1. Department
of Civil Engineering, University of Toronto, Toronto, Ontario Canada, M5S 1A4
2. Division
of Clinical Epidemiology, McGill University, Montreal, Quebec Canada, H4A 3J1
3. Air
Quality Processes Research Section, Environment and Climate Change Canada, Downsview, Ontario Canada, M3H 5T4
4. School
of Urban Planning, McGill University, Montreal, Quebec Canada, H3A 0C2