Source Apportionment of Fine (PM1.8) and Ultrafine (PM0.1) Airborne Particulate Matter during a Severe Winter Pollution Episode

ArticleinEnvironmental Science and Technology 43(2):272-9 · February 2009with22 Reads
DOI: 10.1021/es800400m · Source: PubMed
Size-resolved samples of airborne particulate matter (PM) collected during a severe winter pollution episode at three sites in the San Joaquin Valley of California were extracted with organic solvents and analyzed for detailed organic compounds using GC-MS. Six particle size fractions were characterized with diameter (Dp) < 1.8 microm; the smallest size fraction was 0.056 < Dp < 0.1 microm which accounts for the majority of the mass in the ultrafine (PM0.1) size range. Source profiles for ultrafine particles developed during previous studies were applied to the measurements at each sampling site to calculate source contributions to organic carbon (OC) and elemental carbon (EC) concentrations. Ultrafine EC concentrations ranged from 0.03 microg m(-3) during the daytime to 0.18 microg m(-3) during the nighttime. Gasoline fuel, diesel fuel, and lubricating oil combustion products accounted for the majority of the ultrafine EC concentrations, with relatively minor contributions from biomass combustion and meat cooking. Ultrafine OC concentrations ranged from 0.2 microg m(-3) during the daytime to 0.8 microg m(-3) during the nighttime. Wood combustion was found to be the largest source of ultrafine OC. Meat cooking was also identified as a significant potential source of PM0.1 mass but further study is required to verify the contributions from this source. Gasoline fuel, diesel fuel, and lubricating oil combustion products made minor contributions to PM0.1 OC mass. Total ultrafine particulate matter concentrations were dominated by contributions from wood combustion and meat cooking during the current study. Future inhalation exposure studies may wish to target these sources as potential causes of adverse health effects.
    • "Cascade impactors were used to study fine particulate matter in numerous studies (Cabada et al., 2004; Chow et al., 2008; Fang et al., 2006; Huang et al., 2004; Yao et al., 2001; Keywood et al., 1999; Kleeman et al., 2008; Liu et al., 2008; Lü et al., 2012; Plaza et al., 2011; Singh et al., 2003), however only a few of them attempted to study stable carbon isotope ratio values (Cachier et al., 1985; Garbaras et al., 2009; Sang et al., 2012; Wang et al., 2012) that are a useful tool to identify the sources of particulate matter. Furthermore, δ 13 C TC values can provide a useful starting point in detecting and distinguishing carbonaceous aerosol particles. "
    [Show abstract] [Hide abstract] ABSTRACT: Abstract Carbonaceous aerosol sources were investigated by measuring the stable carbon isotope ratio (δ13CTC) in size segregated aerosol particles. The samples were collected with a micro-orifice uniform deposit impactor (MOUDI) in 11 size intervals ranging from 0.056 μm to 18 μm. The aerosol particle size distribution obtained from combined measurements with a scanning mobility particle sizer (SMPS; TSI 3936) and an aerosol particle sizer (APS; TSI 3321) is presented for comparison with MOUDI data. The analysis of δ13CTC values revealed that the total carbonaceous matter in size segregated aerosol particles significantly varied from -23.4 ± 0.1 ‰ in a coarse mode to -30.1 ± 0.5 ‰ in a fine mode. A wide range of the δ13CTC values of size segregated aerosol particles suggested various sources of aerosol particles contributing to carbonaceous particulate matter. Therefore, the source mixing equation was applied to verify the idea of mixing of two sources: continental non-fossil and fossil fuel combustion. The obtained δ13CTC value of aerosol particles originating from fossil fuel combustion was -28.0 — -28.1 ‰, while the non-fossil source δ13CTC value was in the range of -25.0 — -25.5 ‰. The two source mixing model applied to the size segregated samples revealed that the fossil fuel combustion source contributed from 100 % to 60 % to the carbonaceous particulate matter in the fine mode range (Dp < 1 μm). Meanwhile the second, continental non-fossil, source was the main contributor in the coarse fraction (Dp > 2 μm). The particle range from 0.5 to 2.0 μm was identified as a transition region where two sources almost equally contributed to carbonaceous particulate matter. The proposed mixing model offers an alternative method for determining major carbonaceous matter sources where radiocarbon analysis may lack the sensitivity (as in size segregated samples).
    Full-text · Article · May 2015
    • "Motor vehicle exhaust dominates UFP near roadsides (Riddle et al. 2008; Fruin et al. 2008 ) and in trafficintensive urban areas such as LA (Minguillón et al. 2008). Contributions from regional sources dominate UFP at locations away from roadways in regions with more typical traffic density (Kleeman et al. 2009). Traffic-generated UFP were efficiently transported to the indoor environment in Southern California (Arhami et al. 2010). "
    [Show abstract] [Hide abstract] ABSTRACT: The US Environmental Protection Agency funded five academic research centers in 2005 to address uncertainties in the health effects caused by airborne particulate matter (PM) as suggested by the 1998 National Research Council report, “Research Priorities for Airborne Particulate Matter.” The centers employed multidisciplinary teams of epidemiologists, toxicologists, atmospheric scientists, engineers, and chemists to approach four key research themes: susceptibility to PM, biological mechanisms of PM response, exposure–response relationships, and source linkages. This review presents selected accomplishments in these categories from the past 5-year period. Publications from the centers are summarized to provide both an overview of the accomplishments to date and easy reference to much of the original literature published by the centers. Numerous investigators worked together within and across centers to investigate the relationships between atmospheric PM and health effects, including (a) the role of reactive oxygen species, inflammation, the nervous system, and the cardiovascular system, (b) particle characteristics such as size, composition, source, and temporal pattern of exposure, and (c) phenotypic and genotypic characteristics of the population that influence the level of exposure and risk in response to a given exposure.
    Article · Jun 2013
    • "Therefore, the nighttime OA factor, which included a mixture of primary and secondary signatures, likely represented a mixture of primary hydrocarbons and condensed secondary biogenic SOA components formed by NO 3 oxidation. [57] The size distribution of r 2 for the COA factor peaked in 100 nm to 200 nm, a size range consistent with primarily emitted particles from meat charbroiling and frying activities [Hildemann et al., 1991; Wallace et al., 2004; Kleeman et al., 2009; Allan et al., 2010; Zhang et al., 2007], which agreed with the low O/C (0.04) for this factor. [58] Summertime measurements suggested that organic mass comprised the major component of fine aerosol particles at Bakersfield in the San Joaquin Valley. "
    [Show abstract] [Hide abstract] ABSTRACT: Secondary organic aerosols (SOA), known to form in the atmosphere from oxidation of volatile organic compounds (VOCs) emitted by anthropogenic and biogenic sources, are a poorly understood but substantial component of atmospheric particles. In this study, we examined the chemical and physical properties of SOA at Bakersfield, California, a site influenced by anthropogenic and terrestrial biogenic emissions. Factor analysis was applied to the infrared and mass spectra of fine particles to identify sources and atmospheric processing that contributed to the organic mass (OM). We found that OM accounted for 56% of submicron particle mass, with SOA components contributing 80% to 90% of OM from 15 May to 29 June 2010. SOA formed from alkane and aromatic compounds, the two major classes of vehicle-emitted hydrocarbons, accounted for 65% OM (72% SOA). The alkane and aromatic SOA components were associated with 200 nm to 500 nm accumulation mode particles, likely from condensation of daytime photochemical products of VOCs. In contrast, biogenic SOA likely formed from condensation of secondary organic vapors, produced from NO3radical oxidation reactions during nighttime hours, on 400 nm to 700 nm sized primary particles, and accounted for less than 10% OM. Local petroleum operation emissions contributed 13% to the OM, and the moderate O/C (0.2) of this factor suggested it was largely of secondary origin. Approximately 10% of organic aerosols in submicron particles were identified as either vegetative detritus (10%) or cooking activities (7%), from Fourier transform infrared spectroscopic and aerosol mass spectrometry measurements, respectively. While the mass spectra of several linearly independent SOA components were nearly identical and external source markers were needed to separate them, each component had distinct infrared spectrum, likely associated with the source-specific VOCs from which they formed.
    Full-text · Article · Dec 2012
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