title: Changes in chemical composition and oxidative potential of urban PM(2.5) between 2010 and 2013 in Hungary.
abstract: A comprehensive chemical characterization and oxidative potential (OP) assessment of PM2.5 was carried out at an urban site of Budapest between June 2010 and May 2013 to investigate the seasonal variability of particulate phase air pollutants and their oxidative activity. Chemical analyses included the determination of the concentration of trace elements, major water-soluble inorganic ions and carbonaceous fractions (total carbon, water-soluble organic carbon, organic carbon, elemental carbon). The OP of PM2.5 was assessed by antioxidant depletion using a synthetic respiratory tract lining fluid containing ascorbate, reduced glutathione and urate. The mean PM2.5 mass concentration (21.0 μg m(-3)) was just below the 25 μg m(-3) annual mean PM2.5 limit value set by the European Commission and showed a seasonal pattern with higher levels during winter. On average, 84% of the gravimetric mass could be reconstructed by the chemical measurements. Organic matter and secondary inorganic ions were the most dominant PM2.5 constituents contributing 40 and 29% of its mass, respectively. Changes in the yearly concentrations were not identified for the investigated compounds between 2010 and 2013. Temporal differences in both ascorbate and glutathione oxidation could be observed during the 3-year long sampling period; however, no clear seasonal trend was apparent. OP metrics were associated mainly with traffic-related trace elements; however, other PM sources (i.e., long-range transport, secondary aerosol formation) could also contribute to particulate OP in Budapest. The weak correlation between OP metrics and PM2.5 mass concentration suggests the possibility of using OP as an additional metric in epidemiology.
authors.affiliation: Cooperative Research Centre for Environmental Sciences, Eötvös Loránd University, Pázmány Péter stny. 1/A, H-1117 Budapest, Hungary; Hungarian Satellite Trace Elements Institute to UNESCO, Pázmány Péter stny. 1/A, H-1117 Budapest, Hungary. Electronic address: tamas.szigeti@yahoo.com.
authors.forename: Tamás
authors.initials: T
authors.lastname: Szigeti
authors.affiliation: Cooperative Research Centre for Environmental Sciences, Eötvös Loránd University, Pázmány Péter stny. 1/A, H-1117 Budapest, Hungary; Hungarian Satellite Trace Elements Institute to UNESCO, Pázmány Péter stny. 1/A, H-1117 Budapest, Hungary. Electronic address: ovari@chem.elte.hu.
authors.forename: Mihály
authors.initials: M
authors.lastname: Óvári
authors.affiliation: MRC-PHE Centre for Environment and Health, King's College London, 150 Stamford Street, SE1 9NH London, UK; National Institute for Health Research Health Protection Research Unit in Health Impact of Environmental Hazards, King's College London, 150 Stamford Street, SE1 9NH London, UK. Electronic address: christina.dunster@kcl.ac.uk.
authors.forename: Christina
authors.initials: C
authors.lastname: Dunster
authors.affiliation: MRC-PHE Centre for Environment and Health, King's College London, 150 Stamford Street, SE1 9NH London, UK; National Institute for Health Research Health Protection Research Unit in Health Impact of Environmental Hazards, King's College London, 150 Stamford Street, SE1 9NH London, UK. Electronic address: frank.kelly@kcl.ac.uk.
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Kelly
authors.affiliation: Department of Physics and Astronomy, University of Florence/INFN, 50019 Sesto Fiorentino, Italy. Electronic address: lucarelli@fi.infn.it.
authors.forename: Franco
authors.initials: F
authors.lastname: Lucarelli
authors.affiliation: Cooperative Research Centre for Environmental Sciences, Eötvös Loránd University, Pázmány Péter stny. 1/A, H-1117 Budapest, Hungary; Hungarian Satellite Trace Elements Institute to UNESCO, Pázmány Péter stny. 1/A, H-1117 Budapest, Hungary. Electronic address: zaray@chem.elte.hu.
authors.forename: Gyula
authors.initials: G
authors.lastname: Záray
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000737:chemistry*; D000397:Air Pollution / Q000706:statistics & numerical data*; D004784:Environmental Monitoring; D006814:Hungary; D010084:Oxidation-Reduction; D052638:Particulate Matter / Q000032:analysis / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter
keywords: Chemical composition; Oxidative potential; Particulate matter; Seasonal variation; Urban aerosol