title: Contrasting reactive oxygen species and transition metal concentrations in combustion aerosols.
abstract: The presence of reactive oxygen species (ROS) and 10 transition metals (Ag, Cd, Co, Cu, Fe, Mn, Ni, Ti, V and Zn) in both the acid-soluble and water-soluble fractions of fine particles of combustion origin were determined. ROS was analyzed using the dichlorofluorescin fluorescence technique. Particles emitted from on-road vehicles, gas cooking, incense burning, and cigarette smoke were characterized along with those in the background air of outdoor and indoor environments. In addition, this study evaluated the possible relationships between ROS and individual transition metals. It is found that cigarette smoke which had the highest concentration of metals also contained the highest concentration of ROS. Regression analysis performed showed that water-soluble metals including Cd, Co, Cu, Fe, Mn, and Ni showed better correlation with ROS concentration as compared to acid-soluble (total) metals. The findings demonstrated that water-soluble metals could be one of the species influencing ROS formation in ambient air.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore.
authors.forename: S W
authors.initials: SW
authors.lastname: See
authors.forename: Y H
authors.initials: YH
authors.lastname: Wang
authors.forename: R
authors.initials: R
authors.lastname: Balasubramanian
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D005452:Fluoresceins; D005579:Fossil Fuels / Q000032:analysis; D008163:Luminescent Measurements; D019216:Metals, Heavy / Q000032:analysis*; D017382:Reactive Oxygen Species / Q000032:analysis*; D012044:Regression Analysis; D012846:Singapore; D012906:Smoke / Q000032:analysis*; D013053:Spectrophotometry; D014026:Nicotiana; D001335:Vehicle Emissions / Q000032:analysis
chemical_list: D000393:Air Pollutants; D005452:Fluoresceins; D005579:Fossil Fuels; D019216:Metals, Heavy; D017382:Reactive Oxygen Species; D012906:Smoke; D001335:Vehicle Emissions; C037631:2',7'-dichlorofluorescein