather than the estuaries and coastal embayments where the better known and perhaps more serious pollution problems exist. By necessity arising from their scope, the papers are all fairly general but they indicate, I believe, that scientists working in the Atlantic Region have