Spatial and Temporal Variations of Ultrafine Particles in a Residential Area Near an Airport

CHEOL H. JEONG, Junshi Xu, Weaam Jaafar, Emily Farrar, Danny Anwar, Isaac Nielsen, Matthew Tamura, Marianne Hatzopoulou, Greg J. Evans, SOCAAR, University of Toronto

     Abstract Number: 335
     Working Group: Aerosol Exposure

Abstract
Urban air pollution is a result of a complex interaction between regional and local sources, which can be influenced by various factors such as proximity to transportation infrastructures and local meteorology. An increasing number of studies have shown that people living near major highways and airports are at a higher risk of developing air pollution-related health issues compared to those living further away. Comprehensive measurement and data analysis are crucial to better understand the contribution of different sources to air pollution.

Gaseous and particle phase air pollutants, including ultrafine particles (UFP), black carbon (BC), and criteria pollutants were measured in a residential neighbourhood near an airport and major roads in Toronto. Stationary sampling was conducted in three seasons in 2020 (Jan-Feb, Apr-May, and Jul-Sep). Follow-up measurement was performed at four locations within the neighbourhood from Jun to Aug 2022 to investigate temporal and spatial pollutant variations and compare pre/during/post COVID-19 lockdown levels. Additionally, data from two long-term air monitoring stations located 2.5 km north and south of the community were compared. Air navigation information, such as aircraft types, takeoff, and landing, was analyzed to evaluate the influence of aircraft activities on the levels of UFP and BC in the neighbourhood.

The average concentrations of criteria pollutants such as PM_2.5 and NO_x in the neighbourhood were found to be similar to other parts of Toronto. However, the concentration of UFP was approximately 3 times higher in the neighbourhood when the wind blew from the airport than in the opposite direction. A steep spatial gradient of UFP was observed, with levels decreasing as the distance from the airport increased. Furthermore, BC levels in the residential area were higher than those at the air monitoring stations. The electrification of the diesel ferry produced benefits in mitigating BC and NO_x in the area.