1. Water Science and Technology Directorate, Environment Canada, Burlington, Ontario L7R 4A6 Canada
2. Fisheries & Oceans Canada, Winnipeg, Manitoba R3T 2N6 Canada
3. Faculty of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2 Canada
4. University of Toronto Scarborough, Ontario, M1C 1A4, Canada
5. Department of Occupational Medicine, Aarhus University Hospital, Aarhus, Denmark
6. LS McCarty Scientific Research and Consulting, Ontario, Canada
7. Toxicological Centre, University of Antwerp, 2610 Wilrijk, Belgium