title: Role of snow and cold environment in the fate and effects of nanoparticles and select organic pollutants from gasoline engine exhaust.
abstract: Exposure to vehicle exhaust can drive up to 70 % of excess lifetime cancer incidences due to air pollution in urban environments. Little is known about how exhaust-derived particles and organic pollutants, implicated in adverse health effects, are affected by freezing ambient temperatures and the presence of snow. Airborne particles and (semi)volatile organic constituents in dilute exhaust were studied in a novel low-temperature environmental chamber system containing natural urban snow under controlled cold environmental conditions. The presence of snow altered the aerosol size distributions of dilute exhaust in the 10 nm to 10 μm range and decreased the number density of the nanoparticulate (<100 nm) fraction of exhaust aerosols, yet increased the 100-150 nm fraction. Upon 1 hour exhaust exposure, the total organic carbon increased in the natural snow from 0.218 ± 0.014 to 0.539 ± 0.009 mg L(-1), and over 40 additional (semi)volatile organic compounds and a large number of exhaust-derived carbonaceous and likely organic particles were identified. The concentrations of benzene, toluene, ethylbenzene, and xylenes (BTEX) increased from near the detection limit to 52.48, 379.5, 242.7, and 238.1 μg kg(-1) (± 10 %), respectively, indicating the absorption of exhaust-derived toxic organic compounds by snow. The alteration of exhaust aerosol size distributions at freezing temperatures and in the presence of snow, accompanied by changes of the organic pollutant content in snow, has potential to alter health effects of human exposure to vehicle exhaust.
authors.affiliation: Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, QC H3A 0B9, Canada. parisa.ariya@mcgill.ca.
authors.forename: Yevgen
authors.initials: Y
authors.lastname: Nazarenko
authors.affiliation: Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, QC H3A 0B9, Canada. parisa.ariya@mcgill.ca.
authors.forename: Uday
authors.initials: U
authors.lastname: Kurien
authors.affiliation: PO-Laboratories, Inc., 609 McCaffrey Street, Saint-Laurent, QC H4T 1N3, Canada.
authors.forename: Oleg
authors.initials: O
authors.lastname: Nepotchatykh
authors.affiliation: Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, QC H3A 2K6, Canada.
authors.forename: Rodrigo B
authors.initials: RB
authors.lastname: Rangel-Alvarado
authors.affiliation: Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, QC H3A 0B9, Canada. parisa.ariya@mcgill.ca and Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, QC H3A 2K6, Canada.
authors.forename: Parisa A
authors.initials: PA
authors.lastname: Ariya
mesh_terms: D000336:Aerosols; D000393:Air Pollutants / Q000032:analysis / Q000737:chemistry*; D000397:Air Pollution / Q000032:analysis*; D003080:Cold Temperature; D004784:Environmental Monitoring; D005742:Gasoline / Q000032:analysis*; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry*; D012914:Snow / Q000737:chemistry; D001335:Vehicle Emissions / Q000032:analysis*; D055549:Volatile Organic Compounds / Q000032:analysis / Q000737:chemistry*
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D005742:Gasoline; D001335:Vehicle Emissions; D055549:Volatile Organic Compounds