JEROME O. NRIAGU is Professor in the Department of Environmental and Industrial Health, School of Public Health, the University of Michigan, and an adjunct professor at the University of Waterloo. For many years he was a research scientist with the National Water Research Institute, Burlington, Ontario. He is the editor of the Wiley Series in Advances in Environmental Science and Technology and has edited, among many other volumes, Nickel and Human Health, Arsenic in the Environment, and Thallium in the Environment. Dr. Nriagu received BSc and DSc degrees from the University of Ibadan, Nigeria, an MS from the University of Wisconsin, Madison, and a PhD in geochemistry from the University of Toronto. He has published extensively in leading geochemical and environmental science journals and has received a number of awards for his work. He is a Fellow of the Royal Society of Canada. John B. Sprague is former professor at the University of Guelph, Canada, and president of J.B. Sprague Associates, Ltd. For 12 years, he was Scientist-in-Charge for pollution studies in the Atlantic Provinces, working with the Fisheries Research Board of Canada. He was a University of Guelph faculty member for more than 20 years.

• Will We Ever Get Ahead of the Problems? (H. Regier). Aquatic Toxicology in Management of Marine Environmental Quality: Present Trends and Future Prospects (M. Waldichuk). Survival of Lake Charr (Salvelinus Namaycush) Embryos Under Pulse Exposure to Acidic Runoff Water (J. Gunn). Hematological Parameters and Parasite Load in Wild Fish with Elevated Radionuclide Levels (J. Bernstein & S. Swanson). Colorimetric Determination of Cyanide in Aquatic Systems (M. Mehra & A. Arseneau). Nafion Dialysis Procedure for Speciation of Metal Cations (C. Bourque & R. Guy). Metallothionein Messenger RNA: Potential Molecular Indicator of Metal Exposure (K. Chan, et al.). Avoidance Tests with a Plating Industrial Effluent (J. Hadjinicolau & L. Spraggs). Development of Multiresistance Patterns in the Bacterial Flora of Trout Following an Antibiotic Therapy (R. Leger & R. Lallier). Toxicity Testing of Sediments: Problems, Trends, and Solutions (M. Samoiloff). Role of Dissolved Oxygen in the Desorption of Mercury from Freshwater Sediment (J. Wang, et al.). Integrated Ecotoxicological Evaluation of Effluents from Dumpsites (R. Van Coillie, et al.). The Use of a Fugacity Model to Assess the Risk of Pesticides to the Aquatic Environment of Prince Edward Island (L. Burridge & K. Haya). Assessment of the Inorganic Bioaccumulation Potential of Aqueous Samples with Two Algal Bioassays (S. Bisson, et al.). Biodegradation of Petroleum in the Marine Environment and Its Enhancement (K. Lee & E. Levy). Pesticides in Forestry and Agriculture: Effects on Aquatic Habitats (D. Eidt, et al.). Index.