1. ICES, Toronto, Ontario, Canada
2. Public Health Ontario, Toronto, Ontario, Canada
3. Department of Geography and Environmental Studies, Ryerson University, Toronto, Ontario, Canada
4. Health Canada, Ottawa, Ontario, Canada
5. Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
6. Air Health Science Division, Health Canada, Ottawa, Ontario, Canada
7. Department of Environmental Health Sciences, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California, USA
8. Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
9. Department of Family and Community Medicine, University of Toronto, Toronto, Ontario, Canada