1. Air Quality Processes Research Section, Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada
2. Suncor Energy Inc., Calgary, Alberta T2P 3Y7, Canada
3. College of Environmental Science and Engineering, Peking University, Beijing 100871, China
4. Dalla Lana School of Public Health and Department of Chemical Engineering and Applied Chemistry, University of Toronto, 223 College Street, Toronto, Ontario M5T 1R4, Canada