Source apportionment and a novel approach of estimating regional contributions to ambient PM2.5 in Haikou, China.

PubMed

Liu, Baoshuang; Li, Tingkun; Yang, Jiamei; Wu, Jianhui; Wang, Jiao; Gao, Jixin; Bi, Xiaohui; Feng, Yinchang; Zhang, Yufen; Yang, Haihang

2017-04-01

A novel approach was developed to estimate regional contributions to ambient PM 2.5 in Haikou, China. In this paper, the investigation was divided into two main steps. The first step: analysing the characteristics of the chemical compositions of ambient PM 2.5 , as well as the source profiles, and then conducting source apportionments by using the CMB and CMB-Iteration models. The second step: the development of estimation approaches for regional contributions in terms of local features of Haikou and the results of source apportionment, and estimating regional contributions to ambient PM 2.5 in Haikou by this new approach. The results indicate that secondary sulphate, resuspended dust and vehicle exhaust were the major sources of ambient PM 2.5 in Haikou, contributing 9.9-21.4%, 10.1-19.0% and 10.5-20.2%, respectively. Regional contributions to ambient PM 2.5 in Haikou in spring, autumn and winter were 22.5%, 11.6% and 32.5%, respectively. The regional contribution in summer was assumed to be zero according to the better atmospheric quality and assumptions of this new estimation approach. The higher regional contribution in winter might be mainly attributable to the transport of polluted air originating in mainland China, especially from the north, where coal is burned for heating in winter. Copyright © 2017 Elsevier Ltd. All rights reserved.

The application of carbon-14 analyses to the source apportionment of atmospheric carbonaceous particulate matter: a review.

PubMed

Heal, Mathew R

2014-01-01

Organic carbon (OC) and elemental carbon (EC) together constitute a substantial proportion of airborne particulate matter (PM). Insight into the sources of this major contributor to PM is important for policies to mitigate the impact of PM on human health and climate change. In recent years measurement of the abundance of the radioisotope of carbon ((14)C) in samples of PM by accelerator mass spectrometry has been used to help quantify the relative contributions from sources of fossil carbon and contemporary carbon. This review provides an introduction to the different sources of carbon within PM and the role of (14)C measurements, a description of the preparation of PM samples and of the instrumentation used to quantify (14)C, and a summary of the results and source apportionment methods reported in published studies since 2004. All studies report a sizable fraction of the carbonaceous PM as of non-fossil origin. Even for PM collected in urban locations, the proportions of non-fossil carbon generally exceed 30%; typically the proportion in urban background locations is around 40-60% depending on the local influence of biomass burning. Where values have been measured directly, proportions of non-fossil carbon in EC are lower than in OC, reflecting the greater contribution of fossil-fuel combustion to EC and the generally small sources of contemporary EC. Detailed source apportionment studies point to important contributions from biogenic-derived secondary OC, consistent with other evidence of a ubiquitous presence of heavily oxidized background secondary OC. The review concludes with some comments on current issues and future prospects, including progress towards compound-class and individual-compound-specific (14)C analyses.

Source apportionment of PM2.5 organic carbon in the San Joaquin Valley using monthly and daily observations and meteorological clustering.

PubMed

Skiles, Matthew J; Lai, Alexandra M; Olson, Michael R; Schauer, James J; de Foy, Benjamin

2018-06-01

Two hundred sixty-three fine particulate matter (PM 2.5 ) samples collected on 3-day intervals over a 14-month period at two sites in the San Joaquin Valley (SJV) were analyzed for organic carbon (OC), elemental carbon (EC), water soluble organic carbon (WSOC), and organic molecular markers. A unique source profile library was applied to a chemical mass balance (CMB) source apportionment model to develop monthly and seasonally averaged source apportionment results. Five major OC sources were identified: mobile sources, biomass burning, meat smoke, vegetative detritus, and secondary organic carbon (SOC), as inferred from OC not apportioned by CMB. The SOC factor was the largest source contributor at Fresno and Bakersfield, contributing 44% and 51% of PM mass, respectively. Biomass burning was the only source with a statistically different average mass contribution (95% CI) between the two sites. Wintertime peaks of biomass burning, meat smoke, and total OC were observed at both sites, with SOC peaking during the summer months. Exceptionally strong seasonal variation in apportioned meat smoke mass could potentially be explained by oxidation of cholesterol between source and receptor and trends in wind transport outlined in a Residence Time Analysis (RTA). Fast moving nighttime winds prevalent during warmer months caused local emissions to be replaced by air mass transported from the San Francisco Bay Area, consisting of mostly diluted, oxidized concentrations of molecular markers. Good agreement was observed between SOC derived from the CMB model and from non-biomass burning WSOC mass, suggesting the CMB model is sufficiently accurate to assist in policy development. In general, uncertainty in monthly mass values derived from daily CMB apportionments were lower than that of CMB results produced with monthly marker composites, further validating daily sampling methodologies. Strong seasonal trends were observed for biomass and meat smoke OC apportionment, and monthly mass averages had lowest uncertainty when derived from daily CMB apportionments. Copyright © 2018 Elsevier Ltd. All rights reserved.

Identifying PM2.5 and PM0.1 sources for epidemiological studies in California.

PubMed

Hu, Jianlin; Zhang, Hongliang; Chen, Shuhua; Ying, Qi; Wiedinmyer, Christine; Vandenberghe, Francois; Kleeman, Michael J

2014-05-06

The University of California-Davis_Primary (UCD_P) model was applied to simultaneously track ∼ 900 source contributions to primary particulate matter (PM) in California for seven continuous years (January 1st, 2000 to December 31st, 2006). Predicted source contributions to primary PM2.5 mass, PM1.8 elemental carbon (EC), PM1.8 organic carbon (OC), PM0.1 EC, and PM0.1 OC were in general agreement with the results from previous source apportionment studies using receptor-based techniques. All sources were further subjected to a constraint check based on model performance for PM trace elemental composition. A total of 151 PM2.5 sources and 71 PM0.1 sources contained PM elements that were predicted at concentrations in general agreement with measured values at nearby monitoring sites. Significant spatial heterogeneity was predicted among the 151 PM2.5 and 71 PM0.1 source concentrations, and significantly different seasonal profiles were predicted for PM2.5 and PM0.1 in central California vs southern California. Population-weighted concentrations of PM emitted from various sources calculated using the UCD_P model spatial information differed from the central monitor estimates by up to 77% for primary PM2.5 mass and 148% for PM2.5 EC because the central monitor concentration is not representative of exposure for nearby population. The results from the UCD_P model provide enhanced source apportionment information for epidemiological studies to examine the relationship between health effects and concentrations of primary PM from individual sources.

IMPROVING PARTICULATE MATTER SOURCE APPORTIONMENT FOR HEALTH STUDIES: A TRAINED RECEPTOR MODELING APPROACH WITH SENSITIVITY, UNCERTAINTY AND SPATIAL ANALYSES

EPA Science Inventory

An approach for conducting PM source apportionment will be developed, tested, and applied that directly addresses limitations in current SA methods, in particular variability, biases, and intensive resource requirements. Uncertainties in SA results and sensitivities to SA inpu...

IMPROVING SOURCE PROFILES AND APPORTIONMENT OF COMBUSTION SOURCES USING THERMAL CARBON FRACTIONS IN MULTIVARIATE RECEPTOR MODELS

EPA Science Inventory

The purpose of this study was to improve combustion source profiles and apportionment of a PM2.5 urban aerosol by using 7 individual organic and elemental carbon thermal fractions in place of total organic and elemental carbon. This study used 3 years (96-99) of speciated data...

DEVELOPMENT OF URINARY METABOLITE BIOMARKERS TO ASSESS POPULATION EXPOSURE TO PM2.5 FROM VARIOUS COMBUSTION SOURCES

EPA Science Inventory

A primary goal of our research is to validate the use of urinary biomarkers to apportion the sources of human exposure to PM2.5. Organic source tracers have been used in source apportionment studies of ambient PM2.5 to distinguish a range of combustion sources. Both gas and par...

Establishing the origin of particulate matter across Europe

NASA Astrophysics Data System (ADS)

Schaap, Martijn; Kranenburg, Richard; Hendriks, Carlijn; Kuenen, Jeroen

2016-04-01

Exposure to particulate matter (PM) in ambient air leads to adverse health effects. To design cost effective mitigation strategies, a thorough understanding of the sources of particulate matter is crucial. In this paper we like to provide an overview of recent source apportionment studies aimed at PM and its precursors carried out at TNO. The source apportionment module that tracks the origin of modelled particulate matter distributions throughout a LOTOS-EUROS simulation will be explained. To optimally apply this technology dedicated emission inventories, e.g. fuel type specific, need to be generated. Applications to Europe shows that in northwestern Europe the contribution of transport and agricultural emissions dominate the PM mass concentrations, especially during episodic events. In eastern Europe, the domestic and energy sector are much more important. In southern Europe the picture is more mixed, although the frequent high levels of desert dust stand out. Evaluation of the source allocation against experimental data and PMF analyses is challenging as there is only a limited availability of source specific tracers or factors that can be used for direct comparison. Nonetheless, for the available tracers such as vanadium for heavy fuel oil combustion an evaluation is very well possible. The source apportionment technique can also be used to interpret particulate matter formation efficiencies. It will be shown that the conversion rates for the secondary inorganic aerosol precursors (NOx, NH3 and SO2) have changed during the last 20 years. A particular problem is related to the fact that CTMs systematically underestimate observed PM levels, which means that the contribution of certain source categories (natural, agriculture, combustion) are underestimated. Future developments needed to improve the source apportionment information concerning process knowledge, data assimilation as well as model implementation will be discussed. Specific challenges concerning the underlying emission information will be highlighted.

Source apportionment of atmospheric particulate matter (PM) using a constrained US-EPA-PMF5.0 model at different urban environments in France

NASA Astrophysics Data System (ADS)

Salameh, Dalia; Favez, Olivier; Golly, Benjamin; Besombes, Jean Luc; Alleman, Laurent; Albinet, Alexandre; Jaffrezo, Jean Luc

2017-04-01

Particulate matter (PM) is one of the most studied atmospheric pollutant in urban areas due to their adverse effects on human health (Pope et al., 2009). Intrinsic properties of PM (e.g. chemical composition and morphology) are directly linked to their origins. Therefore, a harmonized and comprehensive apportionment study of PM sources in urban environments is extremely required to connect source contributions with PM concentration levels and then develop effective PM abatement strategies. Multivariate receptor models such as Positive Matrix Factorization (PMF) are very useful and have been used worldwide for PM source apportionment (Viana et al., 2008). PMF uses a weighted least-squares fit and quantitatively determines source fingerprints (factors) and their contributions to the total PM mass. However, in many cases, it could be tricky to separate two factors that co-vary due to similar seasonal variations, making unclear the physical sense of the extracted factors. To address such issues of source collinearities, additional specific constraints are incorporated into the model (i.e., constrained PMF) based on user's external knowledge allowing better apportionment results. In this work and within the framework of the SOURCES project, a harmonized source apportionment approach has been implemented and applied for the determination of PM sources on a large number of sites (up to 20) of different typologies (e.g. urban background, industrial, traffic, rural and/or alpine sites) distributed all over France and previously investigated with annual or multiannual studies (2012-2016). A constrained PMF approach (using US-EPA PMF5.0 software) was applied to the comprehensive PM-offline chemical datasets (i.e. carbonaceous fraction, major ions, metals/trace elements, specific organic markers) in a harmonized way for all the investigated sites. Different types of specific chemical constraints from well-characterized sources were defined based on external knowledge and were imposed to some species in the PMF factor profiles. As an example, the contributions of the levoglucosan, a specific tracer of the biomass burning emissions, were pulled up maximally in the biomass burning factor profiles and were set to zero in all other resolved factors (e.g. vehicular emissions, biogenic emissions, etc,…). The different source categories contributing to ambient PM concentration levels were chemically characterized and quantified. Chemical profiles of the resolved common sources have been exploited and compared allowing us to get extra knowledge on the spatial variabilities of the source compositions. The presentation will address the main points achieved with this program. Pope, I. C., et al. (2009), New England Journal of Medicine, 360(4), 376-386. Viana, M., et al. (2008), Journal of Aerosol Science, 39(10), 827-849. Acknowledgments: This work, including a postdoctoral grant for D Salameh, is funded by the French Ministry of Environment, Energy, and Sea (MEEM) through the Environment and Energy Management Agency (ADEME, contract 1462C0044) and the national reference laboratory for air quality monitoring (LCSQA). The authors also gratefully acknowledge the funding by ANDRA of the program conducted at OPE by S Conil, and all dedicated staffs within the French regional monitoring networks for collecting the samples.

SOURCE APPORTIONMENT OF FINE PARTICLES IN THE U.S. AND ASSOCIATIONS BETWEEN INFLAMMATORY MARKER IL -8

EPA Science Inventory

Associations are well established between particulate matter (PM) and increased human mortality and morbidity. The association between PM sources and inflammatory marker IL-8 was evaluated in this study.

Sources and elemental composition of ambient PM(2.5) in three European cities.

PubMed

Vallius, M; Janssen, N A H; Heinrich, J; Hoek, G; Ruuskanen, J; Cyrys, J; Van Grieken, R; de Hartog, J J; Kreyling, W G; Pekkanen, J

2005-01-20

Source apportionment of urban fine particle mass (PM(2.5)) was performed from data collected during 1998-1999 in Amsterdam (The Netherlands), Erfurt (Germany) and Helsinki (Finland), using principal component analysis (PCA) and multiple linear regression. Six source categories of PM(2.5) were identified in Amsterdam. They were traffic-related particles (30% of the average PM(2.5)), secondary particles (34%), crustal material (7%), oil combustion (11%), industrial and incineration processes (9%), and sea salt (2%). The unidentified PM(2.5) fraction was 7% on the average. In Erfurt, four source categories were extracted with some difficulties in interpretation of source profiles. They were combustion emissions related to traffic (32%), secondary PM (32%), crustal material (21%) and industrial processes (8%). In Erfurt, 3% of PM(2.5) remained unidentified. Air pollution data and source apportionment results from the two Central European cities were compared to previously published results from Helsinki, where about 80% of average PM(2.5) was attributed to transboundary air pollution and particles from traffic and other regional combustion sources. Our results indicate that secondary particles and local combustion processes (mainly traffic) were the most important source categories in all cities; their impact on the average PM(2.5) was almost equal in Amsterdam and Erfurt whereas, in Helsinki, secondary particles made up for as much as half of the total average PM(2.5).

Defense Coastal/Estuarine Research Program (DCERP) Strategic Plan

DTIC Science & Technology

2007-09-01

atmospheric deposition. The source apportionment of nutrients from atmospheric deposition (especially nitrogen) to estuarine waters derived from direct...migrating wildlife, and nutrient release from soil weathering, atmospheric deposition represents the only source of new nutrients into the... apportionment to properly assess the contributions of off-site and on-site emission sources to regional levels of PM2.5. In preparing this DCERP Strategic

SOURCE APPORTIONMENT OF PHOENIX PM2.5 AEROSOL WITH THE UNMIX RECEPTOR MODEL

EPA Science Inventory

The multivariate receptor model Unmix has been used to analyze a 3-yr PM2.5 ambient aerosol data set collected in Phoenix, AZ, beginning in 1995. The analysis generated source profiles and overall percentage source contribution estimates (SCE) for five source categories: ga...

Inter-comparison of receptor models for PM source apportionment: Case study in an industrial area

NASA Astrophysics Data System (ADS)

Viana, M.; Pandolfi, M.; Minguillón, M. C.; Querol, X.; Alastuey, A.; Monfort, E.; Celades, I.

2008-05-01

Receptor modelling techniques are used to identify and quantify the contributions from emission sources to the levels and major and trace components of ambient particulate matter (PM). A wide variety of receptor models are currently available, and consequently the comparability between models should be evaluated if source apportionment data are to be used as input in health effects studies or mitigation plans. Three of the most widespread receptor models (principal component analysis, PCA; positive matrix factorization, PMF; chemical mass balance, CMB) were applied to a single PM10 data set (n=328 samples, 2002-2005) obtained from an industrial area in NE Spain, dedicated to ceramic production. Sensitivity and temporal trend analyses (using the Mann-Kendall test) were applied. Results evidenced the good overall performance of the three models (r2>0.83 and α>0.91×between modelled and measured PM10 mass), with a good agreement regarding source identification and high correlations between input (CMB) and output (PCA, PMF) source profiles. Larger differences were obtained regarding the quantification of source contributions (up to a factor of 4 in some cases). The combined application of different types of receptor models would solve the limitations of each of the models, by constructing a more robust solution based on their strengths. The authors suggest the combined use of factor analysis techniques (PCA, PMF) to identify and interpret emission sources, and to obtain a first quantification of their contributions to the PM mass, and the subsequent application of CMB. Further research is needed to ensure that source apportionment methods are robust enough for application to PM health effects assessments.

Chemical Composition and Source Apportionment of Size Fractionated Particulate Matter in Cleveland, Ohio, USA

EPA Science Inventory

The Cleveland airshed comprises a complex mixture of industrial source emissions that contribute to periods of non-attainment for fine particulate matter (PM 2.5 ) and are associated with increased adverse health outcomes in the exposed population. Specific PM sources responsible...

Size-resolved source apportionment of carbonaceous particulate matter in urban and rural sites in central California

NASA Astrophysics Data System (ADS)

Ham, Walter A.; Kleeman, Michael J.

2011-08-01

Very little is currently known about the relationship between exposure to different sources of ambient ultrafine particles (PM 0.1) and human health effects. If human health effects are enhanced by PM 0.1's ability to cross cell membranes, then more information is needed describing the sources of ultrafine particles that are deposited in the human respiratory system. The current study presents results for the source apportionment of airborne particulate matter in six size fractions smaller than 1.8 μm particle diameter including ultrafine particles (PM 0.1) in one of the most polluted air basins in the United States. Size-resolved source apportionment results are presented at an urban site and rural site in central California's heavily polluted San Joaquin Valley during the winter and summer months using a molecular marker chemical mass balance (MM-CMB) method. Respiratory deposition calculations for the size-resolved source apportionment results are carried out with the Multiple Path Particle Dosimetry Model ( MPPD v 2.0), including calculations for ultrafine (PM 0.1) source deposition. Diesel engines accounted for the majority of PM 0.1 and PM 1.8 EC at both the urban and rural sampling locations during both summer and winter seasons. Meat cooking accounted for 33-67% and diesel engines accounted for 15-21% of the PM 0.1 OC at Fresno. Meat cooking accounted for 22-26% of the PM 0.1 OC at the rural Westside location, while diesel engines accounted for 8-9%. Wood burning contributions to PM 0.1 OC increased to as much as 12% of PM 0.1 OC during the wintertime. The modest contribution of wood smoke reflects the success of emissions control programs over the past decade. In contrast to PM 0.1, PM 1.8 OC had a higher fraction of unidentified source contributions (68-85%) suggesting that this material is composed of secondary organic aerosol (SOA) or primary organic aerosol (POA) that has been processed by atmospheric chemical reactions. Meat cooking was the largest identified source of PM 1.8 organic carbon (OC) at the Fresno site (12-13%) while diesel engines were the largest identified PM 1.8 OC source at the rural site (5-8%). Wood burning contributions to PM 1.8 OC increased during the wintertime at both sites (6-9%) but were relatively small during the summertime (˜1%). As expected, diesel engines were the dominant source of PM 0.1 EC respiratory deposition at both the urban and rural site in both summer and winter (0.01-0.03 μg PM 0.1 EC deposited per m 3 air inhaled). Meat cooking accounted for 0.01-0.025 μg PM 0.1 OC deposited per m 3 air inhaled while diesel fuel accounted for 0.005-0.013 μg PM 0.1 OC deposited per m 3 air inhaled. Minor contributions from wood burning, motor oil, and gasoline fuel were calculated at levels <0.005 μg PM 0.1 OC deposited per m 3 air inhaled at both urban and rural locations during winter and summer seasons. If the burden of PM 0.1 deposited in the respiratory system is relevant for human health effects, then future toxicology studies should be carried out at PM 0.1 concentrations and source mixtures equivalent to those measured in the current study.

PM10 source apportionment in Milan (Italy) using time-resolved data.

PubMed

Bernardoni, Vera; Vecchi, Roberta; Valli, Gianluigi; Piazzalunga, Andrea; Fermo, Paola

2011-10-15

In this work Positive Matrix Factorization (PMF) was applied to 4-hour resolved PM10 data collected in Milan (Italy) during summer and winter 2006. PM10 characterisation included elements (Mg-Pb), main inorganic ions (NH(4)(+), NO(3)(-), SO(4)(2-)), levoglucosan and its isomers (mannosan and galactosan), and organic and elemental carbon (OC and EC). PMF resolved seven factors that were assigned to construction works, re-suspended dust, secondary sulphate, traffic, industry, secondary nitrate, and wood burning. Multi Linear Regression was applied to obtain the PM10 source apportionment. The 4-hour temporal resolution allowed the estimation of the factor contributions during peculiar episodes, which would have not been detected with the traditional 24-hour sampling strategy. Copyright © 2011 Elsevier B.V. All rights reserved.

Defense Coastal/Estuarine Research Program (DCERP) Baseline Monitoring Plan

DTIC Science & Technology

2007-09-19

climatological stress (e.g., temperature, drought) and shorter-term air pollutant stress (oxidants and metals ). Heavy metals of fine PM have been...speciation of the fine and coarse PM fractions will allow distinction between different PM sources such as wind blown soil dust, including dust...emitting 12% of the total PM2.5 mass (U.S. EPA, 2004b). Source apportionment modeling of PM2.5 mass concentrations from 24 Speciation Defense Coastal

Chemical Composition and Source Apportionment of Size ...

EPA Pesticide Factsheets

The Cleveland airshed comprises a complex mixture of industrial source emissions that contribute to periods of non-attainment for fine particulate matter (PM 2.5 ) and are associated with increased adverse health outcomes in the exposed population. Specific PM sources responsible for health effects however are not fully understood. Size-fractionated PM (coarse, fine, and ultrafine) samples were collected using a ChemVol sampler at an urban site (G.T. Craig (GTC)) and rural site (Chippewa Lake (CLM)) from July 2009 to June 2010, and then chemically analyzed. The resulting speciated PM data were apportioned by EPA positive matrix factorization to identify emission sources for each size fraction and location. For comparisons with the ChemVol results, PM samples were also collected with sequential dichotomous and passive samplers, and evaluated for source contributions to each sampling site. The ChemVol results showed that annual average concentrations of PM, elemental carbon, and inorganic elements in the coarse fraction at GTC were ~ 2, ~7, and ~3 times higher than those at CLM, respectively, while the smaller size fractions at both sites showed similar annual average concentrat ions. Seasonal variations of secondary aerosols (e.g., high N03- level in winter and high SO42- level in summer) were observed at both sites. Source apportionment results demonstrated that the PM samples at GTC and CLM were enriched with local industrial sources (e.g., steel plant and coa

Characterization and source apportionment of health risks from ambient PM10 in Hong Kong over 2000-2011

NASA Astrophysics Data System (ADS)

Li, Zhiyuan; Yuan, Zibing; Li, Ying; Lau, Alexis K. H.; Louie, Peter K. K.

2015-12-01

Atmospheric particulate matter (PM) pollution is a major public health concern in Hong Kong. In this study, the spatiotemporal variations of health risks from ambient PM10 from seven air quality monitoring stations between 2000 and 2011 were analyzed. Positive matrix factorization (PMF) was adopted to identify major source categories of ambient PM10 and quantify their contributions. Afterwards, a point-estimated risk model was used to identify the inhalation cancer and non-cancer risks of PM10 sources. The long-term trends of the health risks from classified local and non-local sources were explored. Furthermore, the reason for the increase of health risks during high PM10 days was discussed. Results show that vehicle exhaust source was the dominant inhalation cancer risk (ICR) contributor (72%), whereas trace metals and vehicle exhaust sources contributed approximately 27% and 21% of PM10 inhalation non-cancer risk (INCR), respectively. The identified local sources accounted for approximately 80% of the ICR in Hong Kong, while contribution percentages of the non-local and local sources for INCR are comparable. The clear increase of ICR at high PM days was mainly attributed to the increase of contributions from coal combustion/biomass burning and secondary sulfate, while the increase of INCR at high PM days was attributed to the increase of contributions from the sources coal combustion/biomass burning, secondary nitrate, and trace metals. This study highlights the importance of health risk-based source apportionment in air quality management with protecting human health as the ultimate target.

Chemical mass balance source apportionment of fine and PM10 in the Desert Southwest, USA

EPA Science Inventory

The Desert Southwest Coarse Particulate Matter Study was undertaken in Pinal County, Arizona, to better understand the origin and impact of sources of fine and coarse particulate matter (PM) in rural, arid regions of the U.S. southwestern desert. The desert southwest experiences ...

SOURCE APPORTIONMENT OF FINE PARTICULATE MATTER IN THE U.S. AND ASSOCIATIONS WITH LUNG INFLAMMATORY MARKERS IL -8, COX -2 AND HO -1

EPA Science Inventory

Associations are well established between particulate matter (PM) and increased human mortality and morbidity. The association between fine PM sources and lung inflammatory markers IL-8, COX-2, and HO-1 was evaluated in this study.

THE WORKSHOP ON THE SOURCE APPORTIONMENT OF PM HEALTH EFFECTS: INTER-COMPARISON OF RESULTS AND IMPLICATIONS

EPA Science Inventory

While the association between exposure to ambient fine particulate matter mass (PM2.5) and human mortality is well established, the most responsible particle types/sources are not yet certain. In May 2003, the U.S. Environmental Protection Agency's Particulate Matter Centers Prog...

Identification and chemical characterization of industrial particulate matter sources in southwest Spain.

PubMed

Alastuey, Andrés; Querol, Xavier; Plana, Feliciano; Viana, Mar; Ruiz, Carmen R; Sánchez de la Campa, Ana; de la Rosa, Jesús; Mantilla, Enrique; García dos Santos, Saul

2006-07-01

A detailed physical and chemical characterization of coarse particulate matter (PM10) and fine particulate matter (PM2.5) in the city of Huelva (in Southwestern Spain) was carried out during 2001 and 2002. To identify the major emission sources with a significant influence on PM10 and PM2.5, a methodology was developed based on the combination of: (1) real-time measurements of levels of PM10, PM2.5, and very fine particulate matter (PM1); (2) chemical characterization and source apportionment analysis of PM10 and PM2.5; and (3) intensive measurements in field campaigns to characterize the emission plumes of several point sources. Annual means of 37, 19, and 16 microg/m3 were obtained for the study period for PM10, PM2.5, and PM1, respectively. High PM episodes, characterized by a very fine grain size distribution, are frequently detected in Huelva mainly in the winter as the result of the impact of the industrial emission plumes on the city. Chemical analysis showed that PM at Huelva is characterized by high PO4(3-) and As levels, as expected from the industrial activities. Source apportionment analyses identified a crustal source (36% of PM10 and 31% of PM2.5); a traffic-related source (33% of PM10 and 29% of PM2.5), and a marine aerosol contribution (only in PM10, 4%). In addition, two industrial emission sources were identified in PM10 and PM2.5: (1) a petrochemical source, 13% in PM10 and 8% in PM2.5; and (2) a mixed metallurgical-phosphate source, which accounts for 11-12% of PM10 and PM2.5. In PM2.5 a secondary source has been also identified, which contributed to 17% of the mass. A complete characterization of industrial emission plumes during their impact on the ground allowed for the identification of tracer species for specific point sources, such as petrochemical, metallurgic, and fertilizer and phosphate production industries.

Investigating the contribution of shipping emissions to atmospheric PM2.5 using a combined source apportionment approach.

PubMed

Lang, Jianlei; Zhou, Ying; Chen, Dongsheng; Xing, Xiaofan; Wei, Lin; Wang, Xiaotong; Zhao, Na; Zhang, Yanyun; Guo, Xiurui; Han, Lihui; Cheng, Shuiyuan

2017-10-01

Many studies have been conducted focusing on the contribution of land emission sources to PM 2.5 in China; however, little attention had been paid to other contributions, especially the secondary contributions from shipping emissions to atmospheric PM 2.5 . In this study, a combined source apportionment approach, including principle component analysis (PCA) and WRF-CMAQ simulation, was applied to identify both primary and secondary contributions from ships to atmospheric PM 2.5 . An intensive PM 2.5 observation was conducted from April 2014 to January 2015 in Qinhuangdao, which was close to the largest energy output port of China. The chemical components analysis results showed that the primary component was the major contributor to PM 2.5 , with proportions of 48.3%, 48.9%, 55.1% and 55.4% in spring, summer, autumn and winter, respectively. The secondary component contributed higher fractions in summer (48.2%) and winter (36.8%), but had lower percentages in spring (30.1%) and autumn (32.7%). The hybrid source apportionment results indicated that the secondary contribution (SC) of shipping emissions to PM 2.5 could not be ignored. The annual average SC was 2.7%, which was comparable to the primary contribution (2.9%). The SC was higher in summer (5.3%), but lower in winter (1.1%). The primary contributions to atmospheric PM 2.5 were 3.0%, 2.5%, 3.4% and 2.7% in spring, summer, autumn and winter, respectively. As for the detailed chemical components, the contributions of shipping emissions were 2.3%, 0.5%, 0.1%, 1.0%, 1.7% and 0.1% to elements & sea salt, primary organic aerosol (POA), element carbon (EC), nitrate, sulfate and secondary organic carbon (SOA), respectively. The results of this study will further the understanding of the implications of shipping emissions in PM 2.5 pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

77 FR 4510 - Air Quality Implementation Plans; Kentucky; Attainment Plan for the Kentucky Portion of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-30

... and population based apportionment of the area and nonroad sectors to support the mobile source... and nitrogen oxides (NO X ) for the mobile source contribution to ambient PM 2.5 levels for the.... Attainment Date B. Insignificance Determination for the Mobile Source Contribution to PM 2.5 and NO X...

SOURCE APPORTIONMENT OF PM2.5 AT AN URBAN IMPROVE SITE IN SEATTLE, WA

EPA Science Inventory

The multivariate receptor models Positive Matrix Factorization (PMF) and Unmix were used along with EPA's Chemical Mass Balance model to deduce the sources of PM2.5 at a centrally located urban site in Seattle, Washington. A total of 289 filter samples were obtained with an IM...

Identification of biased sectors in emission data using a combination of chemical transport model and receptor model

NASA Astrophysics Data System (ADS)

Uranishi, Katsushige; Ikemori, Fumikazu; Nakatsubo, Ryohei; Shimadera, Hikari; Kondo, Akira; Kikutani, Yuki; Asano, Katsuyoshi; Sugata, Seiji

2017-10-01

This study presented a comparison approach with multiple source apportionment methods to identify which sectors of emission data have large biases. The source apportionment methods for the comparison approach included both receptor and chemical transport models, which are widely used to quantify the impacts of emission sources on fine particulate matter of less than 2.5 μm in diameter (PM2.5). We used daily chemical component concentration data in the year 2013, including data for water-soluble ions, elements, and carbonaceous species of PM2.5 at 11 sites in the Kinki-Tokai district in Japan in order to apply the Positive Matrix Factorization (PMF) model for the source apportionment. Seven PMF factors of PM2.5 were identified with the temporal and spatial variation patterns and also retained features of the sites. These factors comprised two types of secondary sulfate, road transportation, heavy oil combustion by ships, biomass burning, secondary nitrate, and soil and industrial dust, accounting for 46%, 17%, 7%, 14%, 13%, and 3% of the PM2.5, respectively. The multiple-site data enabled a comprehensive identification of the PM2.5 sources. For the same period, source contributions were estimated by air quality simulations using the Community Multiscale Air Quality model (CMAQ) with the brute-force method (BFM) for four source categories. Both models provided consistent results for the following three of the four source categories: secondary sulfates, road transportation, and heavy oil combustion sources. For these three target categories, the models' agreement was supported by the small differences and high correlations between the CMAQ/BFM- and PMF-estimated source contributions to the concentrations of PM2.5, SO42-, and EC. In contrast, contributions of the biomass burning sources apportioned by CMAQ/BFM were much lower than and little correlated with those captured by the PMF model, indicating large uncertainties in the biomass burning emissions used in the CMAQ simulations. Thus, this comparison approach using the two antithetical models enables us to identify which sectors of emission data have large biases for improvement of future air quality simulations.

Receptor model-based source apportionment of particulate pollution in Hyderabad, India.

PubMed

Guttikunda, Sarath K; Kopakka, Ramani V; Dasari, Prasad; Gertler, Alan W

2013-07-01

Air quality in Hyderabad, India, often exceeds the national ambient air quality standards, especially for particulate matter (PM), which, in 2010, averaged 82.2 ± 24.6, 96.2 ± 12.1, and 64.3 ± 21.2 μg/m(3) of PM10, at commercial, industrial, and residential monitoring stations, respectively, exceeding the national ambient standard of 60 μg/m(3). In 2005, following an ordinance passed by the Supreme Court of India, a source apportionment study was conducted to quantify source contributions to PM pollution in Hyderabad, using the chemical mass balance (version 8.2) receptor model for 180 ambient samples collected at three stations for PM10 and PM2.5 size fractions for three seasons. The receptor modeling results indicated that the PM10 pollution is dominated by the direct vehicular exhaust and road dust (more than 60%). PM2.5 with higher propensity to enter the human respiratory tracks, has mixed sources of vehicle exhaust, industrial coal combustion, garbage burning, and secondary PM. In order to improve the air quality in the city, these findings demonstrate the need to control emissions from all known sources and particularly focus on the low-hanging fruits like road dust and waste burning, while the technological and institutional advancements in the transport and industrial sectors are bound to enhance efficiencies. Andhra Pradesh Pollution Control Board utilized these results to prepare an air pollution control action plan for the city.

Sources of particulate matter in China: Insights from source apportionment studies published in 1987-2017.

PubMed

Zhu, Yanhong; Huang, Lin; Li, Jingyi; Ying, Qi; Zhang, Hongliang; Liu, Xingang; Liao, Hong; Li, Nan; Liu, Zhenxin; Mao, Yuhao; Fang, Hao; Hu, Jianlin

2018-06-01

Particulate matter (PM) in the atmosphere has adverse effects on human health, ecosystems, and visibility. It also plays an important role in meteorology and climate change. A good understanding of its sources is essential for effective emission controls to reduce PM and to protect public health. In this study, a total of 239 PM source apportionment studies in China published during 1987-2017 were reviewed. The documents studied include peer-reviewed papers in international and Chinese journals, as well as degree dissertations. The methods applied in these studies were summarized and the main sources in various regions of China were identified. The trends of source contributions at two major cities with abundant studies over long-time periods were analyzed. The most frequently used methods for PM source apportionment in China are receptor models, including chemical mass balance (CMB), positive matrix factorization (PMF), and principle component analysis (PCA). Dust, fossil fuel combustion, transportation, biomass burning, industrial emission, secondary inorganic aerosol (SIA) and secondary organic aerosol (SOA) are the main source categories of fine PM identified in China. Even though the sources of PM vary among seven different geographical areas of China, SIA, industrial, and dust emissions are generally found to be the top three source categories in 2007-2016. A number of studies investigated the sources of SIA and SOA in China using air quality models and indicated that fossil fuel combustion and industrial emissions were the most important sources of SIA (total contributing 63.5%-88.1% of SO 4 2- , and 47.3%-70% NO 3 - ), and agriculture emissions were the dominant source of NH 4 + (contributing 53.9%-90%). Biogenic emissions were the most important source of SOA in China in summer, while residential and industrial emissions were important in winter. Long-term changes of PM sources at two megacities of Beijing and Nanjing indicated that the contributions of fossil fuel and industrial sources have been declining after stricter emission controls in recent years. In general, dust and industrial contributions decreased and transportation contributions increased after 2000. PM 2.5 emissions are predicted to decline in most regions during 2005-2030, even though the energy consumptions except biomass burning are predicted to continue to increase. Industrial, residential, and biomass burning sources will become more important in the future in the businuess-as-usual senarios. This review provides valuable information about main sources of PM and their trends in China. A few recommendations are suggested to further improve our understanding the sources and to develop effective PM control strategies in various regions of China. Copyright © 2018 Elsevier Ltd. All rights reserved.

SOURCE APPORTIONMENT OF PM2.5 IN SEATTLE, WA URBAN IMPROVE SITE: COMPARISON OF THREE RECEPTOR MODELS AND SOURCE PROFILES

EPA Science Inventory

IMPROVE protocol data were collected at the urban Beacon Hill monitoring site in Seattle, WA from 1996-99. The 289 sets of PM2.5 filters were analyzed for: metals using PIXIE and XRF, anions using ion chromatography, elemental hydrogen (H) by proton scattering, and elemental an...

FORT HALL SOURCE APPORTIONMENT STUDY (FINAL REPORT)

EPA Science Inventory

Air quality monitoring on the Fort Hall Indian Reservation has revealed numerous exceedances of the National Ambient Air Quality Standard (NAAQS) for 24-h averaged PM10 mass. Wind-directional analysis coupled with PM10 measurements have identified the FMC elemental phosphorus p...

Determining the contribution of long-range transport, regional and local source areas, to PM10 mass loading in Hessen, Germany using a novel multi-receptor based statistical approach

NASA Astrophysics Data System (ADS)

Garg, Saryu; Sinha, Baerbel

2017-10-01

This study uses two newly developed statistical source apportionment models, MuSAM and MuReSAM, to perform quantitative statistical source apportionment of PM10 at multiple receptor sites in South Hessen. MuSAM uses multi-site back trajectory data to quantify the contribution of long-range transport, while MuReSAM uses wind speed and direction as proxy for regional transport and quantifies the contribution of regional source areas. On average, between 7.8 and 9.1 μg/m3 of PM10 (∼50%) at receptor sites in South Hessen is contributed by long-range transport. The dominant source regions are Eastern, South Eastern, and Southern Europe. 32% of the PM10 at receptor sites in South Hessen is contributed by regional source areas (2.8-9.41 μg/m3). This fraction varies from <20% at remote sites to >40% for urban stations. Sources located within a 2 km radius around the receptor site are responsible for 7%-20% of the total PM10 mass (0.7-4.4 μg/m3). The perturbation study of the traffic flow due to the closing and reopening of the Schiersteiner Brücke revealed that the contribution of the bridge to PM10 mass loadings at two nearby receptor sites increased by approximately 120% after it reopened and became a bottleneck, although in absolute terms, the increase is small.

Chemical composition and source apportionment of size fractionated particulate matter in Cleveland, Ohio, USA.

PubMed

Kim, Yong Ho; Krantz, Q Todd; McGee, John; Kovalcik, Kasey D; Duvall, Rachelle M; Willis, Robert D; Kamal, Ali S; Landis, Matthew S; Norris, Gary A; Gilmour, M Ian

2016-11-01

The Cleveland airshed comprises a complex mixture of industrial source emissions that contribute to periods of non-attainment for fine particulate matter (PM 2.5 ) and are associated with increased adverse health outcomes in the exposed population. Specific PM sources responsible for health effects however are not fully understood. Size-fractionated PM (coarse, fine, and ultrafine) samples were collected using a ChemVol sampler at an urban site (G.T. Craig (GTC)) and rural site (Chippewa Lake (CLM)) from July 2009 to June 2010, and then chemically analyzed. The resulting speciated PM data were apportioned by EPA positive matrix factorization to identify emission sources for each size fraction and location. For comparisons with the ChemVol results, PM samples were also collected with sequential dichotomous and passive samplers, and evaluated for source contributions to each sampling site. The ChemVol results showed that annual average concentrations of PM, elemental carbon, and inorganic elements in the coarse fraction at GTC were ∼2, ∼7, and ∼3 times higher than those at CLM, respectively, while the smaller size fractions at both sites showed similar annual average concentrations. Seasonal variations of secondary aerosols (e.g., high NO 3 - level in winter and high SO 4 2- level in summer) were observed at both sites. Source apportionment results demonstrated that the PM samples at GTC and CLM were enriched with local industrial sources (e.g., steel plant and coal-fired power plant) but their contributions were influenced by meteorological conditions and the emission source's operation conditions. Taken together the year-long PM collection and data analysis provides valuable insights into the characteristics and sources of PM impacting the Cleveland airshed in both the urban center and the rural upwind background locations. These data will be used to classify the PM samples for toxicology studies to determine which PM sources, species, and size fractions are of greatest health concern. Copyright © 2016 Elsevier Ltd. All rights reserved.

Source Contributions of Urban PM2.5 in the Beijing-Tianjin-Hebei Region: Changes between 2006 and 2013 and Relative Impacts of Emissions and Meteorology

NASA Astrophysics Data System (ADS)

Li, X.; Zhang, Q.; Zhang, Y.; Zheng, B.; Li, M.; Wang, K.; Chen, Y.; Wallington, T. J.; Han, W.; Shen, W.; Zhang, X.; He, K.

2015-12-01

Anthropogenic emissions in China have been controlled for years to improve ambient air quality. However, severe haze events caused by atmospheric aerosols with aerodynamic diameter less than or equal to 2.5 μm (PM2.5) have continued to occur, especially in the Beijing-Tianjin-Hebei (BTH) region. The Chinese government has set an ambitious goal to reduce urban PM2.5 concentrations by 25% in BTH by 2017 relative to the 2012 levels. Source apportionment (SA) is necessary to the development of the effective emission control strategies. In this work, the Comprehensive Air Quality Model with extensions (CAMx) with the Particulate Source Apportionment Technology (PSAT) is applied to the China domain for the years 2006 and 2013. Ambient surface concentrations of PM2.5 and its components are generally well reproduced. To quantify the contributions of each emission category or region to PM2.5 in BTH, the total emissions are divided into 7 emission categories and 11 source regions. The source contributions determined in this work are generally consistent with results from previous work. In 2013, the industrial (44%) and residential (27%) sectors are the dominant contributors to urban PM2.5 in BTH. The residential sector is the largest contributor in winter; the industry sector dominates in other seasons. A slight increasing trend (+3% for industry and +6% for residential) is found in 2013 relative to 2006, necessitating more attention to these two sectors. Local emissions make the largest contribution (40%-60%) for all receptors. Change of source contribution of PM2.5 in Beijing and northern Hebei are dominate by change of local emission. However, for Tianjin, and central and southern Hebei, change of meteorology condition are as important as change of emission, because regional inflow in these areas is more important than in Beijing and northern Hebei and can increase under unfavorable weather conditions, indicating a strong need for regional joint emission control efforts. The results in this study enhance the quantitative understanding of the source-receptor relationships and provide an important basis for policymaking to advance the control of PM2.5 pollution in China. Both sector-based and fuel-based source apportionment will be available to further improve the comparability with receptor model results.

Source Apportionment of Ambient Fine Particulate Matter in Dearborn, Michigan, using Hourly Resolved PM Chemical Composition Data

EPA Science Inventory

High time-resolution aerosol sampling was conducted for one month during July–August 2007 in Dearborn, MI, a non-attainment area for fine particulate matter (PM2.5) National Ambient Air Quality Standards (NAAQS). Measurements of more than 30 PM2.5 species were made using a suite o...

An inter-comparison of PM10 source apportionment using PCA and PMF receptor models in three European sites.

PubMed

Cesari, Daniela; Amato, F; Pandolfi, M; Alastuey, A; Querol, X; Contini, D

2016-08-01

Source apportionment of aerosol is an important approach to investigate aerosol formation and transformation processes as well as to assess appropriate mitigation strategies and to investigate causes of non-compliance with air quality standards (Directive 2008/50/CE). Receptor models (RMs) based on chemical composition of aerosol measured at specific sites are a useful, and widely used, tool to perform source apportionment. However, an analysis of available studies in the scientific literature reveals heterogeneities in the approaches used, in terms of "working variables" such as the number of samples in the dataset and the number of chemical species used as well as in the modeling tools used. In this work, an inter-comparison of PM10 source apportionment results obtained at three European measurement sites is presented, using two receptor models: principal component analysis coupled with multi-linear regression analysis (PCA-MLRA) and positive matrix factorization (PMF). The inter-comparison focuses on source identification, quantification of source contribution to PM10, robustness of the results, and how these are influenced by the number of chemical species available in the datasets. Results show very similar component/factor profiles identified by PCA and PMF, with some discrepancies in the number of factors. The PMF model appears to be more suitable to separate secondary sulfate and secondary nitrate with respect to PCA at least in the datasets analyzed. Further, some difficulties have been observed with PCA in separating industrial and heavy oil combustion contributions. Commonly at all sites, the crustal contributions found with PCA were larger than those found with PMF, and the secondary inorganic aerosol contributions found by PCA were lower than those found by PMF. Site-dependent differences were also observed for traffic and marine contributions. The inter-comparison of source apportionment performed on complete datasets (using the full range of available chemical species) and incomplete datasets (with reduced number of chemical species) allowed to investigate the sensitivity of source apportionment (SA) results to the working variables used in the RMs. Results show that, at both sites, the profiles and the contributions of the different sources calculated with PMF are comparable within the estimated uncertainties indicating a good stability and robustness of PMF results. In contrast, PCA outputs are more sensitive to the chemical species present in the datasets. In PCA, the crustal contributions are higher in the incomplete datasets and the traffic contributions are significantly lower for incomplete datasets.

Identification and characterization of fine and coarse particulate matter sources in a middle-European urban environment

NASA Astrophysics Data System (ADS)

Kertész, Zs.; Szoboszlai, Z.; Angyal, A.; Dobos, E.; Borbély-Kiss, I.

2010-06-01

In this work a source apportionment study is presented which aimed to characterize the PM 2.5 and PM 2.5-10 sources in the urban area of Debrecen, East-Hungary by using streaker samples, IBA methods and positive matrix factorization (PMF) analysis. Samples of fine (PM 2.5) and coarse (PM 2.5-10) urban particulate matter were collected with 2 h time resolution in the frame of five sampling campaigns during 2007-2009 in different seasons in the downtown of Debrecen. Elemental concentrations from Al to Pb of over 1000 samples were obtained by particle induced X-ray emission (PIXE); concentrations of black carbon (BC) were determined with a smoke stain reflectometer. On this data base source apportionment was carried out by using the PMF method. Seven factors were identified for both size fractions, including soil dust, traffic, secondary aerosol - sulphates, domestic heating, oil combustion, agriculture and an unknown factor enriched with chlorine. Seasonal and daily variation of the different factors was studied as well as their dependence on meteorological parameters. Besides determining the time patterns characteristic to the city, several emission episodes were identified including a Saharan dust intrusion on 21st-24th May, 2008.

GUIDELINES FOR THE APPLICATION OF SEM/EDX ANALYTICAL TECHNIQUES FOR FINE AND COARSE PM SAMPLES

EPA Science Inventory

Scanning Electron Microscopy (SEM) coupled with Energy-Dispersive X-ray analysis (EDX) is a powerful tool in the characterization and source apportionment of environmental particulate matter (PM), providing size, chemistry, and morphology of particles as small as a few tenths ...

Comparison of receptor models for source apportionment of the PM10 in Zaragoza (Spain).

PubMed

Callén, M S; de la Cruz, M T; López, J M; Navarro, M V; Mastral, A M

2009-08-01

Receptor models are useful to understand the chemical and physical characteristics of air pollutants by identifying their sources and by estimating contributions of each source to receptor concentrations. In this work, three receptor models based on principal component analysis with absolute principal component scores (PCA-APCS), Unmix and positive matrix factorization (PMF) were applied to study for the first time the apportionment of the airborne particulate matter less or equal than 10microm (PM10) in Zaragoza, Spain, during 1year sampling campaign (2003-2004). The PM10 samples were characterized regarding their concentrations in inorganic components: trace elements and ions and also organic components: polycyclic aromatic hydrocarbons (PAH) not only in the solid phase but also in the gas phase. A comparison of the three receptor models was carried out in order to do a more robust characterization of the PM10. The three models predicted that the major sources of PM10 in Zaragoza were related to natural sources (60%, 75% and 47%, respectively, for PCA-APCS, Unmix and PMF) although anthropogenic sources also contributed to PM10 (28%, 25% and 39%). With regard to the anthropogenic sources, while PCA and PMF allowed high discrimination in the sources identification associated with different combustion sources such as traffic and industry, fossil fuel, biomass and fuel-oil combustion, heavy traffic and evaporative emissions, the Unmix model only allowed the identification of industry and traffic emissions, evaporative emissions and heavy-duty vehicles. The three models provided good correlations between the experimental and modelled PM10 concentrations with major precision and the closest agreement between the PMF and PCA models.

Implementation and evaluation of PM2.5 source contribution analysis in a photochemical model

EPA Science Inventory

Source culpability assessments are useful for developing effective emissions control programs. The Integrated Source Apportionment Method (ISAM) has been implemented in the Community Multiscale Air Quality (CMAQ) model to track contributions from source groups and regions to ambi...

Source apportionment of population representative samples of PM(2.5) in three European cities using structural equation modelling.

PubMed

Ilacqua, Vito; Hänninen, Otto; Saarela, Kristina; Katsouyanni, Klea; Künzli, Nino; Jantunen, Matti

2007-10-01

Apportionment of urban particulate matter (PM) to sources is central for air quality management and efficient reduction of the substantial public health risks associated with fine particles (PM(2.5)). Traffic is an important source combustion particles, but also a significant source of resuspended particles that chemically resemble Earth's crust and that are not affected by development of cleaner motor technologies. A substantial fraction of urban ambient PM originates from long-range transport outside the immediate urban environment including secondary particles formed from gaseous emissions of mainly sulphur, nitrogen oxides and ammonia. Most source apportionment studies are based on small number of fixed monitoring sites and capture well population exposures to regional and long-range transported particles. However, concentrations from local sources are very unevenly distributed and the results from such studies are therefore poorly representative of the actual exposures. The current study uses PM(2.5) data observed at population based random sampled residential locations in Athens, Basle and Helsinki with 17 elemental constituents, selected VOCs (xylenes, trimethylbenzenes, nonane and benzene) and light absorbance (black smoke). The major sources identified across the three cities included crustal, salt, long-range transported inorganic and traffic sources. Traffic was associated separately with source categories with crustal (especially Athens and Helsinki) and long-range transported chemical composition (all cities). Remarkably high fractions of the variability of elemental (R(2)>0.6 except for Ca in Basle 0.38) and chemical concentrations (R(2)>0.5 except benzene in Basle 0.22 and nonane in Athens 0.39) are explained by the source factors of an SEM model. The RAINS model that is currently used as the main tool in developing European air quality management policies seems to capture the local urban fraction (the city delta term) quite well, but underestimates crustal particle levels in the three cities of the current study. Utilizing structural equation modelling parallel with traditional principal component analysis (PCA) provides an objective method to determine the number of factors to be retained in a model and allows for formal hypotheses testing.

Wood burning pollution in southern Chile: PM2.5 source apportionment using CMB and molecular markers.

PubMed

Villalobos, Ana M; Barraza, Francisco; Jorquera, Héctor; Schauer, James J

2017-06-01

Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; i.e., ambient 24-h PM 2.5 concentrations have exceeded 150 μg/m 3 in the winter season and the top concentration reached 372 μg/m 3 in 2010. Annual mean concentrations have decreased but are still above 30 μg/m 3 . For the very first time, a molecular marker source apportionment of ambient organic carbon (OC) and PM 2.5 was conducted in Temuco. Primary resolved sources for PM 2.5 were wood smoke (37.5%), coal combustion (4.4%), diesel vehicles (3.3%), dust (2.2%) and vegetative detritus (0.7%). Secondary inorganic PM 2.5 (sulfates, nitrates and ammonium) contributed 4.8% and unresolved organic aerosols (generated from volatile emissions from incomplete wood combustion), including secondary organic aerosols, contributed 47.1%. Adding the contributions of unresolved organic aerosols to those from primary wood smoke implies that wood burning is responsible for 84.6% of the ambient PM 2.5 in Temuco. This predominance of wood smoke is ultimately due to widespread poverty and a lack of efficient household heating methods. The government has been implementing emission abatement policies but achieving compliance with ambient air quality standards for PM 2.5 in southern Chile remains a challenge. Copyright © 2017 Elsevier Ltd. All rights reserved.

Source apportionment of PM2.5 carbonaceous aerosol in Baghdad, Iraq

NASA Astrophysics Data System (ADS)

Hamad, Samera Hussein; Schauer, James Jay; Heo, Jongbae; Kadhim, Ahmed K. H.

2015-04-01

Baghdad is the second largest city in the Middle East and suffers from severe air quality degradation due to the high levels of the atmospheric particulate matter (PM). Limited information exists regarding the sources of PM in Baghdad, and the lack of information on sources inhibits the development of control strategies to reduce air pollution. To better understand the nature of fine particulate matter (PM2.5) in Baghdad and the Middle East, a one year sampling campaign to collect PM2.5 was conducted from September 2012 through September 2013, missing August 2013 samples due to the security situation. 24-hour integrated samples collected on a 1-in-6 day schedule were analyzed for the major components, and monthly average samples were analyzed by gas chromatography mass spectrometry (GCMS) methods to measure particle-phase organic molecular markers. The results of organic molecular markers were used in a chemical mass balance (CMB) model to quantify the sources of PM2.5 organic carbon (OC) and PM2.5 mass. Primary sources accounted for 44% of the measured PM2.5, and secondary sources were estimated to make up 28% of the measured PM2.5. Picene, a tracer of coal combustion detected in Baghdad where there is no evidence for coal combustion, can be attributed to burning crude oil and other low quality fuels in Baghdad. Source apportionment results showed that the dominant sources of the carbonaceous aerosols in Baghdad are gasoline (37 ± 6%) and diesel engines (17 ± 3%) which can be attributed to the extensive use of gasoline and diesel powered generators in Baghdad. Wood burning and residual oil combustion contributed to 5 ± 0.4 and 1 ± 0.2% respectively of OC. The unresolved sources contributed to 42 ± 19% of the OC which represented the secondary organic aerosol (SOA) and the unidentified sources.

Urban PM in Eastern Germany: Source apportionment and contributions from different spatial scales

NASA Astrophysics Data System (ADS)

van Pinxteren, D.; Fomba, K. W.; Mothes, F.; Spindler, G.; Herrmann, H.

2017-12-01

Understanding the contributions of particulate matter (PM) sources and the source areas impacting total PM levels in a city are important requirements for further developing clean air policies and efficient abatement strategies. This presentation reports on two studies in Eastern Germany providing a detailed picture of present-day urban PM sources and discriminating contributions of local, regional and long-range sources. The "Leipzig Aerosol 2013-15" study yielded contributions of 12 sources to coarse, fine, and ultrafine particles, resolved by Positive Matrix Factorization (PMF) from comprehensive chemical speciation of 5-stage Berner impactor samples at 4 different sites in the Leipzig area. Dominant winter-time sources were traffic exhaust and non-exhaust emissions, secondary aerosol formation, and combustion emissions from both biomass and coal burning with different relative importance in different particle size ranges. Local sources dominated PM levels in ultrafine and coarse particles (60% - 80%) while high mass concentrations in accumulation mode particles mainly resulted from regional import into the city (70%). The "PM-East" study compiled PM10 mass and constituents' concentrations at 10 urban and rural sites in Eastern Germany during winter 2016/17, which included a 3-week episode of frequent exceedances of the PM10 limit value. PMF source apportionment is performed for a subset of the sites, including the city of Berlin. Contributions from short-, mid-, and long-range sources, including trans-boundary pollution import from neighbouring countries, are quantitatively assessed by advanced back trajectory statistical methods. Data analysis in PM-East is ongoing and final results will be available by November. Funding is acknowledged from 4 federal states of Germany: Berlin Senate Department for Environment, Transport and Climate Protection; Saxon State Office for Environment, Agriculture and Geology; State Agency for Environment, Nature Conservation and Geology Mecklenburg-Vorpommern; and Brandenburg State Office for Environment.

Chemical characteristics and source apportionment of fine particulate organic carbon in Hong Kong during high particulate matter episodes in winter 2003

NASA Astrophysics Data System (ADS)

Li, Yun-Chun; Yu, Jian Zhen; Ho, Steven Sai Hang; Schauer, James J.; Yuan, Zibing; Lau, Alexis K. H.; Louie, Peter K. K.

2013-02-01

PM2.5 samples were collected at six general stations and one roadside station in Hong Kong in two periods of high particulate matter (PM) in 2003 (27 October-4 November and 30 November-13 December). The highest PM2.5 reached 216 μg m- 3 during the first high PM period and 113 μg m- 3 during the second high PM period. Analysis of synoptic weather conditions identified individual sampling days under dominant influence of one of three types of air masses, that is, local, regional and long-range transported (LRT) air masses. Roadside samples were discussed separately due to heavy influences from vehicular emissions. This research examines source apportionment of fine organic carbon (OC) and contribution of secondary organic aerosol on high PM days under different synoptic conditions. Six primary OC (POC) sources (vehicle exhaust, biomass burning, cooking, cigarette smoke, vegetative detritus, and coal combustion) were identified on the basis of characteristic organic tracers. Individual POC source contributions were estimated using chemical mass balance model. In the roadside and the local samples, OC was dominated by the primary sources, accounting for more than 74% of OC. In the samples influenced by regional and LRT air masses, secondary OC (SOC), which was approximated to be the difference between the total measured OC and the apportioned POC, contributed more than 54% of fine OC. SOC was highly correlated with water-soluble organic carbon and sulfate, consistent with its secondary nature.

Daily trends and source apportionment of ultrafine particulate mass (PM0.1) over an annual cycle in a typical California city.

PubMed

Kuwayama, Toshihiro; Ruehl, Chris R; Kleeman, Michael J

2013-12-17

Toxicology studies indicate that inhalation of ultrafine particles (Dp < 0.1 μm) causes adverse health effects, presumably due to their large surface area-to-volume ratio that can drive heterogeneous reactions. Epidemiological associations between ultrafine particles and health effects, however, have been difficult to identify due to the lack of appropriate long-term monitoring and exposure data. The majority of the existing ultrafine particle epidemiology studies are based on exposure to particle number, although an independent analysis suggests that ultrafine particle mass (PM0.1) correlates better with particle surface area. More information is needed to characterize PM0.1 exposure to fully evaluate the health effects of ultrafine particles using epidemiology. The present study summarizes 1 year of daily PM0.1 chemistry and source apportionment at Sacramento, CA, USA. Positive matrix factorization (PMF) was used to resolve PM0.1 source contributions from old-technology diesel engines, residential wood burning, rail, regional traffic, and brake wear/road dust. Diesel PM0.1 and total PM0.1 concentrations were reduced by 97 and 26%, respectively, as a result of the adoption of cleaner diesel technology. The strong linear correlation between PM0.1 and particle surface area in central California suggests that the adoption of clean diesel engines reduced particle surface area by similar amounts. PM0.1 sulfate reduction occurred as a result of reduced primary particle surface area available for sulfate condensation. The current study demonstrates the capability of measuring PM0.1 source contributions over a 12 month period and identifies the extended benefits of emissions reduction efforts for diesel engines on ambient concentrations of primary and secondary PM0.1.

Source apportionment of PM10 and PM2.5 air pollution, and possible impacts of study characteristics in South Korea.

PubMed

Ryou, Hyoung Gon; Heo, Jongbae; Kim, Sun-Young

2018-09-01

Studies of source apportionment (SA) for particulate matter (PM) air pollution have enhanced understanding of dominant pollution sources and quantification of their contribution. Although there have been many SA studies in South Korea over the last two decades, few studies provided an integrated understanding of PM sources nationwide. The aim of this study was to summarize findings of PM SA studies of South Korea and to explore study characteristics. We selected studies that estimated sources of PM 10 and PM 2.5 performed for 2000-2017 in South Korea using Positive Matrix Factorization and Chemical Mass Balance. We reclassified the original PM sources identified in each study into seven categories: motor vehicle, secondary aerosol, soil dust, biomass/field burning, combustion/industry, natural source, and others. These seven source categories were summarized by using frequency and contribution across four regions, defined by northwest, west, southeast, and southwest regions, by PM 10 and PM 2.5 . We also computed the population-weighted mean contribution of each source category. In addition, we compared study features including sampling design, sampling and lab analysis methods, chemical components, and the inclusion of Asian dust days. In the 21 selected studies, all six PM 10 studies identified motor vehicle, soil dust, and combustion/industry, while all 15 PM 2.5 studies identified motor vehicle and soil dust. Different from the frequency, secondary aerosol produced a large contribution to both PM 10 and PM 2.5 . Motor vehicle contributed highly to both, whereas the contribution of combustion/industry was high for PM 10 . The population-weighted mean contribution was the highest for the motor vehicle and secondary aerosol sources for both PM10 and PM2.5. However, these results were based on different subsets of chemical speciation data collected at a single sampling site, commonly in metropolitan areas, with short overlap and measured by different lab analysis methods. We found that motor vehicle and secondary aerosol were the most common and influential sources for PM in South Korea. Our study, however, suggested a caution to understand SA findings from heterogeneous study features for study designs and input data. Copyright © 2018. Published by Elsevier Ltd.

Fine Particulate Pollution and Source Apportionment in the Urban Centers for Africa, Asia and Latin America

NASA Astrophysics Data System (ADS)

Guttikunda, S. K.; Johnson, T. M.; Procee, P.

2004-12-01

Fossil fuel combustion for domestic cooking and heating, power generation, industrial processes, and motor vehicles are the primary sources of air pollution in the developing country cities. Over the past twenty years, major advances have been made in understanding the social and economic consequences of air pollution. In both industrialized and developing countries, it has been shown that air pollution from energy combustion has detrimental impacts on human health and the environment. Lack of information on the sectoral contributions to air pollution - especially fine particulates, is one of the typical constraints for an effective integrated urban air quality management program. Without such information, it is difficult, if not impossible, for decision makers to provide policy advice and make informed investment decisions related to air quality improvements in developing countries. This also raises the need for low-cost ways of determining the principal sources of fine PM for a proper planning and decision making. The project objective is to develop and verify a methodology to assess and monitor the sources of PM, using a combination of ground-based monitoring and source apportionment techniques. This presentation will focus on four general tasks: (1) Review of the science and current activities in the combined use of monitoring data and modeling for better understanding of PM pollution. (2) Review of recent advances in atmospheric source apportionment techniques (e.g., principal component analysis, organic markers, source-receptor modeling techniques). (3) Develop a general methodology to use integrated top-down and bottom-up datasets. (4) Review of a series of current case studies from Africa, Asia and Latin America and the methodologies applied to assess the air pollution and its sources.

Source apportionment of speciated PM10 in the United Kingdom in 2008: Episodes and annual averages

NASA Astrophysics Data System (ADS)

Redington, A. L.; Witham, C. S.; Hort, M. C.

2016-11-01

The Lagrangian atmospheric dispersion model NAME (Numerical Atmospheric-dispersion Modelling Environment), has been used to simulate the formation and transport of PM10 over North-West Europe in 2008. The model has been evaluated against UK measurement data and been shown to adequately represent the observed PM10 at rural and urban sites on a daily basis. The Lagrangian nature of the model allows information on the origin of pollutants (and hence their secondary products) to be retained to allow attribution of pollutants at receptor sites back to their sources. This source apportionment technique has been employed to determine whether the different components of the modelled PM10 have originated from UK, shipping, European (excluding the UK) or background sources. For the first time this has been done to evaluate the composition during periods of elevated PM10 as well as the annual average composition. The episode data were determined by selecting the model data for each hour when the corresponding measurement data was >50 μg/m3. All the modelled sites show an increase in European pollution contribution and a decrease in the background contribution in the episode case compared to the annual average. The European contribution is greatest in southern and eastern parts of the UK and decreases moving northwards and westwards. Analysis of the speciated attribution data over the selected sites reveals that for 2008, as an annual average, the top three contributors to total PM10 are UK primary PM10 (17-25%), UK origin nitrate aerosol (18-21%) and background PM10 (11-16%). Under episode conditions the top three contributors to modelled PM10 are UK origin nitrate aerosol (12-33%), European origin nitrate aerosol (11-19%) and UK primary PM10 (12-18%).

Comparison of PM10 concentrations and metal content in three different sites of the Venice Lagoon: an analysis of possible aerosol sources.

PubMed

Contini, Daniele; Belosi, Franco; Gambaro, Andrea; Cesari, Daniela; Stortini, Angela Maria; Bove, Maria Chiara

2012-01-01

The Venice Lagoon is exposed to atmospheric pollutants from industrial activities, thermoelectric power plants, petrochemical plants, incinerator, domestic heating, ship traffic, glass factories and vehicular emissions on the mainland. In 2005, construction began on the mobile dams (MOSE), one dam for each channel connecting the lagoon to the Adriatic Sea as a barrier against high tide. These construction works could represent an additional source of pollutants. PM10 samples were taken on random days between 2007 and 2010 at three different sites: Punta Sabbioni, Chioggia and Malamocco, located near the respective dam construction worksites. Chemical analyses of V, Cr, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, Tl and Pb in PM10 samples were performed by Inductively coupled plasma-quadrupole mass spectrometry (ICP-QMS) and results were used to identify the main aerosol sources. The correlation of measured data with meteorology, and source apportionment, failed to highlight a contribution specifically associated to the emissions of the MOSE construction works. The comparison of the measurements at the three sites showed a substantial homogeneity of metal concentrations in the area. Source apportionment with principal component analysis (PCA) and positive matrix factorization (PMF) showed that a four principal factors model could describe the sources of metals in PM10. Three of them were assigned to specific sources in the area and one was characterised as a source of mixed origin (anthropogenic and crustal). A specific anthropogenic source of PM10 rich in Ni and Cr, active at the Chioggia site, was also identified.

Physically constrained source apportionment (PCSA) for polycyclic aromatic hydrocarbon using the Multilinear Engine 2-species ratios (ME2-SR) method.

PubMed

Liu, Gui-Rong; Shi, Guo-Liang; Tian, Ying-Ze; Wang, Yi-Nan; Zhang, Cai-Yan; Feng, Yin-Chang

2015-01-01

An improved physically constrained source apportionment (PCSA) technology using the Multilinear Engine 2-species ratios (ME2-SR) method was proposed and applied to quantify the sources of PM10- and PM2.5-associated polycyclic aromatic hydrocarbons (PAHs) from Chengdu in winter time. Sixteen priority PAH compounds were detected with mean ΣPAH concentrations (sum of 16 PAHs) ranging from 70.65 ng/m(3) to 209.58 ng/m(3) and from 59.17 ng/m(3) to 170.64 ng/m(3) for the PM10 and PM2.5 samples, respectively. The ME2-SR and positive matrix factorization (PMF) models were employed to estimate the source contributions of PAHs, and these estimates agreed with the experimental results. For the PMF model, the highest contributor to the ΣPAHs was vehicular emission (81.69% for PM10, 82.06% for PM2.5), followed by coal combustion (12.68%, 12.11%), wood combustion (5.65%, 4.45%) and oil combustion (0.72%, 0.88%). For the ME2-SR method, the highest contributions were from diesel (43.19% for PM10, 47.17% for PM2.5) and gasoline exhaust (34.94%, 32.44%), followed by wood combustion (8.79%, 6.37%), coal combustion (12.46%, 12.37%) and oil combustion (0.80%, 1.22%). However, the PAH ratios calculated for the factors extracted by ME2-SR were closer to the values from actual source profiles, implying that the results obtained from ME2-SR might be physically constrained and satisfactory. Copyright © 2014 Elsevier B.V. All rights reserved.

Composition and sources of fine particulate matter across urban and rural sites in the Midwestern United States

PubMed Central

Kundu, Shuvashish; Stone, Elizabeth. A.

2014-01-01

The composition and sources of fine particulate matter (PM2.5) were investigated in rural and urban locations in Iowa, located in the agricultural and industrial Midwestern United States from April 2009 to December 2012. Major chemical contributors to PM2.5 mass were sulfate, nitrate, ammonium, and organic carbon. Non-parametric statistical analyses demonstrated that the two rural sites had significantly enhanced levels of crustal materials (Si, Al) driven by agricultural activities and unpaved roads. Meanwhile, the three urban areas had enhanced levels of secondary aerosol (nitrate, sulfate, and ammonium) and combustion (organic and elemental carbon). The heavily industrialized Davenport site had significantly higher levels of PM2.5 and trace metals (Fe, Pb, Zn), demonstrating the important local impact of industrial point sources on air quality. Sources of PM2.5 were evaluated by the multi-variant positive matrix factorization (PMF) source apportionment model. For each individual site, seven to nine factors were identified: secondary sulfate (accounting for 29–30% of PM2.5), secondary nitrate (17–24%), biomass burning (9–21%), gasoline combustion (6–16), diesel combustion (3–9%), dust (6–11%), industry (0.4–5%) and winter salt (2–6%). Source contributions demonstrated a clear urban enhancement in PM2.5 from gasoline engines (by a factor of 1.14) and diesel engines (by a factor of 2.3), which is significant due to the well-documented negative health impacts of vehicular emissions. This study presents the first source apportionment results from the state of Iowa and is broadly applicable to understanding the differences in anthropogenic and natural sources in the urban-rural continuum of particle air pollution. PMID:24736797

Source apportionment of aerosol particles at a European air pollution hot spot using particle number size distributions and chemical composition.

PubMed

Leoni, Cecilia; Pokorná, Petra; Hovorka, Jan; Masiol, Mauro; Topinka, Jan; Zhao, Yongjing; Křůmal, Kamil; Cliff, Steven; Mikuška, Pavel; Hopke, Philip K

2018-03-01

Ostrava in the Moravian-Silesian region (Czech Republic) is a European air pollution hot spot for airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), and ultrafine particles (UFPs). Air pollution source apportionment is essential for implementation of successful abatement strategies. UFPs or nanoparticles of diameter <100 nm exhibit the highest deposition efficiency in human lungs. To permit apportionment of PM sources at the hot-spot including nanoparticles, Positive Matrix Factorization (PMF) was applied to highly time resolved particle number size distributions (NSD, 14 nm-10 μm) and PM 0.09-1.15 chemical composition. Diurnal patterns, meteorological variables, gaseous pollutants, organic markers, and associations between the NSD factors and chemical composition factors were used to identify the pollution sources. The PMF on the NSD reveals two factors in the ultrafine size range: industrial UFPs (28%, number mode diameter - NMD 45 nm), industrial/fresh road traffic nanoparticles (26%, NMD 26 nm); three factors in the accumulation size range: urban background (24%, NMD 93 nm), coal burning (14%, volume mode diameter - VMD 0.5 μm), regional pollution (3%, VMD 0.8 μm) and one factor in the coarse size range: industrial coarse particles/road dust (2%, VMD 5 μm). The PMF analysis of PM 0.09-1.15 revealed four factors: SIA/CC/BB (52%), road dust (18%), sinter/steel (16%), iron production (16%). The factors in the ultrafine size range resolved with NSD have a positive correlation with sinter/steel production and iron production factors resolved with chemical composition. Coal combustion factor resolved with NSD has moderate correlation with SIA/CC/BB factor. The organic markers homohopanes correlate with coal combustion and the levoglucosan correlates with urban background. The PMF applications to NSD and chemical composition datasets are complementary. PAHs in PM 1 were found to be associated with coal combustion factor. Copyright © 2017 Elsevier Ltd. All rights reserved.

PARTICLE SPECIATION AND EMISSION PROFILES OF SMALL 2-STROKE ENGINES

EPA Science Inventory

The Human Exposure and Atmospheric Sciences Division (HEASD) conducts studies designed to acquire information from emission sources for use in source apportionment studies. The objective of this work is to characterize a complete, speciated emission profile (PM and air toxics) ...

Source Apportionment of PM2.5 using PMF and CMB: Comparison of the Effects of Transboundary and Local Pollutions in the Western Japan

NASA Astrophysics Data System (ADS)

Iijima, A.; Sugata, S.

2014-12-01

PM2.5 has become one of the most important aspects in recent air pollution issues. In Japan, the achievement rate of the environmental quality standard for PM2.5 is in a worse situation so far (43.3% for ambient air monitoring station, 33.3% for roadside air pollution monitoring station in FY2012). Therefore, source apportionment will be essential to policy and decision making for improving the PM2.5 pollution. Since 2011, we started the field monitoring study called "Current Status Elucidation and Source Contribution Assessment of PM2.5 Pollution in Collaboration with Environmental Research Institutes across Japan" which was granted by the Environment Research and Technology Development Fund (5B-1101) of the Ministry of the Environment, Japan. PM2.5 samples were collected at 14 sites during four campaigns. Chemical analyses of carbonaceous compounds, ionic species, and elements were conducted. Source apportionment was performed by using Positive Matrix Factorization (PMF, EPA PMF 3.0) and Chemical Mass Balance (CMB, EPA CMB 8.1) models. PMF model resolved a six-factor solution. Each of these factors has a distinctive grouping of species that can be associated with a specific source sector (F1: Biomass burning, F2: Sulfate + Oil combustion, F3: Industry, F4: Nitrate, F5: Sulfate + Coal combustion, and F6: Chloride). In the winter campaign (Jan. 24 to Feb. 7) in 2013, F5 accounted for 50% of total PM2.5 mass at Tsushima (34.2°N 129.3°E, the westernmost remote site). The contribution of F5 tended to decrease toward the eastern sites (27% at Fukuoka (33.5°N 130.5°E, urban site), 22% at Higashi-Osaka (34.7°N 135.6°E, urban site)). CMB model showed similar results in the same campaign. Coal combustion accounted for 49%, 30%, and 22% of total PM2.5 mass at Tsushima, Fukuoka, and Higashi-Osaka, respectively (Fig.1). On the other hand, at urban sites, higher contributions from local sources such as secondary nitrate (16% at Fukuoka, 21% at Higashi-Osaka), diesel fuel automobile (11% at Fukuoka, 12% at Higashi-Osaka), and waste incineration (7% at Fukuoka, 14% at Higashi-Osaka) were observed. This study clearly shows that the effects from the local sources are also important at the urban sites in Japan, while the impact of transboundary pollution from the Asian Continent has attracted a lot of attention in recent years.

Source-sector contributions to European ozone and fine PM in 2010 using AQMEII modeling data

NASA Astrophysics Data System (ADS)

Karamchandani, Prakash; Long, Yoann; Pirovano, Guido; Balzarini, Alessandra; Yarwood, Greg

2017-05-01

Source apportionment modeling provides valuable information on the contributions of different source sectors and/or source regions to ozone (O3) or fine particulate matter (PM2.5) concentrations. This information can be useful in designing air quality management strategies and in understanding the potential benefits of reducing emissions from a particular source category. The Comprehensive Air quality Model with Extensions (CAMx) offers unique source attribution tools, called the Ozone and Particulate Source Apportionment Technology (OSAT/PSAT), which track source contributions. We present results from a CAMx source attribution modeling study for a summer month and a winter month using a recently evaluated European CAMx modeling database developed for Phase 3 of the Air Quality Model Evaluation International Initiative (AQMEII). The contributions of several source sectors (including model boundary conditions of chemical species representing transport of emissions from outside the modeling domain as well as initial conditions of these species) to O3 or PM2.5 concentrations in Europe were calculated using OSAT and PSAT, respectively. A 1-week spin-up period was used to reduce the influence of initial conditions. Evaluation focused on 16 major cities and on identifying source sectors that contributed above 5 %. Boundary conditions have a large impact on summer and winter ozone in Europe and on summer PM2.5, but they are only a minor contributor to winter PM2.5. Biogenic emissions are important for summer ozone and PM2.5. The important anthropogenic sectors for summer ozone are transportation (both on-road and non-road), energy production and conversion, and industry. In two of the 16 cities, solvent and product also contributed above 5 % to summertime ozone. For summertime PM2.5, the important anthropogenic source sectors are energy, transportation, industry, and agriculture. Residential wood combustion is an important anthropogenic sector in winter for PM2.5 over most of Europe, with larger contributions in central and eastern Europe and the Nordic cities. Other anthropogenic sectors with large contributions to wintertime PM2.5 include energy, transportation, and agriculture.

Monitoring and source apportionment of trace elements in PM2.5: Implications for local air quality management.

PubMed

Li, Yueyan; Chang, Miao; Ding, Shanshan; Wang, Shiwen; Ni, Dun; Hu, Hongtao

2017-07-01

Fine particulate matter (PM 2.5 ) samples were collected simultaneously every hour in Beijing between April 2014 and April 2015 at five sites. Thirteen trace elements (TEs) in PM 2.5 were analyzed by online X-ray fluorescence (XRF). The annual average PM 2.5 concentrations ranged from 76.8 to 102.7 μg m -3 . TEs accounted for 5.9%-8.7% of the total PM 2.5 mass with Cl, S, K, and Si as the most dominant elements. Spearman correlation coefficients of PM 2.5 or TE concentrations between the background site and other sites showed that PM 2.5 and some element loadings were affected by regional and local sources, whereas Cr, Si, and Ni were attributed to substantial local emissions. Temporal variations of TEs in PM 2.5 were significant and provided information on source profiles. The PM 2.5 concentrations were highest in autumn and lowest in summer. Mn and Cr showed similar variation. Fe, Ca, Si, and Ti tended to show higher concentrations in spring, whereas concentrations of S peaked in summer. Concentrations of Cl, K, Pb, Zn, Cu, and Ni peaked in winter. PM 2.5 and TE median concentrations were higher on Saturdays than on weekdays. The diurnal pattern of PM 2.5 and TE median concentrations yielded similar bimodal patterns. Five dominant sources of PM 2.5 mass were identified via positive matrix factorization (PMF). These sources included the regional and local secondary aerosols, traffic, coal burning, soil dust, and metal processing. Air quality management strategies, including regional environmental coordination and collaboration, reduction in secondary aerosol precursors, restrictive vehicle emission standards, promotion of public transport, and adoption of clean energy, should be strictly implemented. High time-resolution measurements of TEs provided detailed source profiles, which can greatly improve precision in interpreting source apportionment calculations; the PMF analysis of online XRF data is a powerful tool for local air quality management. Copyright © 2017 Elsevier Ltd. All rights reserved.

SOURCE APPORTIONMENT OF INDOOR, OUTDOOR, AND PERSONAL PM2.5 IN SEATTLE, WASHINGTON, USING POSITIVE MATRIX FACTORIZATION

EPA Science Inventory

As part of a large exposure assessment and health effects panel study, 33 trace elements and light-absorbing carbon were measured on 24-hr particulate matter with an aero-dynamic diameter <2.5 um (PM2.5) fixed-site filter samples collected between September 26, 2000, and May 25, ...

RADIOCARBON SOURCE APPORTIONMENT IN A BIOFUELS ERA

EPA Science Inventory

Biofuels (gasohol and biodiesel) introduce radiocarbon into the U.S. mobile source fuel supply where it was previously absent. Initial measurements of radiocarbon in the PM_2.5 combustion emissions from engines using gasohol indicate that this may have less effect on r...

Characterizing and sourcing ambient PM2.5 over key emission regions in China II: Organic molecular markers and CMB modeling

NASA Astrophysics Data System (ADS)

Zhou, Jiabin; Xiong, Ying; Xing, Zhenyu; Deng, Junjun; Du, Ke

2017-08-01

From November 2012 to July 2013, a sampling campaign was completed for comprehensive characterization of PM2.5 over four key emission regions in China: Beijing-Tianjin-Hebei (BTH), Yangzi River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB). A multi-method approach, adopting different analytical and receptor modeling methods, was employed to determine the relative abundances of region-specific air pollution constituents and contributions of emission sources. This paper is focused on organic molecular marker based source apportionment using chemical mass balance (CMB) receptor modeling. Analyses of the organic molecular markers revealed that vehicle emission, coal combustion, biomass burning, meat cooking and natural gas combustion were the major contributors to organic carbon (OC) in PM2.5. The vehicle emission dominated the sources contributing to OC in spring at four sampling sites. During wintertime, the coal combustion had highest contribution to OC at BTH site, while the major source contributing to OC at YRD and PRD sites was vehicle emission. In addition, the relative contributions of different emission sources to PM2.5 mass at a specific location site and in a specific season revealed seasonal and spatial variations across all four sampling locations. The largest contributor to PM2.5 mass was secondary sulfate (14-17%) in winter at the four sites. The vehicle emission was found to be the major source (14-21%) for PM2.5 mass at PRD site. The secondary ammonium has minor variation (4-5%) across the sites, confirming the influences of regional emission sources on these sites. The distinct patterns of seasonal and spatial variations of source apportionment observed in this study were consistent with the findings in our previous paper based upon water-soluble ions and carbonaceous fractions. This makes it essential for the local government to make season- and region-specific mitigation strategies for abating PM2.5 pollution in China.

Contribution of regional-scale fire events to ozone and PM2.5 ...

EPA Pesticide Factsheets

Two specific fires from 2011 are tracked for local to regional scale contribution to ozone (O3) and fine particulate matter (PM2.5) using a freely available regulatory modeling system that includes the BlueSky wildland fire emissions tool, Spare Matrix Operator Kernel Emissions (SMOKE) model, Weather and Research Forecasting (WRF) meteorological model, and Community Multiscale Air Quality (CMAQ) photochemical grid model. The modeling system was applied to track the contribution from a wildfire (Wallow) and prescribed fire (Flint Hills) using both source sensitivity and source apportionment approaches. The model estimated fire contribution to primary and secondary pollutants are comparable using source sensitivity (brute-force zero out) and source apportionment (Integrated Source Apportionment Method) approaches. Model estimated O3 enhancement relative to CO is similar to values reported in literature indicating the modeling system captures the range of O3 inhibition possible near fires and O3 production both near the fire and downwind. O3 and peroxyacetyl nitrate (PAN) are formed in the fire plume and transported downwind along with highly reactive VOC species such as formaldehyde and acetaldehyde that are both emitted by the fire and rapidly produced in the fire plume by VOC oxidation reactions. PAN and aldehydes contribute to continued downwind O3 production. The transport and thermal decomposition of PAN to nitrogen oxides (NOX) enables O3 production in areas

Atmospheric aerosol composition and source apportionments to aerosol in southern Taiwan

NASA Astrophysics Data System (ADS)

Tsai, Ying I.; Chen, Chien-Lung

In this study, the chemical characteristics of winter aerosol at four sites in southern Taiwan were determined and the Gaussian Trajectory transfer coefficient model (GTx) was then used to identify the major air pollutant sources affecting the study sites. Aerosols were found to be acidic at all four sites. The most important constituents of the particulate matter (PM) by mass were SO 42-, organic carbon (OC), NO 3-, elemental carbon (EC) and NH 4+, with SO 42-, NO 3-, and NH 4+ together constituting 86.0-87.9% of the total PM 2.5 soluble inorganic salts and 68.9-78.3% of the total PM 2.5-10 soluble inorganic salts, showing that secondary photochemical solution components such as these were the major contributors to the aerosol water-soluble ions. The coastal site, Linyuan (LY), had the highest PM mass percentage of sea salts, higher in the coarse fraction, and higher sea salts during daytime than during nighttime, indicating that the prevailing daytime sea breeze brought with it more sea-salt aerosol. Other than sea salts, crustal matter, and EC in PM 2.5 at Jenwu (JW) and in PM 2.5-10 at LY, all aerosol components were higher during nighttime, due to relatively low nighttime mixing heights limiting vertical and horizontal dispersion. At JW, a site with heavy traffic loadings, the OC/EC ratio in the nighttime fine and coarse fractions of approximately 2.2 was higher than during daytime, indicating that in addition to primary organic aerosol (POA), secondary organic aerosol (SOA) also contributed to the nighttime PM 2.5. This was also true of the nighttime coarse fraction at LY. The GTx produced correlation coefficients ( r) for simulated and observed daily concentrations of PM 10 at the four sites (receptors) in the range 0.45-0.59 and biases from -6% to -20%. Source apportionment indicated that point sources were the largest PM 10 source at JW, LY and Daliao (DL), while at Meinung (MN), a suburban site with less local PM 10, SO x and NO x emissions, upwind boundary concentration was the major PM 10 source, followed by point sources and top boundary concentration.

PARTICULATE ORGANIC SOURCE MARKERS IN THE NEW YORK CITY METROPOLITAN AREA

EPA Science Inventory

A sampling network of four sites was established for the Speciation of Organics for Apportionment of PM2.5 (SOAP) project during 2002-2003 to investigate composition, seasonal and spatial variability, and source contributions to particulate organic matter in the New York City met...

Identifying the Sources Contributing to PM Exceedances in Ostrava, Czech Republic, Using Passive Aerosol Sampling Coupled with Computer-Controlled Microscopy

EPA Science Inventory

The Czech Hydrometeorological Institute (CHMI) in collaboration with the U.S. Environmental Protection Agency conducted a multi-pollutant source apportionment study in 2012 to quantify the impact of regional as well as local sources on air quality in the Ostrava metropolitan area...

Source Contributions to Wintertime Elemental and Organic Carbon in the Western Arctic Based on Radiocarbon and Tracer Apportionment.

PubMed

Barrett, T E; Robinson, E M; Usenko, S; Sheesley, R J

2015-10-06

To quantify the contributions of fossil and biomass sources to the wintertime Arctic aerosol burden source apportionment is reported for elemental (EC) and organic carbon (OC) fractions of six PM10 samples collected during a wintertime (2012-2013) campaign in Barrow, AK. Radiocarbon apportionment of EC indicates that fossil sources contribute an average of 68 ± 9% (0.01-0.07 μg m(-3)) in midwinter decreasing to 49 ± 6% (0.02 μg m(-3)) in late winter. The mean contribution of fossil sources to OC for the campaign was stable at 38 ± 8% (0.04-0.32 μg m(-3)). Samples were also analyzed for organic tracers, including levoglucosan, for use in a chemical mass balance (CMB) source apportionment model. The CMB model was able to apportion 24-53% and 99% of the OC and EC burdens, respectively, during the campaign, with fossil OC contributions ranging from 25 to 74% (0.02-0.09 μg m(-3)) and fossil EC contributions ranging from 73 to 94% (0.03-0.07 μg m(-3)). Back trajectories identified two major wintertime source regions to Barrow: the Russian and North American Arctic. Atmospheric lifetimes of levoglucosan, ranging from 50 to 320 h, revealed variability in wintertime atmospheric processing of this biomass burning tracer. This study allows for unambiguous apportionment of EC to fossil fuel and biomass combustion sources and intercomparison with CMB modeling.

Advanced receptor modelling for the apportionment of road dust resuspension to atmospheric PM

NASA Astrophysics Data System (ADS)

Amato, F.; Pandolfi, M.; Escrig, A.; Querol, X.; Alastuey, A.; Pey, J.; Perez, N.; Hopke, P. K.

2009-04-01

Fugitive emissions from traffic resuspension can often represent an important source of atmospheric particulate matter in urban environments, especially when the scarce precipitations favour the accumulation of road dust. Resuspension of road dust can lead to high exposures to heavy metals, metalloids and mineral matter. Knowing the amount of its contribution to atmospheric PM is a key task for establishing eventual mitigation or preventive measures. Factor analysis techniques are widely used tools for atmospheric aerosol source apportionment, based on the mass conservation principle. Paatero and Tapper (1993) suggested the use of a Weighted Least Squares scheme with the aim of obtaining a minimum variance solution. Additionally they proposed to incorporate the basic physical constraint of non negativity, calling their approach Positive Matrix Factorization (PMF), which can be performed by the program PMF2 released by Paatero (1997). Nevertheless, Positive Matrix Factorization can be either solved with the Multilinear Engine (ME-2), a more flexible program, also developed by Paatero (1999), which can solve any model consisting in sum of products of unknowns. The main difference with PMF2 is that ME-2 does not solve only well-defined tasks, but its actions are defined in a "script file" written in a special-purpose programming language, allowing incorporating additional tasks such as data processing etc. Thus in ME-2 a priori information, e.g. chemical fingerprints can be included as auxiliary terms of the object function to be minimized. This feature of ME-2 make it especially suitable for source apportionment studies where some knowledge (chemical ratios, profiles, mass conservation etc) of involved sources is available. The aim of this study was to quantify the contribution of road dust resuspension in PM10, PM2.5 and PM1 data set from Barcelona (Spain). Given that recently the emission profile of local road dust was characterized (Amato et al., in press), authors show how to apply in ME-2 this knowledge to obtain a quantitative assessment of this source. The achievement of this objective permitted to show how is possible to improve a basic solution of PMF2 basing on an extended model. Results show that road dust resuspension accounted for 6.7 µg/m3 (16%) in PM10, 2.2 µg/m3 (8%) of PM2.5 and 0.3 µg/m3 (1%) of PM1, revealing that fugitive emissions were responsible of the 36%, 18% and 2% of total traffic emissions respectively in PM10, PM2.5 and PM1. Acknowledments: This work was funded by the Spanish Ministry of Science and Innovation (GRACCIE-SCD2007-00067)

The Denver Aerosol Sources and Health (DASH) Study: Overview and Early Findings

PubMed Central

Vedal, S.; Hannigan, M.P.; Dutton, S.J.; Miller, S. L.; Milford, J.B.; Rabinovitch, N.; Kim, S.-Y.; Sheppard, L.

2012-01-01

Improved understanding of the sources of air pollution that are most harmful could aid in developing more effective measures for protecting human health. The Denver Aerosol Sources and Health (DASH) study was designed to identify the sources of ambient fine particulate matter (PM2.5) that are most responsible for the adverse health effects of short-term exposure to PM 2.5. Daily 24-hour PM2.5 sampling began in July 2002 at a residential monitoring site in Denver, Colorado, using both Teflon and quartz filter samplers. Sampling is planned to continue through 2008. Chemical speciation is being carried out for mass, inorganic ionic compounds (sulfate, nitrate and ammonium), and carbonaceous components, including elemental carbon, organic carbon, temperature-resolved organic carbon fractions and a large array of organic compounds. In addition, water soluble metals were measured daily for 12 months in 2003. A receptor-based source apportionment approach utilizing positive matrix factorization (PMF) will be used to identify PM 2.5 source contributions for each 24-hour period. Based on a preliminary assessment using synthetic data, the proposed source apportionment should be able to identify many important sources on a daily basis, including secondary ammonium nitrate and ammonium sulfate, diesel vehicle exhaust, road dust, wood combustion and vegetative debris. Meat cooking, gasoline vehicle exhaust and natural gas combustion were more challenging for PMF to accurately identify due to high detection limits for certain organic molecular marker compounds. Measurements of these compounds are being improved and supplemented with additional organic molecular marker compounds. The health study will investigate associations between daily source contributions and an array of health endpoints, including daily mortality and hospitalizations and measures of asthma control in asthmatic children. Findings from the DASH study, in addition to being of interest to policymakers, by identifying harmful PM2.5 sources may provide insights into mechanisms of PM effect. PMID:22723735

The Denver Aerosol Sources and Health (DASH) study: Overview and early findings

NASA Astrophysics Data System (ADS)

Vedal, S.; Hannigan, M. P.; Dutton, S. J.; Miller, S. L.; Milford, J. B.; Rabinovitch, N.; Kim, S.-Y.; Sheppard, L.

Improved understanding of the sources of air pollution that are most harmful could aid in developing more effective measures for protecting human health. The Denver Aerosol Sources and Health (DASH) study was designed to identify the sources of ambient fine particulate matter (PM 2.5) that are most responsible for the adverse health effects of short-term exposure to PM 2.5. Daily 24-h PM 2.5 sampling began in July 2002 at a residential monitoring site in Denver, Colorado, using both Teflon and quartz filter samplers. Sampling is planned to continue through 2008. Chemical speciation is being carried out for mass, inorganic ionic compounds (sulfate, nitrate and ammonium), and carbonaceous components, including elemental carbon, organic carbon, temperature-resolved organic carbon fractions and a large array of organic compounds. In addition, water-soluble metals were measured daily for 12 months in 2003. A receptor-based source apportionment approach utilizing positive matrix factorization (PMF) will be used to identify PM 2.5 source contributions for each 24-h period. Based on a preliminary assessment using synthetic data, the proposed source apportionment should be able to identify many important sources on a daily basis, including secondary ammonium nitrate and ammonium sulfate, diesel vehicle exhaust, road dust, wood combustion and vegetative debris. Meat cooking, gasoline vehicle exhaust and natural gas combustion were more challenging for PMF to accurately identify due to high detection limits for certain organic molecular marker compounds. Measurements of these compounds are being improved and supplemented with additional organic molecular marker compounds. The health study will investigate associations between daily source contributions and an array of health endpoints, including daily mortality and hospitalizations and measures of asthma control in asthmatic children. Findings from the DASH study, in addition to being of interest to policymakers, by identifying harmful PM 2.5 sources may provide insights into mechanisms of PM effect.

Chemical composition and source apportionment of PM10 at an urban background site in a high-altitude Latin American megacity (Bogota, Colombia).

PubMed

Ramírez, Omar; Sánchez de la Campa, A M; Amato, Fulvio; Catacolí, Ruth A; Rojas, Néstor Y; de la Rosa, Jesús

2018-02-01

Bogota registers frequent episodes of poor air quality from high PM 10 concentrations. It is one of the main Latin American megacities, located at 2600 m in the tropical Andes, but there is insufficient data on PM 10 source contribution. A characterization of the chemical composition and the source apportionment of PM 10 at an urban background site in Bogota was carried out in this study. Daily samples were collected from June 2015 to May 2016 (a total of 311 samples). Organic carbon (OC), elemental carbon (EC), water soluble compounds (SO 4 2- , Cl - , NO 3 - , NH 4 + ), major elements (Al, Fe, Mg, Ca, Na, K, P) and trace metals (V, Cd, Pb, Sr, Ba, among others) were analyzed. The results were interpreted in terms of their variability during the rainy season (RS) and the dry season (DS). The data obtained revealed that the carbonaceous fraction (∼51%) and mineral dust (23%) were the main PM 10 components, followed by others (15%), Secondary Inorganic Compounds (SIC) (11%) and sea salt (0.4%). The average concentrations of soil, SIC and OC were higher during RS than DS. However, peak values were observed during the DS due to photochemical activity and forest fires. Although trace metals represented <1% of PM 10 , high concentrations of toxic elements such as Pb and Sb on RS, and Cu on DS, were obtained. By using a PMF model, six factors were identified (∼96% PM 10 ) including fugitive dust, road dust, metal processing, secondary PM, vehicles exhaust and industrial emissions. Traffic (exhaust emissions + road dust) was the major PM 10 source, accounting for ∼50% of the PM 10 . The results provided novel data about PM 10 chemical composition, its sources and its seasonal variability during the year, which can help the local government to define control strategies for the main emission sources during the most critical periods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Source Apportionment of the Summer Time Carbonaceous Aerosol at Nordic Rural Background Sites

EPA Science Inventory

In the present study, natural and anthropogenic sources of particulate organic carbon (OC_p) and elemental carbon (EC) have been quantified based on weekly filter samples of PM₁₀ (particles with aerodynamic diameter <10µ collected at four Nordic rural backgro...

Assessment of light extinction at a European polluted urban area during wintertime: Impact of PM1 composition and sources.

PubMed

Vecchi, R; Bernardoni, V; Valentini, S; Piazzalunga, A; Fermo, P; Valli, G

2018-02-01

In this paper, results from receptor modelling performed on a well-characterised PM 1 dataset were combined to chemical light extinction data (b ext ) with the aim of assessing the impact of different PM 1 components and sources on light extinction and visibility at a European polluted urban area. It is noteworthy that, at the state of the art, there are still very few papers estimating the impact of different emission sources on light extinction as we present here, although being among the major environmental challenges at many polluted areas. Following the concept of the well-known IMPROVE algorithm, here a tailored site-specific approach (recently developed by our group) was applied to assess chemical light extinction due to PM 1 components and major sources. PM 1 samples collected separately during daytime and nighttime at the urban area of Milan (Italy) were chemically characterised for elements, major ions, elemental and organic carbon, and levoglucosan. Chemical light extinction was estimated and results showed that at the investigated urban site it is heavily impacted by ammonium nitrate and organic matter. Receptor modelling (i.e. Positive Matrix Factorization, EPA-PMF 5.0) was effective to obtain source apportionment; the most reliable solution was found with 7 factors which were tentatively assigned to nitrates, sulphates, wood burning, traffic, industry, fine dust, and a Pb-rich source. The apportionment of aerosol light extinction (b ext,aer ) according to resolved sources showed that considering all samples together nitrate contributed at most (on average 41.6%), followed by sulphate, traffic, and wood burning accounting for 18.3%, 17.8% and 12.4%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemical Characterization and Source Apportionment of Indoor and Outdoor Fine Particulate Matter (PM2.5) in Retirement Communities of the Los Angeles Basin

PubMed Central

Hasheminassab, Sina; Daher, Nancy; Shafer, Martin M.; Schauer, James J.; Delfino, Ralph J.; Sioutas, Constantinos

2014-01-01

Concurrent indoor and outdoor measurements of fine particulate matter (PM2.5) were conducted at three retirement homes in the Los Angeles Basin during two separate phases (cold and warm) between 2005 and 2006. Indoor-to-outdoor relationships of PM2.5 chemical constituents were determined and sources of indoor and outdoor PM2.5 were evaluated using a molecular marker-based chemical mass balance (MM-CMB) model. Indoor levels of elemental carbon (EC) along with metals and trace elements were found to be significantly affected by outdoor sources. EC, in particular, displayed very high indoor-to-outdoor (I/O) mass ratios accompanied by strong I/O correlations, illustrating the significant impact of outdoor sources on indoor levels of EC. Similarly, indoor levels of polycyclic aromatic hydrocarbons (PAHs), hopanes, and steranes were strongly correlated with their outdoor components and displayed I/O ratios close to unity. On the other hand, concentrations of n-alkanes and organic acids inside the retirement communities were dominated by indoor sources (e.g. food cooking and consumer products), as indicated by their I/O ratios, which exceeded unity. Source apportionment results revealed that vehicular emissions were the major contributor to both indoor and outdoor PM2.5, accounting for 39 and 46% of total mass, respectively. Moreover, the contribution of vehicular sources to indoor levels was generally comparable to its corresponding outdoor estimate. Other water-insoluble organic matter (other WIOM), which accounts for emissions from uncharacterized primary biogenic sources, displayed a wider range of contributions, varying from 2 to 73% of PM2.5, across all sites and phases of the study. Lastly, higher indoor than outdoor contribution of other water-soluble organic matter (other WSOM) was evident at some of the sites, suggesting the production of secondary aerosols as well as direct emissions from primary sources (including cleaning or other consumer products) at the indoor environments. PMID:24880542

A systematic analysis of PM2.5 in Beijing and its sources from 2000 to 2012

NASA Astrophysics Data System (ADS)

Lv, Baolei; Zhang, Bin; Bai, Yuqi

2016-01-01

Particulate matter with an aerodynamic diameter of 2.5 μm or less (PM2.5) is the main air pollutant in Beijing. To have a comprehensive understanding of concentrations, compositions and sources of PM2.5 in Beijing, recent studies reporting ground-based observations and source apportionment results dated from 2000 to 2012 in this typical large city of China are reviewed. Statistical methods were also used to better enable data comparison. During the last decade, annual average concentrations of PM2.5 have decreased and seasonal mean concentrations declined through autumn and winter. Generally, winter is the most polluted season and summer is the least polluted one. Seasonal variance of PM2.5 levels decreased. For diurnal variance, PM2.5 generally increases at night and decreases during the day. On average, organic matters, sulfate, nitrate and ammonium are the major compositions of PM2.5 in Beijing. Fractions of organic matters increased from 2000 to 2004, and decreased afterwards. Fractions of sulfate, nitrate and ammonium decreased in winter and remained largely unchanged in summer. Concentrations of organic carbon and elemental carbon were always higher in winter than in summer and they barely changed during the last decade. Concentrations of sulfate, nitrate and ammonium exhibited significant increasing trend in summer but in reverse in winter. On average they were higher in winter than in summer before 2005, and took a reverse after 2005. Receptor model results show that vehicle, dust, industry, biomass burning, coal combustion and secondary products were major sources and they all increased except coal combustions and secondary products. The growth was decided both changing social and economic activities in Beijing, and most likely growing emissions in neighboring Hebei province. Explicit descriptions of the spatial variations of PM2.5 concentration, better methods to estimate secondary products and ensemble source apportionments models to reduce uncertainties would remain being open questions for future studies.

Reconciling PM10 analyses by different sampling methods for Iron King Mine tailings dust.

PubMed

Li, Xu; Félix, Omar I; Gonzales, Patricia; Sáez, Avelino Eduardo; Ela, Wendell P

2016-03-01

The overall project objective at the Iron King Mine Superfund site is to determine the level and potential risk associated with heavy metal exposure of the proximate population emanating from the site's tailings pile. To provide sufficient size-fractioned dust for multi-discipline research studies, a dust generator was built and is now being used to generate size-fractioned dust samples for toxicity investigations using in vitro cell culture and animal exposure experiments as well as studies on geochemical characterization and bioassay solubilization with simulated lung and gastric fluid extractants. The objective of this study is to provide a robust method for source identification by comparing the tailing sample produced by dust generator and that collected by MOUDI sampler. As and Pb concentrations of the PM10 fraction in the MOUDI sample were much lower than in tailing samples produced by the dust generator, indicating a dilution of Iron King tailing dust by dust from other sources. For source apportionment purposes, single element concentration method was used based on the assumption that the PM10 fraction comes from a background source plus the Iron King tailing source. The method's conclusion that nearly all arsenic and lead in the PM10 dust fraction originated from the tailings substantiates our previous Pb and Sr isotope study conclusion. As and Pb showed a similar mass fraction from Iron King for all sites suggesting that As and Pb have the same major emission source. Further validation of this simple source apportionment method is needed based on other elements and sites.

Quantification of source impact to PM using three-dimensional weighted factor model analysis on multi-site data

NASA Astrophysics Data System (ADS)

Shi, Guoliang; Peng, Xing; Huangfu, Yanqi; Wang, Wei; Xu, Jiao; Tian, Yingze; Feng, Yinchang; Ivey, Cesunica E.; Russell, Armistead G.

2017-07-01

Source apportionment technologies are used to understand the impacts of important sources of particulate matter (PM) air quality, and are widely used for both scientific studies and air quality management. Generally, receptor models apportion speciated PM data from a single sampling site. With the development of large scale monitoring networks, PM speciation are observed at multiple sites in an urban area. For these situations, the models should account for three factors, or dimensions, of the PM, including the chemical species concentrations, sampling periods and sampling site information, suggesting the potential power of a three-dimensional source apportionment approach. However, the principle of three-dimensional Parallel Factor Analysis (Ordinary PARAFAC) model does not always work well in real environmental situations for multi-site receptor datasets. In this work, a new three-way receptor model, called "multi-site three way factor analysis" model is proposed to deal with the multi-site receptor datasets. Synthetic datasets were developed and introduced into the new model to test its performance. Average absolute error (AAE, between estimated and true contributions) for extracted sources were all less than 50%. Additionally, three-dimensional ambient datasets from a Chinese mega-city, Chengdu, were analyzed using this new model to assess the application. Four factors are extracted by the multi-site WFA3 model: secondary source have the highest contributions (64.73 and 56.24 μg/m3), followed by vehicular exhaust (30.13 and 33.60 μg/m3), crustal dust (26.12 and 29.99 μg/m3) and coal combustion (10.73 and 14.83 μg/m3). The model was also compared to PMF, with general agreement, though PMF suggested a lower crustal contribution.

Ambient PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) in Changhua County, central Taiwan: Seasonal variation, source apportionment and cancer risk assessment.

PubMed

Chen, Yu-Cheng; Chiang, Hung-Che; Hsu, Chin-Yu; Yang, Tzu-Ting; Lin, Tzu-Yu; Chen, Mu-Jean; Chen, Nai-Tzu; Wu, Yuh-Shen

2016-11-01

This study investigates PM 2.5 -bound PAHs for rural sites (Dacheng and Fangyuan) positioned close to heavy air-polluting industries in Changhua County, central Taiwan. A total of 113 PM 2.5 samples with 22 PAHs collected from 2014 to 2015 were analyzed, and Positive Matrix Factorization (PMF) and diagnostic ratios of PAHs were applied to quantify potential PAH sources. The influences of local and regional sources were also explored using the conditional probability function (CPF) and potential source contribution function (PSCF) with PMF-modeled results, respectively. Annual mean concentrations of total PAHs were 2.91 ± 1.34 and 3.04 ± 1.40 ng/m 3 for Dacheng and Fangyuan, respectively, and their corresponding BaP eq were measured at 0.534 ± 0.255 and 0.563 ± 0.273 ng/m 3 in concentration. Seasonal variations with higher PAHs found for the winter than for the spring and summer were observed for both sites. The lifetime excess cancer risk (ECR) from inhalation exposure to PAHs was recorded as 4.7 × 10 -5 overall. Potential sources of PM 2.5 -bound PAHs include unburned petroleum and traffic emissions (42%), steel industry and coal combustion (31%), and petroleum and oil burning (27%), and unburned petroleum and traffic emission could contribute the highest ECR (2.4 × 10 -5 ). The CPF results show that directional apportionment patterns were consistent with the actual locations of local PAH sources. The PSCF results indicate that mainly northeastern regions of China have contributed elevated PM 2.5 -bound PAHs from long-range transports. Copyright © 2016 Elsevier Ltd. All rights reserved.

Primary sources of PM2.5 organic aerosol in an industrial Mediterranean city, Marseille

NASA Astrophysics Data System (ADS)

El Haddad, I.; Marchand, N.; Wortham, H.; Piot, C.; Besombes, J.-L.; Cozic, J.; Chauvel, C.; Armengaud, A.; Robin, D.; Jaffrezo, J.-L.

2011-03-01

Marseille, the most important port of the Mediterranean Sea, represents a challenging case study for source apportionment exercises, combining an active photochemistry and multiple emission sources, including fugitive emissions from industrial sources and shipping. This paper presents a Chemical Mass Balance (CMB) approach based on organic markers and metals to apportion the primary sources of organic aerosol in Marseille, with a special focus on industrial emissions. Overall, the CMB model accounts for the major primary anthropogenic sources including motor vehicles, biomass burning and the aggregate emissions from three industrial processes (heavy fuel oil combustion/shipping, coke production and steel manufacturing) as well as some primary biogenic emissions. This source apportionment exercise is well corroborated by 14C measurements. Primary OC estimated by the CMB accounts on average for 22% of total OC and is dominated by the vehicular emissions that contribute on average for 17% of OC mass concentration (vehicular PM contributes for 17% of PM2.5). Even though industrial emissions contribute only 2.3% of the total OC (7% of PM2.5), they are associated with ultrafine particles (Dp<80 nm) and high concentrations of Polycyclic Aromatic Hydrocarbons (PAH) and heavy metals such as Pb, Ni and V. On one hand, given that industrial emissions governed key primary markers, their omission would lead to substantial uncertainties in the CMB analysis performed in areas heavily impacted by such sources, hindering accurate estimation of non-industrial primary sources and secondary sources. On the other hand, being associated with bursts of submicron particles and carcinogenic and mutagenic components such as PAH, these emissions are most likely related with acute ill-health outcomes and should be regulated despite their small contributions to OC. Another important result is the fact that 78% of OC mass cannot be attributed to the major primary sources and, thus, remains un-apportioned. We have consequently critically investigated the uncertainties underlying our CMB apportionments. While we have provided some evidence for photochemical decay of hopanes, this decay does not appear to significantly alter the CMB estimates of the total primary OC. Sampling artifacts and unaccounted primary sources also appear to marginally influence the amount of un-apportioned OC. Therefore, this significant amount of un-apportioned OC is mostly attributed to secondary organic carbon that appears to be the major component of OC during the whole period of study.

Two Model-Based Methods for Policy Analyses of Fine Particulate Matter Control in China: Source Apportionment and Source Sensitivity

NASA Astrophysics Data System (ADS)

Li, X.; Zhang, Y.; Zheng, B.; Zhang, Q.; He, K.

2013-12-01

Anthropogenic emissions have been controlled in recent years in China to mitigate fine particulate matter (PM2.5) pollution. Recent studies show that sulfate dioxide (SO2)-only control cannot reduce total PM2.5 levels efficiently. Other species such as nitrogen oxide, ammonia, black carbon, and organic carbon may be equally important during particular seasons. Furthermore, each species is emitted from several anthropogenic sectors (e.g., industry, power plant, transportation, residential and agriculture). On the other hand, contribution of one emission sector to PM2.5 represents contributions of all species in this sector. In this work, two model-based methods are used to identify the most influential emission sectors and areas to PM2.5. The first method is the source apportionment (SA) based on the Particulate Source Apportionment Technology (PSAT) available in the Comprehensive Air Quality Model with extensions (CAMx) driven by meteorological predictions of the Weather Research and Forecast (WRF) model. The second method is the source sensitivity (SS) based on an adjoint integration technique (AIT) available in the GEOS-Chem model. The SA method attributes simulated PM2.5 concentrations to each emission group, while the SS method calculates their sensitivity to each emission group, accounting for the non-linear relationship between PM2.5 and its precursors. Despite their differences, the complementary nature of the two methods enables a complete analysis of source-receptor relationships to support emission control policies. Our objectives are to quantify the contributions of each emission group/area to PM2.5 in the receptor areas and to intercompare results from the two methods to gain a comprehensive understanding of the role of emission sources in PM2.5 formation. The results will be compared in terms of the magnitudes and rankings of SS or SA of emitted species and emission groups/areas. GEOS-Chem with AIT is applied over East Asia at a horizontal grid resolution of 0.5° (Lat) × 0.67° (Lon). WRF/CAMx with PSAT is applied to nested grids: 36-km × 36-km over China and 12-km × 12-km over northern China. These simulations are performed for 2006 and 2011. Beijing and northern Hebei are selected as representative receptor areas. Simulated surface concentrations by both models are evaluated with available observations in China. Focusing on inorganic aerosols (sulfate, nitrate and ammonium), preliminary SS results from GEOS-Chem/AIT at Beijing identify the top three major emission sectors to be agriculture, residential, and transportation in winter and agriculture, industry and power plant in summer. The top four source areas are northern Hebei, local, Neimenggu, and Liaoning in winter and northern Hebei, local, Shandong, and southern Hebei in summer. The synthesis of SS and SA for influential emission groups or areas from this work will provide a quantitative basis for emission control strategy development and policy making for PM2.5 control in China.

Fine particulate matter (PM2.5) in Edmonton, Canada: Source apportionment and potential risk for human health.

PubMed

Bari, Md Aynul; Kindzierski, Warren B

2016-11-01

To design effective PM 2.5 control strategies in urban centers, there is a need to better understand local and remote sources influencing PM 2.5 levels and associated risk to public health. An investigation of PM 2.5 levels, sources and potential human health risk associated with trace elements in the PM 2.5 was undertaken in Edmonton over a 6-year period (September 2009-August 2015). The geometric mean PM 2.5 concentration of was 7.11 μg/m 3 (interquartile range, IQR = 4.83-10.08 μg/m 3 ). Positive matrix factorization (PMF) receptor modeling identified secondary organic aerosol (SOA) as the major contributor (2.2 μg/m 3 , 27%), followed by secondary nitrate (1.3 μg/m 3 , 17%) and secondary sulfate (1.2 μg/m 3 , 15%). Other local sources included transportation (1.1 μg/m 3 , 14%) and industry-related emissions (0.26 μg/m 3 , 3.4%), biomass burning (1.0 μg/m 3 , 13%) and soil (0.54 μg/m 3 , 6.8%). Five factors (i.e., SOA, secondary nitrate, secondary sulfate, transportation and biomass burning) contributed more than 85% to PM 2.5 for the 2009-2015 period. Geometric (arithmetic) mean and maximum ambient air concentrations for hazardous trace elements of public health concern in PM 2.5 during the study period were below United States regulatory agency chronic and acute health risk screening criteria. Carcinogenic and non-carcinogenic risk of trace elements and source-specific risk values were well below acceptable and safe levels of risks recommended by regulatory agencies. More work is needed to understand the origin of potential SOA and wintertime wood burning sources in Edmonton and the surrounding region and to apply source-risk apportionment using all available hazardous air pollutants (HAPs) including organic compounds to better interpret the potential health risk posed by various sources in urban areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quantifying road dust resuspension in urban environment by Multilinear Engine: A comparison with PMF2

NASA Astrophysics Data System (ADS)

Amato, F.; Pandolfi, M.; Escrig, A.; Querol, X.; Alastuey, A.; Pey, J.; Perez, N.; Hopke, P. K.

Atmospheric PM pollution from traffic comprises not only direct emissions but also non-exhaust emissions because resuspension of road dust that can produce high human exposure to heavy metals, metalloids, and mineral matter. A key task for establishing mitigation or preventive measures is estimating the contribution of road dust resuspension to the atmospheric PM mixture. Several source apportionment studies, applying receptor modeling at urban background sites, have shown the difficulty in identifying a road dust source separately from other mineral sources or vehicular exhausts. The Multilinear Engine (ME-2) is a computer program that can solve the Positive Matrix Factorization (PMF) problem. ME-2 uses a programming language permitting the solution to be guided toward some possible targets that can be derived from a priori knowledge of sources (chemical profile, ratios, etc.). This feature makes it especially suitable for source apportionment studies where partial knowledge of the sources is available. In the present study ME-2 was applied to data from an urban background site of Barcelona (Spain) to quantify the contribution of road dust resuspension to PM 10 and PM 2.5 concentrations. Given that recently the emission profile of local resuspended road dust was obtained (Amato, F., Pandolfi, M., Viana, M., Querol, X., Alastuey, A., Moreno, T., 2009. Spatial and chemical patterns of PM 10 in road dust deposited in urban environment. Atmospheric Environment 43 (9), 1650-1659), such a priori information was introduced in the model as auxiliary terms of the object function to be minimized by the implementation of the so-called "pulling equations". ME-2 permitted to enhance the basic PMF solution (obtained by PMF2) identifying, beside the seven sources of PMF2, the road dust source which accounted for 6.9 μg m -3 (17%) in PM 10, 2.2 μg m -3 (8%) of PM 2.5 and 0.3 μg m -3 (2%) of PM 1. This reveals that resuspension was responsible of the 37%, 15% and 3% of total traffic emissions respectively in PM 10, PM 2.5 and PM 1. Therefore the overall traffic contribution resulted in 18 μg m -3 (46%) in PM 10, 14 μg m -3 (51%) in PM 2.5 and 8 μg m -3 (48%) in PM 1. In PMF2 this mass explained by road dust resuspension was redistributed among the rest of sources, increasing mostly the mineral, secondary nitrate and aged sea salt contributions.

Source Apportionment of Particulate Matter Collected Upwind and Downwind of a Steel Facility in Granite City, IL (USA)

NASA Astrophysics Data System (ADS)

Duvall, R. M.; Norris, G. A.; Willis, R. D.; Turner, J. R.; Kaleel, R.; Sweitzer, T.; Preston, B.; Hays, M. D.

2009-04-01

St. Louis is currently in nonattainment of the annual PM2.5 National Ambient Air Quality Standard (NAAQS). Granite City Steel Works (GSCW), located in Granite City, IL is considered to be a significant source impacting the St. Louis area and the largest PM2.5 point source contributor. Twelve grab samples were collected in and around the steel facility including the basic oxygen furnace, steel and iron slag crushing, coal pulverizing, baghouse dust, paved road dust, and unpaved road dust. The bulk samples were resuspended in a resuspension chamber using a PM2.5 cutpoint and collected on Teflon, quartz and polycarbonate filters. Fine particulate matter (PM) samples (12-hr and 24-hr) were collected upwind and downwind of GSCW from October 13 to December 13, 2007 to identify sources contributing to nonattainment in St. Louis. The samples were analyzed for trace metals (X-Ray Fluorescence), ions (Ion Chromatography), elemental and organic carbon (thermal optical analysis), and organic species (solvent extraction Gas Chromatography/Mass Spectrometry). Source apportionment was conducted using the EPA Chemical Mass Balance (CMB) Model (v 8.2). Major sources impacting the 12-hr samples included the blast oxygen furnace, secondary sulfate, and road dust. Higher excess steel and coke works contributions were associated with higher wind speeds (greater than 5 mph) and more variability in source impacts was observed. Major sources impacting the 24-hr samples included secondary sulfate and motor vehicles (diesel and gasoline). Contributions were similar between the coke and steel works sources. Disclaimer: Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

IMPLICATIONS OF PARTICULATE MATTER RESEARCH PROGRAM UPON EXPOSURE ASSESSMENT AND APPORTIONMENT AND ATTRIBUTION OF ENVIRONMENTAL EFFECTS

EPA Science Inventory

Recent personal exposure panel studies and monitoring programs addressing fine particulate matter (PM) and associated co-pollutants have elucidated the physical and statistical relationships between personal exposures, residential indoor concentrations (and sources), concentratio...

PMF5.0 vs. CMB8.2: An inter-comparison study based on the new European SPECIEUROPE database

NASA Astrophysics Data System (ADS)

Bove, Maria Chiara; Massabò, Dario; Prati, Paolo

2018-03-01

Receptor Models are tools widely adopted in source apportionment studies. We describe here an experiment in which we integrated two different approaches, i.e. Positive Matrix Factorization (PMF) and Chemical Mass Balance (CMB) to apportion a set of PM10 (i.e. Particulate Matter with aerodynamic diameter lower than 10 μm) concentration values. The study was performed in the city of Genoa (Italy): a sampling campaign was carried out collecting daily PM10 samples for about two months in an urban background site. PM10 was collected on Quartz fiber filters by a low-volume sampler. A quite complete speciation of PM samples was obtained via Energy Dispersive-X Ray Fluorescence (ED-XRF, for elements), Ionic Chromatography (IC, for major ions and levoglucosan), thermo-optical Analysis (TOT, for organic and elemental carbon). The chemical analyses provided the input database for source apportionment by both PMF and CMB. Source profiles were directly calculated from the input data by PMF while in the CMB runs they were first calculated by averaging the profiles of similar sources collected in the European database SPECIEUROPE. Differences between the two receptor models emerged in particular with PM10 sources linked to very local processes. For this reason, PMF source profiles were adopted in refined CMB runs thus testing a new hybrid approach. Finally, PMF and the "tuned" CMB showed a better agreement even if some discrepancies could not completely been resolved. In this work, we compared the results coming from the last available PMF and CMB versions applied on a set of PM10 samples. Input profiles used in CMB analysis were obtained by averaging the profiles of the new European SPECIEUROPE database. The main differences between PMF and CMB results were linked to very local processes: we obtained the best solution by integrating the two different approaches with the implementation of some output PMF profiles to CMB runs.

Ft. McHenry tunnel study: Source profiles and mercury emissions from diesel and gasoline powered vehicles

NASA Astrophysics Data System (ADS)

Landis, Matthew S.; Lewis, Charles W.; Stevens, Robert K.; Keeler, Gerald J.; Dvonch, J. Timothy; Tremblay, Raphael T.

During the fall of 1998, the US Environmental Protection Agency and the Florida Department of Environmental Protection sponsored a 7-day study at the Ft. McHenry tunnel in Baltimore, MD with the objective of obtaining PM 2.5 vehicle source profiles for use in atmospheric mercury source apportionment studies. PM 2.5 emission profiles from gasoline and diesel powered vehicles were developed from analysis of trace elements, polycyclic aromatic hydrocarbons (PAH), and condensed aliphatic hydrocarbons. PM 2.5 samples were collected using commercially available sampling systems and were extracted and analyzed using conventional well-established methods. Both inorganic and organic profiles were sufficiently unique to mathematically discriminate the contributions from each source type using a chemical mass balance source apportionment approach. However, only the organic source profiles provided unique PAH tracers (e.g., fluoranthene, pyrene, and chrysene) for diesel combustion that could be used to identify source contributions generated using multivariate statistical receptor modeling approaches. In addition, the study found significant emission of gaseous elemental mercury (Hg 0), divalent reactive gaseous mercury (RGM), and particulate mercury (Hg(p)) from gasoline but not from diesel powered motor vehicles. Fuel analysis supported the tunnel measurement results showing that total mercury content in all grades of gasoline (284±108 ng L -1) was substantially higher than total mercury content in diesel fuel (62±37 ng L -1) collected contemporaneously at local Baltimore retailers.

Source Apportionment and Elemental Composition of PM2.5 and PM10 in Jeddah City, Saudi Arabia.

PubMed

Khodeir, Mamdouh; Shamy, Magdy; Alghamdi, Mansour; Zhong, Mianhua; Sun, Hong; Costa, Max; Chen, Lung-Chi; Maciejczyk, Polina

2012-07-01

This paper presents the first comprehensive investigation of PM2.5 and PM10 composition and sources in Saudi Arabia. We conducted a multi-week multiple sites sampling campaign in Jeddah between June and September, 2011, and analyzed samples by XRF. The overall mean mass concentration was 28.4 ± 25.4 μg/m 3 for PM2.5 and 87.3 ± 47.3 μg/m 3 for PM10, with significant temporal and spatial variability. The average ratio of PM2.5/PM10 was 0.33. Chemical composition data were modeled using factor analysis with varimax orthogonal rotation to determine five and four particle source categories contributing significant amount of for PM2.5 and PM10 mass, respectively. In both PM2.5 and PM10 sources were (1) heavy oil combustion characterized by high Ni and V; (2) resuspended soil characterized by high concentrations of Ca, Fe, Al, and Si; and (3) marine aerosol. The two other sources in PM2.5 were (4) Cu/Zn source; (5) traffic source identified by presence of Pb, Br, and Se; while in PM10 it was a mixed industrial source. To estimate the mass contributions of each individual source category, the CAPs mass concentration was regressed against the factor scores. Cumulatively, resuspended soil and oil combustion contributed 77 and 82% mass of PM2.5 and PM10, respectively.

Source Apportionment and Elemental Composition of PM2.5 and PM10 in Jeddah City, Saudi Arabia

PubMed Central

Khodeir, Mamdouh; Shamy, Magdy; Alghamdi, Mansour; Zhong, Mianhua; Sun, Hong; Costa, Max; Chen, Lung-Chi; Maciejczyk, Polina

2014-01-01

This paper presents the first comprehensive investigation of PM2.5 and PM10 composition and sources in Saudi Arabia. We conducted a multi-week multiple sites sampling campaign in Jeddah between June and September, 2011, and analyzed samples by XRF. The overall mean mass concentration was 28.4 ± 25.4 μg/m3 for PM2.5 and 87.3 ± 47.3 μg/m3 for PM10, with significant temporal and spatial variability. The average ratio of PM2.5/PM10 was 0.33. Chemical composition data were modeled using factor analysis with varimax orthogonal rotation to determine five and four particle source categories contributing significant amount of for PM2.5 and PM10 mass, respectively. In both PM2.5 and PM10 sources were (1) heavy oil combustion characterized by high Ni and V; (2) resuspended soil characterized by high concentrations of Ca, Fe, Al, and Si; and (3) marine aerosol. The two other sources in PM2.5 were (4) Cu/Zn source; (5) traffic source identified by presence of Pb, Br, and Se; while in PM10 it was a mixed industrial source. To estimate the mass contributions of each individual source category, the CAPs mass concentration was regressed against the factor scores. Cumulatively, resuspended soil and oil combustion contributed 77 and 82% mass of PM2.5 and PM10, respectively. PMID:24634602

Fine particulate matter in the tropical environment: monsoonal effects, source apportionment, and health risk assessment

NASA Astrophysics Data System (ADS)

Khan, M. F.; Latif, M. T.; Saw, W. H.; Amil, N.; Nadzir, M. S. M.; Sahani, M.; Tahir, N. M.; Chung, J. X.

2016-01-01

The health implications of PM2.5 in the tropical region of Southeast Asia (SEA) are significant as PM2.5 can pose serious health concerns. PM2.5 concentration and sources here are strongly influenced by changes in the monsoon regime from the south-west quadrant to the north-east quadrant in the region. In this work, PM2.5 samples were collected at a semi-urban area using a high-volume air sampler at different seasons on 24 h basis. Analysis of trace elements and water-soluble ions was performed using inductively coupled plasma mass spectroscopy (ICP-MS) and ion chromatography (IC), respectively. Apportionment analysis of PM2.5 was carried out using the United States Environmental Protection Agency (US EPA) positive matrix factorization (PMF) 5.0 and a mass closure model. We quantitatively characterized the health risks posed to human populations through the inhalation of selected heavy metals in PM2.5. 48 % of the samples collected exceeded the World Health Organization (WHO) 24 h PM2.5 guideline but only 19 % of the samples exceeded 24 h US EPA National Ambient Air Quality Standard (NAAQS). The PM2.5 concentration was slightly higher during the north-east monsoon compared to south-west monsoon. The main trace metals identified were As, Pb, Cd, Ni, Mn, V, and Cr while the main ions were SO42-, NO3-, NH4+, and Na. The mass closure model identified four major sources of PM2.5 that account for 55 % of total mass balance. The four sources are mineral matter (MIN) (35 %), secondary inorganic aerosol (SIA) (11 %), sea salt (SS) (7 %), and trace elements (TE) (2 %). PMF 5.0 elucidated five potential sources: motor vehicle emissions coupled with biomass burning (31 %) were the most dominant, followed by marine/sulfate aerosol (20 %), coal burning (19 %), nitrate aerosol (17 %), and mineral/road dust (13 %). The hazard quotient (HQ) for four selected metals (Pb, As, Cd, and Ni) in PM2.5 mass was highest in PM2.5 mass from the coal burning source and least in PM2.5 mass originating from the mineral/road dust source. The main carcinogenic heavy metal of concern to health at the current location was As; the other heavy metals (Ni, Pb, and Cd) did not pose a significant cancer risk in PM2.5 mass concentration. Overall, the associated lifetime cancer risk posed by the exposure of hazardous metals in PM2.5 is 3-4 per 1 000 000 people at this location.

Source apportionment with uncertainty estimates of fine particulate matter in Ostrava, Czech Republic using Positive Matrix Factorization

EPA Science Inventory

A 14-week investigation during a warm and cold seasons was conducted to improve understanding of air pollution sources that might be impacting air quality in Ostrava, the Czech Republic. Fine particulate matter (PM2.5) samples were collected in consecutive 12-h day and night incr...

EVALUATION OF THE CMB AND PMF MODELS USING ORGANIC MOLECULAR MARKERS IN FINE PARTICULATE MATTER COLLECTED DURING THE PITTSBURGH AIR QUALITY STUDY

EPA Science Inventory

This research investigated different strategies for source apportionment of airborne fine particulate matter (PM2.5) collected as part of the Pittsburgh Air Quality Study. Two source receptor models were used, the EPA Chemical Mass Balance 8.2 (CMB) and EPA Positive Matrix Facto...

Chemical Composition and Source Apportionment of high temporal resolution PM1 data for January-August 2017 in Delhi, India

NASA Astrophysics Data System (ADS)

Bhandari, S.; Wang, D. S.; Gani, S.; Seraj, S.; Arub, Z.; Habib, G.; Apte, J.; Hildebrandt Ruiz, L.

2017-12-01

Exposure to fine particulate matter (PM) poses significant health risks, especially to residents in heavily populated areas. The current understanding of the sources and dynamics of PM pollution in developing countries like India is limited. Delhi, India is the second most populated city in the world that has extremely high winter PM concentrations and frequent severe pollution episodes. This study reports on composition measurements of submicron aerosol at 1 minute time resolution from January to August of 2017, collected at the Indian Institute of Technology Delhi using an Aerodyne Aerosol Chemical Speciation Monitor (ACSM) and black carbon (BC) measurements using an Aethalometer. Source apportionment was conducted on organic and inorganic mass spectra measured by the ACSM and black carbon data measured using Positive Matrix Factorization (PMF). High concentrations of particulate matter were observed with total PM1 at times exceeding 200 µg m-3 in winter. A significant drop in PM1 concentrations was observed in the winter-spring transition. As observed elsewhere, organic species dominated the submicron mass, contributing 60% of the total mass over the duration of the campaign. However, this fractional contribution varied substantially over the day: from 48% early in the morning to 73% late at night. Along with diurnal variation in total PM1 mass loadings, particulate chloride levels also exhibited a strong diurnal cycle, with concentrations as high as 50 µg m-3 observed in the early mornings of January 2017. Literature review on identification of winter chloride sources in Delhi points to local and regional sources such as biomass/open-waste burning and coal combustion. PMF receptor modeling identified several factors with distinct diurnal patterns. While hydrocarbon-like organic aerosol (HOA) factor has the largest mass fraction contribution, PMF results consistently suggest chloride presence as attributable to ammonium chloride. Interestingly, aerosol neutralization characterization shows an apparent acidity of aerosols. These results point to substantial differences in aerosol composition in Indian cities in comparison to cities around the world, especially with regards to the abundance of particulate chloride, and provide insights into the sources of PM1 measured in Delhi.

Comparison of source apportionment of PM2.5 using receptor models in the main hub port city of East Asia: Busan

NASA Astrophysics Data System (ADS)

Jeong, Ju-Hee; Shon, Zang-Ho; Kang, Minsung; Song, Sang-Keun; Kim, Yoo-Keun; Park, Jinsoo; Kim, Hyunjae

2017-01-01

The contributions of various PM2.5 emission sources to ambient PM2.5 levels during 2013 in the main hub port city (Busan, South Korea) of East Asia was quantified using several receptor modeling techniques. Three receptor models of principal component analysis/absolute principal component score (PCA/APCS), positive matrix factorization (PMF), and chemical mass balance (CMB) were used to apportion the source of PM2.5 obtained from the target city. The results of the receptor models indicated that the secondary formation of PM2.5 was the dominant (45-60%) contributor to PM2.5 levels in the port city of Busan. The PMF and PCA/APCS suggested that ship emission was a non-negligible contributor of PM2.5 (up to about 10%) in the study area, whereas it was a negligible contributor based on CMB. The magnitude of source contribution estimates to PM2.5 levels differed significantly among these three models due to their limitations (e.g., PM2.5 emission source profiles and restrictions of the models). Potential source contribution function and concentration-weighted trajectory analyses indicated that long-range transport from sources in the eastern China and Yellow Sea contributed significantly to the level of PM2.5 in Busan.

Source apportionment of PM2.5 for supporting control strategies in the Monterrey Metropolitan Area, Mexico.

PubMed

Martínez-Cinco, Marco; Santos-Guzmán, Jesús; Mejía-Velázquez, Gerardo

2016-06-01

The Monterrey Metropolitan Area (MMA) in Northeast Mexico has shown high PM2.5 concentrations since 2003. The data shows that the annual average concentration exceeds from 2 to 3 times the Mexican PM2.5 annual air quality standard of 12 µg/m(3). In a previous work we studied the chemical characterization of PM2.5 in two sites of the MMA during the winter season. Among the most important components we found ammonium sulfate and nitrate, elemental and organic carbon, and crustal matter. In this work we present the results of a second chemical characterization study performed during the summer time and the application of the chemical mass balance (CMB) model to determine the source apportionment of air pollutants in the region. The chemical analysis results show that the chemical composition of PM2.5 is similar in both sites and periods of the year. The results of the chemical analysis and the CMB model show that industrial, traffic, and combustion activities in the area are the major sources of primary PM2.5 and precursor gases of secondary inorganic and organic aerosol (SO2, NOx, NH3, and volatile organic compounds [VOCs]). We also found that black carbon and organic carbon are important components of PM2.5 in the MMA. These results are consistent with the MMA emission inventory that reports as major sources of particles and SO2 a refinery and fuel combustion, as well as nitrogen oxides and ammonium from transportation and industrial activities in the MMA and ammonium form agricultural activities in the state. The results of this work are important to identify and support effective actions to reduce direct emissions of PM2.5 and its precursor gases to improve air quality in the MMA. The Monterrey Metropolitan Area (MMA) has been classified as the most air-polluted area in Mexico by the World Health Organization (WHO). Effective actions need to be taken to control primary sources of PM2.5 and its precursors, reducing health risks on the population exposed and their associated costs. The results of this study identify the main sources and their estimated contribution to PM2.5 mass concentration, providing valuable information to the local environmental authorities to take decisions on PM2.5 control strategies in the MMA.

Winter-time size distribution and source apportionment of total suspended particulate matter and associated metals in Delhi

NASA Astrophysics Data System (ADS)

Srivastava, Arun; Gupta, Sandeep; Jain, V. K.

2009-03-01

A study of the winter time size distribution and source apportionment of total suspended particulate matter (TSPM) and associated heavy metal concentrations have been carried out for the city of Delhi. This study is important from the point of view of implementation of compressed natural gas (CNG) as alternate of diesel fuel in the public transport system in 2001 to reduce the pollution level. TSPM were collected using a five-stage cascade impactor at six sites in the winters of 2005-06. The results of size distribution indicate that a major portion (~ 40%) of TSPM concentration is in the form of PM0.7 (< 0.7 μm). Similar trends were observed with most of the heavy metals associated with various size fractions of TSPM. A very good correlation between coarse and fine size fraction of TSPM was observed. It was also observed that the metals associated with coarse particles have more chances of correlation with other metals; rather they are associated with fine particles. Source apportionment was carried out separately in coarse and fine size modes of TSPM by Chemical Mass Balance Receptor Model (CMB8) as well as by Principle Component Analysis (PCA) of SPSS. Source apportionment by PCA reveals that there are two major sources (possibly vehicular and crustal re-suspension) in both coarse and fine size fractions. Results obtained by CMB8 show the dominance of vehicular pollutants and crustal dust in fine and coarse size mode respectively. Noticeably the dominance of vehicular pollutants are now confined to fine size only whilst during pre CNG era it dominated both coarse and fine size mode. An increase of 42.5, 44.4, 48.2, 38.6 and 38.9% in the concentrations of TSPM, PM10.9, coarse particles, fine particles and lead respectively was observed during pre (2001) to post CNG (2005-06) period.

Source Apportionment Analysis of Measured Fine Particulate Matter in a Semi-Arid Urban Airshed in Corpus Christi, U.S.A

NASA Astrophysics Data System (ADS)

Karnae, Saritha; John, Kuruvilla

2010-05-01

Corpus Christi is an industrialized urban area of South Texas that is currently in compliance with the National Ambient Air Quality Standards (NAAQS) for PM2.5 as set by the United States Environmental Protection Agency (U.S EPA). However a gradual increase in the annual and 24-hour PM2.5 concentrations was noted since 2001. In this study, principal component analysis/absolute principal component scores (PCA/APCS) was used as a source apportionment technique to identify key source categories that affected the measured PM2.5 concentrations at a continuous ambient monitoring station (CAMS) 04 maintained and operated by Texas Commission on Environmental Quality (TCEQ) during 2000 through 2007. Cluster analysis using computed backward trajectories was performed on days with high PM2.5 concentrations. The elevated PM days were heavily influenced by transported levels of PM during three types of episodic events including smoke plumes due to biomass burning in Mexico and Central America during April and May, sub-Saharan dust transport from Africa during June and July, and regional haze transport from highly industrialized areas of Texas and surrounding Midwestern states during September. Pyrotechnic emissions during local firework events during the New Year day celebrations under stagnant meteorological conditions also resulted in elevated PM2.5 concentrations. PCA/APCS identified five key source categories that accounted for 78% of the variance in the PM2.5 concentrations measured within the urban airshed. Secondary sulphates were identified to be the major contributor accounting for 46% of the apportioned mass. This was followed by mobile sources which accounted for 26%. The other sources that were identified by PCA/APCS included crustal dust, a commingled source of biomass burning and sea salt, and secondary nitrates. Increase in secondary sulphates was observed during August and September typically associated with the long range transport of continental haze from industrialized areas in Texas and surrounding states. Mobile source contributions increased during the winter months due to an increase in tourism related activities in the area. Biomass burning in Mexico and Central America during April and May contributed to elevated PM2.5 concentrations observed in the Corpus Christi urban airshed.

Fugitive Dust Emissions: Development of a Real-time Monitor

DTIC Science & Technology

2011-10-01

the mechanical disturbance of soils which injects particles into the air. Common sources of FD include vehicles driving on unpaved roads...agricultural tilling, and heavy construction operations. For these sources the dust-generation process is caused by two basic physical phenomena...visibility, source apportionment , etc. The PM10 standard set by the U.S. Environmental Protection Agency in 1987 is an example of size-selective

Spatial and temporal variability of fine particle composition and source types in five cities of Connecticut and Massachusetts

PubMed Central

Lee, Hyung Joo; Gent, Janneane F.; Leaderer, Brian P.; Koutrakis, Petros

2011-01-01

To protect public health from PM2.5 air pollution, it is critical to identify the source types of PM2.5 mass and chemical components associated with higher risks of adverse health outcomes. Source apportionment modeling using Positive Matrix Factorization (PMF), was used to identify PM2.5 source types and quantify the source contributions to PM2.5 in five cities of Connecticut and Massachusetts. Spatial and temporal variability of PM2.5 mass, components and source contributions were investigated. PMF analysis identified five source types: regional pollution as traced by sulfur, motor vehicle, road dust, oil combustion and sea salt. The sulfur-related regional pollution and traffic source type were major contributors to PM2.5. Due to sparse ground-level PM2.5 monitoring sites, current epidemiological studies are susceptible to exposure measurement errors. The higher correlations in concentrations and source contributions between different locations suggest less spatial variability, resulting in less exposure measurement errors. When concentrations and/or contributions were compared to regional averages, correlations were generally higher than between-site correlations. This suggests that for assigning exposures for health effects studies, using regional average concentrations or contributions from several PM2.5 monitors is more reliable than using data from the nearest central monitor. PMID:21429560

Characteristics and source apportionment of PM2.5 during persistent extreme haze events in Chengdu, southwest China

NASA Astrophysics Data System (ADS)

Li, L.; Liu, S.

2017-12-01

Based on detailed data from Chengdu Plain (CP) from 6 January to 16 January 2015 , two typical haze episodes were analyzed to clarify the haze formation mechanism in winter. Weather conditions, chemical compositions, secondary pollutant transformation, optical properties of aerosols, the potential source contribution function (PSCF) and source apportionment were studied. The planetary boundary layer (PBL) height decreased distinctly during the haze episodes and restrained air pollutant vertical dispersion. As the haze worsened, the value of PBL × PM2.5 increased notably. The [NO3-]/[SO42-] ratio was 0.61, 0.76 and 0.88 during a non-haze period, episode 1 and episode 2, respectively, indicating that the mobile source of the air pollution is increasingly predominant in Chengdu. Water vapor also played a vital role in the formation of haze by accelerating the chemical transformation of secondary pollutants, leading to the hygroscopic growth of aerosols. The PSCF and backward trajectories of the air masses indicated that the pollution mainly came from the south. The secondary inorganic aerosols, vehicle emissions, coal combustion, biomass burning, industry, and dust contributed 34.1%, 24.1%, 12.7%, 12.3%, 7.6%, and 7.2% to PM2.5 masses in episode 1 and 28.9%, 23.1%, 9.4%, 9.5%, 20.3% and 7.5% in episode 2.

Characteristics and source apportionment of PM2.5 during persistent extreme haze events in Chengdu, southwest China.

PubMed

Li, Lulu; Tan, Qinwen; Zhang, Yuanhang; Feng, Miao; Qu, Yu; An, Junling; Liu, Xingang

2017-11-01

Based on detailed data from Chengdu Plain (CP) from 6 January to 16 January, two typical haze episodes were analyzed to clarify the haze formation mechanism in winter. Weather conditions, chemical compositions, secondary pollutant transformation, optical properties of aerosols, the potential source contribution function (PSCF) and source apportionment were studied. The planetary boundary layer (PBL) height decreased distinctly during the haze episodes and restrained air pollutant vertical dispersion. As the haze worsened, the value of PBL × PM 2.5 increased notably. The [NO 3 - ]/[SO 4 2- ] ratio was 0.61, 0.76 and 0.88 during a non-haze period, episode 1 and episode 2, respectively, indicating that the mobile source of the air pollution is increasingly predominant in Chengdu. Water vapor also played a vital role in the formation of haze by accelerating the chemical transformation of secondary pollutants, leading to the hygroscopic growth of aerosols. The PSCF and backward trajectories of the air masses indicated that the pollution mainly came from the south. The secondary inorganic aerosols, vehicle emissions, coal combustion, biomass burning, industry, and dust contributed 34.1%, 24.1%, 12.7%, 12.3%, 7.6%, and 7.2% to PM 2.5 masses in episode 1 and 28.9%, 23.1%, 9.4%, 9.5%, 20.3% and 7.5% in episode 2. Copyright © 2017 Elsevier Ltd. All rights reserved.

Open air mineral treatment operations and ambient air quality: assessment and source apportionment.

PubMed

Escudero, M; Alastuey, A; Moreno, T; Querol, X; Pérez, P

2012-11-01

We present a methodology for evaluating and quantifying the impact of inhalable mineral dust resuspension close to a potentially important industrial point source, in this case an open air plant producing sand, flux and kaolin in the Capuchinos district of Alcañiz (Teruel, NE Spain). PM(10) levels at Capuchinos were initially high (42 μg m(-3) as the annual average with 91 exceedances of the EU daily limit value during 2007) but subsequently decreased (26 μg m(-3) with 16 exceedances in 2010) due to a reduced demand for minerals from the ceramic industry and construction sector during the first stages of the economic crisis. Back trajectory and local wind pattern analyses revealed only limited contribution from exotic PM sources such as African dust intrusions whereas there was clearly a strong link with the mineral stockpiles of the local industry. This link was reinforced by chemical and mineral speciation and source apportionment analysis which showed a dominance of mineral matter (sum of CO(3)(2-), SiO(2), Al(2)O(3), Ca, Fe, K, Mg, P, and Ti: mostly aluminosilicates) which in 2007 contributed 76% of the PM(10) mass (44 μg m(-3) on average). The contribution from Secondary Inorganic Aerosols (SIA, sum of SO(4)(2-), NO(3)(-) and NH(4)(+)) reached 8.4 μg m(-3), accounting for 14% of the PM(10) mass, similar to the amount of calcareous road dust estimated to be present (8 μg m(-3); 13%). Organic matter and elemental carbon contributed 5.3 μg m(-3) (9%) whereas marine aerosol (Na + Cl) levels were minor with an average concentration of 0.4 μg m(-3) (1% of the PM(10) mass). Finally, chemical and mineralogical analysis of stockpile samples and comparison with filter samples confirmed the local industry to be the major source of ambient PM(10) in the area.

Biomass burning in the Amazon region: Aerosol source apportionment and associated health risk assessment

NASA Astrophysics Data System (ADS)

de Oliveira Alves, Nilmara; Brito, Joel; Caumo, Sofia; Arana, Andrea; de Souza Hacon, Sandra; Artaxo, Paulo; Hillamo, Risto; Teinilä, Kimmo; Batistuzzo de Medeiros, Silvia Regina; de Castro Vasconcellos, Pérola

2015-11-01

The Brazilian Amazon represents about 40% of the world's remaining tropical rainforest. However, human activities have become important drivers of disturbance in that region. The majority of forest fire hotspots in the Amazon arc due to deforestation are impacting the health of the local population of over 10 million inhabitants. In this study we characterize western Amazonia biomass burning emissions through the quantification of 14 Polycyclic Aromatic Hydrocarbons (PAHs), Organic Carbon, Elemental Carbon and unique tracers of biomass burning such as levoglucosan. From the PAHs dataset a toxic equivalence factor is calculated estimating the carcinogenic and mutagenic potential of biomass burning emissions during the studied period. Peak concentration of PM10 during the dry seasons was observed to reach 60 μg m-3 on the 24 h average. Conversely, PM10 was relatively constant throughout the wet season indicating an overall stable balance between aerosol sources and sinks within the filter sampling resolution. Similar behavior is identified for OC and EC components. Levoglucosan was found in significant concentrations (up to 4 μg m-3) during the dry season. Correspondingly, the estimated lung cancer risk calculated during the dry seasons largely exceeded the WHO health-based guideline. A source apportionment study was carried out through the use of Absolute Principal Factor Analysis (APFA), identifying a three-factor solution. The biomass burning factor is found to be the dominating aerosol source, having 75.4% of PM10 loading. The second factor depicts an important contribution of several PAHs without a single source class and therefore was considered as mixed sources factor, contributing to 6.3% of PM10. The third factor was mainly associated with fossil fuel combustion emissions, contributing to 18.4% of PM10. This work enhances the knowledge of aerosol sources and its impact on climate variability and local population, on a site representative of the deforestation which occupies a significant fraction of the Amazon basin.

Fine particulates over South Asia: Review and meta-analysis of PM2.5 source apportionment through receptor model.

PubMed

Singh, Nandita; Murari, Vishnu; Kumar, Manish; Barman, S C; Banerjee, Tirthankar

2017-04-01

Fine particulates (PM 2.5 ) constitute dominant proportion of airborne particulates and have been often associated with human health disorders, changes in regional climate, hydrological cycle and more recently to food security. Intrinsic properties of particulates are direct function of sources. This initiates the necessity of conducting a comprehensive review on PM 2.5 sources over South Asia which in turn may be valuable to develop strategies for emission control. Particulate source apportionment (SA) through receptor models is one of the existing tool to quantify contribution of particulate sources. Review of 51 SA studies were performed of which 48 (94%) were appeared within a span of 2007-2016. Almost half of SA studies (55%) were found concentrated over few typical urban stations (Delhi, Dhaka, Mumbai, Agra and Lahore). Due to lack of local particulate source profile and emission inventory, positive matrix factorization and principal component analysis (62% of studies) were the primary choices, followed by chemical mass balance (CMB, 18%). Metallic species were most regularly used as source tracers while use of organic molecular markers and gas-to-particle conversion were minimum. Among all the SA sites, vehicular emissions (mean ± sd: 37 ± 20%) emerged as most dominating PM 2.5 source followed by industrial emissions (23 ± 16%), secondary aerosols (22 ± 12%) and natural sources (20 ± 15%). Vehicular emissions (39 ± 24%) also identified as dominating source for highly polluted sites (PM 2.5 >100 μgm -3 , n = 15) while site specific influence of either or in combination of industrial, secondary aerosols and natural sources were recognized. Source specific trends were considerably varied in terms of region and seasonality. Both natural and industrial sources were most influential over Pakistan and Afghanistan while over Indo-Gangetic plain, vehicular, natural and industrial emissions appeared dominant. Influence of vehicular emission was found single dominating source over southern part while over Bangladesh, both vehicular, biomass burning and industrial sources were significant. Copyright © 2016 Elsevier Ltd. All rights reserved.

Source apportionment and water solubility of metals in size segregated particles in urban environments.

PubMed

Jiang, Sabrina Yanan; Kaul, Daya S; Yang, Fenhuan; Sun, Li; Ning, Zhi

2015-11-15

Metals in atmospheric particulate matter (PM) have been associated with various adverse health effects. Different factors contributing to the characterization and distribution of atmospheric metals in urban environments lead to uncertainty of the understanding of their impact on public health. However, few studies have provided a comprehensive picture of the spatial and seasonal variability of metal concentration, solubility and size distribution, all of which have important roles in their contribution to health effects. This study presents an experimental investigation on the characteristics of metals in PM2.5 and coarse PM in two seasons from four urban sites in Hong Kong. The PM samples were extracted separately with aqua regia and water, and a total of sixteen elements were analyzed using ICP-MS and ICP-OES to determine the size segregated concentration and solubility of metals. The concentrations of major metals were distributed in similar patterns with the same order of magnitude among different urban sites. Source apportionment using Positive Matrix Factorization (PMF) indicated that three sources namely road dust, vehicular exhaust and ship emission are major contributors to the urban atmospheric metal concentrations in Hong Kong with distinctly different profiles between coarse PM and PM2.5 fractions. The individual metals were assigned to different sources, consistent with literature documentation, except potassium emerging with substantial contribution from vehicle exhaust emission. Literature data from past studies on both local and other cities were compared to the results from the present study to investigate the impact of different emission sources and control policies on metal distribution in urban atmosphere. A large variation of solubility among the metals reflected that the majority of metals in PM2.5 were more soluble than those in coarse PM indicating size dependent chemical states of metals. The data from this study provides a rich dataset of metals in urban atmosphere and can be useful for targeted emission control to mitigate the adverse impact of metallic pollution on public health. Copyright © 2015 Elsevier B.V. All rights reserved.

Source apportionment of particulate matter in a South Asian Mega City: A case study of Karachi

NASA Astrophysics Data System (ADS)

Shahid, imran

2016-04-01

Pakistan is facing unabated air pollution as a major issue and its cities are more vulnerable as compared to urban centers in the developed world. During the last few decades, there has been a rapid increase in population, urbanization, industrialization, transportation and other human activities. In year June 2015 heat wave in largest South Asian mega city Karachi more than 1500 people died in one week. Unfortunately no air quality monitoring system is operation in any city of Pakistan. There is a sharp increase in both the variety and quantity of air pollutants and their corresponding sources. In this study contributions of different sources to particulate matter concentration has estimated in urban area of Karachi. Carbonaceous species (elemental carbon, organic carbon, carbonate carbon), soluble ions (Ca++, Mg++, Na+, K+, NH4+, Cl-, NO3-, SO4--), saccharides (levoglucosan, galactosan, mannosan, sucrose, fructose, glucose, arabitol and mannitol) were measured in atmospheric fine (PM2.5) and coarse (PM10) particles collected under pre-monsoon conditions (March - April 2009) at an urban site in Karachi (Pakistan). Average concentrations of PM2.5 were 75μg/m3 and of PM10 437μg/m3. The large difference between PM10 and PM2.5 originated predominantly from mineral dust. "Calcareous dust" and „siliceous dust" were the overall dominating material in PM, with 46% contribution to PM2.5 and 78% to PM10-2.5. 20 Combustion particles and secondary organics (EC+OM) comprised 23% of PM2.5 and 6% of PM10-2.5. EC, as well as OC ambient levels were higher (59% and 56%) in PM10-2.5 than in 22 PM2.5. Biomass burning contributed about 3% to PM2.5, and had a share of about 13% of "EC+OM" in PM2.5. The impact of bioaerosol (fungal spores) was minor and had a share of 1 and 2% of the OC in the PM2.5 and PM10-2.5 size fractions. Of secondary inorganic constituents (NH4)2SO4 contributes 4.4% to PM2.5 and no detectable quantity to PM10-2.5. The sea salt contribution is about 2% both to PM2.5 and PM10-2.5. In order to make air quality better and risk free in South Asian cities a comprehensive and integrated regional effort is required that include continuous air quality monitoring, source apportionment and implementation of regional air quality policies.

Source contribution of PM₂.₅ at different locations on the Malaysian Peninsula.

PubMed

Ee-Ling, Ooi; Mustaffa, Nur Ili Hamizah; Amil, Norhaniza; Khan, Md Firoz; Latif, Mohd Talib

2015-04-01

This study determined the source contribution of PM2.5 (particulate matter <2.5 μm) in air at three locations on the Malaysian Peninsula. PM2.5 samples were collected using a high volume sampler equipped with quartz filters. Ion chromatography was used to determine the ionic composition of the samples and inductively coupled plasma mass spectrometry was used to determine the concentrations of heavy metals. Principal component analysis with multilinear regressions were used to identify the possible sources of PM2.5. The range of PM2.5 was between 10 ± 3 and 30 ± 7 µg m(-3). Sulfate (SO4 (2-)) was the major ionic compound detected and zinc was found to dominate the heavy metals. Source apportionment analysis revealed that motor vehicle and soil dust dominated the composition of PM2.5 in the urban area. Domestic waste combustion dominated in the suburban area, while biomass burning dominated in the rural area.

Source apportionment analysis of air pollutants using CMAQ/BFM for national air quality management policy over Republic of Korea.

NASA Astrophysics Data System (ADS)

Moon, N.; Kim, S.; Seo, J.; Lee, Y. J.

2017-12-01

Recently, the Korean government is focusing on solving air pollution problem such as fine particulate matter and ozone. Korea has high population density and concentrated industrial complex in its limited land space. For better air quality management, it is important to understand source and contribution relation to target pollutant. The air quality analysis representing the mutual contribution among the local regions enables to understand the substantive state of the air quality of a region in association with neighboring regions. Under this background, the source apportionment of PM10, PM2.5, O3, NO2, SO2 using WRF and CMAQ/BFM was analyzed over Korea and BFM was applied to mobile, area and point sources in each local government. The contribution rate from neighboring region showed different pattern for each pollutant. In case of primary pollutants such as NO2, SO2, local source contribution is dominant, on the other hand secondary pollutants case especially O3, contribution from neighboring region is higher than that from source region itself. Local source contribution to PM10 showed 20-25% and the contribution rate to O3 has big difference with different meteorological condition year after year. From this study, we tried to estimate the conversion rate between source (NOx, VOC, SO2, NH3, PMC, PM2.5, CO) and concentration (PM10, PM2.5, O3, NO2, SO2,) by regional group over Korea. The result can contribute to the decision-making process of important national planning related to large-scale industrial developments and energy supply policies (eg., operations of coal-fired power plants and diesel cars) and emission control plan, where many controversies and concerns are currently concentrated among local governments in Korea. With this kind of approach, various environmental and social problems related to air quality can also be identified early so that a sustainable and environmentally sound plan can be established by providing data infrastructures to be utilized by central government agencies, local governments, and even private sectors.

Source apportionment studies on particulate matter (PM10 and PM2.5) in ambient air of urban Mangalore, India.

PubMed

Kalaiarasan, Gopinath; Balakrishnan, Raj Mohan; Sethunath, Neethu Anitha; Manoharan, Sivamoorthy

2018-07-01

Particulate matter (PM 10 and PM 2.5 ) samples were collected from six sites in urban Mangalore and the mass concentrations for PM 10 and PM 2.5 were measured using gravimetric technique. The measurements were found to exceed the national ambient air quality standards (NAAQS) limits, with the highest concentration of 231.5 μg/m 3 for PM 10 particles at Town hall and 120.3 μg/m 3 for PM 2.5 particles at KMC Attavar. The elemental analysis using inductively coupled plasma optical emission spectrophotometer (ICPOES) revealed twelve different elements (As, Ba, Cd, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Sr and Zn) for PM 10 particles and nine different elements (Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sr and Zn) for PM 2.5 particles. Similarly, ionic composition of these samples measured by ion chromatography (IC) divulged nine different ions (F - , Cl - , NO 3 - , PO 4 3- , SO 4 2- , Na + , K + , Mg 2+ and Ca 2+ ) for PM 10 particles and ten different ions (F - , Cl - , NO 3 - , PO 4 3- , SO 4 2- , Na + , NH 4 + , K + , Mg 2+ and Ca 2+ ) for PM 2.5 particles. The source apportionment study of PM 10 and PM 2.5 for urban Mangalore in accordance with these six sample sites using chemical mass balance model (CMBv8.2) revealed nine and twelve predominant contributors for both PM 10 and PM 2.5 , respectively. The highest contributor of PM 10 was found to be paved road dust followed by diesel and gasoline vehicle emissions. Correspondingly, PM 2.5 was found to be contributed mainly from two-wheeler vehicle emissions followed by four-wheeler and heavy vehicle emissions (diesel vehicles). The current study depicts that the PM 10 and PM 2.5 in ambient air of Mangalore region has 70% of its contribution from vehicular emissions (both exhaust and non-exhaust). Copyright © 2018 Elsevier Ltd. All rights reserved.

Source apportionment of organic compounds in Berlin using positive matrix factorization - assessing the impact of biogenic aerosol and biomass burning on urban particulate matter.

PubMed

Wagener, Sandra; Langner, Marcel; Hansen, Ute; Moriske, Heinz-Jörn; Endlicher, Wilfried R

2012-10-01

Source apportionment of 13 organic compounds, elemental carbon and organic carbon of ambient PM(10) and PM(1) was performed with positive matrix factorization (PMF). Samples were collected at three sites characterized by different vegetation influences in Berlin, Germany in 2010. The aim was to determine organic, mainly biogenic sources and their impact on urban aerosol collected in a densely populated region. A 6-factor solution provided the best data fit for both PM-fractions, allowing the sources isoprene- and α-pinene-derived secondary organic aerosol (SOA), bio primary, primarily attributable to fungal spores, bio/urban primary including plant fragments in PM(10) and cooking and traffic emissions in PM(1), biomass burning and combustion fossil to be identified. With mean concentrations up to 2.6 μg Cm(-3), biomass burning dominated the organic fraction in cooler months. Concentrations for α-pinene-derived SOA exceeded isoprene-derived concentrations. Estimated secondary organic carbon contributions to total organic carbon (OC) were between 7% and 42% in PM(10) and between 11% and 60% in PM(1), which is slightly lower than observed for US- or Asian cities. Primary biogenic emissions reached up to 33% of OC in the PM(10)-fraction in the late summer and autumn months. Temperature-dependence was found for both SOA-factors, correlations with ozone and mix depth only for the α-pinene-derived SOA-factor. Latter indicated input of α-pinene from the borders, highlighting differences in the origin of the precursors of both factors. Most factors were regionally distributed. High regional distribution was found to be associated with stronger influence of ambient parameters and higher concentrations at the background station. A significant contribution of biogenic emissions and biomass burning to urban organic aerosol could be stated. This indicates a considerable impact on PM concentrations also in cities in a densely populated area, and should draw the attention concerning health aspects not only to cardio-vascular diseases but also to allergy issues. Copyright © 2012 Elsevier B.V. All rights reserved.

Source apportionments of PM2.5 organic carbon using molecular marker Positive Matrix Factorization and comparison of results from different receptor models

NASA Astrophysics Data System (ADS)

Heo, Jongbae; Dulger, Muaz; Olson, Michael R.; McGinnis, Jerome E.; Shelton, Brandon R.; Matsunaga, Aiko; Sioutas, Constantinos; Schauer, James J.

2013-07-01

Four hundred fine particulate matter (PM2.5) samples collected over a 1-year period at two sites in the Los Angeles Basin were analyzed for organic carbon (OC), elemental carbon (EC), water soluble organic carbon (WSOC) and organic molecular markers. The results were used in a Positive Matrix Factorization (PMF) receptor model to obtain daily, monthly and annual average source contributions to PM2.5 OC. Results of the PMF model showed similar source categories with comparable year-long contributions to PM2.5 OC across the sites. Five source categories providing reasonably stable profiles were identified: mobile, wood smoke, primary biogenic, and two types of secondary organic carbon (SOC) (i.e., anthropogenic and biogenic emissions). Total primary emission factors and total SOC factors contributed approximately 60% and 40%, respectively, to the annual-average OC concentrations. Primary sources showed strong seasonal patterns with high winter peaks and low summer peaks, while SOC showed a reverse pattern with highs in the spring and summer in the region. Interestingly, smoke from forest fires which occurred episodically in California during the summer and fall of 2009 was identified and combined with the primary biogenic source as one distinct factor to the OC budget. The PMF resolved factors were further investigated and compared to a chemical mass balance (CMB) model and a second multi-variant receptor model (UNMIX) using molecular markers considered in the PMF. Good agreement between the source contribution from mobile sources and biomass burning for three models were obtained, providing additional weight of evidence that these source apportionment techniques are sufficiently accurate for policy development. However, the CMB model did not quantify primary biogenic emissions, which were included in other sources with the SOC. Both multivariate receptor models, the PMF and the UNMIX, were unable to separate source contributions from diesel and gasoline engines.

Organic aerosol components derived from 25 AMS datasets across Europe using a newly developed ME-2 based source apportionment strategy

NASA Astrophysics Data System (ADS)

Crippa, M.; Canonaco, F.; Lanz, V. A.; Äijälä, M.; Allan, J. D.; Carbone, S.; Capes, G.; Dall'Osto, M.; Day, D. A.; DeCarlo, P. F.; Di Marco, C. F.; Ehn, M.; Eriksson, A.; Freney, E.; Hildebrandt Ruiz, L.; Hillamo, R.; Jimenez, J.-L.; Junninen, H.; Kiendler-Scharr, A.; Kortelainen, A.-M.; Kulmala, M.; Mensah, A. A.; Mohr, C.; Nemitz, E.; O'Dowd, C.; Ovadnevaite, J.; Pandis, S. N.; Petäjä, T.; Poulain, L.; Saarikoski, S.; Sellegri, K.; Swietlicki, E.; Tiitta, P.; Worsnop, D. R.; Baltensperger, U.; Prévôt, A. S. H.

2013-09-01

Organic aerosols (OA) represent one of the major constituents of submicron particulate matter (PM1) and comprise a huge variety of compounds emitted by different sources. Three intensive measurement field campaigns to investigate the aerosol chemical composition all over Europe were carried out within the framework of EUCAARI and the intensive campaigns of EMEP during 2008 (May-June and September-October) and 2009 (February-March). In this paper we focus on the identification of the main organic aerosol sources and we propose a standardized methodology to perform source apportionment using positive matrix factorization (PMF) with the multilinear engine (ME-2) on Aerodyne aerosol mass spectrometer (AMS) data. Our source apportionment procedure is tested and applied on 25 datasets accounting for urban, rural, remote and high altitude sites and therefore it is likely suitable for the treatment of AMS-related ambient datasets. For most of the sites, four organic components are retrieved, improving significantly previous source apportionment results where only a separation in primary and secondary OA sources was possible. Our solutions include two primary OA sources, i.e. hydrocarbon-like OA (HOA) and biomass burning OA (BBOA) and two secondary OA components, i.e. semi-volatile oxygenated OA (SV-OOA) and low-volatility oxygenated OA (LV-OOA). For specific sites cooking-related (COA) and marine-related sources (MSA) are also separated. Finally, our work provides a large overview of organic aerosol sources in Europe and an interesting set of highly time resolved data for modeling evaluation purposes.

& Source apportionment of particulate matter in the United States and associations with lung inflammatory Markers

EPA Science Inventory

Size-fractionated particulate matter (PM) samples were collected from six U.S. cities and chemically analyzed as part of the Multiple Air Pollutant Study. Particles were administered to cultured lung cells and the production of three different proinflammatory markers was measured...

SOURCE APPORTIONMENT STUDIES OF PM-2.5 IN TWO CZECH CITIES: POSSIBLE USES IN HEALTH STUDIES

EPA Science Inventory

Aerosol and gas phase air pollutant measurements were made in two cities during an ongoing air pollution-health outcome study in the Czech Republic. Teplice, located in northwestern Bohemia, was selected because the local population was exposed to high air pollution levels. Prac...

SOURCE APPORTIONMENT OF PRIMARY CARBONACEOUS AEROSOL USING THE COMMUNITY MULTISCALE AIR QUALITY MODEL

EPA Science Inventory

A substantial fraction of fine particulate matter (PM) across the United States is composed of carbon, which may be either emitted in particulate form (i.e., primary) or formed in the atmosphere through gas-to-particle conversion processes (i.e., secondary). Primary carbonaceous...

Air quality in the German-Czech border region: A focus on harmful fractions of PM and ultrafine particles

NASA Astrophysics Data System (ADS)

Schladitz, Alexander; Leníček, Jan; Beneš, Ivan; Kováč, Martin; Skorkovský, Jiří; Soukup, Aleš; Jandlová, Jana; Poulain, Laurent; Plachá, Helena; Löschau, Gunter; Wiedensohler, Alfred

2015-12-01

A comprehensive air quality study has been carried out at two urban background sites in Annaberg-Buchholz (Germany) and Ústí nad Labem (Czech Republic) in the German-Czech border region between January 2012 and June 2014. Special attention was paid to quantify harmful fractions of particulate matter (PM) and ultrafine particle number concentration (UFP) from solid fuel combustion and vehicular traffic. Source type contributions of UFP were quantified by using the daily concentration courses of UFP and nitrogen oxide. Two different source apportionment techniques were used to quantify relative and absolute mass contributions: positive matrix factorization for total PM2.5 and elemental carbon in PM2.5 and chemical mass balance for total PM1 and organic carbon in PM1. Contributions from solid fuel combustion strongly differed between the non-heating period (April-September) and the heating period (October-March). Major sources of solid fuel combustion in this study were wood and domestic coal combustion, while the proportion of industrial coal combustion was low (<3%). In Ústí nad Labem combustion of domestic brown coal was the most important source of organic carbon ranging from 34% to 43%. Wood combustion was an important source of organic carbon in Annaberg-Buchholz throughout the year. Heavy metals and less volatile polycyclic aromatic hydrocarbons (PAH) in the accumulation mode were related to solid fuel combustion with enhanced concentrations during the heating period. In contrast, vehicular PAH emissions were allocated to the Aitken mode. Only in Ústí nad Labem a significant contribution of photochemical new particle formation (e.g. from sulfur dioxide) to UFP of almost 50% was observed during noontime. UFPs from traffic emissions (nucleation particles) and primary emitted soot particles dominated at both sites during the rest of the day. The methodology of a combined source apportionment of UFP and PM can be adapted to other regions of the world with similar problems of atmospheric pollution to calculate the relative risk in epidemiological health studies for different sub-fractions of PM and UFP. This will enhance the meaningfulness of published relative risks in health studies based on total PM and UFP number concentrations.

PM2.5 Source Apportionment: Reconciling Receptor Models for U.S. Nonurban and Urban Long-Term Networks.

PubMed

Chen, L-W Antony; Watson, John G; Chow, Judith C; DuBois, Dave W; Herschberger, Lisa

2011-11-01

Chemical mass balance (CMB) and trajectory receptor models were applied to speciated particulate matter with aerodynamic diameter ≤2.5 μm (PM 2.5 ) measurements from Speciation Trends Network (STN; part of the Chemical Speciation Network [CSN]) and Interagency Monitoring of Protected Visual Environments (IMPROVE) monitoring network across the state of Minnesota as part of the Minnesota PM 2.5 Source Apportionment Study (MPSAS). CMB equations were solved by the Unmix, positive matrix factorization (PMF), and effective variance (EV) methods, giving collective source contribution and uncertainty estimates. Geological source profiles developed from local dust materials were either incorporated into the EV-CMB model or used to verify factors derived from Unmix and PMF. Common sources include soil dust, calcium (Ca)-rich dust, diesel and gasoline vehicle exhausts, biomass burning, secondary sulfate, and secondary nitrate. Secondary sulfate and nitrate aerosols dominate PM 2.5 mass (50-69%). Mobile sources outweigh area sources at urban sites, and vice versa at rural sites due to traffic emissions. Gasoline and diesel contributions can be separated using data from the STN, despite significant uncertainties. Major differences between MPSAS and earlier studies on similar environments appear to be the type and magnitude of stationary sources, but these sources are generally minor (<7%) in this and other studies. Ensemble back-trajectory analysis shows that the lower Midwestern states are the predominant source region for secondary ammoniated sulfate in Minnesota. It also suggests substantial contributions of biomass burning and soil dust from out-of-state on occasions, although a quantitative separation of local and regional contributions was not achieved in the current study. Supplemental materials are available for this article. Go to the publisher's online edition of the Journal of the Air & Waste Management Association for a summary of input data, Unmix and PMF factor profiles, and additional maps. [Box: see text].

Temporal-spatial characteristics and source apportionment of PM2.5 as well as its associated chemical species in the Beijing-Tianjin-Hebei region of China.

PubMed

Gao, Jiajia; Wang, Kun; Wang, Yong; Liu, Shuhan; Zhu, Chuanyong; Hao, Jiming; Liu, Huanjia; Hua, Shenbing; Tian, Hezhong

2018-02-01

PM 2.5 and its major chemical compositions were sampled and analyzed in January, April, July and October of 2014 at Beijing (BJ), Tianjin (TJ), Langfang (LF) and Baoding (BD) in order to probe the temporal and spatial characteristics as well as source apportionment of PM 2.5 in the Beijing-Tianjin-Hebei (BTH) region. The results showed that PM 2.5 pollution was severe in the BTH region. The average annual concentrations of PM 2.5 at four sampling sites were in the range of 126-180 μg/m 3 , with more than 95% of sampling days exceeding 35 μg/m 3 , the limit ceiling of average annual concentration of PM 2.5 regulated in the Chinese National Ambient Air Quality Standards (GB3095-2012). Additionally, concentrations of PM 2.5 and its major chemical species were seasonally dependent and demonstrated spatially similar variation characteristics in the BTH region. Concentration of toxic heavy metals, such as As, Cd, Cr, Cu, Mn, Ni, Pb, Sb, Se, and Zn, were higher in winter and autumn. Secondary inorganic ions (SO 4 2- , NO 3 - , and NH 4 + ) were the three-major water-soluble inorganic ions (WSIIs) of PM 2.5 and their mass ratios to PM 2.5 were higher in summer and autumn. The organic carbon (OC) and elemental carbon (EC) concentrations were lower in spring and summer than in autumn and winter. Five factors were selected in Positive Matrix Factorization (PMF) model analysis, and the results showed that PM 2.5 pollution was dominated by vehicle emissions in Beijing, combustion emissions including coal burning and biomass combustion in Langfang and Baoding, and soil and construction dust emissions in Tianjin, respectively. The air mass that were derived from the south and southeast local areas around BTH regions reflected the features of short-distant and small-scale air transport. Shandong, Henan, and Hebei were identified the major potential sources-areas of secondary aerosol emissions to PM 2.5 . Copyright © 2017 Elsevier Ltd. All rights reserved.

Source contributions of urban PM2.5 in the Beijing-Tianjin-Hebei region: Changes between 2006 and 2013 and relative impacts of emissions and meteorology

NASA Astrophysics Data System (ADS)

Li, Xin; Zhang, Qiang; Zhang, Yang; Zheng, Bo; Wang, Kai; Chen, Ying; Wallington, Timothy J.; Han, Weijian; Shen, Wei; Zhang, Xiaoye; He, Kebin

2015-12-01

Anthropogenic emissions in China have been controlled for years to improve ambient air quality. However, severe haze events caused by atmospheric aerosols with aerodynamic diameter less than or equal to 2.5 μm (PM2.5) have continued to occur, especially in the Beijing-Tianjin-Hebei (BTH) region. The Chinese government has set an ambitious goal to reduce urban PM2.5 concentrations by 25% in BTH by 2017 relative to the 2012 levels. Source apportionment (SA) is necessary to the development of the effective emission control strategies. In this work, the Comprehensive Air Quality Model with extensions (CAMx) with the Particulate Source Apportionment Technology (PSAT) is applied to the China domain for the years 2006 and 2013. Ambient surface concentrations of PM2.5 and its components are generally well reproduced. To quantify the contributions of each emission category or region to PM2.5 in BTH, the total emissions are divided into 7 emission categories and 11 source regions. The source contributions determined in this work are generally consistent with results from previous work. In 2013, the industrial (44%) and residential (27%) sectors are the dominant contributors to urban PM2.5 in BTH. The residential sector is the largest contributor in winter; the industry sector dominates in other seasons. A slight increasing trend (+3% for industry and +6% for residential) is found in 2013 relative to 2006, necessitating more attention to these two sectors. Local emissions make the largest contribution (40%-60%) for all receptors. Change of source contribution of PM2.5 in Beijing and northern Hebei are dominate by change of local emission. However, for Tianjin, and central and southern Hebei, change of meteorology condition are as important as change of emission, because regional inflow in these areas is more important than in Beijing and northern Hebei and can increase under unfavorable weather conditions, indicating a strong need for regional joint emission control efforts. The results in this study enhance the quantitative understanding of the source-receptor relationships and provide an important basis for policymaking to advance the control of PM2.5 pollution in China.

Source apportionment of PM(2.5) in the harbour-industrial area of Brindisi (Italy): identification and estimation of the contribution of in-port ship emissions.

PubMed

Cesari, D; Genga, A; Ielpo, P; Siciliano, M; Mascolo, G; Grasso, F M; Contini, D

2014-11-01

Harbours are important for economic and social development of coastal areas but they also represent an anthropogenic source of emissions often located near urban centres and industrial areas. This increases the difficulties in distinguishing the harbour contribution with respect to other sources. The aim of this work is the characterisation of main sources of PM2.5 acting on the Brindisi harbour-industrial area, trying to pinpoint the contribution of in-port ship emissions to primary and secondary PM2.5. Brindisi is an important port-city of the Adriatic Sea considered a hot-spot for anthropogenic environmental pressures at National level. Measurements were performed collecting PM2.5 samples and characterising the concentrations of 23 chemical species (water soluble organic and inorganic carbon; major ions: SO4(2-), NO3(-), NH4(+), Cl(-), C2O4(2-), Na(+), K(+), Mg(2+), Ca(2+); and elements: Ni, Cu, V, Mn, As, Pb, Cr, Sb, Fe, Al, Zn, and Ti). These species represent, on average, 51.4% of PM2.5 and were used for source apportionment via PMF. The contributions of eight sources were estimated: crustal (16.4±0.9% of PM2.5), aged marine (2.6±0.5%), crustal carbonates (7.7±0.3%), ammonium sulphate (27.3±0.8%), biomass burning-fires (11.7±0.7%), traffic (16.4±1.7 %), industrial (0.4±0.3%) and a mixed source oil combustion-industrial including ship emissions in harbour (15.3±1.3%). The PMF did not separate the in-port ship emission contribution from industrial releases. The correlation of estimated contribution with meteorology showed directionality with an increase of oil combustion and sulphate contribution in the harbour direction with respect to the direction of the urban area and an increase of the V/Ni ratio. This allowed for the use of V as marker of primary ship contribution to PM2.5 (2.8%+/-1.1%). The secondary contribution of oil combustion to non-sea-salt-sulphate, nssSO4(2-), was estimated to be 1.3 μg/m(3) (about 40% of total nssSO4(2-) or 11% of PM2.5). Copyright © 2014 Elsevier B.V. All rights reserved.

Chemical mass balance (CMB) source apportionment and organic speciation of PM(2.5) in Missoula, Montana including the 2000 wildfire season

NASA Astrophysics Data System (ADS)

Ward, Tony J.

A yearlong sampling program for PM2.5, Semi- Volatile Organic Compounds (SVOCs), and Volatile Organic Compounds (VOCs) was conducted in 2000/2001. The data were used in a Chemical Mass Balance (CMB) Source Apportionment Model (Version 8.0) to apportion the sources of PM2.5 in the Missoula Valley. Results showed that wood combustion contributed an average of 41% to the fine fraction throughout the year. The second largest source of PM 2.5 was diesel (19%), followed by ammonium nitrate (17%), the kraft recovery boilers from Smurfit-Stone Container (14%), other hog fuel boilers (6%), and street sand (5%). Results also showed that PM2.5 levels and contributions from sources were consistent on both sides of the Missoula Valley, but VOCs were twice as high in Missoula compared to Frenchtown. Another aspect of this program was to investigate the organic fraction of the Missoula Valley PM2.5 by evaluating a modified Federal Reference Method (FRM) PM2.5 sampler. A method comparison was also made between sampling for SVOCs using the modified PM2.5 sampler and in using a Hi-volume Polyurethane Foam (PUF) sampler. Results showed that the PM 2.5 PUF measured more of the lighter SVOCs compared to the Hi-vol PUF sampler. This is most likely the result of the higher flows through the Hi-vol PUF which ``strip'' the lighter organics from the surface of the filter. The wildland fires of summer 2000 comprised one of the most severe fire seasons is U.S. history, and had a direct impact on the city of Missoula. Sampling in Missoula was already in progress when the fires began and smoke started rolling into the Missoula Valley. Samples were collected before, during, and after the 2000 fire season, and a detailed characterization of particulate and gaseous emissions from extensive wildland fires was obtained. The 2000/2001 CMB Sampling Program data collected during the 2000 fire season suggest that the main health impacts to downwind populations reside in the fine particulate exposures, with an average of 81% of the Missoula Valley PM2.5 resulting from forest fires.

Spatial and temporal variability of fine particle composition and source types in five cities of Connecticut and Massachusetts.

PubMed

Lee, Hyung Joo; Gent, Janneane F; Leaderer, Brian P; Koutrakis, Petros

2011-05-01

To protect public health from PM(2.5) air pollution, it is critical to identify the source types of PM(2.5) mass and chemical components associated with higher risks of adverse health outcomes. Source apportionment modeling using Positive Matrix Factorization (PMF), was used to identify PM(2.5) source types and quantify the source contributions to PM(2.5) in five cities of Connecticut and Massachusetts. Spatial and temporal variability of PM(2.5) mass, components and source contributions were investigated. PMF analysis identified five source types: regional pollution as traced by sulfur, motor vehicle, road dust, oil combustion and sea salt. The sulfur-related regional pollution and traffic source type were major contributors to PM(2.5). Due to sparse ground-level PM(2.5) monitoring sites, current epidemiological studies are susceptible to exposure measurement errors. The higher correlations in concentrations and source contributions between different locations suggest less spatial variability, resulting in less exposure measurement errors. When concentrations and/or contributions were compared to regional averages, correlations were generally higher than between-site correlations. This suggests that for assigning exposures for health effects studies, using regional average concentrations or contributions from several PM(2.5) monitors is more reliable than using data from the nearest central monitor. Copyright © 2011 Elsevier B.V. All rights reserved.

Mass closure and source apportionment of PM2.5 by Positive Matrix Factorization analysis in urban Mediterranean environment

NASA Astrophysics Data System (ADS)

Mantas, E.; Remoundaki, E.; Halari, I.; Kassomenos, P.; Theodosi, C.; Hatzikioseyian, A.; Mihalopoulos, N.

2014-09-01

A systematic monitoring of PM2.5 was carried out during a period of three years (from February 2010 to April 2013) at an urban site, at the National Technical University of Athens campus. Two types of 24-h PM2.5 samples have been collected: 271 samples on PTFE and 116 samples on quartz filters. Daily PM2.5 concentrations were determined for both types of samples. Total sulfur, crustal origin elements and elements of a major crustal component (Al, Si, Fe, Ca, K, Mg, Ti) trace elements (Zn, Pb, Cu, Ni, P, V, Cr, Mn) and water soluble ions (Cl-, NO3-, SO42-, Na+, K+, NH4+, Ca2+, Mg2+) were determined on the PTFE samples. Organic carbon (OC), elemental carbon (EC) and water soluble ions were determined on the quartz samples. For the mass closure six components were considered: Secondary Inorganic Aerosol (SIA), Organic Matter (OM), Elemental Carbon (EC), Dust, Mineral anthropogenic component (MIN) and Sea Salt (SS). SIA and OM contributed in the mass of PM2.5 almost equally: 30-36% and 30% respectively. EC, SS and MIN accounted for 5, 4 and 3% respectively of the total PM2.5 mass. Dust accounted for about 3-5% in absence of dust transport event and reached a much higher percentage in case of dust transport event. These contributions justify at least 80% of the PM2.5 mass. Source apportionment analysis has been performed by Positive Matrix Factorization. The combination of the PMF results obtained by both data sets lead to the definition of six factors: 1. SO42-, NH4+, OC (industrial/regional sources, secondary aerosol) 2. EC, OC, K and trace metals (traffic and heating by biomass burning, locally emitted aerosol). 3. Ca, EC, OC and trace metals (urban-resuspended road dust reflecting exhaust emissions), 4. Secondary nitrates 5. Na, Cl (marine source) 6. Si, Al, Ti, Ca, Fe (Dust transported from Sahara). These factors reflect not only main sources contributions but also underline the key role of atmospheric dynamics and aerosol ageing processes in this Mediterranean environment.

Characterization and source apportionment of particulate matter < or = 2.5 micrometer in Sumatra, Indonesia, during a recent peat fire episode.

PubMed

See, Siao Wei; Balasubramanian, Rajasekhar; Rianawati, Elisabeth; Karthikeyan, Sathrugnan; Streets, David G

2007-05-15

An intensive field study was conducted in Sumatra, Indonesia, during a peat fire episode to investigate the physical and chemical characteristics of particulate emissions in peat smoke and to provide necessary data for source-receptor analyses. Ambient air sampling was carried out at three different sites located at varying distances from the peatfires to determine changes in mass and number concentrations of PM2.5 and its chemical composition (carbonaceous and nitrogenous materials, polycyclic aromatic hydrocarbons, water-soluble inorganic and organic ions, and total and water-soluble metals). The three sites represent a rural site directly affected by the local peat combustion, a semirural site, and an urban site situated downwind of the peat fires. The mass concentration of PM2.5 and the number concentration of airborne particles were as high as 1600 microg/m3 and 1.7 x 10(5) cm(-3), respectively, in the vicinity of peat fires. The major components of PM2.5 in peat smoke haze were carbonaceous particles, particularly organic carbon, NO3-, and SO4(2-), while the less abundant constituents included ions such as NH4+, NO2-, Na+, K+, organic acids, and metals such as Al, Fe, and Ti. Source apportionment by chemical mass balance receptor modeling indicates that peat smoke can travel long distances and significantly affect the air quality at locations downwind.

Stoichiometry of water-soluble ions in PM2.5: Application in source apportionment for a typical industrial city in semi-arid region, Northwest China

NASA Astrophysics Data System (ADS)

Zhou, Haijun; Lü, Changwei; He, Jiang; Gao, Manshu; Zhao, Boyi; Ren, Limin; Zhang, Lijun; Fan, Qingyun; Liu, Tao; He, Zhongxiang; Dudagula; Zhou, Bin; Liu, Hualin; Zhang, Yu

2018-05-01

Water-soluble ions (WSIs) are major components of PM2.5 and it is valuable for understanding physical and chemical characteristics, sources, behaviors and formation mechanism of WSIs. Baotou is a traditionally industrial city in semi-arid region and frequently subjected to dust storms from March to May. In recent years, air pollution has been listed as one of the most important environmental problems in Baotou. To investigate the seasonal variations and sources of WSIs in PM2.5, the WSIs including SO42-, NO3-, Cl-, F-, NH4+, K+, Na+, Ca2+ and Mg2+ were monitored at six urban sites in Baotou. The results showed that high concentrations of Ca2+ and Na+ were found responding to dust storm events, while high concentrations of SO42-, NO3-, NH4+, K+ and Cl- were observed during haze days. The correlations analysis indicated that excess sulfuric and nitric acid was likely neutralized by carbonate minerals such as calcite, aragonite and dolomite in normal days and cations were fully neutralized during all the sampling periods, while cations were excessive in dust storm days. The concentrations of [NH4+ + SO42- + NO3-], [Na+ + Ca2+ + Mg2+] and [Cl- + K+ + F-] indicated the northwest and southeast region of Baotou presented comparatively high contributions of secondary aerosol and crustal dust, respectively, which were mainly related to the industrial distribution and urbanization process. The cluster analysis, ternary diagram and principal component analysis have a good agreement in source apportionment, where crustal dust sources, secondary aerosol source and the mixture of coal combustion, biomass burning and industrial pollution sources were the main sources of WSIs in PM2.5. The seasonal pattern of sulfur oxidation ratio (SOR) was September > April > November > January, while the nitrogen oxidation ratio (NOR) April > January > November > September in Baotou. This work evaluated the seasonal variation, distribution and source of WSIs on the basis of its stoichiometry in PM2.5, which help to explore the potential sources of these inorganic aerosols and provide scientific suggestion for air quality improvement in Baotou.

Source apportionment of carbonaceous aerosols in a megacity of northwest China: insights from radiocarbon measurement

NASA Astrophysics Data System (ADS)

Ni, Haiyan; Huang, Rujin; Dusek, Ulrike

2017-04-01

Fine particulate matter (PM2.5) samples were collected from 5 July 2008 to 27 June 2009 at Xi'an, a very polluted megacity in Northwest China. The 24 h averaged PM2.5concentrations (ranged from 32 μg m-3 to 339 μg m-3) were 1-14 times higher than the WHO guideline for 24 h PM2.5(25 μg m-3). In this work, we unambiguously quantify fossil (e.g., vehicle emissions, coal burning etc.) and non-fossil (e.g., biomass burning, cooking, biogenic emissions etc.) contributions to organic carbon (OC) and elemental carbon (EC) of PM2.5using radiocarbon (14C) measurement. In addition, we measured PM2.5 major components and source markers, including OC and EC, ions, trace elements, polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (o-PAHs), anhydrous sugars and hopanes. The preliminary results of radiocarbon measurements in OC and EC show that the annual mean contributions from fossil-fuel combustion to EC was 76 ± 8% (6 ± 2 μg m-3). The remaining 24 ± 8% (2 ± 1 μg m-3) was attributed to biomass burning, with higher contribution in the cold period (˜33%) compared to the warm period (˜21%), due to enhanced emissions from local biomass burning activities in winter. In contrast with EC, OC was dominated by non-fossil sources, with an annual average of 54 ± 8 % (13 ± 10 μg m-3). Clear seasonal variations were seen in OC concentrations both from fossil fuel (OCff), and from non-fossil sources (OCnf), with maxima in the cold period and minima in the warm period, because of enhanced fossil and non-fossil activities in winter, mainly biomass burning and domestic coal burning. Further source apportionment of OC, including primary/secondary fossil OC, primary/secondary non-fossil OC, will be conducted by combining 14C results with positive matrix factorization (PMF) analysis of organic matter (OM).

Background PM2.5 source apportionment in the remote Northwestern United States

NASA Astrophysics Data System (ADS)

Hadley, Odelle L.

2017-10-01

This study used the Environmental Protection Agency's positive matrix factorization model (EPA PMF5.0) to identify five primary source factors contributing to the ambient PM2.5 concentrations at Cheeka Peak Atmospheric Observatory (CPO), Neah Bay WA between January 2011 and December 2014. CPO is home to both an IMPROVE (Interagency Monitoring for Protected Visual Environments) and a NCore multi-pollutant monitoring site. Chemically resolved particulate data from the IMPROVE site was the input data to EPA PMF5.0 and the resulting source factors were derived solely from these data. Solutions from the model were analyzed in context with trace gas and meteorological data collected at the NCore site located roughly 10 m away. Seasonal and long-term trends were analyzed for all five factors and provide the first complete source apportionment analysis of PM2.5 at this remote location. The first factor, identified as marine-traffic residual fuel oil (RFO), was the highest contributor to PM2.5 during late summer. Over the 4-year analysis, the RFO percent contribution to total PM2.5 declined. This is consistent with previous studies and may be attributed to regulations restricting the sulfur content of ship fuel. Biomass combustion emissions (BMC) and sea salt were the largest PM2.5 sources observed at CPO in winter, accounting for over 80% of the fine particulate. BMC accounted for a large percent of the fine particulate pollution when winds were easterly, or continental. Sea salt was the dominant winter factor when winds blew from the west. Measured trace carbon monoxide (CO) and reactive nitrogen species (NOy) were most strongly correlated with the BMC factor and continental winds. The fourth factor was identified as aged crustal material, or dust. In all three years, dust peaked in the spring and was associated exclusively with north-easterly winds. The last factor was identified as aged sea salt mixed with nitrate, sulfate, and other components common to RFO and BMC source factors. It did not exhibit a strong seasonal cycle or dependence on wind direction.

SOURCE APPORTIONMENT OF SEATTLE PM 2.5: A COMPARISON OF IMPROVE AND ENHANCED STN DATA SETS

EPA Science Inventory

Seattle, WA, STN and IMPROVE data sets with STN temperature resolved carbon peaks were analyzed with both the PMF and Unmix receptor models. In addition, the IMPROVE trace element data was combined with the major STN species to examine the role of IMPROVE metals. To compare the ...

Anomalous elevated radiocarbon measurements of PM2.5

NASA Astrophysics Data System (ADS)

Buchholz, Bruce A.; Fallon, Stewart J.; Zermeño, Paula; Bench, Graham; Schichtel, Bret A.

2013-01-01

Two-component models are often used to determine the contributions made by fossil fuel and natural sources of carbon in airborne particulate matter (PM). The models reduce thousands of actual sources to two end members based on isotopic signature. Combustion of fossil fuels produces PM free of carbon-14 (14C). Wood or charcoal smoke, restaurant fryer emissions, and natural emissions from plants produce PM with the contemporary concentration of 14C approximately 1.2 × 10-1214C/C. Such data can be used to estimate the relative contributions of fossil fuels and biogenic aerosols to the total aerosol loading and radiocarbon analysis is becoming a popular source apportionment method. Emissions from incinerators combusting medical or biological wastes containing tracer 14C can skew the 14C/C ratio of PM, however, so critical analysis of sampling sites for possible sources of elevated PM needs to be completed prior to embarking on sampling campaigns. Results are presented for two ambient monitoring sites in different areas of the United States where 14C contamination is apparent. Our experience suggests that such contamination is uncommon but is also not rare (∼10%) for PM sampling sites.

Organic aerosol components derived from 25 AMS data sets across Europe using a consistent ME-2 based source apportionment approach

NASA Astrophysics Data System (ADS)

Crippa, M.; Canonaco, F.; Lanz, V. A.; Äijälä, M.; Allan, J. D.; Carbone, S.; Capes, G.; Ceburnis, D.; Dall'Osto, M.; Day, D. A.; DeCarlo, P. F.; Ehn, M.; Eriksson, A.; Freney, E.; Hildebrandt Ruiz, L.; Hillamo, R.; Jimenez, J. L.; Junninen, H.; Kiendler-Scharr, A.; Kortelainen, A.-M.; Kulmala, M.; Laaksonen, A.; Mensah, A. A.; Mohr, C.; Nemitz, E.; O'Dowd, C.; Ovadnevaite, J.; Pandis, S. N.; Petäjä, T.; Poulain, L.; Saarikoski, S.; Sellegri, K.; Swietlicki, E.; Tiitta, P.; Worsnop, D. R.; Baltensperger, U.; Prévôt, A. S. H.

2014-06-01

Organic aerosols (OA) represent one of the major constituents of submicron particulate matter (PM1) and comprise a huge variety of compounds emitted by different sources. Three intensive measurement field campaigns to investigate the aerosol chemical composition all over Europe were carried out within the framework of the European Integrated Project on Aerosol Cloud Climate and Air Quality Interactions (EUCAARI) and the intensive campaigns of European Monitoring and Evaluation Programme (EMEP) during 2008 (May-June and September-October) and 2009 (February-March). In this paper we focus on the identification of the main organic aerosol sources and we define a standardized methodology to perform source apportionment using positive matrix factorization (PMF) with the multilinear engine (ME-2) on Aerodyne aerosol mass spectrometer (AMS) data. Our source apportionment procedure is tested and applied on 25 data sets accounting for two urban, several rural and remote and two high altitude sites; therefore it is likely suitable for the treatment of AMS-related ambient data sets. For most of the sites, four organic components are retrieved, improving significantly previous source apportionment results where only a separation in primary and secondary OA sources was possible. Generally, our solutions include two primary OA sources, i.e. hydrocarbon-like OA (HOA) and biomass burning OA (BBOA) and two secondary OA components, i.e. semi-volatile oxygenated OA (SV-OOA) and low-volatility oxygenated OA (LV-OOA). For specific sites cooking-related (COA) and marine-related sources (MSA) are also separated. Finally, our work provides a large overview of organic aerosol sources in Europe and an interesting set of highly time resolved data for modeling purposes.

Source apportionment of indoor, outdoor and personal PM2.5 exposure of pregnant women in Barcelona, Spain

NASA Astrophysics Data System (ADS)

Minguillón, M. C.; Schembari, A.; Triguero-Mas, M.; de Nazelle, A.; Dadvand, P.; Figueras, F.; Salvado, J. A.; Grimalt, J. O.; Nieuwenhuijsen, M.; Querol, X.

2012-11-01

Exposure to air pollution has been shown to adversely affect foetal development in the case of pregnant women. The present study aims to investigate the PM composition and sources influencing personal exposure of pregnant women in Barcelona. To this end, indoor, outdoor and personal exposure measurements were carried out for a selection of 54 pregnant women between November 2008 and November 2009. PM2.5 samples were collected during two consecutive days and then analysed for black smoke (BS), major and trace elements, and polycyclic aromatic hydrocarbons (PAHs) concentrations. Personal information such as commuting patterns and cosmetics use was also collected. PM2.5 concentrations were higher for personal samples than for indoor and outdoor environments. Indoor, outdoor and personal BS and sulphate concentrations were strongly correlated, although some specific indoor and outdoor sulphate sources may exist. Average trace elements concentrations were similar indoor, outdoor and for personal exposure, but the correlations were moderate for most of them. Most of the PAHs concentrations showed strong correlations indoor-outdoor. A source apportionment analysis of the PM composition data by means of a Positive Matrix Factorization (PMF) resulted in the identification of six sources for the outdoor and indoor environments: secondary sulphate, fueloil + sea salt (characterized by V, Ni, Na and Mg), mineral, cigarette (characterized by K, Ce, Cd, benzo(k)fluoranthene and benzo(ghi)perylene), road traffic (characterized by BS and low weight PAHs), and industrial (characterized by Pb, Sn, Cu, Mn and Fe). For personal exposure two specific sources were found: cosmetics (characterized by abundance of Ca, Li, Ti and Sr and the absence of Al) and train/subway (characterized by Fe, Mn, Cu and Ba). The contribution of the sources varied widely among women, especially for cigarette (from zero to up to 4 μg m-3), train/subway (up to more than 6 μg m-3) and cosmetics (up to more than 5 μg m-3). The source contributions showed generally strong correlations indoor-outdoor although the infiltration efficiencies varied among homes. This study emphasizes the importance of relying on personal exposure in epidemiological studies assessing the impact of air pollution on human health.

Source apportionment of PAHs and n-alkanes bound to PM1 collected near the Venice highway.

PubMed

Valotto, Gabrio; Rampazzo, Giancarlo; Gonella, Francesco; Formenton, Gianni; Ficotto, Silvia; Giraldo, Giorgia

2017-04-01

n-Alkanes and polycyclic aromatic hydrocarbons (PAHs) bound to atmospheric particulate matter (PM 1 ) were investigated in a traffic site located in an urban area of Venice Province (Eastern Po Valley, Italy) during the cold season. Considering the critical situation affecting the Veneto Region concerning the atmospheric pollution and the general lack of information on PM 1 composition and emission in this area, this experimental study aims at determining the source profile, their relative contributions and the dispersion of finer particles. Four sources were identified and quantified using the Positive Matrix Factorization receptor model: (1) mixed combustions related to the residential activities, (2) agricultural biomass burning in addition to the resuspension of anthropogenic and natural debris carried by the wind, (3) gasoline and (4) diesel traffic-related combustions. The role of local atmospheric circulation was also investigated to identify the pollutant sources. Copyright © 2016. Published by Elsevier B.V.

Indoor source apportionment in urban communities near industrial sites

NASA Astrophysics Data System (ADS)

Tunno, Brett J.; Dalton, Rebecca; Cambal, Leah; Holguin, Fernando; Lioy, Paul; Clougherty, Jane E.

2016-08-01

Because fine particulate matter (PM2.5) differs in chemical composition, source apportionment is frequently used for identification of relative contributions of multiple sources to outdoor concentrations. Indoor air pollution and source apportionment is often overlooked, though people in northern climates may spend up to 90% of their time inside. We selected 21 homes for a 1-week indoor sampling session during summer (July to September 2011), repeated in winter (January to March 2012). Elemental analysis was performed using inductively-coupled plasma mass spectrometry (ICP-MS), and factor analysis was used to determine constituent grouping. Multivariate modeling was run on factor scores to corroborate interpretations of source factors based on a literature review. For each season, a 5-factor solution explained 86-88% of variability in constituent concentrations. Indoor sources (i.e. cooking, smoking) explained greater variability than did outdoor sources in these industrial communities. A smoking factor was identified in each season, predicted by number of cigarettes smoked. Cooking factors were also identified in each season, explained by frequency of stove cooking and stovetop frying. Significant contributions from outdoor sources including coal and motor vehicles were also identified. Higher coal and secondary-related elemental concentrations were detected during summer than winter. Our findings suggest that source contributions to indoor concentrations can be identified and should be examined in relation to health effects.

Urban particulate matter pollution: a tale of five cities.

PubMed

Pandis, Spyros N; Skyllakou, Ksakousti; Florou, Kalliopi; Kostenidou, Evangelia; Kaltsonoudis, Christos; Hasa, Erion; Presto, Albert A

2016-07-18

Five case studies (Athens and Paris in Europe, Pittsburgh and Los Angeles in the United States, and Mexico City in Central America) are used to gain insights into the changing levels, sources, and role of atmospheric chemical processes in air quality in large urban areas as they develop technologically. Fine particulate matter is the focus of our analysis. In all cases reductions of emissions by industrial and transportation sources have resulted in significant improvements in air quality during the last few decades. However, these changes have resulted in the increasing importance of secondary particulate matter (PM) which dominates over primary in most cases. At the same time, long range transport of secondary PM from sources located hundreds of kilometres from the cities is becoming a bigger contributor to the urban PM levels in all seasons. "Non-traditional" sources including cooking, and residential and agricultural biomass burning contribute an increasing fraction of the now reduced fine PM levels. Atmospheric chemistry is found to change the chemical signatures of a number of these sources relatively fast both during the day and night, complicating the corresponding source apportionment.

Source apportionment of visual impairment during the California regional PM 10/PM 2.5 air quality study

NASA Astrophysics Data System (ADS)

Chen, Jianjun; Ying, Qi; Kleeman, Michael J.

2009-12-01

Gases and particulate matter predictions from the UCD/CIT air quality model were used in a visibility model to predict source contributions to visual impairment in the San Joaquin Valley (SJV), the southern portion of California's Central Valley, during December 2000 and January 2001. Within the SJV, daytime (0800-1700 PST) light extinction was dominated by scattering associated with airborne particles. Measured daytime particle scattering coefficients were compared to predicted values at approximately 40 locations across the SJV after correction for the increased temperature and decreased relative humidity produced by "smart heaters" placed upstream of nephelometers. Mean fractional bias and mean fractional error were -0.22 and 0.65, respectively, indicating reasonable agreement between model predictions and measurements. Particulate water, nitrate, organic matter, and ammonium were the major particulate species contributing to light scattering in the SJV. Daytime light extinction in the SJV averaged between December 25, 2000 and January 7, 2001 was mainly associated with animal ammonia sources (28%), diesel engines (18%), catalyst gasoline engines (9%), other anthropogenic sources (9%), and wood smoke (7%) with initial and boundary conditions accounting for 13%. The source apportionment results from this study apply to wintertime conditions when airborne particulate matter concentrations are typically at their annual maximum. Further study would be required to quantify source contributions to light extinction in other seasons.

Inter-comparison of source apportionment of PM10 using PMF and CMB in three sites nearby an industrial area in central Italy

NASA Astrophysics Data System (ADS)

Cesari, Daniela; Donateo, Antonio; Conte, Marianna; Contini, Daniele

2016-12-01

Receptor models (RMs), based on chemical composition of particulate matter (PM), such as Chemical Mass Balance (CMB) and Positive Matrix Factorization (PMF), represent useful tools for determining the impact of PM sources to air quality. This information is useful, especially in areas influenced by anthropogenic activities, to plan mitigation strategies for environmental management. Recent inter-comparison of source apportionment (SA) results showed that one of the difficulties in the comparison of estimated source contributions is the compatibility of the sources, i.e. the chemical profiles of factor/sources used in receptor models. This suggests that SA based on integration of several RMs could give more stable and reliable solutions with respect to a single model. The aim of this work was to perform inter-comparison of PMF (using PMF3.0 and PMF5.0 codes) and CMB outputs, focusing on both source chemical profiles and estimates of source contributions. The dataset included 347 daily PM10 samples collected in three sites in central Italy located near industrial emissions. Samples were chemically analysed for the concentrations of 21 chemical species (NH4+, Ca2 +, Mg2 +, Na+, K+, Mg2 +, SO42 -, NO3-, Cl-, Si, Al, Ti, V, Mn, Fe, Ni, Cu, Zn, Br, EC, and OC) used as input of RMs. The approach identified 9 factor/sources: marine, traffic, resuspended dust, biomass burning, secondary sulphate, secondary nitrate, crustal, coal combustion power plant and harbour-industrial. Results showed that the application of constraints in PMF5.0 improved interpretability of profiles and comparability of estimated source contributions with stoichiometric calculations. The inter-comparison of PMF and CMB gave significant differences for secondary nitrate, biomass burning, and harbour-industrial sources, due to non-compatibility of these source profiles that have local specificities. When these site-dependent specificities were taken into account, optimising the input source profiles of CMB, a significant improvement in the comparison of the estimated source contributions with PMF was obtained.

[Size distributions and source apportionment of soluble ions in aerosol in Nanjing].

PubMed

Xue, Guo-Qiang; Zhu, Bin; Wang, Hong-Lei

2014-05-01

To explore the seasonal variation and source apportionment of soluble ions in PM10, PM2.1 and PM1.1, the aerosol mass. concentration and soluble ion concentration were investigated during a one-year observation in the urban-district and north suburb. As the results showed, (1)The concentrations of PM10, PM2.1, PM1.1 were in the order of winter > spring > autumn > summer. In spring, summer and autumn, the concentrations of PM10, PM2.1, PM1.1 in the north suburb were higher than in the urban, while the situation, was opposite in winter. (2) SO(2-)(4), NO(-)(3), Ca2+, NH(+)(4), Cl-, K+, Na+, F-, NO;, Mg2+ were measured, and their total concentration in PM10 was 46 microg.m -3 in urban sites and 39.6 microg m in north suburbs. Mass fraction percentage o f water soluble ion in PM2.1-10, PM1 1-2.1, PM1.1 in the urban district increased from 20.4% to 49.5% and 56% , and the value in the north suburb increased from 18.3% to 37. 9% and 42.5%. (3) Major ions, SO(2-)(4), NO(-)(3) , NH(+)(4) , second components and Ca2+ , had significant seasonal variation. In the urban district, the highest concentrations were observed in winter, and the lowest in summer, while in the. north suburb, the highest concentrations were observed in spring, and the lowest in summer. The seasonal changing climate in Nanjing and different anthropogenic influences with land surface in urban-suburb may be the major factors for the ions' seasonal variation. (4) NH(+)(4) , SO(2-)(4) , NO(-)(3) came from secondary chemical reactions of NH3, SO2, NO,, and these precursors mostly came from automobile exhaust in Summer while equally came from automobile exhaust and fossil fuel in winter. Cl- came from biomass burning in Winter . while transported from sea salt with Na+ in Summer. Ca2+ and Mg2+ came from ground dust and construction dust. K+, F- , NO(-)(2) may come from biomass burning and industrial emissions.

Polycyclic Aromatic Hydrocarbons Bound to PM 2.5 in Urban Coimbatore, India with Emphasis on Source Apportionment

PubMed Central

Mohanraj, R.; Dhanakumar, S.; Solaraj, G.

2012-01-01

Coimbatore is one of the fast growing industrial cities of Southern India with an urban population of 1.9 million. This study attempts to evaluate the trends of airborne fine particulates (PM 2.5) and polyaromatic hydrocarbons (PAH) on them. The PM 2.5 mass was collected in polytetra fluoroethylene filters using fine particulate sampler at monthly intervals during March 2009 to February 2010. PAHs were extracted from PM 2.5 and estimated by high-performance liquid chromatography. It is alarming to note that PM 2.5 values ranged between 27.85 and 165.75 μg/m3 and exceeded the air quality standards in many sampling events. The sum of 9 PAHs bound to PM 2.5 in a single sampling event ranged from 4.1 to 1632.3 ng/m3. PAH diagnostic ratios and principal component analysis results revealed vehicular emissions and diesel-powered generators as predominant sources of PAH in Coimbatore. PMID:22649329

The Use of Principal Component Analysis for Source Identification of PM2.5 from Selected Urban and Regional Background Sites in Poland

NASA Astrophysics Data System (ADS)

Błaszczak, Barbara

2018-01-01

The paper reports the results of the measurements of water-soluble ions and carbonaceous matter content in the fine particulate matter (PM2.5), as well as the contributions of major sources in PM2.5. Daily PM2.5 samples were collected during heating and non-heating season of the year 2013 in three different locations in Poland: Szczecin (urban background), Trzebinia (urban background) and Złoty Potok (regional background). The concentrations of PM2.5, and its related components, exhibited clear spatiotemporal variability with higher levels during the heating period. The share of the total carbon (TC) in PM2.5 exceeded 40% and was primarily determined by fluctuations in the share of OC. Sulfates (SO42-), nitrates (NO3-) and ammonium (NH4+) dominated in the ionic composition of PM2.5 and accounted together 34% (Szczecin), 30% (Trzebinia) and 18% (Złoty Potok) of PM2.5 mass. Source apportionment analysis, performed by PCA-MLRA model (Principal Component Analysis - Multilinear Regression Analysis), revealed that secondary aerosol, whose presence is related to oxidation of gaseous precursors emitted from fuel combustion and biomass burning, had the largest contribution in observed PM2.5 concentrations. In addition, the contribution of traffic sources together with road dust resuspension, was observed. The share of natural sources (sea spray, crustal dust) was generally lower.

Characterizing and sourcing ambient PM2.5 over key emission regions in China III: Carbon isotope based source apportionment of black carbon

NASA Astrophysics Data System (ADS)

Yu, Kuangyou; Xing, Zhenyu; Huang, Xiaofeng; Deng, Junjun; Andersson, August; Fang, Wenzheng; Gustafsson, Örjan; Zhou, Jiabin; Du, Ke

2018-03-01

Regional haze over China has severe implications for air quality and regional climate. To effectively combat these effects the high uncertainties regarding the emissions from different sources needs to be reduced. In this paper, which is the third in a series on the sources of PM2.5 in pollution hotspot regions of China, we focus on the sources of black carbon aerosols (BC), using carbon isotope signatures. Four-season samples were collected at two key locations: Beijing-Tianjin-Hebei (BTH, part of Northern China plain), and the Pearl River Delta (PRD). We find that that fossil fuel combustion was the predominant source of BC in both BTH and PRD regions, accounting for 75 ± 5%. However, the contributions of what fossil fuel components were dominating differed significantly between BTH and PRD, and varied dramatically with seasons. Coal combustion is overall the all-important BC source in BTH, accounting for 46 ± 12% of the BC in BTH, with the maximum value (62%) found in winter. In contrast for the PRD region, liquid fossil fuel combustion (e.g., oil, diesel, and gasoline) is the dominant source of BC, with an annual mean value of 41 ± 15% and the maximum value of 55% found in winter. Region- and season-specific source apportionments are recommended to both accurately assess the climate impact of carbonaceous aerosol emissions and to effectively mitigate deteriorating air quality caused by carbonaceous aerosols.

Source apportionment of ambient PM10 and PM2.5 in Haikou, China

NASA Astrophysics Data System (ADS)

Fang, Xiaozhen; Bi, Xiaohui; Xu, Hong; Wu, Jianhui; Zhang, Yufen; Feng, Yinchang

2017-07-01

In order to identify the sources of PM10 and PM2.5 in Haikou, 60 ambient air samples were collected in winter and spring, respectively. Fifteen elements (Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Pb), water-soluble ions (SO42 - and NO3-), and organic carbon (OC) and elemental carbon (EC) were analyzed. It was clear that the concentration of particulate matter was higher in winter than in spring. The value of PM2.5/PM10 was > 0.6. Moreover, the proportions of TC, ions, Na, Al, Si and Ca were more high in PM10 and PM2.5. The SOC concentration was estimated by the minimum OC/EC ratio method, and deducted from particulate matter compositions when running CMB model. According to the results of CMB model, the resuspended dust (17.5-35.0%), vehicle exhaust (14.9-23.6%) and secondary particulates (20.4-28.8%) were the major source categories of ambient particulate matter. Additionally, sea salt also had partial contribution (3-8%). And back trajectory analysis results showed that particulate matter was greatly affected by regional sources in winter, while less affected in spring. So particulate matter was not only affected by local sources, but also affected by sea salt and regional sources in coastal cities. Further research could focuses on establishing the actual secondary particles profiles and identifying the local and regional sources of PM at once by one model or analysis method.

Implementation and evaluation of PM2.5 source contribution ...

EPA Pesticide Factsheets

Source culpability assessments are useful for developing effective emissions control programs. The Integrated Source Apportionment Method (ISAM) has been implemented in the Community Multiscale Air Quality (CMAQ) model to track contributions from source groups and regions to ambient levels and deposited amounts of primary and secondary inorganic PM2.5. Confidence in this approach is established by comparing ISAM source contribution estimates to emissions zero-out simulations recognizing that these approaches are not always expected to provide the same answer. The comparisons are expected to be most similar for more linear processes such as those involving primary emissions of PM2.5 and most different for non-linear systems like ammonium nitrate formation. Primarily emitted PM2.5 (e.g. elemental carbon), sulfur dioxide, ammonia, and nitrogen oxide contribution estimates compare well to zero-out estimates for ambient concentration and deposition. PM2.5 sulfate ion relationships are strong, but nonlinearity is evident and shown to be related to aqueous phase oxidation reactions in the host model. ISAM and zero-out contribution estimates are less strongly related for PM2.5 ammonium nitrate, resulting from instances of non-linear chemistry and negative responses (increases in PM2.5 due to decreases in emissions). ISAM is demonstrated in the context of an annual simulation tracking well characterized emissions source sectors and boundary conditions shows source contri

Differences Between Magnitudes and Health Impacts of BC Emissions Across the United States Using 12 km Scale Seasonal Source Apportionment

EPA Science Inventory

Recent assessments have analyzed the health impacts of PM2.5 from emissions from different locations and sectors using simplified or reduced-form air quality models. Here we present an alternative approach using the adjoint of the Community Multiscale Air Quality (CMAQ) model, wh...

Major tire fragment contributions to PM{sub 10} non-attainment in Anchorage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Draftz, R.G.; Cowherd, C. Jr.; Grelinger, M.A.

1999-07-01

Anchorage exceeded the 24-hour National Ambient Air Quality Standard for PM{sub 10} a total of thirty-one times in the period from 1987 to 1997. About half of these exceedances were due to natural events. The remaining exceedances could not be linked to natural events. Moreover, these exceedances occurred predominantly at one PM{sub 10} site near one of the major thoroughfares in Anchorage. The apportionment of sources producing these unexplained violations was one of the major goals of a 1996--98 study sponsored and directed by the Air Quality Program of the Municipality of Anchorage. Two suites of PM{sub 10} samples weremore » utilized for source apportionment of exceedances. The first consisted of historical samples selected from sampling periods unaffected by natural events. These samples were carefully selected to avoid the high values during and following volcanic eruptions when there were likely to be considerable accumulations of volcanic ejecta on roads. Dust storms were excluded by simple inspection of data for days that showed that all sites in the Anchorage basin had high PM{sub 10} loadings. The second group of samples were selected from a special springtime road dust tagging experiment used to measure emission and depletion rates of the taggant and accumulated road dust particles, mainly road aggregate wear and anti-skid minerals. Quantitative microscopical analysis of the first suite of historical samples showed that rubber tire concentrations contributed from approximately 12 to 42{micro}g/m{sup 3} of the PM{sub 10} for samples near or exceeding the 24 hour limit. Road dust samples from the road tagging experiment showed that the PM{sub 10}-sized tire fragments were not present in the road dust and therefore, had to have become immediately airborne rather than re-entrained from road dust deposits. Rubber tire fragments are one of the three dominant components that collectively account for more than 95% of the PM{sub 10} non-attainment in Anchorage.« less

Constrained positive matrix factorization: Elemental ratios, spatial distinction, and chemical transport model source contributions

NASA Astrophysics Data System (ADS)

Sturtz, Timothy M.

Source apportionment models attempt to untangle the relationship between pollution sources and the impacts at downwind receptors. Two frameworks of source apportionment models exist: source-oriented and receptor-oriented. Source based apportionment models use presumed emissions and atmospheric processes to estimate the downwind source contributions. Conversely, receptor based models leverage speciated concentration data from downwind receptors and apply statistical methods to predict source contributions. Integration of both source-oriented and receptor-oriented models could lead to a better understanding of the implications sources have on the environment and society. The research presented here investigated three different types of constraints applied to the Positive Matrix Factorization (PMF) receptor model within the framework of the Multilinear Engine (ME-2): element ratio constraints, spatial separation constraints, and chemical transport model (CTM) source attribution constraints. PM10-2.5 mass and trace element concentrations were measured in Winston-Salem, Chicago, and St. Paul at up to 60 sites per city during two different seasons in 2010. PMF was used to explore the underlying sources of variability. Information on previously reported PM10-2.5 tire and brake wear profiles were used to constrain these features in PMF by prior specification of selected species ratios. We also modified PMF to allow for combining the measurements from all three cities into a single model while preserving city-specific soil features. Relatively minor differences were observed between model predictions with and without the prior ratio constraints, increasing confidence in our ability to identify separate brake wear and tire wear features. Using separate data, source contributions to total fine particle carbon predicted by a CTM were incorporated into the PMF receptor model to form a receptor-oriented hybrid model. The level of influence of the CTM versus traditional PMF was varied using a weighting parameter applied to an object function as implemented in ME-2. The resulting hybrid model was used to quantify the contributions of total carbon from both wildfires and biogenic sources at two Interagency Monitoring of Protected Visual Environment monitoring sites, Monture and Sula Peak, Montana, from 2006 through 2008.

Source apportionment of fine particles and its chemical components over the Yangtze River Delta, China during a heavy haze pollution episode

NASA Astrophysics Data System (ADS)

Li, L.; An, J. Y.; Zhou, M.; Yan, R. S.; Huang, C.; Lu, Q.; Lin, L.; Wang, Y. J.; Tao, S. K.; Qiao, L. P.; Zhu, S. H.; Chen, C. H.

2015-12-01

An extremely high PM2.5 pollution episode occurred over the eastern China in January 2013. In this paper, the particulate matter source apportionment technology (PSAT) method coupled within the Comprehensive air quality model with extensions (CAMx) is applied to study the source contributions to PM2.5 and its major components at six receptors (Urban Shanghai, Chongming, Dianshan Lake, Urban Suzhou, Hangzhou and Zhoushan) in the Yangtze River Delta (YRD) region. Contributions from 4 source areas (including Shanghai, South Jiangsu, North Zhejiang and Super-region) and 9 emission sectors (including power plants, industrial boilers and kilns, industrial processing, mobile source, residential, volatile emissions, dust, agriculture and biogenic emissions) to PM2.5 and its major components (sulfate, nitrate, ammonia, organic carbon and elemental carbon) at the six receptors in the YRD region are quantified. Results show that accumulation of local pollution was the largest contributor during this air pollution episode in urban Shanghai (55%) and Suzhou (46%), followed by long-range transport (37% contribution to Shanghai and 44% to Suzhou). Super-regional emissions play an important role in PM2.5 formation at Hangzhou (48%) and Zhoushan site (68%). Among the emission sectors contributing to the high pollution episode, the major source categories include industrial processing (with contributions ranging between 12.7 and 38.7% at different receptors), combustion source (21.7-37.3%), mobile source (7.5-17.7%) and fugitive dust (8.4-27.3%). Agricultural contribution is also very significant at Zhoushan site (24.5%). In terms of the PM2.5 major components, it is found that industrial boilers and kilns are the major source contributor to sulfate and nitrate. Volatile emission source and agriculture are the major contributors to ammonia; transport is the largest contributor to elemental carbon. Industrial processing, volatile emissions and mobile source are the most significant contributors to organic carbon. Results show that the Yangtze River Delta region should focus on the joint pollution control of industrial processing, combustion emissions, mobile source emissions, and fugitive dust. Regional transport of air pollution among the cities are prominent, and the implementation of regional joint prevention and control of air pollution will help to alleviate fine particulate matter concentrations under heavy pollution case significantly.

The effects of particulate matter sources on daily mortality: a case-crossover study of Barcelona, Spain.

PubMed

Ostro, Bart; Tobias, Aurelio; Querol, Xavier; Alastuey, Andrés; Amato, Fulvio; Pey, Jorge; Pérez, Noemí; Sunyer, Jordi

2011-12-01

Dozens of studies link acute exposure to particulate matter (PM) air pollution with premature mortality and morbidity, but questions remain about which species and sources in the vast PM mixture are responsible for the observed health effects. Although a few studies exist on the effects of species and sources in U.S. cities, European cities-which have a higher proportion of diesel engines and denser urban populations-have not been well characterized. Information on the effects of specific sources could aid in targeting pollution control and in articulating the biological mechanisms of PM. Our study examined the effects of various PM sources on daily mortality for 2003 through 2007 in Barcelona, a densely populated city in the northeast corner of Spain. Source apportionment for PM ≤ 2.5 μm and ≤ 10 µm in aerodynamic diameter (PM2.5 and PM10) using positive matrix factorization identified eight different factors. Case-crossover regression analysis was used to estimate the effects of each factor. Several sources of PM2.5, including vehicle exhaust, fuel oil combustion, secondary nitrate/organics, minerals, secondary sulfate/organics, and road dust, had statistically significant associations (p < 0.05) with all-cause and cardiovascular mortality. Also, in some cases relative risks for a respective interquartile range increase in concentration were higher for specific sources than for total PM2.5 mass. These results along with those from our multisource models suggest that traffic, sulfate from shipping and long-range transport, and construction dust are important contributors to the adverse health effects linked to PM.

Advanced source apportionment of size-resolved trace elements at multiple sites in London during winter

DOE PAGES

Visser, S.; Slowik, Jay G.; Furger, M.; ...

2015-10-12

Here, trace element measurements in PM 10–2.5, PM 2.5–1.0 and PM 1.0–0.3 aerosol were performed with 2 h time resolution at kerbside, urban background and rural sites during the ClearfLo winter 2012 campaign in London. The environment-dependent variability of emissions was characterized using the Multilinear Engine implementation of the positive matrix factorization model, conducted on data sets comprising all three sites but segregated by size. Combining the sites enabled separation of sources with high temporal covariance but significant spatial variability. Separation of sizes improved source resolution by preventing sources occurring in only a single size fraction from having too smallmore » a contribution for the model to resolve. Anchor profiles were retrieved internally by analysing data subsets, and these profiles were used in the analyses of the complete data sets of all sites for enhanced source apportionment. A total of nine different factors were resolved (notable elements in brackets): in PM 10–2.5, brake wear (Cu, Zr, Sb, Ba), other traffic-related (Fe), resuspended dust (Si, Ca), sea/road salt (Cl), aged sea salt (Na, Mg) and industrial (Cr, Ni); in PM 2.5–1.0, brake wear, other traffic-related, resuspended dust, sea/road salt, aged sea salt and S-rich (S); and in PM 1.0–0.3, traffic-related (Fe, Cu, Zr, Sb, Ba), resuspended dust, sea/road salt, aged sea salt, reacted Cl (Cl), S-rich and solid fuel (K, Pb). Human activities enhance the kerb-to-rural concentration gradients of coarse aged sea salt, typically considered to have a natural source, by 1.7–2.2. These site-dependent concentration differences reflect the effect of local resuspension processes in London. The anthropogenically influenced factors traffic (brake wear and other traffic-related processes), dust and sea/road salt provide further kerb-to-rural concentration enhancements by direct source emissions by a factor of 3.5–12.7. The traffic and dust factors are mainly emitted in PM 10–2.5 and show strong diurnal variations with concentrations up to 4 times higher during rush hour than during night-time. Regionally influenced S-rich and solid fuel factors, occurring primarily in PM 1.0–0.3, have negligible resuspension influences, and concentrations are similar throughout the day and across the regions.« less

Advanced source apportionment of size-resolved trace elements at multiple sites in London during winter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Visser, S.; Slowik, Jay G.; Furger, M.

Here, trace element measurements in PM 10–2.5, PM 2.5–1.0 and PM 1.0–0.3 aerosol were performed with 2 h time resolution at kerbside, urban background and rural sites during the ClearfLo winter 2012 campaign in London. The environment-dependent variability of emissions was characterized using the Multilinear Engine implementation of the positive matrix factorization model, conducted on data sets comprising all three sites but segregated by size. Combining the sites enabled separation of sources with high temporal covariance but significant spatial variability. Separation of sizes improved source resolution by preventing sources occurring in only a single size fraction from having too smallmore » a contribution for the model to resolve. Anchor profiles were retrieved internally by analysing data subsets, and these profiles were used in the analyses of the complete data sets of all sites for enhanced source apportionment. A total of nine different factors were resolved (notable elements in brackets): in PM 10–2.5, brake wear (Cu, Zr, Sb, Ba), other traffic-related (Fe), resuspended dust (Si, Ca), sea/road salt (Cl), aged sea salt (Na, Mg) and industrial (Cr, Ni); in PM 2.5–1.0, brake wear, other traffic-related, resuspended dust, sea/road salt, aged sea salt and S-rich (S); and in PM 1.0–0.3, traffic-related (Fe, Cu, Zr, Sb, Ba), resuspended dust, sea/road salt, aged sea salt, reacted Cl (Cl), S-rich and solid fuel (K, Pb). Human activities enhance the kerb-to-rural concentration gradients of coarse aged sea salt, typically considered to have a natural source, by 1.7–2.2. These site-dependent concentration differences reflect the effect of local resuspension processes in London. The anthropogenically influenced factors traffic (brake wear and other traffic-related processes), dust and sea/road salt provide further kerb-to-rural concentration enhancements by direct source emissions by a factor of 3.5–12.7. The traffic and dust factors are mainly emitted in PM 10–2.5 and show strong diurnal variations with concentrations up to 4 times higher during rush hour than during night-time. Regionally influenced S-rich and solid fuel factors, occurring primarily in PM 1.0–0.3, have negligible resuspension influences, and concentrations are similar throughout the day and across the regions.« less

Source Apportionment and Influencing Factor Analysis of Residential Indoor PM2.5 in Beijing

PubMed Central

Yang, Yibing; Liu, Liu; Xu, Chunyu; Li, Na; Liu, Zhe; Wang, Qin; Xu, Dongqun

2018-01-01

In order to identify the sources of indoor PM2.5 and to check which factors influence the concentration of indoor PM2.5 and chemical elements, indoor concentrations of PM2.5 and its related elements in residential houses in Beijing were explored. Indoor and outdoor PM2.5 samples that were monitored continuously for one week were collected. Indoor and outdoor concentrations of PM2.5 and 15 elements (Al, As, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Pb, Se, Tl, V, Zn) were calculated and compared. The median indoor concentration of PM2.5 was 57.64 μg/m3. For elements in indoor PM2.5, Cd and As may be sensitive to indoor smoking, Zn, Ca and Al may be related to indoor sources other than smoking, Pb, V and Se may mainly come from outdoor. Five factors were extracted for indoor PM2.5 by factor analysis, explained 76.8% of total variance, outdoor sources contributed more than indoor sources. Multiple linear regression analysis for indoor PM2.5, Cd and Pb was performed. Indoor PM2.5 was influenced by factors including outdoor PM2.5, smoking during sampling, outdoor temperature and time of air conditioner use. Indoor Cd was affected by factors including smoking during sampling, outdoor Cd and building age. Indoor Pb concentration was associated with factors including outdoor Pb and time of window open per day, building age and RH. In conclusion, indoor PM2.5 mainly comes from outdoor sources, and the contributions of indoor sources also cannot be ignored. Factors associated indoor and outdoor air exchange can influence the concentrations of indoor PM2.5 and its constituents. PMID:29621164

Source Apportionment and Influencing Factor Analysis of Residential Indoor PM2.5 in Beijing.

PubMed

Yang, Yibing; Liu, Liu; Xu, Chunyu; Li, Na; Liu, Zhe; Wang, Qin; Xu, Dongqun

2018-04-05

In order to identify the sources of indoor PM 2.5 and to check which factors influence the concentration of indoor PM 2.5 and chemical elements, indoor concentrations of PM 2.5 and its related elements in residential houses in Beijing were explored. Indoor and outdoor PM 2.5 samples that were monitored continuously for one week were collected. Indoor and outdoor concentrations of PM 2.5 and 15 elements (Al, As, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Pb, Se, Tl, V, Zn) were calculated and compared. The median indoor concentration of PM 2.5 was 57.64 μg/m³. For elements in indoor PM 2.5 , Cd and As may be sensitive to indoor smoking, Zn, Ca and Al may be related to indoor sources other than smoking, Pb, V and Se may mainly come from outdoor. Five factors were extracted for indoor PM 2.5 by factor analysis, explained 76.8% of total variance, outdoor sources contributed more than indoor sources. Multiple linear regression analysis for indoor PM 2.5 , Cd and Pb was performed. Indoor PM 2.5 was influenced by factors including outdoor PM 2.5 , smoking during sampling, outdoor temperature and time of air conditioner use. Indoor Cd was affected by factors including smoking during sampling, outdoor Cd and building age. Indoor Pb concentration was associated with factors including outdoor Pb and time of window open per day, building age and RH. In conclusion, indoor PM 2.5 mainly comes from outdoor sources, and the contributions of indoor sources also cannot be ignored. Factors associated indoor and outdoor air exchange can influence the concentrations of indoor PM 2.5 and its constituents.

Fine particle receptor modeling in the atmosphere of Mexico City.

PubMed

Vega, Elizabeth; Lowenthal, Douglas; Ruiz, Hugo; Reyes, Elizabeth; Watson, John G; Chow, Judith C; Viana, Mar; Querol, Xavier; Alastuey, Andrés

2009-12-01

Source apportionment analyses were carried out by means of receptor modeling techniques to determine the contribution of major fine particulate matter (PM2.5) sources found at six sites in Mexico City. Thirty-six source profiles were determined within Mexico City to establish the fingerprints of particulate matter sources. Additionally, the profiles under the same source category were averaged using cluster analysis and the fingerprints of 10 sources were included. Before application of the chemical mass balance (CMB), several tests were carried out to determine the best combination of source profiles and species used for the fitting. CMB results showed significant spatial variations in source contributions among the six sites that are influenced by local soil types and land use. On average, 24-hr PM2.5 concentrations were dominated by mobile source emissions (45%), followed by secondary inorganic aerosols (16%) and geological material (17%). Industrial emissions representing oil combustion and incineration contributed less than 5%, and their contribution was higher at the industrial areas of Tlalnepantla (11%) and Xalostoc (8%). Other sources such as cooking, biomass burning, and oil fuel combustion were identified at lower levels. A second receptor model (principal component analysis, [PCA]) was subsequently applied to three of the monitoring sites for comparison purposes. Although differences were obtained between source contributions, results evidence the advantages of the combined use of different receptor modeling techniques for source apportionment, given the complementary nature of their results. Further research is needed in this direction to reach a better agreement between the estimated source contributions to the particulate matter mass.

Primary sources of PM2.5 organic aerosol in an industrial Mediterranean city, Marseille

NASA Astrophysics Data System (ADS)

El Haddad, I.; Marchand, N.; Wortham, H.; Piot, C.; Besombes, J.-L.; Cozic, J.; Chauvel, C.; Armengaud, A.; Robin, D.; Jaffrezo, J.-L.

2010-11-01

Marseille, the most important port of the Mediterranean Sea, represents a challenging case study for source apportionment exercises, combining an active photochemistry and multiple emission sources, including fugitive emissions from industrial sources and shipping. This paper presents a Chemical Mass Balance (CMB) approach based on organic markers and metals to apportion the primary sources of organic aerosol in Marseille, with a special focus on industrial emissions. Overall, the CMB model accounts for the major primary anthropogenic sources including motor vehicles, biomass burning, and the aggregate emissions from three industrial processes (HFO combustion/shipping, coke production and steel manufacturing) as well as some primary biogenic emissions. This source apportionment exercise is well corroborated by 14C measurements. Primary OC estimated by the CMB accounts on average for 22% and is dominated by the vehicular emissions that contribute on average for 17% of OC mass concentration (17% of PM2.5). Even though, industrial emissions contribute for only 2.3% of the total OC (7% of PM2.5), they are associated with ultrafine particles (Dp<80 nm) and high concentrations of Polycyclic Aromatic Hydrocarbons (PAH) and heavy metals such as Pb, Ni and V. On one hand, given that industrial emissions governed key primary markers, their omission would lead to substantial uncertainties in the CMB analysis performed in areas heavily impacted by such sources, hindering accurate estimation of non-industrial primary sources and secondary sources. This result implies that CMB modelling should not be a straightforward exercise and one have to carefully investigate the marker behaviours and trends beforehand, especially in complex environments such as Marseille. On the other hand, being associated with bursts of submicron particles and carcinogenic and mutagenic components such as PAH, these emissions are most likely related with acute health outcomes and should be regulated despite their small contributions to OC. Another important result is the fact that 78% of OC mass cannot be attributed to the major primary sources and thus remains un-apportioned. We have consequently critically investigated the uncertainties underlying our CMB apportionments. While we have provided some evidence for photochemical decay of hopanes, this decay does not appear to significantly alter the CMB estimates of the total primary OC. Sampling artefacts and unaccounted primary sources also appear to marginally influence the amount of un-apportioned OC. Therefore, this significant amount of un-apportioned OC is mostly attributed to secondary organic carbon that appears to be the major component of OC, during the whole period of study.

[Chemical Compositions and Sources Apportionment of Re-suspended Dust in Jincheng].

PubMed

Wang, Yan; Peng, Lin; Li, Li-juan; Zhang, Teng; Liu, Hai-li; Mu, Ling

2016-01-15

In order to make effective plan to provide the scientific basis for prevention and control of re-suspended dust (RD), samples of particulate sources including RD and other pollution sources of Jincheng were collected. Elements, ions and carbon in particulate sources were analyzed. Enrichment factor, potential ecological risk assessment, and chemical mass balance model were used to analyze the chemical composition and the source of RD. The result indicated that the main components in RD of Jingeheng were Si, TC, Ca, OC, Al, Mg, Na, Fe, K and SO4(2-), contributing 61.14% of total mass of RD. The most abundant content of RD was crustal elements, and the ions were enriched in the fine particles. The mass fraction of OC in PM2. was higher, whereas the mass fraction of EC in PM10 was higher, indicating that secondary organic pollutants were mainly dominated in the fine particles. The dust PM2.5 and PM10 potential ecological risk indexes were extremely strong, and PM2.5 had higher ecological harm than PM10. Pb had the highest enrichment factor of 196.97 in PM2.5, which was followed by As, Cr, Ni, V, Zn and Cu, the enrichment factors of which were all greater than 10, indicating that they were apparently enriched and affected by human activities. Soil dust, construction dust, vehicle exhaust, and coal dust were the main sources of RD.

Particulate matter chemical component concentrations and sources in settings of household solid fuel use.

PubMed

Secrest, M H; Schauer, J J; Carter, E M; Baumgartner, J

2017-11-01

Particulate matter (PM) air pollution derives from combustion and non-combustion sources and consists of various chemical species that may differentially impact human health and climate. Previous reviews of PM chemical component concentrations and sources focus on high-income urban settings, which likely differ from the low- and middle-income settings where solid fuel (ie, coal, biomass) is commonly burned for cooking and heating. We aimed to summarize the concentrations of PM chemical components and their contributing sources in settings where solid fuel is burned. We searched the literature for studies that reported PM component concentrations from homes, personal exposures, and direct stove emissions under uncontrolled, real-world conditions. We calculated weighted mean daily concentrations for select PM components and compared sources of PM determined by source apportionment. Our search criteria yielded 48 studies conducted in 12 countries. Weighted mean daily cooking area concentrations of elemental carbon, organic carbon, and benzo(a)pyrene were 18.8 μg m -3 , 74.0 μg m -3 , and 155 ng m -3 , respectively. Solid fuel combustion explained 29%-48% of principal component/factor analysis variance and 41%-87% of PM mass determined by positive matrix factorization. Multiple indoor and outdoor sources impacted PM concentrations and composition in these settings, including solid fuel burning, mobile emissions, dust, and solid waste burning. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

AIRUSE-LIFE+: a harmonized PM speciation and source apportionment in 5 Southern European cities

NASA Astrophysics Data System (ADS)

Amato, F.; Alastuey, A.; Karanasiou, A.; Lucarelli, F.; Nava, S.; Calzolai, G.; Severi, M.; Becagli, S.; Gianelle, V. L.; Colombi, C.; Alves, C.; Custódio, D.; Nunes, T.; Cerqueira, M.; Pio, C.; Eleftheriadis, K.; Diapouli, E.; Reche, C.; Minguillón, M. C.; Manousakas, M.; Maggos, T.; Vratolis, S.; Harrison, R. M.; Querol, X.

2015-09-01

The AIRUSE-LIFE+ project aims at characterising similarities and heterogeneities in PM sources and contributions in urban areas from the Southern Europe. Once the main PMx sources are identified, AIRUSE aims at developing and testing the efficiency of specific and non-specific measures to improve urban air quality. This article reports the results of the source apportionment of PM10 and PM2.5 conducted at three urban background sites (Barcelona, Florence and Milan, BCN-UB, FI-UB, MLN-UB) one sub-urban background site (Athens, ATH-SUB) and one traffic site (Porto, POR-TR). After collecting 1047 PM10 and 1116 PM2.5 24 h samples from January 2013 to February 2014 simultaneously at the 5 cities, these were analysed for the contents of OC, EC, anions, cations, major and trace elements and levoglucosan. The USEPA PMF5 receptor model was applied to these datasets in a harmonised way for each city. The sum of vehicle exhaust and non-exhaust contributes within 3.9-10.8 μg m-3 (16-32 %) to PM10 and 2.3-9.4 μg m-3 (15-36 %) to PM2.5, although a fraction of secondary nitrate is also traffic-related but could not be estimated. Important contributions arise from secondary particles (nitrate, sulphate and organics) in PM2.5 (37-82 %) but also in PM10 (40-71 %) mostly at background sites, revealing the importance of abating gaseous precursors in designing air quality plans. Biomass burning (BB) contributions vary widely, from 14-24 % of PM10 in POR-TR, MLN-UB and FI-UB, 7 % in ATH-SUB to < 2 % in BCN-UB. In PM2.5, BB is the second most important source in MLN-UB (21 %) and in POR-TR (18 %), the third one in FI-UB (21 %) and ATH-SUB (11 %), but again negligible (< 2 %) in BCN-UB. This large variability among cities is mostly due to the degree of penetration of biomass for residential heating. In Barcelona natural gas is very well supplied across the city and used as fuel in 96 % of homes, while, in other cities, PM levels increase on an annual basis by 1-9 μg m-3 due to this source. Other significant sources are: - Local dust, 7-12 % of PM10 at SUB and UB sites and 19 % at the TR site, revealing a contribution from road dust resuspension. In PM2.5 percentages decrease to 2-7 % at SUB-UB sites and 15 % at the TR site. - Industries, mainly metallurgy, contributing 4-11 % of PM10 (5-12 % in PM2.5), but only at BCN-UB, POR-TR and MLN-UB. No clear impact of industrial emissions was found in FI-UB and ATH-SUB. - Natural contributions from sea salt (13 % of PM10 in POR-TR but only 2-7 % in the other cities) and Saharan dust (14 % in ATH-SUB), but less than 4 % in the other cities. During high pollution days, the largest specific source (i.e. excluding SSO and SNI) of PM10 and PM2.5 are: VEX+NEX in BCN-UB (27-22 %) and POR-TR (31-33 %), BB in FI-UB (30-33 %) and MLN-UB (35-26 %) and Saharan dust in ATH-SUB (52-45 %) During those days, there are also quite important Industrial contributions in BCN-UB (17-18 %) and Local dust in POR-TR (28-20 %).

Seasonal effect and source apportionment of polycyclic aromatic hydrocarbons in PM2.5

NASA Astrophysics Data System (ADS)

Khan, Md Firoz; Latif, Mohd Talib; Lim, Chee Hou; Amil, Norhaniza; Jaafar, Shoffian Amin; Dominick, Doreena; Mohd Nadzir, Mohd Shahrul; Sahani, Mazrura; Tahir, Norhayati Mohd

2015-04-01

This study aims to investigate distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) bound to fine particulate matter (PM2.5) captured in a semi-urban area in Malaysia during different seasons, and to assess their health risks. PM2.5 samples were collected using a high volume air sampler on quartz filter paper at a flow rate of 1 m3 min-1 for 24 h. PAHs on the filter paper were extracted with dichloromethane (DCM) using an ultrasonic centrifuge solid-phase extraction method and measured by gas chromatography-mass spectroscopy. The results showed that the range of PAHs concentrations in the study period was between 0.21 and 12.08 ng m-3. The concentrations of PAHs were higher during the south-west monsoon (0.21-12.08 ng m-3) compared to the north-east monsoon (0.68-3.80 ng m-3). The high molecular weight (HMW) PAHs (≥5 ring) are significantly prominent (>70%) compared to the low molecular weight (LMW) PAHs (≤4 ring) in PM2.5. The Spearman correlation indicates that the LMW and HMW PAHs correlate strongly among themselves. The diagnostic ratios (DRs) of I[c]P/I[c]P + BgP and B[a]P/B[g]P suggest that the HMW PAHs originated from fuel combustion sources. The source apportionment analysis of PAHs was resolved using DRs-positive matrix factorization (PMF)-multiple linear regression (MLR). The main sources identified were (a) gasoline combustion (65%), (b) diesel and heavy oil combustion (19%) and (c) natural gas and coal burning (15%). The health risk evaluation, by means of the lifetime lung cancer risk (LLCR), showed no potential carcinogenic risk from the airborne BaPeq (which represents total PAHs at the present study area in Malaysia). The seasonal LLCR showed that the carcinogenic risk of total PAHs were two fold higher during south-westerly monsoon compared to north-easterly monsoon.

Real-time chemical characterization of atmospheric particulate matter in China: A review

NASA Astrophysics Data System (ADS)

Li, Yong Jie; Sun, Yele; Zhang, Qi; Li, Xue; Li, Mei; Zhou, Zhen; Chan, Chak K.

2017-06-01

Atmospheric particulate matter (PM) pollution has become a major health threat accompanying the rapid economic development in China. For decades, filter-based offline chemical analyses have been the most widely adopted means to investigate PM and have provided much information for understanding this type of pollution in China. However, offline analyses have low time resolutions and the chemical information thus obtained fail to reflect the dynamic nature of the sources and the rapid processes leading to the severe PM pollution in China. In recent years, advances in real-time PM chemical characterization have created a new paradigm for PM studies in China. In this review, we summarize those advances, focusing on the most widely used mass spectrometric and ion chromatographic techniques. We describe the findings from those studies in terms of spatiotemporal variabilities, degree of neutralization and oxygenation, source apportionment, secondary formation, as well as collocated measurements of the chemical and physical (hygroscopic and optical) properties of PM. We also highlight the new insights gained from those findings and suggest future directions for further advancing our understanding of PM pollution in China via real-time chemical characterization.

Speciation of organic fractions does matter for aerosol source apportionment. Part 2: Intensive short-term campaign in the Paris area (France).

PubMed

Srivastava, D; Favez, O; Bonnaire, N; Lucarelli, F; Haeffelin, M; Perraudin, E; Gros, V; Villenave, E; Albinet, A

2018-09-01

The present study aimed at performing PM 10 source apportionment, using positive matrix factorization (PMF), based on filter samples collected every 4h at a sub-urban station in the Paris region (France) during a PM pollution event in March 2015 (PM 10 >50μgm -3 for several consecutive days). The PMF model allowed to deconvolve 11 source factors. The use of specific primary and secondary organic molecular markers favoured the determination of common sources such as biomass burning and primary traffic emissions, as well as 2 specific biogenic SOA (marine+isoprene) and 3 anthropogenic SOA (nitro-PAHs+oxy-PAHs+phenolic compounds oxidation) factors. This study is probably the first one to report the use of methylnitrocatechol isomers as well as 1-nitropyrene to apportion secondary OA linked to biomass burning emissions and primary traffic emissions, respectively. Secondary organic carbon (SOC) fractions were found to account for 47% of the total OC. The use of organic molecular markers allowed the identification of 41% of the total SOC composed of anthropogenic SOA (namely, oxy-PAHs, nitro-PAHs and phenolic compounds oxidation, representing 15%, 9%, 11% of the total OC, respectively) and biogenic SOA (marine+isoprene) (6% in total). Results obtained also showed that 35% of the total SOC originated from anthropogenic sources and especially PAH SOA (oxy-PAHs+nitro-PAHs), accounting for 24% of the total SOC, highlighting its significant contribution in urban influenced environments. Anthropogenic SOA related to nitro-PAHs and phenolic compounds exhibited a clear diurnal pattern with high concentrations during the night indicating the prominent role of night-time chemistry but with different chemical processes involved. Copyright © 2018 Elsevier B.V. All rights reserved.

Seasonal variations and source apportionment of complex polycyclic aromatic hydrocarbon mixtures in particulate matter in an electronic waste and urban area in South China.

PubMed

Chen, She-Jun; Wang, Jing; Wang, Tao; Wang, Ting; Mai, Bi-Xian; Simonich, Staci L Massey

2016-12-15

Complex polycyclic aromatic hydrocarbon (PAH) mixtures including parent PAHs, high molecular weight PAHs (MW 302 PAHs), and halogenated PAHs (HPAHs) were measured in particulate matter (PM) in an urban area and a rural electronic waste area in South China. The concentrations of MW < 302 PAHs at two sites were not significantly different with annual means of 23.2 ± 17.2 and 33.7 ± 29.0 ng/m 3 , respectively. However the concentrations of both MW 302 PAHs (5.35 ± 3.72 ng/m 3 ) and HPAH (49.9 pg/m 3 ) were significantly higher at the e-waste site than the urban site (2.81 ± 2.36 ng/m 3 and 28.2 ± 28.5 pg/m 3 ), suggesting e-waste recycling being a significant source of these PAHs. The majority of PAHs exhibited higher concentrations in winter and spring and lower concentrations in fall and summer. Meteorological conditions and increased emissions of PAHs in northern China due to domestic heating in colder seasons are important factors influencing the PAH seasonal variations. Source apportionment by the chemical mass balance (CMB) model indicated that residential stoves (coal combustion), industrial boilers (coal combustion), biomass burning, and vehicular emission accounted for 38 ± 14%, 30 ± 11%, 22 ± 22%, and 10 ± 7% of the PAHs in the urban PM, respectively. Comparable contributions from these sources were also observed for PM at the e-waste site. PAH emission factors are needed for primitive e-waste recycling to further understand the importance of this source to ambient air. Copyright © 2016 Elsevier B.V. All rights reserved.

Associations between Source-Specific Fine Particulate Matter and Emergency Department Visits for Respiratory Disease in Four U.S. Cities

PubMed Central

Krall, Jenna R.; Mulholland, James A.; Russell, Armistead G.; Balachandran, Sivaraman; Winquist, Andrea; Tolbert, Paige E.; Waller, Lance A.; Sarnat, Stefanie Ebelt

2016-01-01

Background: Short-term exposure to ambient fine particulate matter (PM2.5) concentrations has been associated with increased mortality and morbidity. Determining which sources of PM2.5 are most toxic can help guide targeted reduction of PM2.5. However, conducting multicity epidemiologic studies of sources is difficult because source-specific PM2.5 is not directly measured, and source chemical compositions can vary between cities. Objectives: We determined how the chemical composition of primary ambient PM2.5 sources varies across cities. We estimated associations between source-specific PM2.5 and respiratory disease emergency department (ED) visits and examined between-city heterogeneity in estimated associations. Methods: We used source apportionment to estimate daily concentrations of primary source-specific PM2.5 for four U.S. cities. For sources with similar chemical compositions between cities, we applied Poisson time-series regression models to estimate associations between source-specific PM2.5 and respiratory disease ED visits. Results: We found that PM2.5 from biomass burning, diesel vehicle, gasoline vehicle, and dust sources was similar in chemical composition between cities, but PM2.5 from coal combustion and metal sources varied across cities. We found some evidence of positive associations of respiratory disease ED visits with biomass burning PM2.5; associations with diesel and gasoline PM2.5 were frequently imprecise or consistent with the null. We found little evidence of associations with dust PM2.5. Conclusions: We introduced an approach for comparing the chemical compositions of PM2.5 sources across cities and conducted one of the first multicity studies of source-specific PM2.5 and ED visits. Across four U.S. cities, among the primary PM2.5 sources assessed, biomass burning PM2.5 was most strongly associated with respiratory health. Citation: Krall JR, Mulholland JA, Russell AG, Balachandran S, Winquist A, Tolbert PE, Waller LA, Sarnat SE. 2017. Associations between source-specific fine particulate matter and emergency department visits for respiratory disease in four U.S. cities. Environ Health Perspect 125:97–103; http://dx.doi.org/10.1289/EHP271 PMID:27315241

Associations between Source-Specific Fine Particulate Matter and Emergency Department Visits for Respiratory Disease in Four U.S. Cities.

PubMed

Krall, Jenna R; Mulholland, James A; Russell, Armistead G; Balachandran, Sivaraman; Winquist, Andrea; Tolbert, Paige E; Waller, Lance A; Sarnat, Stefanie Ebelt

2017-01-01

Short-term exposure to ambient fine particulate matter (PM2.5) concentrations has been associated with increased mortality and morbidity. Determining which sources of PM2.5 are most toxic can help guide targeted reduction of PM2.5. However, conducting multicity epidemiologic studies of sources is difficult because source-specific PM2.5 is not directly measured, and source chemical compositions can vary between cities. We determined how the chemical composition of primary ambient PM2.5 sources varies across cities. We estimated associations between source-specific PM2.5 and respiratory disease emergency department (ED) visits and examined between-city heterogeneity in estimated associations. We used source apportionment to estimate daily concentrations of primary source-specific PM2.5 for four U.S. cities. For sources with similar chemical compositions between cities, we applied Poisson time-series regression models to estimate associations between source-specific PM2.5 and respiratory disease ED visits. We found that PM2.5 from biomass burning, diesel vehicle, gasoline vehicle, and dust sources was similar in chemical composition between cities, but PM2.5 from coal combustion and metal sources varied across cities. We found some evidence of positive associations of respiratory disease ED visits with biomass burning PM2.5; associations with diesel and gasoline PM2.5 were frequently imprecise or consistent with the null. We found little evidence of associations with dust PM2.5. We introduced an approach for comparing the chemical compositions of PM2.5 sources across cities and conducted one of the first multicity studies of source-specific PM2.5 and ED visits. Across four U.S. cities, among the primary PM2.5 sources assessed, biomass burning PM2.5 was most strongly associated with respiratory health. Citation: Krall JR, Mulholland JA, Russell AG, Balachandran S, Winquist A, Tolbert PE, Waller LA, Sarnat SE. 2017. Associations between source-specific fine particulate matter and emergency department visits for respiratory disease in four U.S. cities. Environ Health Perspect 125:97-103; http://dx.doi.org/10.1289/EHP271.

Beijing ambient particle exposure accelerates atherosclerosis in ApoE knockout mice.

PubMed

Chen, Tian; Jia, Guang; Wei, Yongjie; Li, Jiucun

2013-11-25

Air pollution is associated with significant adverse health effects including increased cardiovascular morbidity and mortality. However research on the cardiovascular effect of "real-world" exposure to ambient particulate matter (PM) in susceptible animal model is very limited. In this study, we aimed to investigate the association between Beijing ambient particle exposure and the atherosclerosis development in the apolipoprotein E knockout mice (ApoE(-/-) mice). Two parallel exposure chambers were used for whole body exposure among ApoE knockout mice. One of the chambers was supplied with untreated ambient air (PM group) and the other chamber was treated with ambient air filtered by high-efficiency particulate air (HEPA) filter (FA group). Twenty mice were divided into two groups and exposed to ambient PM (n=10 for PM group) or filtered air (n=10 for FA group) for two months from January 18th to March 18th, 2010. During the exposure, the mass concentrations of PM2.5 and PM10 in the two chambers were continuously monitored. Additionally, a receptor source apportionment model of chemical mass balance using 19 organic tracers was applied to determine the contributions of sources on the PM2.5 in terms of natural gas, diesel vehicle, gasoline vehicle, coal burning, vegetable debris, biomass burning and cooking. At the end of the two-month exposure, biomarkers of oxidative stress, inflammation and lipid metabolism in bronchoalveolar lavage fluid (BAL) and blood samples were determined and the plaque area on the aortic endothelium was quantified. In the experiment, the concentrations of PM10 and PM2.5 in PM chamber were 99.45μg/m(3) and 61.0μg/m(3) respectively, while PM2.5 in FA chamber was 17.6μg/m(3). Source apportionment analysis by organic tracers showed that gasoline vehicle (39.9%) and coal burning (24.3%) emission were the two major sources contributing to the mass concentration of PM2.5 in Beijing. Among the ApoE knockout mice, the PM group were significantly higher than the FA group in terms of serum total cholesterol, low-density lipoprotein, tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein as well as TNF-alpha and interleukin-6 in BAL. Also the total antioxidant capacity and oxidized low-density lipoprotein were significantly different between the two groups. In addition, pathological analysis of aortic arch reveals that the plaques area in the PM group increased significantly compared to the FA group. Our results demonstrated that ambient PM exposure could induce considerable oxidative stress and systemic inflammation in ApoE knockout mice and contribute to the progression of atherosclerosis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Source apportionment of PM2.5 chemically speciated mass and particle number concentrations in New York City

NASA Astrophysics Data System (ADS)

Masiol, M.; Hopke, P. K.; Felton, H. D.; Frank, B. P.; Rattigan, O. V.; Wurth, M. J.; LaDuke, G. H.

2017-01-01

The major sources of fine particulate matter (PM2.5) in New York City (NYC) were apportioned by applying positive matrix factorization (PMF) to two different sets of particle characteristics: mass concentrations using chemical speciation data and particle number concentrations (PNC) using number size distribution, continuously monitored gases, and PM2.5 data. Post-processing was applied to the PMF results to: (i) match with meteorological data, (ii) use wind data to detect the likely locations of the local sources, and (iii) use concentration weighted trajectory models to assess the strength of potential regional/transboundary sources. Nine sources of PM2.5 mass were apportioned and identified as: secondary ammonium sulfate, secondary ammonium nitrate, road traffic exhaust, crustal dust, fresh sea-salt, aged sea-salt, biomass burning, residual oil/domestic heating and zinc. The sources of PNC were investigated using hourly average number concentrations in six size bins, gaseous air pollutants, mass concentrations of PM2.5, particulate sulfate, OC, and EC. These data were divided into 3 periods indicative of different seasonal conditions. Five sources were resolved for each period: secondary particles, road traffic, NYC background pollution (traffic and oil heating largely in Manhattan), nucleation and O3-rich aerosol. Although traffic does not account for large amounts of PM2.5 mass, it was the main source of particles advected from heavily trafficked zones. The use of residual oil had limited impacts on PM2.5 mass but dominates PNC in cold periods.

Assessment of Contribution of Contemporary Carbon Sources to Size-Fractionated Particulate Matter and Time-Resolved Bulk Particulate Matter Using the Measurement of Radiocarbon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hwang, H M; Young, T M; Buchholz, B A

2009-04-16

This study was motivated by a desire to improve understanding of the sources contributing to the carbon that is an important component of airborne particulate matter (PM). The ultimate goal of this project was to lay a ground work for future tools that might be easily implemented with archived or routinely collected samples. A key feature of this study was application of radiocarbon measurement that can be interpreted to indicate the relative contributions from fossil and non-fossil carbon sources of atmospheric PM. Size-resolved PM and time-resolved PM{sub 10} collected from a site in Sacramento, CA in November 2007 (Phase I)more » and March 2008 (Phase II) were analyzed for radiocarbon and source markers such as levoglucosan, cholesterol, and elemental carbon. Radiocarbon data indicates that the contributions of non-fossil carbon sources were much greater than that from fossil carbon sources in all samples. Radiocarbon and source marker measurements confirm that a greater contribution of non-fossil carbon sources in Phase I samples was highly likely due to residential wood combustion. The present study proves that measurement of radiocarbon and source markers can be readily applied to archived or routinely collected samples for better characterization of PM sources. More accurate source apportionment will support ARB in developing more efficient control strategies.« less

Source identification of particulate matter in a semi-urban area of Malaysia using multivariate techniques.

PubMed

Wahid, N B A; Latif, M T; Suan, L S; Dominick, D; Sahani, M; Jaafar, S A; Mohd Tahir, N

2014-03-01

This study aims to determine the composition and sources of particulate matter with an aerodynamic diameter of 10 μm or less (PM10) in a semi-urban area. PM10 samples were collected using a high volume sampler. Heavy metals (Fe, Zn, Pb, Mn, Cu, Cd and Ni) and cations (Na(+), K(+), Ca(2+) and Mg(2+)) were detected using inductively coupled plasma mass spectrometry, while anions (SO4 (2-), NO3 (-), Cl(-) and F(-)) were analysed using Ion Chromatography. Principle component analysis and multiple linear regressions were used to identify the source apportionment of PM10. Results showed the average concentration of PM10 was 29.5 ± 5.1 μg/m(3). The heavy metals found were dominated by Fe, followed by Zn, Pb, Cu, Mn, Cd and Ni. Na(+) was the dominant cation, followed by Ca(2+), K(+) and Mg(2+), whereas SO4 (2-) was the dominant anion, followed by NO3 (-), Cl(-) and F(-). The main sources of PM10 were the Earth's crust/road dust, followed by vehicle emissions, industrial emissions/road activity, and construction/biomass burning.

PM10 source apportionment applying PMF and chemical tracer analysis to ship-borne measurements in the Western Mediterranean

NASA Astrophysics Data System (ADS)

Bove, M. C.; Brotto, P.; Calzolai, G.; Cassola, F.; Cavalli, F.; Fermo, P.; Hjorth, J.; Massabò, D.; Nava, S.; Piazzalunga, A.; Schembari, C.; Prati, P.

2016-01-01

A PM10 sampling campaign was carried out on board the cruise ship Costa Concordia during three weeks in summer 2011. The ship route was Civitavecchia-Savona-Barcelona-Palma de Mallorca-Malta (Valletta)-Palermo-Civitavecchia. The PM10 composition was measured and utilized to identify and characterize the main PM10 sources along the ship route through receptor modelling, making use of the Positive Matrix Factorization (PMF) algorithm. A particular attention was given to the emissions related to heavy fuel oil combustion by ships, which is known to be also an important source of secondary sulphate aerosol. Five aerosol sources were resolved by the PMF analysis. The primary contribution of ship emissions to PM10 turned out to be (12 ± 4)%, while secondary ammonium sulphate contributed by (35 ± 5)%. Approximately, 60% of the total sulphate was identified as secondary aerosol while about 20% was attributed to heavy oil combustion in ship engines. The measured concentrations of methanesulphonic acid (MSA) indicated a relevant contribution to the observed sulphate loading by biogenic sulphate, formed by the atmospheric oxidation of dimethyl sulphide (DMS) emitted by marine phytoplankton.

Advanced source apportionment of carbonaceous aerosols by coupling offline AMS and radiocarbon size-segregated measurements over a nearly 2-year period

NASA Astrophysics Data System (ADS)

Vlachou, Athanasia; Daellenbach, Kaspar R.; Bozzetti, Carlo; Chazeau, Benjamin; Salazar, Gary A.; Szidat, Soenke; Jaffrezo, Jean-Luc; Hueglin, Christoph; Baltensperger, Urs; El Haddad, Imad; Prévôt, André S. H.

2018-05-01

Carbonaceous aerosols are related to adverse human health effects. Therefore, identification of their sources and analysis of their chemical composition is important. The offline AMS (aerosol mass spectrometer) technique offers quantitative separation of organic aerosol (OA) factors which can be related to major OA sources, either primary or secondary. While primary OA can be more clearly separated into sources, secondary (SOA) source apportionment is more challenging because different sources - anthropogenic or natural, fossil or non-fossil - can yield similar highly oxygenated mass spectra. Radiocarbon measurements provide unequivocal separation between fossil and non-fossil sources of carbon. Here we coupled these two offline methods and analysed the OA and organic carbon (OC) of different size fractions (particulate matter below 10 and 2.5 µm - PM10 and PM2.5, respectively) from the Alpine valley of Magadino (Switzerland) during the years 2013 and 2014 (219 samples). The combination of the techniques gave further insight into the characteristics of secondary OC (SOC) which was rather based on the type of SOC precursor and not on the volatility or the oxidation state of OC, as typically considered. Out of the primary sources separated in this study, biomass burning OC was the dominant one in winter, with average concentrations of 5.36 ± 2.64 µg m-3 for PM10 and 3.83 ± 1.81 µg m-3 for PM2.5, indicating that wood combustion particles were predominantly generated in the fine mode. The additional information from the size-segregated measurements revealed a primary sulfur-containing factor, mainly fossil, detected in the coarse size fraction and related to non-exhaust traffic emissions with a yearly average PM10 (PM2.5) concentration of 0.20 ± 0.24 µg m-3 (0.05 ± 0.04 µg m-3). A primary biological OC (PBOC) was also detected in the coarse mode peaking in spring and summer with a yearly average PM10 (PM2.5) concentration of 0.79 ± 0.31 µg m-3 (0.24 ± 0.20 µg m-3). The secondary OC was separated into two oxygenated, non-fossil OC factors which were identified based on their seasonal variability (i.e. summer and winter oxygenated organic carbon, OOC) and a third anthropogenic OOC factor which correlated with fossil OC mainly peaking in winter and spring, contributing on average 13 % ± 7 % (10 % ± 9 %) to the total OC in PM10 (PM2.5). The winter OOC was also connected to anthropogenic sources, contributing on average 13 % ± 13 % (6 % ± 6 %) to the total OC in PM10 (PM2.5). The summer OOC (SOOC), stemming from oxidation of biogenic emissions, was more pronounced in the fine mode, contributing on average 43 % ± 12 % (75 % ± 44 %) to the total OC in PM10 (PM2.5). In total the non-fossil OC significantly dominated the fossil OC throughout all seasons, by contributing on average 75 % ± 24 % to the total OC. The results also suggested that during the cold period the prevailing source was residential biomass burning while during the warm period primary biological sources and secondary organic aerosol from the oxidation of biogenic emissions became important. However, SOC was also formed by aged fossil fuel combustion emissions not only in summer but also during the rest of the year.

AIRUSE-LIFE+: a harmonized PM speciation and source apportionment in five southern European cities

NASA Astrophysics Data System (ADS)

Amato, Fulvio; Alastuey, Andrés; Karanasiou, Angeliki; Lucarelli, Franco; Nava, Silvia; Calzolai, Giulia; Severi, Mirko; Becagli, Silvia; Gianelle, Vorne L.; Colombi, Cristina; Alves, Celia; Custódio, Danilo; Nunes, Teresa; Cerqueira, Mario; Pio, Casimiro; Eleftheriadis, Konstantinos; Diapouli, Evangelia; Reche, Cristina; Cruz Minguillón, María; Manousakas, Manousos-Ioannis; Maggos, Thomas; Vratolis, Stergios; Harrison, Roy M.; Querol, Xavier

2016-03-01

The AIRUSE-LIFE+ project aims at characterizing similarities and heterogeneities in particulate matter (PM) sources and contributions in urban areas from southern Europe. Once the main PMx sources are identified, AIRUSE aims at developing and testing the efficiency of specific and non-specific measures to improve urban air quality. This article reports the results of the source apportionment of PM10 and PM2.5 conducted at three urban background sites (Barcelona, Florence and Milan, BCN-UB, FI-UB and MLN-UB), one suburban background site (Athens, ATH-SUB) and one traffic site (Porto, POR-TR). After collecting 1047 PM10 and 1116 PM2.5 24 h samples during 12 months (from January 2013 on) simultaneously at the five cities, these were analysed for the contents of OC, EC, anions, cations, major and trace elements and levoglucosan. The USEPA PMF5 receptor model was applied to these data sets in a harmonized way for each city. The sum of vehicle exhaust (VEX) and non-exhaust (NEX) contributes between 3.9 and 10.8 µg m-3 (16-32 %) to PM10 and 2.3 and 9.4 µg m-3 (15-36 %) to PM2.5, although a fraction of secondary nitrate is also traffic-related but could not be estimated. Important contributions arise from secondary particles (nitrate, sulfate and organics) in PM2.5 (37-82 %) but also in PM10 (40-71 %), mostly at background sites, revealing the importance of abating gaseous precursors in designing air quality plans. Biomass burning (BB) contributions vary widely, from 14-24 % of PM10 in POR-TR, MLN-UB and FI-UB, 7 % in ATH-SUB, to < 2 % in BCN-UB. In PM2.5, BB is the second most important source in MLN-UB (21 %) and in POR-TR (18 %), the third one in FI-UB (21 %) and ATH-SUB (11 %), but is again negligible (< 2 %) in BCN-UB. This large variability among cities is mostly due to the degree of penetration of biomass for residential heating. In Barcelona natural gas is very well supplied across the city and is used as fuel in 96 % of homes, while in other cities, PM levels increase on an annual basis by 1-9 µg m-3 due to biomass burning influence. Other significant sources are the following. - Local dust, 7-12 % of PM10 at SUB and UB sites and 19 % at the TR site, revealing a contribution from road dust resuspension. In PM2.5 percentages decrease to 2-7 % at SUB-UB sites and 15 % at the TR site. - Industry, mainly metallurgy, contributing 4-11 % of PM10 (5-12 % in PM2.5), but only at BCN-UB, POR-TR and MLN-UB. No clear impact of industrial emissions was found in FI-UB and ATH-SUB. - Natural contributions from sea salt (13 % of PM10 in POR-TR, but only 2-7 % in the other cities) and Saharan dust (14 % in ATH-SUB, but less than 4 % in the other cities). During high pollution days, the largest sources (i.e. excluding secondary aerosol factors) of PM10 and PM2.5 are VEX + NEX in BCN-UB (27-22 %) and POR-TR (31-33 %), BB in FI-UB (30-33 %) and MLN-UB (35-26 %) and Saharan dust in ATH-SUB (52-45 %). During those days, there are also quite important industrial contributions in BCN-UB (17-18 %) and local dust in POR-TR (28-20 %).

Chemical composition of PM2.5 at an urban site of Chengdu in southwestern China

NASA Astrophysics Data System (ADS)

Tao, Jun; Cheng, Tiantao; Zhang, Renjian; Cao, Junji; Zhu, Lihua; Wang, Qiyuan; Luo, Lei; Zhang, Leiming

2013-07-01

PM2.5 aerosols were sampled in urban Chengdu from April 2009 to January 2010, and their chemical compositions were characterized in detail for elements, water soluble inorganic ions, and carbonaceous matter. The annual average of PM2.5 was 165 μg m-3, which is generally higher than measurements in other Chinese cities, suggesting serious particulate pollution issues in the city. Water soluble ions contributed 43.5% to the annual total PM2.5 mass, carbonaceous aerosols including elemental carbon and organic carbon contributed 32.0%, and trace elements contributed 13.8%. Distinct daily and seasonal variations were observed in the mass concentrations of PM2.5 and its components, reflecting the seasonal variations of different anthropogenic and natural sources. Weakly acidic to neutral particles were found for PM2.5. Major sources of PM2.5 identified from source apportionment analysis included coal combustion, traffic exhaust, biomass burning, soil dust, and construction dust emissions. The low nitrate: sulfate ratio suggested that stationary emissions were more important than vehicle emissions. The reconstructed masses of ammonium sulfate, ammonium nitrate, particulate carbonaceous matter, and fine soil accounted for 79% of the total measured PM2.5 mass; they also accounted for 92% of the total measured particle scattering.

Diagnosis of aged prescribed burning plumes impacting an urban area.

PubMed

Lee, Sangil; Kim, Hyeon K; Yan, Bo; Cobb, Charles E; Hennigan, Chris; Nichols, Sara; Chamber, Michael; Edgerton, Eric S; Jansen, John J; Hu, Yongtao; Zheng, Mei; Weber, Rodney J; Russell, Armistead G

2008-03-01

An unanticipated wind shift led to the advection of plumes from two prescribed burning sites that impacted Atlanta, GA, producing a heavy smoke event late in the afternoon on February 28, 2007. Observed PM2.5 concentrations increased to over 140 microg/m3 and O3 concentrations up to 30 ppb in a couple of hours, despite the late hour in February when photochemistry is less vigorous. A detailed investigation of PM2.5 chemical composition and source apportionment analysis showed that the increase in PM2.5 mass was driven mainly by organic carbon (OC). However, both results from source apportionment and an observed nonlinear relationship between OC and PM2.5 potassium (K) indicate that the increased OC was not due solely to primary emissions. Most of the OC was water-soluble organic carbon (WSOC) and was dominated by hydrophobic compounds. The data are consistent with large enhancements in isoprenoid (isoprene and monoterpenes) and other volatile organic compounds emitted from prescribed burning that led to both significant O3 and secondary organic aerosol (SOA) production. Formation of oligomers from oxidation products of isoprenoid compounds or condensation of volatile organic compounds (VOCs) with multiple functional groups emitted during prescribed burning appears to be a major component of the secondary organic contributor of the SOA. The results from this study imply that enhanced emissions due to the fire itself and elevated temperature in the burning region should be considered in air quality models (e.g., receptor and emission-based models) to assess impacts of prescribed burning emissions on ambient air quality.

Source apportionment of organic aerosol across Houston, TX during DISCOVER-AQ

NASA Astrophysics Data System (ADS)

Yoon, S.; Clark, A. E.; Ortiz, S. M.; Usenko, S.; Sheesley, R. J.

2015-12-01

As part of the ground-based sampling efforts during DISCOVER-AQ's Houston month-long campaign in September 2013, atmospheric particulate matter (PM) samples were collected at four sites: Moody Tower (urban), Manvel Croix (southern suburb), Conroe (northern suburb), and La Porte (urban industrial). The Houston metropolitan area, especially the Houston Ship Channel, is a densely industrialized urban city with large concentrations of petroleum refining, petrochemical manufacturing, and heavy traffic during peak hours. Due to these and other emission sources, the area is heavily impacted by ambient PM. This study will be looking at fine PM (diameter less than 2.5µm, PM2.5) from all four sites. PM2.5fraction is relevant for understanding fate and transport of organic contaminants and is widely known to negatively impact human health. Chemical analysis including radiocarbon (14C) and organic tracer measurements (polycyclic aromatic hydrocarbons, alkanes, hopanes, steranes, and levoglucosan) were used for source apportionment. The 14C measurements constrained CMB results to estimate both primary and secondary contributions to total organic carbon (TOC). Results indicate that Moody Tower had consistent primary motor vehicle exhaust contribution (18-27%) and a fossil secondary organic aerosol (SOA) contribution from 5-33% depending on atmospheric conditions. Conroe had a lower contribution of motor vehicle exhaust (5-10%) and similarly variable fraction of fossil SOA (4-25%). Manvel Croix had an interim motor vehicle contribution (9-15%) with a variable fossil SOA (5-30%). For contemporary OC, there was minimal contribution of wood smoke during examined weeks (0-9%) but larger contributor of biogenic SOA ranging from 40-75% at Moody Tower, 56-81% at Manvel Croix and 60-79% at Conroe. Overall, the motor vehicle contribution was consistent at each site during the analysis week, biogenic SOA was consistently high, while fossil SOA showed the most variability.

[Application of ICP-MS and ICP-AES for Studying on Source Apportionment of PM2.5 during Haze Weather in Urban Beijing].

PubMed

Chen, Xi; Du, Peng; Guan, Qing; Feng, Xu; Xu, Dong-qun; Lin, Shao-bin

2015-06-01

To investigate the characteristics of chemical constitute and pollution sources of aerosol fine particulate matter during haze-fog day in Beijing in winter 2013. The samples of PM2.5 were collected in Beijing from January to February, 2013. The technique of ICP-MS and ICP-AES coupled with procedure of bathing-ultrasonic extraction was applied to determine the concentration of 40 elements in the aerosol samples to analyze the characteristics of elements distribution statistically. The absolute principal factor method was used to apportion the pollution sources of PM2.5 during the haze weather in Beijing city in winter 2013. The results showed that during the period of sampling, the volume concentration of Li, Mn, Pb, S etc. obeyed normal distribution approximately, and according to National Ambient Air Quality Standard issued by Ministry of Environmental Protection of the People's Republic of China, the geometric mean concentration of As was twice the annual limit of standard reference, while Pb of some aerosol samples beyond the annual limit of standard reference respectively. The mass fraction of Fe, Zn, Pb, Ti accounted for over 0.1%, while that of Mn, Cu, As, Se etc. 0.01%. These elements were primary inorganic pollutants, and especially the hazards and sources of As and Pb should be concerned. There were 6 main pollution sources were chosen by the factor analysis method, including industrial dust and human beings activities, biomass combustion and building dust, soil and sand dusts, fossil fuel, electronic waste and metal smelting, with the variance contribution rate of 40.3%, 27.0%, 9.1%, 4.9%, 4.8% and 4.6% respectively. ICP-MS and ICP-AES can be applied to analyzing multi-elements in PM2.5 accurately and quickly to facilitate source apportionment, and it indicated that the relevant pollution sources should be considered and the effect of regional transferring of haze pollution sources should be taken into account, and specific measures should be taken for control.

The Effects of Particulate Matter Sources on Daily Mortality: A Case-Crossover Study of Barcelona, Spain

PubMed Central

Tobias, Aurelio; Querol, Xavier; Alastuey, Andrés; Amato, Fulvio; Pey, Jorge; Pérez, Noemí; Sunyer, Jordi

2011-01-01

Background: Dozens of studies link acute exposure to particulate matter (PM) air pollution with premature mortality and morbidity, but questions remain about which species and sources in the vast PM mixture are responsible for the observed health effects. Although a few studies exist on the effects of species and sources in U.S. cities, European cities—which have a higher proportion of diesel engines and denser urban populations—have not been well characterized. Information on the effects of specific sources could aid in targeting pollution control and in articulating the biological mechanisms of PM. Objectives: Our study examined the effects of various PM sources on daily mortality for 2003 through 2007 in Barcelona, a densely populated city in the northeast corner of Spain. Methods: Source apportionment for PM ≤ 2.5 μm and ≤ 10 µm in aerodynamic diameter (PM2.5 and PM10) using positive matrix factorization identified eight different factors. Case-crossover regression analysis was used to estimate the effects of each factor. Results: Several sources of PM2.5, including vehicle exhaust, fuel oil combustion, secondary nitrate/organics, minerals, secondary sulfate/organics, and road dust, had statistically significant associations (p < 0.05) with all-cause and cardiovascular mortality. Also, in some cases relative risks for a respective interquartile range increase in concentration were higher for specific sources than for total PM2.5 mass. Conclusions: These results along with those from our multisource models suggest that traffic, sulfate from shipping and long-range transport, and construction dust are important contributors to the adverse health effects linked to PM. PMID:21846610

Organic tracer-based source analysis of PM2.5 organic and elemental carbon: A case study at Dongguan in the Pearl River Delta, China

NASA Astrophysics Data System (ADS)

Wang, Qiong Qiong; Huang, X. H. Hilda; Zhang, Ting; Zhang, Qingyan; Feng, Yongming; Yuan, Zibing; Wu, Dui; Lau, Alexis K. H.; Yu, Jian Zhen

2015-10-01

Organic carbon (OC) and elemental carbon (EC) are major constituents of PM2.5 and their source apportionment remains a challenging task due to the great diversity of their sources and lack of source-specific tracer data. In this work, sources of OC and EC are investigated using positive matrix factorization (PMF) analysis of PM2.5 chemical composition data, including major ions, OC, EC, elements, and organic molecular source markers, for a set of 156 filter samples collected over three years from 2010 to 2012 at Dongguan in the Pearl River Delta, China. The key organic tracers include levoglucosan, mannosan, hopanes, C27-C33n-alkanes, and polycyclic aromatic hydrocarbons (PAHs). Using these species as input for the PMF model, nine factors were resolved. Among them, biomass burning and coal combustion were significant sources contributing 15-17% of OC and 24-30% and 34-35% of EC, respectively. Industrial emissions and ship emissions, identified through their characteristic metal signatures, contributed 16-24% and 7-8% of OC and 8-11% and 16-17% of EC, respectively. Vehicle exhaust was a less significant source, accounting for 3-4% of OC and 5-8% of EC. Secondary OC, taken to be the sum of OC present in secondary sulfate and nitrate formation source factors, made up 27-36% of OC. Plastic burning, identified through 1,3,5-triphenylbenzene as a tracer, was a less important source for OC(≤4%) and EC (5-10%), but a significant source for PAHs at this site. The utility of organic source tracers was demonstrated by comparing PMF runs with different combinations of organic tracers removed from the input species list. Levoglucosan and mannosan were important additions to distinguish biomass burning from coal combustion by reducing collinearity among source profiles. Inclusion of hopanes and 1,3,5-triphenylbenzene was found to be necessary in resolving the less significant sources vehicle exhaust and plastic burning. Inclusion of C27-C33n-alkanes and PAHs can influence the source profiles resolved by PMF and thereby affect the source contributions to OC and EC. Considerably more OC (44% vs. 27% of OC) was apportioned to the secondary factors when only major components were considered in comparison with the PMF analysis with the full suite of organic tracers, mainly at the expense of coal combustion and industrial emissions. EC apportionment to the few major combustion sources was found more sensitive to inclusion of organic tracers than OC apportionment, with PAHs playing a prominent role. This work demonstrates the importance of having distinct organic tracers in identifying and quantifying OC and EC sources.

Identification and quantification of indoor air pollutant sources within a residential academic campus.

PubMed

Suryawanshi, Shalini; Chauhan, Amit Singh; Verma, Ritika; Gupta, Tarun

2016-11-01

There is a growing concern regarding the adverse health effects due to indoor air pollution in developing countries including India. Hence, it becomes important to study the causes and sources of indoor air pollutants. This study presents the indoor concentrations of PM0.6 (particles with aerodynamic diameter less than 0.6μm) and identifies sources leading to indoor air pollution. Indoor air samples were collected at IIT Kanpur campus. Ninety-eight PM0.6 samples were collected during November 2013 to September 2014. PM0.6 concentration was measured using a single stage impactor type PM0.6 sampler. The average PM0.6 concentration indoor was about 94.44μg/m(3). Samples collected were then analysed for metal concentrations using ICP-OES (Inductively Coupled Plasma - Optical Emission Spectrometer). Eight metals Ba, Ca, Cr, Cu, Fe, Mg, Ni and Pb were quantified from PM samples using ICP-OES. Positive Matrix Factorization (PMF) was used for source apportionment of indoor air pollution. PMF is a factor analysis tool which helps in resolving the profile and contribution of the sources from an unknown mixture. Five possible sources of indoor pollutants were identified by factor analysis - (1) Coal combustion (21.8%) (2) Tobacco smoking (9.8%) (3) Wall dust (25.7%) (4) Soil particles (17.5%) (5) Wooden furniture/paper products (25.2%). Copyright © 2016 Elsevier B.V. All rights reserved.

Source apportionment of PM2.5 at urban and suburban areas of the Pearl River Delta region, south China - With emphasis on ship emissions.

PubMed

Tao, Jun; Zhang, Leiming; Cao, Junji; Zhong, Liuju; Chen, Dongsheng; Yang, Yihong; Chen, Duohong; Chen, Laiguo; Zhang, Zhisheng; Wu, Yunfei; Xia, Yunjie; Ye, Siqi; Zhang, Renjian

2017-01-01

Daily PM 2.5 samples were collected at an urban site in Guangzhou in 2014 and at a suburban site in Zhuhai in 2014-2015. Samples were subject to chemical analysis for various chemical components including organic carbon (OC), element carbon (EC), major water-soluble inorganic ions, and trace elements. The annual average PM 2.5 mass concentration was 48±22μgm -3 and 45±25μgm -3 in Guangzhou and Zhuhai, respectively, with the highest seasonal average concentration in winter and the lowest in summer at both sites. Regional transport of pollutants accompanied with different air mass origins arriving at the two sites and pollution sources in between the two cities caused larger seasonal variations in Zhuhai (>a factor of 3.5) than in Guangzhou (17% of PM 2.5 mass concentrations. Copyright © 2016 Elsevier B.V. All rights reserved.

Concentrations, sources and geochemistry of airborne particulate matter at a major European airport.

PubMed

Amato, Fulvio; Moreno, Teresa; Pandolfi, Marco; Querol, Xavier; Alastuey, Andrés; Delgado, Ana; Pedrero, Manuel; Cots, Nuria

2010-04-01

Monitoring of aerosol particle concentrations (PM(10), PM(2.5), PM(1)) and chemical analysis (PM(10)) was undertaken at a major European airport (El Prat, Barcelona) for a whole month during autumn 2007. Concentrations of airborne PM at the airport were close to those at road traffic hotspots in the nearby Barcelona city, with means measuring 48 microg PM(10)/m(3), 21 microg PM(2.5)/m(3) and 17 microg PM(1)/m(3). Meteorological controls on PM at El Prat are identified as cleansing daytime sea breezes with abundant coarse salt particles, alternating with nocturnal land-sourced winds which channel air polluted by industry and traffic (PM(1)/PM(10) ratios > 0.5) SE down the Llobregat Valley. Chemical analyses of the PM(10) samples show that crustal PM is dominant (38% of PM(10)), followed by total carbon (OC + EC, 25%), secondary inorganic aerosols (SIA, 20%), and sea salt (6%). Local construction work for a new airport terminal was an important contributor to PM(10) crustal levels. Source apportionment modelling PCA-MLRA identifies five factors: industrial/traffic, crustal, sea salt, SIA, and K(+) likely derived from agricultural biomass burning. Whereas most of the atmospheric contamination concerning ambient air PM(10) levels at El Prat is not attributable directly to aircraft movement, levels of carbon are unusually high (especially organic carbon), as are metals possibly sourced from tyre detritus/smoke in runway dust (Ba, Zn, Mo) and from brake dust in ambient PM(10) (Cu, Sb), especially when the airport is at its most busy. We identify microflakes of aluminous alloys in ambient PM(10) filters derived from corroded fuselage and wings as an unequivocal and highly distinctive tracer for aircraft movement.

Source apportionments of PM2.5 organic carbon during the elevated pollution episodes in the Ordos region, Inner Mongolia, China.

PubMed

Khuzestani, Reza Bashiri; Schauer, James J; Shang, Jing; Cai, Tianqi; Fang, Dongqing; Wei, Yongjie; Zhang, Lulu; Zhang, Yuanxun

2018-05-01

The Ordos region in the southwestern part of Inner Mongolia experiences frequent PM concentrations in excess of the national PM 2.5 air quality standards. In order to determine the key sources of PM 2.5 contributing to these pollution episodes, the main sources of PM 2.5 OC during elevated PM episodes in the Inner Mongolia were analyzed and compared with non-polluted days. This will provide insight to the main sources of particulate matter pollution during the high-pollution episodes and the effective seasonal strategies to control sources of particulate matter during months and with the highest PM concentrations that need to be controlled. The PMF source contributions to OC demonstrated that the industrial/coal combustion (4762.77 ± 1061.54 versus 2726.49 ± 469.75 ng/m 3 ; p < 0.001) and mobile source factors (4651.14 ± 681.82 versus 2605.55 ± 276.50 ng/m 3 ; p value < 0.001) showed greater contributions to the elevated concentrations during the episode. The spatial analysis of secondary organic carbon (SOC) factors, regional biomass burning, and biogenic sources did not show significant difference in the pollution episodes and the non-polluted months. In addition, the bivariate polar plots and CWT maps of the industrial/coal combustion and mobile illustrated a regional long-range transport patterns from the external sources to the study area, however, adjacent areas were mostly controlling the contributions of these factors during the PM elevated episodes. The SOC sources, regional biomass burning, and biogenic sources illustrated a regional long-range transport with similar locations found during the elevated pollution episodes compared to the normal situations.

Chemical characterization and source apportionment of submicron aerosols measured in Senegal during the 2015 SHADOW campaign

NASA Astrophysics Data System (ADS)

Rivellini, Laura-Hélèna; Chiapello, Isabelle; Tison, Emmanuel; Fourmentin, Marc; Féron, Anaïs; Diallo, Aboubacry; N'Diaye, Thierno; Goloub, Philippe; Canonaco, Francesco; Prévôt, André Stephan Henry; Riffault, Véronique

2017-09-01

The present study offers the first chemical characterization of the submicron (PM1) fraction in western Africa at a high time resolution, thanks to collocated measurements of nonrefractory (NR) species with an Aerosol Chemical Speciation Monitor (ACSM), black carbon and iron concentrations derived from absorption coefficient measurements with a 7-wavelength Aethalometer, and total PM1 determined by a TEOM-FDMS (tapered element oscillating microbalance-filtered dynamic measurement system) for mass closure. The field campaign was carried out over 3 months (March to June 2015) as part of the SHADOW (SaHAran Dust Over West Africa) project at a coastal site located in the outskirts of the city of Mbour, Senegal. With an averaged mass concentration of 5.4 µg m-3, levels of NR PM1 in Mbour were 3 to 10 times lower than those generally measured in urban and suburban polluted environments. Nonetheless the first half of the observation period was marked by intense but short pollution events (NR PM1 concentrations higher than 15 µg m-3), sea breeze phenomena and Saharan desert dust outbreaks (PM10 up to 900 µg m-3). During the second half of the campaign, the sampling site was mainly under the influence of marine air masses. The air masses on days under continental and sea breeze influences were dominated by organics (36-40 %), whereas sulfate particles were predominant (40 %) for days under oceanic influence. Overall, measurements showed that about three-quarters of the total PM1 were explained by NR PM1, BC (black carbon) and Fe (a proxy for dust) concentrations, leaving approximately one-quarter for other refractory species. A mean value of 4.6 % for the Fe / PM1 ratio was obtained. Source apportionment of the organic fraction, using positive matrix factorization (PMF), highlighted the impact of local combustion sources, such as traffic and residential activities, which contribute on average to 52 % of the total organic fraction. A new organic aerosol (OA) source, representing on average 3 % of the total OA fraction, showed similar variation to nonrefractory particulate chloride. Its rose plot and daily pattern pointed to local combustion processes, i.e., two open waste-burning areas located about 6 and 11 km away from the receptor site and to a lesser extent a traditional fish-smoking location. The remaining fraction was identified as oxygenated organic aerosols (OOA), a factor that prevailed regardless of the day type (45 %) and was representative of regional (approximately three-quarters) but also local (approximately one-quarter) sources due to enhanced photochemical processes.

Source apportionment of fine particulate matter in China in 2013 using a source-oriented chemical transport model.

PubMed

Shi, Zhihao; Li, Jingyi; Huang, Lin; Wang, Peng; Wu, Li; Ying, Qi; Zhang, Hongliang; Lu, Li; Liu, Xuejun; Liao, Hong; Hu, Jianlin

2017-12-01

China has been suffering high levels of fine particulate matter (PM 2.5 ). Designing effective PM 2.5 control strategies requires information about the contributions of different sources. In this study, a source-oriented Community Multiscale Air Quality (CMAQ) model was applied to quantitatively estimate the contributions of different source sectors to PM 2.5 in China. Emissions of primary PM 2.5 and gas pollutants of SO 2 , NO x , and NH 3 , which are precursors of particulate sulfate, nitrate, and ammonium (SNA, major PM 2.5 components in China), from eight source categories (power plants, residential sources, industries, transportation, open burning, sea salt, windblown dust and agriculture) were separately tracked to determine their contributions to PM 2.5 in 2013. Industrial sector is the largest source of SNA in Beijing, Xi'an and Chongqing, followed by agriculture and power plants. Residential emissions are also important sources of SNA, especially in winter when severe pollution events often occur. Nationally, the contributions of different source sectors to annual total PM 2.5 from high to low are industries, residential sources, agriculture, power plants, transportation, windblown dust, open burning and sea salt. Provincially, residential sources and industries are the major anthropogenic sources of primary PM 2.5 , while industries, agriculture, power plants and transportation are important for SNA in most provinces. For total PM 2.5 , residential and industrial emissions are the top two sources, with a combined contribution of 40-50% in most provinces. The contributions of power plants and agriculture to total PM 2.5 are about 10%, respectively. Secondary organic aerosol accounts for about 10% of annual PM 2.5 in most provinces, with higher contributions in southern provinces such as Yunnan (26%), Hainan (25%) and Taiwan (21%). Windblown dust is an important source in western provinces such as Xizang (55% of total PM 2.5 ), Qinghai (74%), Xinjiang (59%). The large variation in sources of PM 2.5 across China suggests that PM 2.5 mitigation programs should be designed separately for different regions/provinces. Copyright © 2017 Elsevier B.V. All rights reserved.

Personal exposure to particulate PAHs and anthraquinone and oxidative DNA damages in humans.

PubMed

Wei, Yongjie; Han, In-Kyu; Hu, Min; Shao, Min; Zhang, Junfeng Jim; Tang, Xiaoyan

2010-11-01

Recent studies suggest that DNA oxidative damage be related to the chemical constituents of ambient particles. The purpose of this study was to examine whether particulate polycyclic aromatic hydrocarbons (PAHs) and quinone-structure chemicals increase body burden of oxidative stress in human exposed to heavy traffic volume. We recruited two nonsmoking security guards who worked at a university campus gate near a heavily trafficked road. Each subject wore a personal air sampler for 24h per day to estimate exposures to 24 PAHs and anthraquinone (AnQ) in PM(2.5). Daily pre- and post-work shift spot urines were collected for 29d from each subject. Urine samples were analyzed for 8-hydroxy-2'-deoxyguanosine (8-OHdG). Additionally, using 19 organic tracers other than 24 PAHs and AnQ, a receptor source apportionment model of chemical mass balance was applied to determine the contributions of sources on the PM: gasoline vehicle, diesel vehicle, coal burning, vegetable debris, cooking, natural gas and biomass burning. The relationship among urinary 8-OHdG, individual PAH, and AnQ was demonstrated as follows: the average urinary concentration of 8-OHdG was increased more than three times after 8-h work-shift than those before the work shift. All the 24 PAH and AnQ levels were positively and significantly associated with the post-work urinary 8-OHdG. The results from source apportionment suggest vehicular emission to be the dominant source of personal exposure to PM(2.5). Our finding indicates that personal air exposures to 24 individual PAHs and AnQ originating from traffic emissions are important in increasing oxidative burdens in human body. Copyright © 2010 Elsevier Ltd. All rights reserved.

Size distribution, directional source contributions and pollution status of PM from Chengdu, China during a long-term sampling campaign.

PubMed

Shi, Guo-Liang; Tian, Ying-Ze; Ma, Tong; Song, Dan-Lin; Zhou, Lai-Dong; Han, Bo; Feng, Yin-Chang; Russell, Armistead G

2017-06-01

Long-term and synchronous monitoring of PM 10 and PM 2.5 was conducted in Chengdu in China from 2007 to 2013. The levels, variations, compositions and size distributions were investigated. The sources were quantified by two-way and three-way receptor models (PMF2, ME2-2way and ME2-3way). Consistent results were found: the primary source categories contributed 63.4% (PMF2), 64.8% (ME2-2way) and 66.8% (ME2-3way) to PM 10 , and contributed 60.9% (PMF2), 65.5% (ME2-2way) and 61.0% (ME2-3way) to PM 2.5 . Secondary sources contributed 31.8% (PMF2), 32.9% (ME2-2way) and 31.7% (ME2-3way) to PM 10 , and 35.0% (PMF2), 33.8% (ME2-2way) and 36.0% (ME2-3way) to PM 2.5 . The size distribution of source categories was estimated better by the ME2-3way method. The three-way model can simultaneously consider chemical species, temporal variability and PM sizes, while a two-way model independently computes datasets of different sizes. A method called source directional apportionment (SDA) was employed to quantify the contributions from various directions for each source category. Crustal dust from east-north-east (ENE) contributed the highest to both PM 10 (12.7%) and PM 2.5 (9.7%) in Chengdu, followed by the crustal dust from south-east (SE) for PM 10 (9.8%) and secondary nitrate & secondary organic carbon from ENE for PM 2.5 (9.6%). Source contributions from different directions are associated with meteorological conditions, source locations and emission patterns during the sampling period. These findings and methods provide useful tools to better understand PM pollution status and to develop effective pollution control strategies. Copyright © 2016. Published by Elsevier B.V.

Source apportionment and health risk assessment among specific age groups during haze and non-haze episodes in Kuala Lumpur, Malaysia.

PubMed

Sulong, Nor Azura; Latif, Mohd Talib; Khan, Md Firoz; Amil, Norhaniza; Ashfold, Matthew J; Wahab, Muhammad Ikram Abdul; Chan, Kok Meng; Sahani, Mazrura

2017-12-01

This study aims to determine PM 2.5 concentrations and their composition during haze and non-haze episodes in Kuala Lumpur. In order to investigate the origin of the measured air masses, the Numerical Atmospheric-dispersion Modelling Environment (NAME) and Global Fire Assimilation System (GFAS) were applied. Source apportionment of PM 2.5 was determined using Positive Matrix Factorization (PMF). The carcinogenic and non-carcinogenic health risks were estimated using the United State Environmental Protection Agency (USEPA) method. PM 2.5 samples were collected from the centre of the city using a high-volume air sampler (HVS). The results showed that the mean PM 2.5 concentrations collected during pre-haze, haze and post-haze periods were 24.5±12.0μgm -3 , 72.3±38.0μgm -3 and 14.3±3.58μgm -3 , respectively. The highest concentration of PM 2.5 during haze episode was five times higher than World Health Organisation (WHO) guidelines. Inorganic compositions of PM 2.5 , including trace elements and water soluble ions were determined using inductively coupled plasma-mass spectrometry (ICP-MS) and ion chromatography (IC), respectively. The major trace elements identified were K, Al, Ca, Mg and Fe which accounted for approximately 93%, 91% and 92% of the overall metals' portions recorded during pre-haze, haze and post-haze periods, respectively. For water-soluble ions, secondary inorganic aerosols (SO 4 2- , NO 3 - and NH 4 + ) contributed around 12%, 43% and 16% of the overall PM 2.5 mass during pre-haze, haze and post-haze periods, respectively. During haze periods, the predominant source identified using PMF was secondary inorganic aerosol (SIA) and biomass burning where the NAME simulations indicate the importance of fires in Sumatra, Indonesia. The main source during pre-haze and post-haze were mix SIA and road dust as well as mineral dust, respectively. The highest non-carcinogenic health risk during haze episode was estimated among the infant group (HI=1.06) while the highest carcinogenic health risk was estimated among the adult group (2.27×10 -5 ). Copyright © 2017 Elsevier B.V. All rights reserved.

Carbonaceous species in PM2.5 and PM10 in urban area of Zhengzhou in China: Seasonal variations and source apportionment

NASA Astrophysics Data System (ADS)

Wang, Qun; Jiang, Nan; Yin, Shasha; Li, Xiao; Yu, Fei; Guo, Yue; Zhang, Ruiqin

2017-07-01

PM2.5 and PM10 samples were simultaneously collected in an urban site in Zhengzhou, China from October 2014 to July 2015 representing the four seasons. Organic carbon (OC), elemental carbon (EC), and non-polar organic compounds including n-alkanes (C8-C40) and polycyclic aromatic hydrocarbons (PAHs) were quantified. The characteristics of their concentrations, seasonal variations, and sources of n-alkanes and PAHs were investigated. Diagnostic ratios and positive matrix factorization (PMF) were used to characterize carbonaceous species, identify their possible sources, and apportion the contributions from each possible source. The concentrations of the components exhibited distinct seasonal variation, that is, the concentrations are high in winter and low in summer. This finding could be associated with increase in air pollutant emissions during heating season and stable weather condition. The estimated total carbonaceous aerosol accounts for 32% of PM2.5 and 30% of PM10. Hence, carbonaceous compounds were the major components of particulate matter in the study area. Moreover, OC, EC, PAHs, and n-alkanes preferentially accumulated into fine particles. The carbonaceous components exhibited high correlation in PM2.5 and PM10, thereby indicating that their sources were similar. The PMF results revealed that the main sources of PAHs were coal combustion (40%) and motor vehicles (29%); n-alkanes were mainly from burning of fossil fuel (48%). These sources were consistent with the diagnostic ratios obtained. This study provides guidance for improving air quality and reducing human exposure to toxic air pollutants.

Quantifying impacts on air quality of vehicular emissions in Sao Paulo and Rio de Janeiro

NASA Astrophysics Data System (ADS)

Artaxo, Paulo; Ferreira de Brito, Joel; Godoy, José Marcus; Luiza Godoy, Maria; Junior, Djacinto

2016-04-01

Vehicular emissions in megacities such as Sao Paulo and Rio de Janeiro are increasingly becoming a global issue. The São Paulo Metropolitan Area (SPMA), located in Southeast of Brazil, is a megacity with a population of 18 million people, with 7 million cars and large-scale industrial emissions. Rio de Janeiro is also a large city with different meteorology than São Paulo. All cars in Brazil runs gasohol, with 23% ethanol in gasoline, and for the last 10 years, flex cars that can run on gasohol, ethanol or any mixture dominate the market. Overall ethanol accounts for about 30-40% of fuel burned in both cities. To improve the understanding of vehicular emission impacts on aerosol composition and life cycle in these two large megacities a source apportionment study, combining online and offline measurements, was performed. Aerosols were collected for one year to capture seasonal variability at 4 sites in each city, with inorganic and organic aerosol component being sampled. Organic and elemental carbon were measured using a Sunset Laboratory Dual Optics (transmission and reflectance) Carbon Analyzer and about 22 trace elements has been measured using polarized X-Ray Fluorescence (XRF). Aerosol mass and black carbon were also measured, as well as trace gases to help in aerosol source apportionment. In Sao Paulo, the average PM2.5 mass concentration obtained varied from 9.6 to 12.2 μg m-3 for the several sites, and similar concentrations were measured in Rio de Janeiro. At all sites, organic matter (OM) has dominated fine mode aerosol concentration with 42 to 60% of the aerosol mass. EC accounted for 21 to 31% of fine mode aerosol mass concentration. Sulfate accounted for 21 to 26% of PM2.5 for the sites. Aerosol source apportionment was done with receptor analysis and integration with online data such as PTR-MS, Aethalometers, Nephelometers and ACSM helped to apportion vehicular emissions. For the 8 sites operated in Sao Paulo and Rio de Janeiro, vehicular emissions accounts for about 63% of PM2.5. Results are very similar for the different sites and cities.

Chemical characterization of atmospheric particles and source apportionment in the vicinity of a steelmaking industry.

PubMed

Almeida, S M; Lage, J; Fernández, B; Garcia, S; Reis, M A; Chaves, P C

2015-07-15

The objective of this work was to provide a chemical characterization of atmospheric particles collected in the vicinity of a steelmaking industry and to identify the sources that affect PM10 levels. A total of 94 PM samples were collected in two sampling campaigns that occurred in February and June/July of 2011. PM2.5 and PM2.5-10 were analyzed for a total of 22 elements by Instrumental Neutron Activation Analysis and Particle Induced X-ray Emission. The concentrations of water soluble ions in PM10 were measured by Ion Chromatography and Indophenol-Blue Spectrophotometry. Positive Matrix Factorization receptor model was used to identify sources of particulate matter and to determine their mass contribution to PM10. Seven main groups of sources were identified: marine aerosol identified by Na and Cl (22%), steelmaking and sinter plant represented by As, Cr, Cu, Fe, Ni, Mn, Pb, Sb and Zn (11%), sinter plant stack identified by NH4(+), K and Pb (12%), an unidentified Br source (1.8%), secondary aerosol from coke making and blast furnace (19%), fugitive emissions from the handling of raw material, sinter plant and vehicles dust resuspension identified by Al, Ca, La, Si, Ti and V (14%) and sinter plant and blast furnace associated essentially with Fe and Mn (21%). Copyright © 2015 Elsevier B.V. All rights reserved.

PM10 source apportionment in a Swiss Alpine valley impacted by highway traffic.

PubMed

Ducret-Stich, Regina E; Tsai, Ming-Yi; Thimmaiah, Devraj; Künzli, Nino; Hopke, Philip K; Phuleria, Harish C

2013-09-01

Although trans-Alpine highway traffic exhaust is one of the major sources of air pollution along the highway valleys of the Alpine regions, little is known about its contribution to residential exposure and impact on respiratory health. In this paper, source-specific contributions to particulate matter with an aerodynamic diameter < 10 μm (PM10) and their spatio-temporal distribution were determined for later use in a pediatric asthma panel study in an Alpine village. PM10 sources were identified by positive matrix factorization using chemical trace elements, elemental, and organic carbon from daily PM10 filters collected between November 2007 and June 2009 at seven locations within the village. Of the nine sources identified, four were directly road traffic-related: traffic exhaust, road dust, tire and brake wear, and road salt contributing 16 %, 8 %, 1 %, and 2 % to annual PM10 concentrations, respectively. They showed a clear dependence with distance to highway. Additional contributions were identified from secondary particles (27 %), biomass burning (18 %), railway (11 %), and mineral dust including a local construction site (13 %). Comparing these source contributions with known source-specific biomarkers (e.g., levoglucosan, nitro-polycyclic aromatic hydrocarbons) showed high agreement with biomass burning, moderate with secondary particles (in winter), and lowest agreement with traffic exhaust.

PM₁₀ and PM₂.₅ sources at an insular location in the western Mediterranean by using source apportionment techniques.

PubMed

Pey, Jorge; Alastuey, Andrés; Querol, Xavier

2013-07-01

PM₁₀ and PM₂.₅ chemical composition has been determined at a suburban insular site in the Balearic Islands (Spain) during almost one and a half year. As a result, 200 samples with more than 50 chemical parameters analyzed have been obtained. The whole database has been analyzed by two receptor modelling techniques (Principal Component Analysis and Positive Matrix Factorisation) in order to identify the main PM sources. After that, regression analyses with respect to the PM mass concentrations were conducted to quantify the daily contributions of each source. Four common sources were identified by both receptor models: secondary nitrate coupled with vehicular emissions, secondary sulphate influenced by fuel-oil combustion, aged marine aerosols and mineral dust. In addition, PCA isolated harbour emissions and a mixed anthropogenic factor containing industrial emissions; whereas PMF isolated an additional mineral factor interpreted as road dust+harbour emissions, and a vehicular abrasion products factor. The use of both methodologies appeared complementary. Nevertheless, PMF sources by themselves were better differentiated. Besides these receptor models, a specific methodology to quantify African dust was also applied. The combination of these three source apportionment tools allowed the identification of 8 sources, being 4 of them mineral (African, regional, urban and harbour dusts). As a summary, 29% of PM₁₀ was attributed to natural sources (African dust, regional dust and sea spray), whereas the proportion diminished to 11% in PM₂.₅. Furthermore, the secondary sulphate source, which accounted for about 22 and 32% of PM₁₀ and PM₂.₅, is strongly linked to the aged polluted air masses residing over the western Mediterranean in the warm period. Copyright © 2013 Elsevier B.V. All rights reserved.

Source apportionment of fine particulate matter measured in an industrialized coastal urban area of South Texas

NASA Astrophysics Data System (ADS)

Karnae, Saritha; John, Kuruvilla

2011-07-01

Corpus Christi is a growing industrialized urban airshed in South Texas impacted by local emissions and regional transport of fine particulate matter (PM 2.5). Positive matrix factorization (PMF2) technique was used to evaluate particulate matter pollution in the urban airshed by estimating the types of sources and its corresponding mass contributions affecting the measured ambient PM 2.5 levels. Fine particulate matter concentrations by species measured during July 2003 through December 2008 at a PM 2.5 speciation site were used in this study. PMF2 identified eight source categories, of which secondary sulfates were the dominant source category accounting for 30.4% of the apportioned mass. The other sources identified included aged sea salt (18.5%), biomass burns (12.7%), crustal dust (10.1%), traffic (9.7%), fresh sea salt (8.1%), industrial sources (6%), and a co-mingled source of oil combustion & diesel emissions (4.6%). The apportioned PM mass showed distinct seasonal variability between source categories. The PM levels in Corpus Christi were affected by biomass burns in Mexico and Central America during April and May, sub-Saharan dust storms from Africa during the summer months, and a continental haze episode during August and September with significant transport from the highly industrialized areas of Texas and the neighboring states. Potential source contribution function (PSCF) analysis was performed and it identified source regions and the influence of long-range transport of fine particulate matter affecting this urban area.

Apportionment of sources of fine and coarse particles in four major Australian cities by positive matrix factorisation

NASA Astrophysics Data System (ADS)

Chan, Yiu-Chung; Cohen, David D.; Hawas, Olga; Stelcer, Eduard; Simpson, Rod; Denison, Lyn; Wong, Neil; Hodge, Mary; Comino, Eva; Carswell, Stewart

In this study, 437 days of 6-daily, 24-h samples of PM 2.5, PM 2.5-10 and PM 10 were collected over a 12-month period during 2003-2004 in Melbourne, Sydney, Brisbane and Adelaide. The elemental, ionic and polycyclic aromatic hydrocarbon composition of the particles were determined. Source apportionment was carried out by using the positive matrix factorisation software (PMF2). Eight factors were identified for the fine particle samples including 'motor vehicles', 'industry', 'other combustion sources', 'ammonium sulphates', 'nitrates', 'marine aerosols', 'chloride depleted marine aerosols' and 'crustal/soil dust'. On average combustion sources, secondary nitrates/sulphates and natural origin dust contributed about 46%, 25% and 26% of the mass of the fine particle samples, respectively. 'Crustal/soil dust', 'marine aerosols', 'nitrates' and 'road side dust' were the four factors identified for the coarse particle samples. On average natural origin dust contributed about 76% of the mass of the coarse particle samples. The contributions of the sources to the sample mass basically reflect the emission source characteristics of the sites. Secondary sulphates and nitrates were found to spread out evenly within each city. The average contribution of secondary nitrates to fine particles was found to be rather uniform in different seasons, rather than higher in winter as found in other studies. This could be due to the low humidity conditions in winter in most of the Australian cities which made the partitioning of the particle phase less favourable in the NH 4NO 3 equilibrium system. A linear relationship was found between the average contribution of marine aerosols and the distance of the site from the bay side. Wind erosion was found associated with higher contribution of crustal dust on average and episodes of elevated concentration of coarse particles in spring and summer.

Characterization of PM2.5 in Guangzhou, China: uses of organic markers for supporting source apportionment.

PubMed

Wang, Jingzhi; Ho, Steven Sai Hang; Ma, Shexia; Cao, Junji; Dai, Wenting; Liu, Suixin; Shen, Zhenxing; Huang, Rujin; Wang, Gehui; Han, Yongming

2016-04-15

Organic carbon (OC), elemental carbon (EC), and non-polar organic compounds including n-alkanes (n-C14-n-C40), polycyclic aromatic hydrocarbons (PAHs), phthalate esters (PAEs) and hopanes were quantified in fine particulate (PM2.5), which were collected in urban area of Guangzhou, China in winter and summer in 2012/2013. The pollutants levels were well comparable with the data obtained in previous studies in Pearl River Delta (PRD) region but much lower than most northern Chinese megacities. The contribution of EC to PM2.5 and OC/EC ratio suggest that the pollution sources were relatively consistent in GZ between the two seasons. Benzo[a]pyrene (BaP) was the most abundant PAHs, which were 4.9 and 1.0ng/m(3) on average, accounting for 10.7% and 9.1% to the total quantified PAHs in winter and summer, respectively. The total concentrations of PAEs ranged from 289.1 to 2435ng/m(3) and from 102.4 to 1437ng/m(3), respectively, in winter and summer. Di-n-butyl phthalate (DBP) was the most dominant PAEs. The ambient levels of PAEs could be partly attributed to the widespread uses of the household products, municipal garbage compressing, sewage, and external painting material on the building. Source apportionment for OC with chemical mass balance (CMB) model demonstrated coal combustion, vehicle emission, cooking, and secondary organic compounds (SOC) formation were the four major pollution sources. Both of the indices of n-alkanes and diagnostic PAHs ratios support that anthropogenic sources such as vehicle emission and coal combustion were the significant pollution sources with some extents from epicuticular waxes by terrestrial plants. The ratio of hopanes to EC proved the influences from vehicle emission, and displayed a certain degree of the air aging in the Guangzhou ambient air. Copyright © 2016 Elsevier B.V. All rights reserved.

Emission characteristics and chemical components of size-segregated particulate matter in iron and steel industry

NASA Astrophysics Data System (ADS)

Jia, Jia; Cheng, Shuiyuan; Yao, Sen; Xu, Tiebing; Zhang, Tingting; Ma, Yuetao; Wang, Hongliang; Duan, Wenjiao

2018-06-01

As one of the highest energy consumption and pollution industries, the iron and steel industry is regarded as a most important source of particulate matter emission. In this study, chemical components of size-segregated particulate matters (PM) emitted from different manufacturing units in iron and steel industry were sampled by a comprehensive sampling system. Results showed that the average particle mass concentration was highest in sintering process, followed by puddling, steelmaking and then rolling processes. PM samples were divided into eight size fractions for testing the chemical components, SO42- and NH4+ distributed more into fine particles while most of the Ca2+ was concentrated in coarse particles, the size distribution of mineral elements depended on the raw materials applied. Moreover, local database with PM chemical source profiles of iron and steel industry were built and applied in CMAQ modeling for simulating SO42- and NO3- concentration, results showed that the accuracy of model simulation improved with local chemical source profiles compared to the SPECIATE database. The results gained from this study are expected to be helpful to understand the components of PM in iron and steel industry and contribute to the source apportionment researches.

Contribution of regional-scale fire events to ozone and PM2.5 air quality estimated by photochemical modeling approaches

NASA Astrophysics Data System (ADS)

Baker, K. R.; Woody, M. C.; Tonnesen, G. S.; Hutzell, W.; Pye, H. O. T.; Beaver, M. R.; Pouliot, G.; Pierce, T.

2016-09-01

Two specific fires from 2011 are tracked for local to regional scale contribution to ozone (O3) and fine particulate matter (PM2.5) using a freely available regulatory modeling system that includes the BlueSky wildland fire emissions tool, Spare Matrix Operator Kernel Emissions (SMOKE) model, Weather and Research Forecasting (WRF) meteorological model, and Community Multiscale Air Quality (CMAQ) photochemical grid model. The modeling system was applied to track the contribution from a wildfire (Wallow) and prescribed fire (Flint Hills) using both source sensitivity and source apportionment approaches. The model estimated fire contribution to primary and secondary pollutants are comparable using source sensitivity (brute-force zero out) and source apportionment (Integrated Source Apportionment Method) approaches. Model estimated O3 enhancement relative to CO is similar to values reported in literature indicating the modeling system captures the range of O3 inhibition possible near fires and O3 production both near the fire and downwind. O3 and peroxyacetyl nitrate (PAN) are formed in the fire plume and transported downwind along with highly reactive VOC species such as formaldehyde and acetaldehyde that are both emitted by the fire and rapidly produced in the fire plume by VOC oxidation reactions. PAN and aldehydes contribute to continued downwind O3 production. The transport and thermal decomposition of PAN to nitrogen oxides (NOX) enables O3 production in areas limited by NOX availability and the photolysis of aldehydes to produce free radicals (HOX) causes increased O3 production in NOX rich areas. The modeling system tends to overestimate hourly surface O3 at routine rural monitors in close proximity to the fires when the model predicts elevated fire impacts on O3 and Hazard Mapping System (HMS) data indicates possible fire impact. A sensitivity simulation in which solar radiation and photolysis rates were more aggressively attenuated by aerosol in the plume reduced model O3 but does not eliminate this bias. A comparison of model predicted daily average speciated PM2.5 at surface rural routine network sites when the model predicts fire impacts from either of these fires shows a tendency toward overestimation of PM2.5 organic aerosol in close proximity to these fires. The standard version of the CMAQ treats primarily emitted organic aerosol as non-volatile. An alternative approach for treating organic aerosol as semi-volatile resulted in lower PM2.5 organic aerosol from these fires but does not eliminate the bias. Future work should focus on modeling specific fire events that are well characterized in terms of size, emissions, and have extensive measurements taken near the fire and downwind to better constrain model representation of important physical and chemical processes (e.g. aerosol photolysis attenuation and organic aerosol treatment) related to wild and prescribed fires.

Coarse and fine aerosol source apportionment in Rio de Janeiro, Brazil

NASA Astrophysics Data System (ADS)

Godoy, Maria Luiza D. P.; Godoy, José Marcus; Roldão, Luiz Alfredo; Soluri, Daniela S.; Donagemma, Raquel A.

The metropolitan area of Rio de Janeiro is one of the twenty biggest urban agglomerations in the world, with 11 million inhabitants in the metropolitan area, and has a high population density, with 1700 hab. km -2. For this aerosol source apportionment study, the atmospheric aerosol sampling was performed at ten sites distributed in different locations of the metropolitan area from September/2003 to December/2005, with sampling during 24 h on a weekly basis. Stacked filter units (SFU) were used to collect fine and coarse aerosol particles with a flow rate of 17 L min -1. In both size fractions trace elements were analyzed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) as well as water-soluble species by Ion-Chromatography (IC). Also gravimetric analysis and reflectance measurements provided aerosol mass and black carbon concentrations. Very good detection limits for up to 42 species were obtained. Mean annual PM 10 mass concentration ranged from 20 to 37 μg m -3, values that are within the Brazilian air quality standards. Receptor models such as principal factor analysis, cluster analysis and absolute principal factor analysis were applied in order to identify and quantify the aerosol sources. For fine and coarse modes, circa of 100% of the measured mass was quantitatively apportioned to relatively few identified aerosol sources. A very similar and consistent source apportionment was obtained for both fine and coarse modes for all 10 sampling sites. Soil dust is an important component, accounting for 22-72% and for 25-48% of the coarse and fine mass respectively. On the other hand, anthropogenic sources as vehicle traffic and oil combustion represent a relatively high contribution (52-75%) of the fine aerosol mass. The joint use of ICP-MS and IC analysis of species in aerosols has proven to be reliable and feasible for the analysis of large amount of samples, and the coupling with receptor models provided an excellent method for quantitative aerosol source apportionment in large urban areas.

Aerosol composition and source apportionment in Santiago de Chile

NASA Astrophysics Data System (ADS)

Artaxo, Paulo; Oyola, Pedro; Martinez, Roberto

1999-04-01

Santiago de Chile, São Paulo and Mexico City are Latin American urban areas that suffer from heavy air pollution. In order to study air pollution in Santiago area, an aerosol source apportionment study was designed to measure ambient aerosol composition and size distribution for two downtown sampling sites in Santiago. The aerosol monitoring stations were operated in Gotuzo and Las Condes during July and August 1996. The study employed stacked filter units (SFU) for aerosol sampling, collecting fine mode aerosol (dp<2 μm) and coarse mode aerosol (2

High-resolution sampling and analysis of ambient particulate matter in the Pearl River Delta region of southern China: source apportionment and health risk implications

NASA Astrophysics Data System (ADS)

Zhou, Shengzhen; Davy, Perry K.; Huang, Minjuan; Duan, Jingbo; Wang, Xuemei; Fan, Qi; Chang, Ming; Liu, Yiming; Chen, Weihua; Xie, Shanju; Ancelet, Travis; Trompetter, William J.

2018-02-01

Hazardous air pollutants, such as trace elements in particulate matter (PM), are known or highly suspected to cause detrimental effects on human health. To understand the sources and associated risks of PM to human health, hourly time-integrated major trace elements in size-segregated coarse (PM2.5-10) and fine (PM2.5) particulate matter were collected at the industrial city of Foshan in the Pearl River Delta region, China. Receptor modeling of the data set by positive matrix factorization (PMF) was used to identify six sources contributing to PM2.5 and PM10 concentrations at the site. Dominant sources included industrial coal combustion, secondary inorganic aerosol, motor vehicles and construction dust along with two intermittent sources (biomass combustion and marine aerosol). The biomass combustion source was found to be a significant contributor to peak PM2.5 episodes along with motor vehicles and industrial coal combustion. Conditional probability function (CPF) analysis was applied to estimate the source locations using the PMF-resolved source contribution coupled with the surface wind direction data. Health exposure risk of hazardous trace elements (Pb, As, Si, Cr, Mn and Ni) and source-specific values were estimated. The total hazard quotient (HQ) of PM2.5 was 2.09, higher than the acceptable limit (HQ = 1). The total carcinogenic risk (CR) was 3.37 × 10-3 for PM2.5, which was 3 times higher than the least stringent limit (1.0 × 10-4). Among the selected trace elements, As and Pb posed the highest non-carcinogenic and carcinogenic risks to human health, respectively. In addition, our results show that the industrial coal combustion source is the dominant non-carcinogenic and carcinogenic risk contributor, highlighting the need for stringent control of this source. This study provides new insight for policy makers to prioritize sources in air quality management and health risk reduction.

Source-specific fine particulate air pollution and systemic inflammation in ischaemic heart disease patients

PubMed Central

Siponen, Taina; Yli-Tuomi, Tarja; Aurela, Minna; Dufva, Hilkka; Hillamo, Risto; Hirvonen, Maija-Riitta; Huttunen, Kati; Pekkanen, Juha; Pennanen, Arto; Salonen, Iiris; Tiittanen, Pekka; Salonen, Raimo O; Lanki, Timo

2015-01-01

Objective To compare short-term effects of fine particles (PM2.5; aerodynamic diameter <2.5 µm) from different sources on the blood levels of markers of systemic inflammation. Methods We followed a panel of 52 ischaemic heart disease patients from 15 November 2005 to 21 April 2006 with clinic visits in every second week in the city of Kotka, Finland, and determined nine inflammatory markers from blood samples. In addition, we monitored outdoor air pollution at a fixed site during the study period and conducted a source apportionment of PM2.5 using the Environmental Protection Agency's model EPA PMF 3.0. We then analysed associations between levels of source-specific PM2.5 and markers of systemic inflammation using linear mixed models. Results We identified five source categories: regional and long-range transport (LRT), traffic, biomass combustion, sea salt, and pulp industry. We found most evidence for the relation of air pollution and inflammation in LRT, traffic and biomass combustion; the most relevant inflammation markers were C-reactive protein, interleukin-12 and myeloperoxidase. Sea salt was not positively associated with any of the inflammatory markers. Conclusions Results suggest that PM2.5 from several sources, such as biomass combustion and traffic, are promoters of systemic inflammation, a risk factor for cardiovascular diseases. PMID:25479755

Source apportion of atmospheric particulate matter: a joint Eulerian/Lagrangian approach.

PubMed

Riccio, A; Chianese, E; Agrillo, G; Esposito, C; Ferrara, L; Tirimberio, G

2014-12-01

PM2.5 samples were collected during an annual monitoring campaign (January 2012-January 2013) in the urban area of Naples, one of the major cities in Southern Italy. Samples were collected by means of a standard gravimetric sampler (Tecora Echo model) and characterized from a chemical point of view by ion chromatography. As a result, 143 samples together with their ionic composition have been collected. We extend traditional source apportionment techniques, usually based on multivariate factor analysis, interpreting the chemical analysis results within a Lagrangian framework. The Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HYSPLIT) model was used, providing linkages to the source regions in the upwind areas. Results were analyzed in order to quantify the relative weight of different source types/areas. Model results suggested that PM concentrations are strongly affected not only by local emissions but also by transboundary emissions, especially from the Eastern and Northern European countries and African Saharan dust episodes.

Spatial and temporal characteristics of PM2.5 and source apportionment in Wuhan

NASA Astrophysics Data System (ADS)

Hao, Hanzhou; Guo, Qianqian

2018-02-01

In order to study the pollution characteristics and sources of PM2.5, the PM2.5 in Wuhan atmosphere was sampled continuously. Inductively coupled plasma mass spectrometry (ICP-MS) were employed to measure Na, K, Mg, Ca, Al, Mn, Cu, Zn, As, Pb, Cr, Ni, Co, Cd, Fe, V, Ti, Hg, Si, while water soluble ions (Cl-, NO3-, SO4 2-) as well as carbonaceous mass (EC and OC) were analyzed using ion chromatograph(IC) and carbon analyzer, respectively. The results show: (1) In 2014 and 2015, Wuhan PM2.5 values were 81.4μg/m3and 69.2μg/m3 respectively far exceed the national standard level 2, i.e. annual average 35 μg/m3 in China, annual average limit 10 μg/m3 by the World Health Organization, the annual limit of 15 μg/m3 in the United States. (2) Taking Huaqiao and Qihao as research points, the Spring Festival effect of PM2.5 in Wuhan city is analyzed. It shows that the concentration of PM2.5 in 2014 and 2015 is before Spring Festival> during Spring Festival> after Spring Festival. As a backdrop, during the Spring Festival, Qihao PM2.5 concentration than Huaqiao average low 20 μg/m3. (3) The results of positive factor matrix factorization (PMF) analysis show that PM2.5 in Summer in Wuhan mainly comes from the automobile source, soil dust source, biomass combustion, industrial source, secondary aerosol source, combustion coal source, the contribution rate is 37.7%. 25%, 16.4%, 8.1%, 6.5%,6.4%, respectively.

Organic composition and source apportionment of fine aerosol at Monterrey, Mexico, based on organic markers

NASA Astrophysics Data System (ADS)

Mancilla, Y.; Mendoza, A.; Fraser, M. P.; Herckes, P.

2016-01-01

Primary emissions from anthropogenic and biogenic sources as well as secondary formation are responsible for the pollution levels of ambient air in major urban areas. These sources release fine particles into the air that negatively impact human health and the environment. Organic molecular markers, which are compounds that are unique to specific PM2.5 sources, can be utilized to identify the major emission sources in urban areas. In this study, 43 representative PM2.5 samples, for both daytime and nighttime periods, were built from individual samples collected in an urban site of the Monterrey metropolitan area (MMA) during the spring and fall of 2011 and 2012. The samples were analyzed for organic carbon, elemental carbon, and organic molecular markers. Several diagnostic tools were employed for the preliminary identification of emission sources. Organic compounds for eight compound classes were quantified. The n-alkanoic acids were the most abundant, followed by n-alkanes, wood smoke markers, and levoglucosan/alkenoic acids. Polycyclic aromatic hydrocarbons (PAHs) and hopanes were less abundant. The carbon preference index (0.7-2.6) for n-alkanes indicates a major contribution of anthropogenic and mixed sources during the fall and the spring, respectively. Hopanes levels confirmed the contribution from gasoline and diesel engines. In addition, the contribution of gasoline and diesel vehicle exhaust was confirmed and identified by the PAH concentrations in PM2.5. Diagnostic ratios of PAHs showed emissions from burning coal, wood, biomass, and other fossil fuels. The total PAHs and elemental carbon were correlated (r2 = 0.39-0.70) across the monitoring periods, reinforcing that motor vehicles are the major contributors of PAHs. Cholesterol levels remained constant during the spring and fall, showing evidence of the contribution of meat-cooking operations, while the isolated concentrations of levoglucosan suggested occasional biomass burning events. Finally, source attribution results obtained using the CMB (chemical mass balance) model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5, followed by meat-cooking operations with 31 % The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5). To our knowledge, this is only the second study to explore the organic composition and source apportionment of fine organic aerosol based on molecular markers in Mexico and the first for the MMA. Particularly molecular marker were quantified by solvent extraction with dichloromethane, derivatization, and gas chromatography with mass spectrometry (GC/MS).

Source apportionment of speciated PM2.5 and non-parametric regressions of PM2.5 and PM(coarse) mass concentrations from Denver and Greeley, Colorado, and construction and evaluation of dichotomous filter samplers

NASA Astrophysics Data System (ADS)

Piedrahita, Ricardo A.

The Denver Aerosol Sources and Health study (DASH) was a long-term study of the relationship between the variability in fine particulate mass and chemical constituents (PM2.5, particulate matter less than 2.5mum) and adverse health effects such as cardio-respiratory illnesses and mortality. Daily filter samples were chemically analyzed for multiple species. We present findings based on 2.8 years of DASH data, from 2003 to 2005. Multilinear Engine 2 (ME-2), a receptor-based source apportionment model was applied to the data to estimate source contributions to PM2.5 mass concentrations. This study relied on two different ME-2 models: (1) a 2-way model that closely reflects PMF-2; and (2) an enhanced model with meteorological data that used additional temporal and meteorological factors. The Coarse Rural Urban Sources and Health study (CRUSH) is a long-term study of the relationship between the variability in coarse particulate mass (PMcoarse, particulate matter between 2.5 and 10mum) and adverse health effects such as cardio-respiratory illnesses, pre-term births, and mortality. Hourly mass concentrations of PMcoarse and fine particulate matter (PM2.5) are measured using tapered element oscillating microbalances (TEOMs) with Filter Dynamics Measurement Systems (FDMS), at two rural and two urban sites. We present findings based on nine months of mass concentration data, including temporal trends, and non-parametric regressions (NPR) results, which were used to characterize the wind speed and wind direction relationships that might point to sources. As part of CRUSH, 1-year coarse and fine mode particulate matter filter sampling network, will allow us to characterize the chemical composition of the particulate matter collected and perform spatial comparisons. This work describes the construction and validation testing of four dichotomous filter samplers for this purpose. The use of dichotomous splitters with an approximate 2.5mum cut point, coupled with a 10mum cut diameter inlet head allows us to collect the separated size fractions that the collocated TEOMs collect continuously. Chemical analysis of the filters will include inorganic ions, organic compounds, EC, OC, and biological analyses. Side by side testing showed the cut diameters were in agreement with each other, and with a well characterized virtual impactor lent to the group by the University of Southern California. Error propagation was performed and uncertainty results were similar to the observed standard deviations.

Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

NASA Astrophysics Data System (ADS)

Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A. G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R. B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

2015-04-01

Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009-11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11-33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.

Data Assimilation to Improve CMAQ Model Estimates of Particulate Matter Pollution during Wintertime Persistent Cold Air Pool Events in Salt Lake City, Utah

NASA Astrophysics Data System (ADS)

Ivey, C. E.; Balachandran, S.; Russell, A. G.; Hu, Y.; Holmes, H.

2017-12-01

More than one million people live in Salt Lake Valley, Utah, where wintertime pollution reaches unhealthy levels due to the unique meteorology and orography of the region. Persistent cold air pool (PCAP) events occur when high pressure ridges create stagnant conditions over a valley, which hampers large-scale advection and reduces surface wind speeds. During PCAP periods the fraction of incoming solar radiation that reaches the valley floor is also reduced, leading to temperature inversions that allow pollution to build. Pollution levels continue to climb until a washout event removes the pollutants from the valley. Washout events include high winds or precipitation events with advection or wet deposition related removal processes, respectively. In this work, novel data assimilation and source apportionment techniques are applied for January and February 2007 to analyze CMAQ-modeled source composition and source impacts for the Salt Lake Valley during PCAP events. First, a hybrid source-oriented apportionment model is applied over continental U.S. to determine observation and model-based impacts from 20 sources, including agricultural activities, fossil fuel combustion, dust, and metals processing. Then, a secondary bias correction method is applied to better quantify the source impacts on secondary PM2.5, which constitutes the majority of the PM2.5 mass. Revised concentrations reflect what was previously reported in studies of PCAP pollution in the Salt Lake Valley, where the dominant aerosol was found to be ammonium nitrate. Further, gasoline and natural gas combustion were found to be the greatest contributing sources to aerosol concentrations during the PCAP events. The benefit of the data assimilation methods is the availability of spatially and temporally resolved model estimates of source impacts that better reflect observed concentrations.

Identification and elucidation of anthropogenic source contribution in PM10 pollutant: Insight gain from dispersion and receptor models.

PubMed

Roy, Debananda; Singh, Gurdeep; Yadav, Pankaj

2016-10-01

Source apportionment study of PM 10 (Particulate Matter) in a critically polluted area of Jharia coalfield, India has been carried out using Dispersion model, Principle Component Analysis (PCA) and Chemical Mass Balance (CMB) techniques. Dispersion model Atmospheric Dispersion Model (AERMOD) was introduced to simplify the complexity of sources in Jharia coalfield. PCA and CMB analysis indicates that monitoring stations near the mining area were mainly affected by the emission from open coal mining and its associated activities such as coal transportation, loading and unloading of coal. Mine fire emission also contributed a considerable amount of particulate matters in monitoring stations. Locations in the city area were mostly affected by vehicular, Liquid Petroleum Gas (LPG) & Diesel Generator (DG) set emissions, residential, and commercial activities. The experimental data sampling and their analysis could aid understanding how dispersion based model technique along with receptor model based concept can be strategically used for quantitative analysis of Natural and Anthropogenic sources of PM 10 . Copyright © 2016. Published by Elsevier B.V.

Seasonal trends, chemical speciation and source apportionment of fine PM in Tehran

NASA Astrophysics Data System (ADS)

Arhami, Mohammad; Hosseini, Vahid; Zare Shahne, Maryam; Bigdeli, Mostafa; Lai, Alexandra; Schauer, James J.

2017-03-01

Frequent air pollution episodes have been reported for Tehran, Iran, mainly because of critically high levels of fine particulate matter (PM2.5). The composition and sources of these particles are poorly known, so this study aims to identify the major components and heavy metals in PM2.5 along with their seasonal trends and associated sources. 24-hour PM2.5 samples were collected at a main residential station every 6 days for a full year from February 2014 to February 2015. The samples were analyzed for ions, organic carbon (including water-soluble and insoluble portions), elemental carbon (EC), and all detectable elements. The dominant mass components, which were determined by means of chemical mass closure, were organic matter (35%), dust (25%), non-sea salt sulfate (11%), EC (9%), ammonium (5%), and nitrate (2%). Organic matter and EC together comprised 44% of fine PM on average (increased to >70% in the colder season), which reflects the significance of anthropogenic urban sources (i.e. vehicles). The contributions of different components varied considerably throughout the year, particularly the dust component that varied from 7% in the cold season to 56% in the hot and dry season. Principal component analyses were applied, resulting in 5 major source factors that explained 85% of the variance in fine PM. Factor 1, representing soil dust, explained 53%; Factor 2 denotes heavy metals mainly found in industrial sources and accounted for 18%; and rest of factors, mainly representing combustion sources, explained 14% of the variation. The levels of major heavy metals were further evaluated, and their trends showed considerable increases during cold seasons. The results of this study provide useful insight to fine PM in Tehran, which could help in identifying their health effects and sources, and also adopting effective control strategies.

New directions: Beyond sulphur, vanadium and nickel - About source apportionment of ship emissions in emission control areas

NASA Astrophysics Data System (ADS)

Czech, Hendryk; Schnelle-Kreis, Jürgen; Streibel, Thorsten; Zimmermann, Ralf

2017-08-01

During the oil crises of the 70s and the associated increase of the oil price, the usage of marine fuels shifted from middle distillates of the crude oil refinery, such as marine diesel oil (MDO) or marine gas oil (MGO), towards cheaper heavy fuel oils (HFO), or also called residual fuel oil. The latter refers to the vacuum residue of the crude oil refinery blended by lighter refinery products, such as kerosene, to meet a certain maximum viscosity. Those HFOs are rich in sulphur and heavy metals which end up as significant constituents in emitted fine particulate matter (PM2.5) after the combustion. Especially for harbour cities or highly frequented ship traffic routes, HFO-derived PM2.5 has been identified as a globally important perpetrator of increased mortality by cardiopulmonary diseases and lung cancer (e.g. Corbett et al., 2007). However, the emitted hazardous species provide reliable markers to assess the contribution of this emission source to air pollution in source apportionment studies. Such studies are often performed utilising positive matrix factorisation, whose score matrix can be interpreted as temporal contribution of k identified emission sources and factors represent the k corresponding emission profiles. If one of the k factors contains moderate to high amounts of sulphate, vanadium and nickel with a high ratio of the two latter ones, the ship identification was unambiguous (e.g. Viana et al., 2009). Even more sensitive towards emission profiles are receptor models such as chemical mass balance, which require detailed prior knowledge about the assumed emission sources (Jeong et al., 2017).

Source apportionment and health risk assessment of PM10 in a naturally ventilated school in a tropical environment.

PubMed

Mohamad, Noorlin; Latif, Mohd Talib; Khan, Md Firoz

2016-02-01

This study aimed to investigate the chemical composition and potential sources of PM10 as well as assess the potential health hazards it posed to school children. PM10 samples were taken from classrooms at a school in Kuala Lumpur's city centre (S1) and one in the suburban city of Putrajaya (S2) over a period of eight hours using a low volume sampler (LVS). The composition of the major ions and trace metals in PM10 were then analysed using ion chromatography (IC) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. The results showed that the average PM10 concentration inside the classroom at the city centre school (82µg/m(3)) was higher than that from the suburban school (77µg/m(3)). Principal component analysis-absolute principal component scores (PCA-APCS) revealed that road dust was the major source of indoor PM10 at both school in the city centre (36%) and the suburban location (55%). The total hazard quotient (HQ) calculated, based on the formula suggested by the United States Environmental Protection Agency (USEPA), was found to be slightly higher than the acceptable level of 1, indicating that inhalation exposure to particle-bound non-carcinogenic metals of PM10, particularly Cr exposure by children and adults occupying the school environment, was far from negligible. Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical characteristics and source apportionment of indoor and outdoor fine particles observed in an urban environment in Korea

NASA Astrophysics Data System (ADS)

Heo, J.; Yi, S. M.

2016-12-01

Paired indoor-outdoor fine particulate matter (PM2.5) samples were collected at subway stations, underground shopping centers, and schools in Seoul metropolitan over a 4-year period between 2004 and 2007. Relationships between indoor and outdoor PM2.5 chemical species were determined and source contributions to indoor and outdoor PM2.5 mass were estimated using a positive matrix factorization (PMF) model. The PM2.5 samples were analyzed for major chemical components including organic carbon and elemental carbon, ions, and metals, and the results were used in the PMF model. The levels of the PM2.5 mass and its chemical components observed at the indoor sites were higher than those at the outdoor sites. Indoor levels of ions (i.e. sulfate, nitrate, ammonium), elemental carbon, and several metals (i.e. Fe, Zn, and Cu) were found to be significantly affected by outdoor sources. Very high indoor-to-outdoor mass ratio of these chemical components, in particular, were observed, representing the significant impacts of outdoor sources on indoor levels of them. Seven sources (secondary sulfate, secondary nitrate, mobile, biomass burning, roadway emissions, dust, and sea salt) were resolved by the PMF model at both of the indoor and outdoor sites. The secondary inorganic aerosol (i.e. secondary sulfate and nitrate) and the mobile sources were major contributors to the indoor and outdoor PM2.5, accounting for 47% and 27% of the outdoor PM2.5 and 40% and 25% of the indoor PM2.5, respectively. Furthermore, the contributions of the secondary inorganic aerosol and the mobile sources to the indoor PM2.5 were very comparable to its corresponding contributions to the outdoor PM2.5 levels. The spatial and temporal characteristics of each of sources resolved by the PMF model across the sites were examined using summary statistics, correlation analysis, and coefficient of variation and divergence analysis and the detailed results will be discussed in the presentation.

Seasonal variations and source apportionment of atmospheric PM2.5-bound polycyclic aromatic hydrocarbons in a mixed multi-function area of Hangzhou, China.

PubMed

Lu, Hao; Wang, Shengsheng; Li, Yun; Gong, Hui; Han, Jingyi; Wu, Zuliang; Yao, Shuiliang; Zhang, Xuming; Tang, Xiujuan; Jiang, Boqiong

2017-07-01

To reveal the seasonal variations and sources of PM 2.5 -bound polycyclic aromatic hydrocarbons (PAHs) during haze and non-haze episodes, daily PM 2.5 samples were collected from March 2015 to February 2016 in a mixed multi-function area in Hangzhou, China. Ambient concentrations of 16 priority-controlled PAHs were determined. The sums of PM 2.5 -bound PAH concentrations during the haze episodes were 4.52 ± 3.32 and 13.6 ± 6.29 ng m -3 in warm and cold seasons, respectively, which were 1.99 and 1.49 times those during the non-haze episodes. Four PAH sources were identified using the positive matrix factorization model and conditional probability function, which were vehicular emissions (45%), heavy oil combustion (23%), coal and natural gas combustion (22%), and biomass combustion (10%). The four source concentrations of PAHs consistently showed higher levels in the cold season, compared with those in the warm season. Vehicular emissions were the most considerable sources that result in the increase of PM 2.5 -bound PAH levels during the haze episodes, and heavy oil combustion played an important role in the aggravation of haze pollution. The analysis of air mass back trajectories indicated that air mass transport had an influence on the PM 2.5 -bound PAH pollution, especially on the increased contributions from coal combustion and vehicular emissions in the cold season.

pH of Aerosols in a Polluted Atmosphere: Source Contributions to Highly Acidic Aerosol.

PubMed

Shi, Guoliang; Xu, Jiao; Peng, Xing; Xiao, Zhimei; Chen, Kui; Tian, Yingze; Guan, Xinbei; Feng, Yinchang; Yu, Haofei; Nenes, Athanasios; Russell, Armistead G

2017-04-18

Acidity (pH) plays a key role in the physical and chemical behavior of PM 2.5 . However, understanding of how specific PM sources impact aerosol pH is rarely considered. Performing source apportionment of PM 2.5 allows a unique link of sources pH of aerosol from the polluted city. Hourly water-soluble (WS) ions of PM 2.5 were measured online from December 25th, 2014 to June 19th, 2015 in a northern city in China. Five sources were resolved including secondary nitrate (41%), secondary sulfate (26%), coal combustion (14%), mineral dust (11%), and vehicle exhaust (9%). The influence of source contributions to pH was estimated by ISORROPIA-II. The lowest aerosol pH levels were found at low WS-ion levels and then increased with increasing total ion levels, until high ion levels occur, at which point the aerosol becomes more acidic as both sulfate and nitrate increase. Ammonium levels increased nearly linearly with sulfate and nitrate until approximately 20 μg m -3 , supporting that the ammonium in the aerosol was more limited by thermodynamics than source limitations, and aerosol pH responded more to the contributions of sources such as dust than levels of sulfate. Commonly used pH indicator ratios were not indicative of the pH estimated using the thermodynamic model.

Chemical characteristics and source apportionment of PM2.5 between heavily polluted days and other days in Zhengzhou, China.

PubMed

Jiang, Nan; Li, Qiang; Su, Fangcheng; Wang, Qun; Yu, Xue; Kang, Panru; Zhang, Ruiqin; Tang, Xiaoyan

2018-04-01

PM 2.5 samples were collected in Zhengzhou during 3years of observation, and chemical characteristics and source contribution were analyzed. Approximately 96% of the daily PM 2.5 concentrations and annual average values exceeded the Chinese National Ambient Air Quality Daily and Annual Standards, indicating serious PM 2.5 pollution. The average concentration of water-soluble inorganic ions was 2.4 times higher in heavily polluted days (daily PM 2.5 concentrations>250μg/m 3 and visibility <3km) than that in other days, with sulfate, nitrate, and ammonium as major ions. According to the ratio of NO 3 - /SO 4 2- , stationary sources are still the dominant source of PM 2.5 and vehicle emission could not be ignored. The ratio of secondary organic carbon to organic carbon indicated that photochemical reactivity in heavily polluted days was more intense than in other days. Crustal elements were the most abundant elements, accounting for more than 60% of 23 elements. Chemical Mass Balance results indicated that the contributions of major sources (i.e., nitrate, sulfate, biomass, carbon and refractory material, coal combustion, soil dust, vehicle, and industry) of PM 2.5 were 13%, 16%, 12%, 2%, 14%, 8%, 7%, and 8% in heavily polluted days and 20%, 18%, 9%, 2%, 27%, 14%, 15%, and 9% in other days, respectively. Extensive combustion activities were the main sources of polycyclic aromatic hydrocarbons during the episode (Jan 1-9, 2015) and the total benzo[a]pyrene equivalency concentrations in heavily polluted days present significant health threat. Because of the effect of regional transport, the pollution level of PM 2.5 in the study area was aggravated. Copyright © 2017. Published by Elsevier B.V.

Behavior of the main sources that contribute to ambient PM2.5 in Santiago since 1998

NASA Astrophysics Data System (ADS)

Barraza, F.; Lambert, F.; Jorquera, H.; Villalobos, A. M.; Gallardo, L.

2016-12-01

Santiago's inhabitants have been exposed to high concentrations of fine particle matter (PM2.5) for decades. To contribute to a solution for this long-standing problem it is necessary to clearly identify and quantify the agents that contribute to ambient levels of PM2.5. We present an analysis of a long historical elemental concentrations database measured in air filter particles taken in central Santiago from April 1998 to August 2012 (1243 daily samples). We identify and quantify the main sources that contribute to PM2.5 levels using the source-receptor models PMF 5.0 and UNMIX 6.0. . The 6 main sources that contribute to outdoor PM2.5 levels were: vehicles (13.26±0.42 µg/m3), industrial sulfates (6.60±0.0.47 µg/m3), copper smelters (5.12±0.29 µg/m3), residential wood burning (4.38±0.36 µg/m3), marine aerosols (3.39±0.24 µg/m3), and urban dust (1.07±0.42 µg/m3). The unexplained fraction amounts to 1.76±0.90 µg/m3). The similar results obtained with both receptor models suggest a robust estimation of the main Santiago PM2.5 source apportionment. The analysis of the time series of these sources shows that their absolute contribution to PM2.5 levels has been decreasing during the last decade (except for urban dust which is increasing), and shows the effectiveness of government emission reduction policies. However, these improvements have not been sufficient to reduce PM2.5 concentrations to daily levels below the Chilean standard of 50 µg/m3, let alone the WHO standard of 25 µg/m3.

Part 2. Development of Enhanced Statistical Methods for Assessing Health Effects Associated with an Unknown Number of Major Sources of Multiple Air Pollutants.

PubMed

Park, Eun Sug; Symanski, Elaine; Han, Daikwon; Spiegelman, Clifford

2015-06-01

A major difficulty with assessing source-specific health effects is that source-specific exposures cannot be measured directly; rather, they need to be estimated by a source-apportionment method such as multivariate receptor modeling. The uncertainty in source apportionment (uncertainty in source-specific exposure estimates and model uncertainty due to the unknown number of sources and identifiability conditions) has been largely ignored in previous studies. Also, spatial dependence of multipollutant data collected from multiple monitoring sites has not yet been incorporated into multivariate receptor modeling. The objectives of this project are (1) to develop a multipollutant approach that incorporates both sources of uncertainty in source-apportionment into the assessment of source-specific health effects and (2) to develop enhanced multivariate receptor models that can account for spatial correlations in the multipollutant data collected from multiple sites. We employed a Bayesian hierarchical modeling framework consisting of multivariate receptor models, health-effects models, and a hierarchical model on latent source contributions. For the health model, we focused on the time-series design in this project. Each combination of number of sources and identifiability conditions (additional constraints on model parameters) defines a different model. We built a set of plausible models with extensive exploratory data analyses and with information from previous studies, and then computed posterior model probability to estimate model uncertainty. Parameter estimation and model uncertainty estimation were implemented simultaneously by Markov chain Monte Carlo (MCMC*) methods. We validated the methods using simulated data. We illustrated the methods using PM2.5 (particulate matter ≤ 2.5 μm in aerodynamic diameter) speciation data and mortality data from Phoenix, Arizona, and Houston, Texas. The Phoenix data included counts of cardiovascular deaths and daily PM2.5 speciation data from 1995-1997. The Houston data included respiratory mortality data and 24-hour PM2.5 speciation data sampled every six days from a region near the Houston Ship Channel in years 2002-2005. We also developed a Bayesian spatial multivariate receptor modeling approach that, while simultaneously dealing with the unknown number of sources and identifiability conditions, incorporated spatial correlations in the multipollutant data collected from multiple sites into the estimation of source profiles and contributions based on the discrete process convolution model for multivariate spatial processes. This new modeling approach was applied to 24-hour ambient air concentrations of 17 volatile organic compounds (VOCs) measured at nine monitoring sites in Harris County, Texas, during years 2000 to 2005. Simulation results indicated that our methods were accurate in identifying the true model and estimated parameters were close to the true values. The results from our methods agreed in general with previous studies on the source apportionment of the Phoenix data in terms of estimated source profiles and contributions. However, we had a greater number of statistically insignificant findings, which was likely a natural consequence of incorporating uncertainty in the estimated source contributions into the health-effects parameter estimation. For the Houston data, a model with five sources (that seemed to be Sulfate-Rich Secondary Aerosol, Motor Vehicles, Industrial Combustion, Soil/Crustal Matter, and Sea Salt) showed the highest posterior model probability among the candidate models considered when fitted simultaneously to the PM2.5 and mortality data. There was a statistically significant positive association between respiratory mortality and same-day PM2.5 concentrations attributed to one of the sources (probably industrial combustion). The Bayesian spatial multivariate receptor modeling approach applied to the VOC data led to a highest posterior model probability for a model with five sources (that seemed to be refinery, petrochemical production, gasoline evaporation, natural gas, and vehicular exhaust) among several candidate models, with the number of sources varying between three and seven and with different identifiability conditions. Our multipollutant approach assessing source-specific health effects is more advantageous than a single-pollutant approach in that it can estimate total health effects from multiple pollutants and can also identify emission sources that are responsible for adverse health effects. Our Bayesian approach can incorporate not only uncertainty in the estimated source contributions, but also model uncertainty that has not been addressed in previous studies on assessing source-specific health effects. The new Bayesian spatial multivariate receptor modeling approach enables predictions of source contributions at unmonitored sites, minimizing exposure misclassification and providing improved exposure estimates along with their uncertainty estimates, as well as accounting for uncertainty in the number of sources and identifiability conditions.

Fine particulate matter associated with monsoonal effect and the responses of biomass fire hotspots in the tropical environment

NASA Astrophysics Data System (ADS)

Khan, M. F.; Latif, M. T.; Saw, W. H.; Amil, N.; Nadzir, M. S. M.; Sahani, M.; Tahir, N. M.; Chung, J. X.

2015-08-01

The health implications of PM2.5 in tropical regions of Southeast Asia are significant as PM2.5 can pose serious health concerns. PM2.5 is strongly influenced by the monsoon. We quantitatively characterize the health risks posed to human populations by selected heavy metals in PM2.5. Monsoonal effects as well as factors influencing the sources of PM2.5 were also determined. Apportionment analysis of PM2.5 was undertaken using US EPA positive matrix factorization (PMF) 5.0 and a mass closure model. Overall, 48 % of the samples exceeded the World Health Organization (WHO) 24 h guideline. The mass closure model identified four sources of PM2.5: (a) mineral matter (MIN) (35 %), (b) secondary inorganic aerosol (SIA) (11 %), (c) sea salt (SS) (7 %), (d) trace elements (TE) (2 %) and (e) undefined (UD) (45 %). PMF 5.0 identified five potential sources and motor vehicle emissions and biomass burning were dominant followed by marine and sulfate aerosol, coal burning, nitrate aerosol, and mineral and road dust. The non-carcinogenic risk level for four selected metals (Pb, As, Cd and Ni) in PM2.5 and in the identified major sources by PMF > 5.0, with respect to inhalation follows the order of PM2.5 > coal burning > motor vehicle emissions/biomass burning > mineral/road dust. The lifetime cancer risk follows the order of As > Ni > Pb > Cd for mineral/road dust, coal burning and overall of PM2.5 concentration and As > Pb > Ni > Cd for motor vehicle/biomass burning. Overall, the associated cancer risk posed by the exposure of toxic metals in PM2.5 is three to four in 1 000 000 people in this location.

How Does the Amount and Composition of PM Deposited on Platanus acerifolia Leaves Change Across Different Cities in Europe?

PubMed

Baldacchini, Chiara; Castanheiro, Ana; Maghakyan, Nairuhi; Sgrigna, Gregorio; Verhelst, Jolien; Alonso, Rocío; Amorim, Jorge H; Bellan, Patrick; Bojović, Danijela Đunisijević; Breuste, Jürgen; Bühler, Oliver; Cântar, Ilie C; Cariñanos, Paloma; Carriero, Giulia; Churkina, Galina; Dinca, Lucian; Esposito, Raffaela; Gawroński, Stanisław W; Kern, Maren; Le Thiec, Didier; Moretti, Marco; Ningal, Tine; Rantzoudi, Eleni C; Sinjur, Iztok; Stojanova, Biljana; Aničić Urošević, Mira; Velikova, Violeta; Živojinović, Ivana; Sahakyan, Lilit; Calfapietra, Carlo; Samson, Roeland

2017-02-07

Particulate matter (PM) deposited on Platanus acerifolia tree leaves has been sampled in the urban areas of 28 European cities, over 20 countries, with the aim of testing leaf deposited particles as indicator of atmospheric PM concentration and composition. Leaves have been collected close to streets characterized by heavy traffic and within urban parks. Leaf surface density, dimensions, and elemental composition of leaf deposited particles have been compared with leaf magnetic content, and discussed in connection with air quality data. The PM quantity and size were mainly dependent on the regional background concentration of particles, while the percentage of iron-based particles emerged as a clear marker of traffic-related pollution in most of the sites. This indicates that Platanus acerifolia is highly suitable to be used in atmospheric PM monitoring studies and that morphological and elemental characteristics of leaf deposited particles, joined with the leaf magnetic content, may successfully allow urban PM source apportionment.

Apportionment of the sources of high fine particulate matter concentration events in a developing aerotropolis in Taoyuan, Taiwan.

PubMed

Chuang, Ming-Tung; Chen, Yu-Chieh; Lee, Chung-Te; Cheng, Chung-Hao; Tsai, Yu-Jen; Chang, Shih-Yu; Su, Zhen-Sen

2016-07-01

To investigate the characteristics and contributions of the sources of fine particulate matter with a size of up to 2.5 μm (PM2.5) during the period when pollution events could easily occur in Taoyuan aerotropolis, Taiwan, this study conducted sampling at three-day intervals from September 2014 to January 2015. Based on the mass concentration of PM2.5, the sampling days were classified into high PM2.5 concentration event days (PM2.5>35 μg m(-3)) and non-event days (PM2.5<35 μg m(-3)). In addition, the chemical species, including water-soluble inorganic ions, carbonaceous components, and metal elements, were analyzed. The sources of pollution and their contributions were estimated using the positive matrix factorization (PMF) model. Furthermore, the effect of the weather type on the measurement results was also explored based on wind field conditions. The mass fractions of Cl(-) and NO3(-) increased when a high PM2.5 concentration event occurred, and they were also higher under local emitted conditions than under long range transported conditions, indicating that secondary nitrate aerosols were the major increasing local species that caused high PM2.5 concentration events. Seven sources of pollution could be distinguished using the PMF model on the basis of the characteristics of the species. Industrial emissions, coal combustion/urban waste incineration, and local emissions from diesel/gasoline vehicles were the main sources that contributed to pollution on high PM2.5 concentration event days. In order to reduction of high PM2.5 concentration events, the control of diesel and gasoline vehicle emission is important and should be given priority. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparative source apportionment of PM10 in Switzerland for 2008/2009 and 1998/1999 by Positive Matrix Factorisation

NASA Astrophysics Data System (ADS)

Gianini, M. F. D.; Fischer, A.; Gehrig, R.; Ulrich, A.; Wichser, A.; Piot, C.; Besombes, J.-L.; Hueglin, C.

2012-07-01

PM10 speciation data from various sites in Switzerland for two time periods (January 1998-March 1999 and August 2008-July 2009) have been analysed for major sources by receptor modelling using Positive Matrix Factorisation (PMF). For the 2008/2009 period, it was found that secondary aerosols (sulphate- and nitrate-rich secondary aerosols, SSA and NSA) are the most abundant components of PM10 at sites north of the Alps. Road traffic and wood combustion were found to be the largest sources of PM10 at these sites. Except at the urban roadside site where road traffic is dominating (40% of PM10 -- including road salt), the annual average contribution of these two sources is of similar importance (17% and 14% of PM10, respectively). At a rural site south of the Alps wood combustion and road traffic contributions to PM10 were higher (31% and 24%, respectively), and the fraction of secondary aerosols lower (29%) than at similar site types north of the Alps. Comparison of PMF analyses for the two time periods (1998/1999 and 2008/2009) revealed decreasing average contributions of road traffic and SSA to PM10 at all sites. This indicates that the measures that were implemented in Switzerland and in neighbouring countries to reduce emissions of sulphur dioxide and PM10 from road traffic were successful. On the other hand, contributions of wood combustion did not change during this ten year period, and the contribution of nitrate-rich secondary aerosols has even increased. It is shown that PMF can be a helpful tool for the assessment of long-term changes of source contributions to ambient particulate matter.

PM2.5 Characterization for Time Series Studies: Organic Molecular Marker Speciation Methods and Observations from Daily Measurements in Denver

PubMed Central

Dutton, Steven J.; Williams, Daniel E.; Garcia, Jessica K.; Vedal, Sverre; Hannigan, Michael P.

2009-01-01

Particulate matter less than 2.5 microns in diameter (PM2.5) has been shown to have a wide range of adverse health effects and consequently is regulated in accordance with the US-EPA’s National Ambient Air Quality Standards. PM2.5 originates from multiple primary sources and is also formed through secondary processes in the atmosphere. It is plausible that some sources form PM2.5 that is more toxic than PM2.5 from other sources. Identifying the responsible sources could provide insight into the biological mechanisms causing the observed health effects and provide a more efficient approach to regulation. This is the goal of the Denver Aerosol Sources and Health (DASH) study, a multi-year PM2.5 source apportionment and health study. The first step in apportioning the PM2.5 to different sources is to determine the chemical make-up of the PM2.5. This paper presents the methodology used during the DASH study for organic speciation of PM2.5. Specifically, methods are covered for solvent extraction of non-polar and semi-polar organic molecular markers using gas chromatography-mass spectrometry (GC-MS). Vast reductions in detection limits were obtained through the use of a programmable temperature vaporization (PTV) inlet along with other method improvements. Results are presented for the first 1.5 years of the DASH study revealing seasonal and source-related patterns in the molecular markers and their long-term correlation structure. Preliminary analysis suggests that point sources are not a significant contributor to the organic molecular markers measured at our receptor site. Several motor vehicle emission markers help identify a gasoline/diesel split in the ambient data. Findings show both similarities and differences when compared with other cities where similar measurements and assessments have been made. PMID:20161318

The size distribution and origin of elements bound to ambient particles: a case study of a Polish urban area.

PubMed

Rogula-Kozłowska, Wioletta; Majewski, Grzegorz; Czechowski, Piotr Oskar

2015-05-01

Ambient particulate matter (PM) was sampled in Zabrze (southern Poland) in the heating period of 2009. It was investigated for distribution of its mass and of the masses of its 18 component elements (S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Ge, As, Br, Sr, Cd, Sb, Ba, and Pb) among 13 PM size fractions. In the paper, the distribution modality of and the correlations between the ambient concentrations of these elements are discussed and interpreted in terms of the source apportionment of PM emissions. By weight, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Ge, As, Br, Sr, Cd, Sb, Ba, and Pb were 10% of coarse and 9% of ultrafine particles. The collective mass of these elements was no more than 3.5 % of the mass of the particles with the aerodynamic diameter D p between 0.4 and 1.0 μm (PM₀.₄₋₁), whose ambient mass concentration was the highest. The PM mass size distribution for the sampling period is bimodal; it has the accumulation and coarse modes. The coarse particles were probably of the mineral/soil origin (characteristic elements: Ca, Fe, Sr, and Ba), being re-suspended polluted soil or road dust (characteristic elements: Ca, Fe, Sr, Ba, S, K, Cr, Cu, Zn, Br, Sb, Pb). The maxima of the density functions (modes) of the concentration distributions with respect to particle size of PM-bound S, Cl, K, Cu, Zn, Ge, Br, Cd, Sb, and Pb within the D p interval from 0.108 to 1.6 μm (accumulation PM particles) indicate the emissions from furnaces and road traffic. The distributions of PM-bound As, Mn, Ba, and Sr concentrations have their modes within D p ≤ 0.108 μm (nucleation PM particles), indicating the emissions from high-temperature processes (industrial sources or car engines). In this work, principal component analysis (PCA) is applied separately to each of the 13 fraction-related sets of the concentrations of the 18 PM-bound elements, and further, the fractions are grouped by their origin using cluster analysis (CA) applied to the 13 fraction-related first principal components (PC1). Four distinct groups of the PM fractions are identified: (PM₁.₆₋₂.₅, PM₂.₅₋₄.₄,), (PM₀.₀₃₋₀.₀₆, PM₀.₁₀₈₋₀.₁₇), (PM₀.₀₆₋₀.₁₀₈, PM₀.₁₇₋₀.₂₆, PM₀.₂₆₋₀.₄, PM₀.₄₋₀.₆₅, PM₀.₆₅₋₁, PM₁₋₁.₆), and (PM₄.₄₋₆.₈, PM₆.₈₋₁₀, PM>₁₀). The PM sources attributed to these groups by using PCA followed by CA are roughly the same as the sources from the apportionment done by analyzing the modality of the mass size distributions.

Oxidative potential of ambient PM2.5 in the coastal cities of the Bohai Sea, northern China: Seasonal variation and source apportionment.

PubMed

Liu, WeiJian; Xu, YunSong; Liu, WenXin; Liu, QingYang; Yu, ShuangYu; Liu, Yang; Wang, Xin; Tao, Shu

2018-05-01

Emissions of air pollutants from primary and secondary sources in China are considerably higher than those in developed countries, and exposure to air pollution is main risk of public health. Identifying specific particulate matter (PM) compositions and sources are essential for policy makers to propose effective control measures for pollutant emissions. Ambient PM 2.5 samples covered a whole year were collected from three coastal cities of the Bohai Sea. Oxidative potential (OP) was selected as the indicator to characterize associated PM compositions and sources most responsible for adverse impacts on human health. Positive matrix factorization (PMF) and multiple linear regression (MLR) were employed to estimate correlations of PM 2.5 sources with OP. The volume- and mass-based dithiothreitol (DTT v and DTT m ) activities of PM 2.5 were significantly higher in local winter or autumn (p < 0.01). Spatial and seasonal variations in DTT v and DTT m were much larger than mass concentrations of PM 2.5 , indicated specific chemical components are responsible for PM 2.5 derived OP. Strong correlations (r > 0.700, p < 0.01) were found between DTT activity and water-soluble organic carbon (WSOC) and some transition metals. Using PMF, source fractions of PM 2.5 were resolved as secondary source, traffic source, biomass burning, sea spray and urban dust, industry, coal combustion, and mineral dust. Further quantified by MLR, coal combustion, biomass burning, secondary sources, industry, and traffic source were dominant contributors to the water-soluble DTT v activity. Our results also suggested large differences in seasonal contributions of different sources to DTT v variability. A higher contribution of DTT v was derived from coal combustion during the local heating period. Secondary sources exhibited a greater fraction of DTT v in summer, when there was stronger solar radiation. Traffic sources exhibited a prevailing contribution in summer, and industry contributed larger proportions in spring and winter. Future abatement priority of air pollution should reduce the sources contributing to OP of PM 2.5 . Copyright © 2018 Elsevier Ltd. All rights reserved.

Source apportionments of ambient fine particulate matter in Israeli, Jordanian, and Palestinian cities.

PubMed

Heo, Jongbae; Wu, Bo; Abdeen, Ziad; Qasrawi, Radwan; Sarnat, Jeremy A; Sharf, Geula; Shpund, Kobby; Schauer, James J

2017-06-01

This manuscript evaluates spatial and temporal variations of source contributions to ambient fine particulate matter (PM 2.5 ) in Israeli, Jordanian, and Palestinian cities. Twenty-four hour integrated PM 2.5 samples were collected every six days over a 1-year period (January to December 2007) in four cities in Israel (West Jerusalem, Eilat, Tel Aviv, and Haifa), four cities in Jordan (Amman, Aqaba, Rahma, and Zarka), and three cities in Palestine (Nablus, East Jerusalem, and Hebron). The PM 2.5 samples were analyzed for major chemical components, including organic carbon and elemental carbon, ions, and metals, and the results were used in a positive matrix factorization (PMF) model to estimate source contributions to PM 2.5 mass. Nine sources, including secondary sulfate, secondary nitrate, mobile, industrial lead sources, dust, construction dust, biomass burning, fuel oil combustion and sea salt, were identified across the sampling sites. Secondary sulfate was the dominant source, contributing 35% of the total PM 2.5 mass, and it showed relatively homogeneous temporal trends of daily source contribution in the study area. Mobile sources were found to be the second greatest contributor to PM 2.5 mass in the large metropolitan cities, such as Tel Aviv, Hebron, and West and East Jerusalem. Other sources (i.e. industrial lead sources, construction dust, and fuel oil combustion) were closely related to local emissions within individual cities. This study demonstrates how international cooperation can facilitate air pollution studies that address regional air pollution issues and the incremental differences across cities in a common airshed. It also provides a model to study air pollution in regions with limited air quality monitoring capacity that have persistent and emerging air quality problems, such as Africa, South Asia and Central America. Copyright © 2017 Elsevier Ltd. All rights reserved.

Source profiles of particulate matter emissions from a pilot-scale boiler burning North American coal blends.

PubMed

Lee, S W

2001-11-01

Recent awareness of suspected adverse health effects from ambient particulate matter (PM) emission has prompted publication of new standards for fine PM with aerodynamic diameter less than 2.5 microm (PM2.5). However, scientific data on fine PM emissions from various point sources and their characteristics are very limited. Source apportionment methods are applied to identify contributions of individual regional sources to tropospheric particulate concentrations. The existing industrial database developed using traditional source measurement techniques provides total emission rates only, with no details on chemical nature or size characteristics of particulates. This database is inadequate, in current form, to address source-receptor relationships. A source dilution system was developed for sampling and characterization of total PM, PM2.5, and PM10 (i.e., PM with aerodynamic diameter less than 10 pm) from residual oil and coal combustion. This new system has automatic control capabilities for key parameters, such as relative humidity (RH), temperature, and sample dilution. During optimization of the prototype equipment, three North American coal blends were burned using a 0.7-megawatt thermal (MWt) pulverized coal-fired, pilot-scale boiler. Characteristic emission profiles, including PM2.5 and total PM soluble acids, and elemental and carbon concentrations for three coal blends are presented. Preliminary results indicate that volatile trace elements such as Pb, Zn, Ti, and Se are preferentially enriched in PM2.5. PM2.5 is also more concentrated in soluble sulfates relative to total PM. Coal fly ash collected at the outlet of the electrostatic precipitator (ESP) contains about 85-90% PM10 and 30-50% PM2.5. Particles contain the highest elemental concentrations of Si and Al while Ca, Fe, Na, Ba, and K also exist as major elements. Approximately 4-12% of the materials exists as soluble sulfates in fly ash generated by coal blends containing 0.2-0.8% sulfur by mass. Source profile data for an eastern U.S. coal show good agreement with those reported from a similar study done in the United States. Based on the inadequacies identified in the initial sampling equipment, a new, plume-simulating fine PM measurement system with modular components for field use is being developed for determining coal combustion PM source profiles from utility boiler stacks.

Oxidative potential and inflammatory impacts of source apportioned ambient air pollution in Beijing.

PubMed

Liu, Qingyang; Baumgartner, Jill; Zhang, Yuanxun; Liu, Yanju; Sun, Yongjun; Zhang, Meigen

2014-11-04

Air pollution exposure is associated with a range of adverse health impacts. Knowledge of the chemical components and sources of air pollution most responsible for these health effects could lead to an improved understanding of the mechanisms of such effects and more targeted risk reduction strategies. We measured daily ambient fine particulate matter (<2.5 μm in aerodynamic diameter; PM2.5) for 2 months in peri-urban and central Beijing, and assessed the contribution of its chemical components to the oxidative potential of ambient air pollution using the dithiothreitol (DTT) assay. The composition data were applied to a multivariate source apportionment model to determine the PM contributions of six sources or factors: a zinc factor, an aluminum factor, a lead point factor, a secondary source (e.g., SO4(2-), NO3(2-)), an iron source, and a soil dust source. Finally, we assessed the relationship between reactive oxygen species (ROS) activity-related PM sources and inflammatory responses in human bronchial epithelial cells. In peri-urban Beijing, the soil dust source accounted for the largest fraction (47%) of measured ROS variability. In central Beijing, a secondary source explained the greatest fraction (29%) of measured ROS variability. The ROS activities of PM collected in central Beijing were exponentially associated with in vivo inflammatory responses in epithelial cells (R2=0.65-0.89). We also observed a high correlation between three ROS-related PM sources (a lead point factor, a zinc factor, and a secondary source) and expression of an inflammatory marker (r=0.45-0.80). Our results suggest large differences in the contribution of different PM sources to ROS variability at the central versus peri-urban study sites in Beijing and that secondary sources may play an important role in PM2.5-related oxidative potential and inflammatory health impacts.

Source Apportionment of PM2.5 Mass and Optical Attenuation Over an Ecologically Sensitive Zone in Central India by Positive Matrix Factorization

NASA Astrophysics Data System (ADS)

Nirmalkar, J.; Raman, R. S.

2016-12-01

Ambient PM2.5 samples (N=366) were collected over an ecologically sensitive zone (Van Vihar National Park) in Bhopal, Central India for two years (01 January, 2012 to 31 December, 2013). Samples were collected using three co-located Mini-Vol® samplers on Teflon, Nylon, and Quartz filter substrates. The aerosol was then chemically characterized for water-soluble inorganic ions, elements, and carbon fractions (elemental carbon and organic carbon) using ion chromatography, ED-XRF, and thermal-optical EC/OC analyzer, respectively. The optical attenuation (at 370 nm and 800 nm) of PM2.5 aerosols was also determined by optical transmissometry (OT-21). The application of Positive matrix factorization (PMF) to a combination of PM2.5 mass, its ions, elements, carbon fractions, and optical attenuation and its outcomes will be discussed.

Elemental characterization and source apportionment of PM10 and PM2.5 in the western coastal area of central Taiwan.

PubMed

Hsu, Chin-Yu; Chiang, Hung-Che; Lin, Sheng-Lun; Chen, Mu-Jean; Lin, Tzu-Yu; Chen, Yu-Cheng

2016-01-15

This study investigated seasonal variations in PM10 and PM2.5 mass and associated trace metal concentrations in a residential area in proximity to the crude oil refinery plants and industrial parks of central Taiwan. Particle measurements were conducted during winter, spring and summer in 2013 and 2014. Twenty-six trace metals in PM10 and PM2.5 were analyzed using ICP-MS. Multiple approaches of the backward trajectory model, enrichment factor (EF), Lanthanum enrichment and positive matrix fraction (PMF) were used to identify potential sources of particulate metals. Mean concentrations of PM10 in winter, spring and summer were 76.4 ± 22.6, 33.2 ± 9.9 and 37.4 ± 17.0 μg m(-3), respectively, while mean levels of PM2.5 in winter, spring and summer were 47.8 ± 20.0, 23.9 ± 11.2 and 16.3 ± 8.2 μg m(-3), respectively. The concentrations of carcinogenic metals (Ni, As and adjusted Cr(VI)) in PM10 and PM2.5 exceeded the guideline limits published by WHO. The result of EF analysis confirmed that Mo, Sb, Cd, Zn, Mg, Cr, As, Pb, Cu, Ni and V were attributable to anthropogenic emission. PMF analysis demonstrated that trace metals in PM10 and PM2.5 were from the similar sources, such as coal combustion, oil combustion and traffic-related emission, except for soil dust and crustal element emissions only observed in PM10 and secondary aluminum smelter only observed in PM2.5. Considering health-related particulate metals, the traffic-related emission and coal combustion for PM10 and PM2.5, respectively, are important to control for reducing potential carcinogenic risk. The results could aid efforts to clarify the impact of source-specific origins on human health. Copyright © 2015 Elsevier B.V. All rights reserved.

Source apportionment of major and trace elements in aerosols during smog episodes in large cities in China

NASA Astrophysics Data System (ADS)

Furger, Markus; Rai, Pragati; Visser, Suzanne; Elser, Miriam; Canonaco, Francesco; Slowik, Jay G.; Huang, Ru-Jin; Prévôt, André S. H.; Baltensperger, Urs

2017-04-01

Air pollution in Chinese cities is one of the environmental problems China has to address to mitigate the impacts on human health, air quality and climate. Average concentrations of particulate matter exceed 100 μg m-3 in many places in China, and the government is developing and implementing strategies to reduce the load of pollutants by various measures. A characterization of airborne particulate matter (PM), especially its composition and sources, will help in optimizing reduction and mitigation strategies for air pollution. We collected PM10 aerosols with a rotating drum impactor (RDI) in Xi'an in December 2013 and in Beijing in January 2014 with 30-min time resolution and for three size ranges (cut-off sizes 10, 2.5 and 1 μm). Each campaign encompassed one or more high pollution episodes in the respective city. Elements from Na to Pb were analyzed with synchrotron radiation induced X-ray fluorescence spectrometry (SR-XRF), and the resulting time series were used for source apportionment performed with the Multilinear-Engine 2 (ME-2) implementation of the Positive Matrix Factorization algorithm. The preliminary computations yielded 5 factors for Beijing, namely road dust, sea salt, traffic-related, industrial, coal combustion. For Xi'an an additional desert dust factor was found. Further refinement could be expected from including the smaller size fractions, e.g. a sulfur-rich factor for secondary sulfate or a reacted chlorine factor in the fine mode fraction.

Organic aerosol source apportionment by offline-AMS over a full year in Marseille

NASA Astrophysics Data System (ADS)

Bozzetti, Carlo; El Haddad, Imad; Salameh, Dalia; Daellenbach, Kaspar Rudolf; Fermo, Paola; Gonzalez, Raquel; Cruz Minguillón, María; Iinuma, Yoshiteru; Poulain, Laurent; Elser, Miriam; Müller, Emanuel; Gates Slowik, Jay; Jaffrezo, Jean-Luc; Baltensperger, Urs; Marchand, Nicolas; Prévôt, André Stephan Henry

2017-07-01

We investigated the seasonal trends of OA sources affecting the air quality of Marseille (France), which is the largest harbor of the Mediterranean Sea. This was achieved by measurements of nebulized filter extracts using an aerosol mass spectrometer (offline-AMS). In total 216 PM2. 5 (particulate matter with an aerodynamic diameter < 2.5 µm) filter samples were collected over 1 year from August 2011 to July 2012. These filters were used to create 54 composite samples which were analyzed by offline-AMS. The same samples were also analyzed for major water-soluble ions, metals, elemental and organic carbon (EC / OC), and organic markers, including n-alkanes, hopanes, polycyclic aromatic hydrocarbons (PAHs), lignin and cellulose pyrolysis products, and nitrocatechols. The application of positive matrix factorization (PMF) to the water-soluble AMS spectra enabled the extraction of five factors, related to hydrocarbon-like OA (HOA), cooking OA (COA), biomass burning OA (BBOA), oxygenated OA (OOA), and an industry-related OA (INDOA). Seasonal trends and relative contributions of OA sources were compared with the source apportionment of OA spectra collected from the AMS field deployment at the same station but in different years and for shorter monitoring periods (February 2011 and July 2008). Online- and offline-AMS source apportionment revealed comparable seasonal contribution of the different OA sources. Results revealed that BBOA was the dominant source during winter, representing on average 48 % of the OA, while during summer the main OA component was OOA (63 % of OA mass on average). HOA related to traffic emissions contributed on a yearly average 17 % to the OA mass, while COA was a minor source contributing 4 %. The contribution of INDOA was enhanced during winter (17 % during winter and 11 % during summer), consistent with an increased contribution from light alkanes, light PAHs (fluoranthene, pyrene, phenanthrene), and selenium, which is commonly considered as a unique coal combustion and coke production marker. Online- and offline-AMS source apportionments revealed evolving levoglucosan : BBOA ratios, which were higher during late autumn and March. A similar seasonality was observed in the ratios of cellulose combustion markers to lignin combustion markers, highlighting the contribution from cellulose-rich biomass combustion, possibly related to agricultural activities.

Characterization of ambient fine particles in the northwestern area and Anchorage, Alaska.

PubMed

Kim, Eugene; Hopke, Philip K

2008-10-01

Ambient PM2.5 (particulate matter less than 2.5 microm in aerodynamic diameter) in the northwestern United States and Alaska is dominated by carbonaceous compounds associated with wood burning and transportation sources. PM2.5 source characterization studies analyzing recent PM2.5 speciation data have not been previously reported for these areas. In this study, ambient PM2.5 speciation samples collected at two monitoring sites located in the northwestern area, Olympic Peninsula, WA, and Portland, OR, and one monitoring site located in Anchorage, AK, were characterized through source apportionments. Gasoline vehicle, secondary sulfate, and wood smoke were the largest sources of PM2.5 collected at the Anchorage, Olympic, and Portland monitoring sites, respectively. Secondary sulfates showed an April peak at Anchorage and a November peak at Portland that are likely related to the increased photochemical reaction and long-range transport in Anchorage and meteorological stagnation in Portland. Secondary nitrate at the Olympic site showed a weak summer high peak that could be caused by seasonal tourism in the national park. Backward trajectories suggested that the elevated aged sea salt concentrations at the Portland monitoring site could be regional transport of sea salt that passed through other contaminated air sheds along the coast. Oil combustion emissions that might originate from ships and ferries were observed at the Olympic monitoring site.

Characteristics and source apportionment of fine haze aerosol in Beijing during the winter of 2013

NASA Astrophysics Data System (ADS)

Shang, Xiaona; Zhang, Kai; Meng, Fan; Wang, Shihao; Lee, Meehye; Suh, Inseon; Kim, Daigon; Jeon, Kwonho; Park, Hyunju; Wang, Xuezhong; Zhao, Yuxi

2018-02-01

For PM2.5 filter samples collected daily at the Chinese Research Academy of Environmental Sciences (Beijing, China) from December of 2013 to February of 2014 (the winter period), chemical characteristics and sources were investigated with an emphasis on haze events in different alert levels. During the 3 months, the average PM2.5 concentration was 89 µg m-3, exceeding the Chinese national standard of 75 µg m-3 in 24  h. The maximum PM2.5 concentration was 307 µg m-3, which characterizes developed-type pollution (PM2.5 / PM10>0.5) in the World Health Organization criteria. PM2.5 was dominated by SO42-, NO3-, and pseudo-carbonaceous compounds with obvious differences in concentrations and proportions between non-haze and haze episodes. The non-negative matrix factorization (NMF) analysis provided reasonable PM2.5 source profiles, by which five sources were identified: soil dust, traffic emission, biomass combustion, industrial emission, and coal combustion accounting for 13, 22, 12, 28, and 25  % of the total, respectively. The dust impact increased with northwesterlies during non-haze periods and decreased under stagnant conditions during haze periods. A blue alert of heavy air pollution was characterized by the greatest contribution from industrial emissions (61  %). During the Chinese Lantern Festival, an orange alert was issued and biomass combustion was found to be the major source owing to firework explosions. Red-alert haze was almost equally contributed by local traffic and transported coal combustion emissions from the vicinity of Beijing (approximately 40  % each) that was distinguished by the highest levels of NO3- and SO42-, respectively. This study also reveals that the severity and source of haze are largely dependent on meteorological conditions.

Within-city contrasts in PM composition and sources and their relationship with nitrogen oxides.

PubMed

Minguillón, M C; Rivas, I; Aguilera, I; Alastuey, A; Moreno, T; Amato, F; Sunyer, J; Querol, X

2012-10-26

The present work is part of the INMA (INfancia y Medio Ambiente -'Environment and Childhood') project, which aims at assessing the adverse effects of exposure to air pollution during pregnancy and early in life. The present study was performed in the city of Sabadell (Northeast Spain) at three sampling sites covering different traffic characteristics, during two times of the year. It assesses time and spatial variations of PM(2.5) concentrations, chemical components and source contributions, as well as gaseous pollutants. Furthermore, a cross-correlation analysis of PM components and source contributions with gaseous pollutants used as a proxy for exposure assessment is carried out. Our data show the influence of traffic emissions in the Sabadell area. The main PM sources identified by Positive Matrix Factorisation (PMF) were similar between the two seasons: mineral source (traffic-induced resuspension, demolition/construction and natural background), secondary sulphate (higher in summer), secondary nitrate (only during winter), industrial, and road traffic, which was the main contributor to PM(2.5) at two of the sites. The correlation of concentrations of nitrogen oxides was especially strong with those of elemental carbon (EC). The relatively weaker correlations with organic carbon (OC) in summer are attributed to the variable formation of secondary OC. Strong correlations between concentration of nitrogen oxides and PM(2.5) road traffic contributions obtained from source apportionment analysis were seen at all sites. Therefore, under the studied urban environment, nitrogen oxides can be used as a proxy for the exposure to road traffic contribution to PM(2.5); the use of NO(x) concentrations being preferred, with NO and NO(2) as second and third options, respectively.

Comprehensive assessment of PM2.5 physicochemical properties during the Southeast Asia dry season (southwest monsoon)

NASA Astrophysics Data System (ADS)

Khan, Md Firoz; Sulong, Nor Azura; Latif, Mohd Talib; Nadzir, Mohd Shahrul Mohd; Amil, Norhaniza; Hussain, Dini Fajrina Mohd; Lee, Vernon; Hosaini, Puteri Nurafidah; Shaharom, Suhana; Yusoff, Nur Amira Yasmin Mohd; Hoque, Hossain Mohammed Syedul; Chung, Jing Xiang; Sahani, Mazrura; Mohd Tahir, Norhayati; Juneng, Liew; Maulud, Khairul Nizam Abdul; Abdullah, Sharifah Mastura Syed; Fujii, Yusuke; Tohno, Susumu; Mizohata, Akira

2016-12-01

A comprehensive assessment of fine particulate matter (PM2.5) compositions during the Southeast Asia dry season is presented. Samples of PM2.5 were collected between 24 June and 14 September 2014 using a high-volume sampler. Water-soluble ions, trace species, rare earth elements, and a range of elemental carbon (EC) and organic carbon were analyzed. The characterization and source apportionment of PM2.5 were investigated. The results showed that the 24 h PM2.5 concentration ranged from 6.64 to 68.2 µg m-3. Meteorological driving factors strongly governed the diurnal concentration of aerosol, while the traffic in the morning and evening rush hours coincided with higher levels of CO and NO2. The correlation analysis for non sea-salt K+-EC showed that EC is potentially associated with biomass burning events, while the formation of secondary organic carbon had a moderate association with motor vehicle emissions. Positive matrix factorization (PMF) version 5.0 identified the sources of PM2.5: (i) biomass burning coupled with sea salt [I] (7%), (ii) aged sea salt and mixed industrial emissions (5%), (iii) road dust and fuel oil combustion (7%), (iv) coal-fired combustion (25%), (v) mineral dust (8%), (vi) secondary inorganic aerosol (SIA) coupled with F- (15%), and (vii) motor vehicle emissions coupled with sea salt [II] (24%). Motor vehicle emissions, SIA, and coal-fired power plant are the predominant sources contributing to PM2.5. The response of the potential source contribution function and Hybrid Single-Particle Lagrangian Integrated Trajectory backward trajectory model suggest that the outline of source regions were consistent to the sources by PMF 5.0.

Preliminary Results of the first European Source Apportionment intercomparison for Receptor and Chemical Transport Models

NASA Astrophysics Data System (ADS)

Belis, Claudio A.; Pernigotti, Denise; Pirovano, Guido

2017-04-01

Source Apportionment (SA) is the identification of ambient air pollution sources and the quantification of their contribution to pollution levels. This task can be accomplished using different approaches: chemical transport models and receptor models. Receptor models are derived from measurements and therefore are considered as a reference for primary sources urban background levels. Chemical transport model have better estimation of the secondary pollutants (inorganic) and are capable to provide gridded results with high time resolution. Assessing the performance of SA model results is essential to guarantee reliable information on source contributions to be used for the reporting to the Commission and in the development of pollution abatement strategies. This is the first intercomparison ever designed to test both receptor oriented models (or receptor models) and chemical transport models (or source oriented models) using a comprehensive method based on model quality indicators and pre-established criteria. The target pollutant of this exercise, organised in the frame of FAIRMODE WG 3, is PM10. Both receptor models and chemical transport models present good performances when evaluated against their respective references. Both types of models demonstrate quite satisfactory capabilities to estimate the yearly source contributions while the estimation of the source contributions at the daily level (time series) is more critical. Chemical transport models showed a tendency to underestimate the contribution of some single sources when compared to receptor models. For receptor models the most critical source category is industry. This is probably due to the variety of single sources with different characteristics that belong to this category. Dust is the most problematic source for Chemical Transport Models, likely due to the poor information about this kind of source in the emission inventories, particularly concerning road dust re-suspension, and consequently the little detail about the chemical components of this source used in the models. The sensitivity tests show that chemical transport models show better performances when displaying a detailed set of sources (14) than when using a simplified one (only 8). It was also observed that an enhanced vertical profiling can improve the estimation of specific sources, such as industry, under complex meteorological conditions and that an insufficient spatial resolution in urban areas can impact on the capabilities of models to estimate the contribution of diffuse primary sources (e.g. traffic). Both families of models identify traffic and biomass burning as the first and second most contributing categories, respectively, to elemental carbon. The results of this study demonstrate that the source apportionment assessment methodology developed by the JRC is applicable to any kind of SA model. The same methodology is implemented in the on-line DeltaSA tool to support source apportionment model evaluation (http://source-apportionment.jrc.ec.europa.eu/).

Source apportionment of PM10 by positive matrix factorization in urban area of Mumbai, India.

PubMed

Gupta, Indrani; Salunkhe, Abhaysinh; Kumar, Rakesh

2012-01-01

Particulate Matter (PM(10)) has been one of the main air pollutants exceeding the ambient standards in most of the major cities in India. During last few years, receptor models such as Chemical Mass Balance, Positive Matrix Factorization (PMF), PCA-APCS and UNMIX have been used to provide solutions to the source identification and contributions which are accepted for developing effective and efficient air quality management plans. Each site poses different complexities while resolving PM(10) contributions. This paper reports the variability of four sites within Mumbai city using PMF. Industrial area of Mahul showed sources such as residual oil combustion and paved road dust (27%), traffic (20%), coal fired boiler (17%), nitrate (15%). Residential area of Khar showed sources such as residual oil combustion and construction (25%), motor vehicles (23%), marine aerosol and nitrate (19%), paved road dust (18%) compared to construction and natural dust (27%), motor vehicles and smelting work (25%), nitrate (16%) and biomass burning and paved road dust (15%) in Dharavi, a low income slum residential area. The major contributors of PM(10) at Colaba were marine aerosol, wood burning and ammonium sulphate (24%), motor vehicles and smelting work (22%), Natural soil (19%), nitrate and oil burning (18%).

Source apportionment and location by selective wind sampling and Positive Matrix Factorization.

PubMed

Venturini, Elisa; Vassura, Ivano; Raffo, Simona; Ferroni, Laura; Bernardi, Elena; Passarini, Fabrizio

2014-10-01

In order to determine the pollution sources in a suburban area and identify the main direction of their origin, PM2.5 was collected with samplers coupled with a wind select sensor and then subjected to Positive Matrix Factorization (PMF) analysis. In each sample, soluble ions, organic carbon, elemental carbon, levoglucosan, metals, and Polycyclic Aromatic Hydrocarbons (PAHs) were determined. PMF results identified six main sources affecting the area: natural gas home appliances, motor vehicles, regional transport, biomass combustion, manufacturing activities, and secondary aerosol. The connection of factor temporal trends with other parameters (i.e., temperature, PM2.5 concentration, and photochemical processes) confirms factor attributions. PMF analysis indicated that the main source of PM2.5 in the area is secondary aerosol. This should be mainly due to regional contributions, owing to both the secondary nature of the source itself and the higher concentration registered in inland air masses. The motor vehicle emission source contribution is also important. This source likely has a prevalent local origin. The most toxic determined components, i.e., PAHs, Cd, Pb, and Ni, are mainly due to vehicular traffic. Even if this is not the main source in the study area, it is the one of greatest concern. The application of PMF analysis to PM2.5 collected with this new sampling technique made it possible to obtain more detailed results on the sources affecting the area compared to a classical PMF analysis.

PMF and PSCF based source apportionment of PM2.5 at a regional background site in North China

NASA Astrophysics Data System (ADS)

Zong, Zheng; Wang, Xiaoping; Tian, Chongguo; Chen, Yingjun; Fu, Shanfei; Qu, Lin; Ji, Ling; Li, Jun; Zhang, Gan

2018-05-01

To apportion regional PM2.5 (atmospheric particles with aerodynamic diameter < 2.5 μm) source types and their geographic pattern in North China, 120 daily PM2.5 samples on Beihuangcheng Island (BH, a regional background site in North China) were collected from August 20th, 2014 to September 15th, 2015 showing one-year period. After the chemical analyses on carbonaceous species, water-soluble ions and inorganic elements, various approaches, such as Mann-Kendall test, chemical mass closure, ISORROPIA II model, Positive Matrix Factorization (PMF) linked with Potential Source Contribution Function (PSCF), were used to explore the PM2.5 speciation, sources, and source regions. Consequently, distinct seasonal variations of PM2.5 and its main species were found and could be explained by varying emission source characteristics. Based on PMF model, seven source factors for PM2.5 were identified, which were coal combustion + biomass burning, vehicle emission, mineral dust, ship emission, sea salt, industry source, refined chrome industry with the contribution of 48.21%, 30.33%, 7.24%, 6.63%, 3.51%, 3.2%, and 0.88%, respectively. In addition, PSCF analysis using the daily contribution of each factor from PMF result suggested that Shandong peninsula and Hebei province were identified as the high potential region for coal combustion + biomass burning; Beijing-Tianjin-Hebei (BTH) region was the main source region for industry source; Bohai Sea and East China Sea were found to be of high source potential for ship emission; Geographical region located northwest of BH Island was possessed of high probability for sea salt; Mineral dust presumably came from the region of Mongolia; Refined chrome industry mostly came from Liaoning, Jilin province; The vehicle emission was primarily of BTH region origin, centring on metropolises, such as Beijing and Tianjin. These results provided precious implications for PM2.5 control strategies in North China.

Concentrations and source apportionment of PM10 and associated elemental and ionic species in a lignite-burning power generation area of southern Greece.

PubMed

Argyropoulos, G; Grigoratos, Th; Voutsinas, M; Samara, C

2013-10-01

Ambient concentrations of PM10 and associated elemental and ionic species were measured over the cold and the warm months of 2010 at an urban and two rural sites located in the lignite-fired power generation area of Megalopolis in Peloponnese, southern Greece. The PM10 concentrations at the urban site (44.2 ± 33.6 μg m(-3)) were significantly higher than those at the rural sites (23.7 ± 20.4 and 22.7 ± 26.9 μg m(-3)). Source apportionment of PM10 and associated components was accomplished by an advanced computational procedure, the robotic chemical mass balance model (RCMB), using chemical profiles for a variety of local fugitive dust sources (power plant fly ash, flue gas desulfurization wet ash, feeding lignite, infertile material from the opencast mines, paved and unpaved road dusts, soil), which were resuspended and sampled through a PM10 inlet onto filters and then chemically analyzed, as well as of other common sources such as vehicular traffic, residential oil combustion, biomass burning, uncontrolled waste burning, marine aerosol, and secondary aerosol formation. Geological dusts (road/soil dust) were found to be major PM10 contributors in both the cold and warm periods of the year, with average annual contribution of 32.6 % at the urban site vs. 22.0 and 29.0 % at the rural sites. Secondary aerosol also appeared to be a significant source, contributing 22.1 % at the urban site in comparison to 30.6 and 28.7 % at the rural sites. At all sites, the contribution of biomass burning was most significant in winter (28.2 % at the urban site vs. 14.6 and 24.6 % at the rural sites), whereas vehicular exhaust contribution appeared to be important mostly in the summer (21.9 % at the urban site vs. 11.5 and 10.5 % at the rural sites). The highest contribution of fly ash (33.2 %) was found at the rural site located to the north of the power plants during wintertime, when winds are favorable. In the warm period, the highest contribution of fly ash was found at the rural site located to the south of the power plants, although it was less important (7.2 %). Moderate contributions of fly ash were found at the urban site (5.4 and 2.7 % in the cold and the warm period, respectively). Finally, the mine field was identified as a minor PM10 source, occasionally contributing with lignite dust and/or deposited wet ash dust under dry summer conditions, with the summertime contributions ranging between 3.1 and 11.0 % among the three sites. The non-parametric bootstrapped potential source contribution function analysis was further applied to localize the regions of sources apportioned by the RCMB. For the majority of sources, source regions appeared as being located within short distances from the sampling sites (within the Peloponnesse Peninsula). More distant Greek areas of the NNE sector also appeared to be source regions for traffic emissions and secondary calcium sulfate dust.

Effects of metals within ambient air particulate matter (PM) on human health.

PubMed

Chen, Lung Chi; Lippmann, Morton

2009-01-01

We review literature providing insights on health-related effects caused by inhalation of ambient air particulate matter (PM) containing metals, emphasizing effects associated with in vivo exposures at or near contemporary atmospheric concentrations. Inhalation of much higher concentrations, and high-level exposures via intratracheal (IT) instillation that inform mechanistic processes, are also reviewed. The most informative studies of effects at realistic exposure levels, in terms of identifying influential individual PM components or source-related mixtures, have been based on (1) human and laboratory animal exposures to concentrated ambient particles (CAPs), and (2) human population studies for which both health-related effects were observed and PM composition data were available for multipollutant regression analyses or source apportionment. Such studies have implicated residual oil fly ash (ROFA) as the most toxic source-related mixture, and Ni and V, which are characteristic tracers of ROFA, as particularly influential components in terms of acute cardiac function changes and excess short-term mortality. There is evidence that other metals within ambient air PM, such as Pb and Zn, also affect human health. Most evidence now available is based on the use of ambient air PM components concentration data, rather than actual exposures, to determine significant associations and/or effects coefficients. Therefore, considerable uncertainties about causality are associated with exposure misclassification and measurement errors. As more PM speciation data and more refined modeling techniques become available, and as more CAPs studies involving PM component analyses are performed, the roles of specific metals and other components within PM will become clearer.

Insights into the chemical characterization and sources of PM(2.5) in Beijing at a 1-h time resolution.

PubMed

Gao, Jian; Peng, Xing; Chen, Gang; Xu, Jiao; Shi, Guo-Liang; Zhang, Yue-Chong; Feng, Yin-Chang

2016-01-15

As the widespread application of online instruments penetrates the environmental fields, it is interesting to investigate the sources of fine particulate matter (PM2.5) based on the data monitored by online instruments. In this study, online analyzers with 1-h time resolution were employed to observe PM2.5 composition data, including carbon components, inorganic ions, heavy metals and gas pollutants, during a summer in Beijing. Chemical characteristics, temporal patterns and sources of PM2.5 are discussed. On the basis of hourly data, the mean concentration value of PM2.5 was 62.16±39.37 μg m(-3) (ranging from 6.69 to 183.67 μg m(-3)). The average concentrations of NO3(-), SO4(2-), NH4(+), OC and EC, the major chemical species, were 15.18±13.12, 14.80±14.53, 8.90±9.51, 9.32±4.16 and 3.08±1.43 μg m(-3), respectively. The concentration of PM2.5 varied during the online-sampling period, initially increasing and then subsequently decreasing. Three factor analysis models, including principal component analysis (PCA), positive matrix factorization (PMF) and Multilinear Engine 2 (ME2), were applied to apportion the PM2.5 sources. Source apportionment results obtained by the three different models were in agreement. Four sources were identified in Beijing during the sampling campaign, including secondary sources (38-39%), crustal dust (17-22%), vehicle exhaust (25-28%) and coal combustion (15-16%). Similar source profiles and contributions of PM2.5 were derived from ME2 and PMF, indicating the results of the two models are reasonable. The finding provides information that could be exploited for regular air control strategies. Copyright © 2015 Elsevier B.V. All rights reserved.

High-resolution sampling and analysis of air particulate matter in the Pear River Delta region of Southern China: source apportionment and health risk assessment

NASA Astrophysics Data System (ADS)

Zhou, S.; Day, P. K.; Wang, X.

2017-12-01

Hazardous air pollutants, such as trace elements in particulate matters (PM), are known or highly suspected to cause detrimental effects on human health. To understand the sources and associated risks of PM to human health, hourly time-integrated major trace elements in size-segregated coarse (PM10-2.5) and fine (PM2.5) particulate matter were collected and examined in an industrial city of Foshan in the Pearl River Delta region, China. Receptor modeling of the dataset by positive matrix factorization (PMF) was used to identify six sources contributing to PM2.5 and PM10 concentrations at the site. Dominant sources included industrial coal combustion, secondary inorganic aerosol, motor vehicles and construction dust along with two intermittent sources, biomass combustion and marine aerosol. The biomass combustion source was found to be a significant contributor to peak PM2.5 episodes along with motor vehicles and industrial coal combustion. Conditional probability function (CPF) was applied to estimate the local source effects from wind direction using the PMF-resolved source contribution coupled with the surface wind direction data. Health exposure risk for hazardous trace elements (Pb, As, Cr, Ni, Zn, V, Cu, Mn, Fe) and source-specific values were estimated. The total hazard quotient (total HQ =HI) of PM2.5 was 2.09, which is two times higher than the acceptable limit (HQ = 1). The total carcinogenic risk was 3.37*10-3 for PM2.5, which was three orders higher than the acceptable limit (i.e. 1.0*10-6). Among the selected trace elements, As and Pb posed the highest non-carcinogenic and carcinogenic risks for human health, respectively. In additional, our results showed that industrial coal combustion source was the dominant non-carcinogenic and carcinogenic risks contributor, highlighting the need for stringent control of this source. This study can provide new insight for policy makers to prioritize sources in air quality management and health risk reduction.

A framework for emissions source apportionment in industrial areas: MM5/CALPUFF in a near-field application.

PubMed

Ghannam, K; El-Fadel, M

2013-02-01

This paper examines the relative source contribution to ground-level concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), and PM10 (particulate matter with an aerodynamic diameter < 10 microm) in a coastal urban area due to emissions from an industrial complex with multiple stacks, quarrying activities, and a nearby highway. For this purpose, an inventory of CO, oxide of nitrogen (NO(x)), and PM10 emissions was coupled with the non-steady-state Mesoscale Model 5/California Puff Dispersion Modeling system to simulate individual source contributions under several spatial and temporal scales. As the contribution of a particular source to ground-level concentrations can be evaluated by simulating this single-source emissions or otherwise total emissions except that source, a set of emission sensitivity simulations was designed to examine if CALPUFF maintains a linear relationship between emission rates and predicted concentrations in cases where emitted plumes overlap and chemical transformations are simulated. Source apportionment revealed that ground-level releases (i.e., highway and quarries) extended over large areas dominated the contribution to exposure levels over elevated point sources, despite the fact that cumulative emissions from point sources are higher. Sensitivity analysis indicated that chemical transformations of NO(x) are insignificant, possibly due to short-range plume transport, with CALPUFF exhibiting a linear response to changes in emission rate. The current paper points to the significance of ground-level emissions in contributing to urban air pollution exposure and questions the viability of the prevailing paradigm of point-source emission reduction, especially that the incremental improvement in air quality associated with this common abatement strategy may not accomplish the desirable benefit in terms of lower exposure with costly emissions capping. The application of atmospheric dispersion models for source apportionment helps in identifying major contributors to regional air pollution. In industrial urban areas where multiple sources with different geometry contribute to emissions, ground-level releases extended over large areas such as roads and quarries often dominate the contribution to ground-level air pollution. Industrial emissions released at elevated stack heights may experience significant dilution, resulting in minor contribution to exposure at ground level. In such contexts, emission reduction, which is invariably the abatement strategy targeting industries at a significant investment in control equipment or process change, may result in minimal return on investment in terms of improvement in air quality at sensitive receptors.

Characterization of carbonaceous materials in PM2.5 and PM10 size fractions in Morogoro, Tanzania, during 2006 wet season campaign

NASA Astrophysics Data System (ADS)

Mkoma, Stelyus L.; Chi, Xuguang; Maenhaut, Willy

2010-05-01

Atmospheric aerosol samples in PM10 and PM2.5 size fractions were collected in parallel at a rural site in Morogoro during wet season in March and April 2006. All samples were analysed for the particulate matter mass, for organic, elemental, and total carbon (OC, EC, and TC), and for water-soluble OC (WSOC). The average PM10 and PM2.5 mass concentrations and associated standard deviations were 14 ± 13 μg/m 3 and 7.3 ± 4 μg/m 3 respectively. On average, TC accounted for 33% of the PM10 mass and 44% of the PM2.5 mass for the campaign. The average OC/PM percentage ratios were 27% and 33% in PM10 and PM2.5 size fractions respectively and a larger fraction of the OC was water-soluble. The observed low EC/TC mean percentage ratios of 10-14% respectively for PM10 and PM2.5 fractions indicate that the carbonaceous aerosol originates mainly from biogenic aerosols and/or biomass burning. A simple source apportionment approach was used to apportion the OC to biofuel and charcoal burning. On average, 93% of the PM10 OC was attributed to biofuel and 7% to charcoal burning in the 2006 wet season campaign. However, it is suggested that a contribution to the OC at Morogoro could also come from other natural biogenic matter, and/or biomass burning aerosols. The results for the sources of OC at Morogoro should therefore be considered with great caution.

Size distribution and source identification of total suspended particulate matter and associated heavy metals in the urban atmosphere of Delhi.

PubMed

Srivastava, Arun; Jain, V K

2007-06-01

A study of the atmospheric particulate size distribution of total suspended particulate matter (TSPM) and associated heavy metal concentrations has been carried out for the city of Delhi. Urban particles were collected using a five-stage impactor at six sites in three different seasons, viz. winter, summer and monsoon in the year 2001. Five samples from each site in each season were collected. Each sample (filter paper) was extracted with a mixture of nitric acid, hydrochloric acid and hydrofluoric acid. The acid solutions of the samples were analysed in five-particle fractions by atomic absorption spectrometry (AAS). The impactor stage fractionation of particles shows that a major portion of TSPM concentration is in the form of PM0.7 (i.e. <0.7microm). Similarly, the most of the metal mass viz. Mn, Cr, Cd, Pb, Ni, and Fe are also concentrated in the PM0.7 mode. The only exceptions are size distributions pertaining to Cu and Ca. Though, Cu is more in PM0.7 mode, its presence in size intervals 5.4-1.6microm and 1.6-0.7microm is also significant, whilst in case of Ca there is no definite pattern in its distribution with size of particles. The average PM10.9 (i.e. <10.9microm) concentrations are approximately 90.2%+/-4.5%, 81.4%+/-1.4% and 86.4%+/-9.6% of TSPM for winter, summer and monsoon seasons, respectively. Source apportionment reveals that there are two sources of TSPM and PM10.9, while three and four sources were observed for PM1.6 (i.e. <1.6microm) and PM0.7, respectively. Results of regression analyses show definite correlations between PM10.9 and other fine size fractions, suggesting PM10.9 may adequately act as a surrogate for both PM1.6 and PM0.7, while PM1.6 may adequately act as a surrogate for PM0.7.

Tracing carbonaceous sources by using particulate carbon and sulfate in precipitation in Calgary, Alberta Canada

NASA Astrophysics Data System (ADS)

Ge, C.; Stenhouse, K. J.; Du, K.; Xing, Z.; Norman, A. L.

2016-12-01

Carbonaceous matter is often the dominant contributor to Particulate Matter (PM) which has a significant influence on climate, air quality and human health. The measurement of particulate carbon in rainfall in Calgary, Alberta has not been studied. This study reports the sulfate and the first concentrations of particulate carbon (PC) in rainfall in Calgary. It traces seasonal carbonaceous sources for the purpose of understanding sources for air quality control. Precipitation samples are collected twice a day at the University of Calgary. Thermo-optical methods are used to analyze concentrations of PC, including elemental carbon (EC), primary organic carbon (POC) and secondary organic carbon (SOC). Sulfate concentrations are measured using ion chromatography. In this study, sources from long range transport and local emissions are examined. We emphasized the apportionment of OC/EC in oil and gas emissions and diurnal variations in transportation emissions. Weekly average data for dry deposition were calculated to estimate the scavenging ratio of EC/POC/SOC and ions in precipitation. The results of this study will be presented with an emphasis on the relationship of carbonaceous material and sulfate. A range of apportionment methods have been applied to examine limitations in quantifying SOC in fall.

Size distribution of chemical elements and their source apportionment in ambient coarse, fine, and ultrafine particles in Shanghai urban summer atmosphere.

PubMed

Lü, Senlin; Zhang, Rui; Yao, Zhenkun; Yi, Fei; Ren, Jingjing; Wu, Minghong; Feng, Man; Wang, Qingyue

2012-01-01

Ambient coarse particles (diameter 1.8-10 microm), fine particles (diameter 0.1-1.8 microm), and ultrafine particles (diameter < 0.1 microm) in the atmosphere of the city of Shanghai were sampled during the summer of 2008 (from Aug 27 to Sep 08). Microscopic characterization of the particles was investigated by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDX). Mass concentrations of Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr, and Pb in the size-resolved particles were quantified by using synchrotron radiation X-ray fluorescence (SRXRF). Source apportionment of the chemical elements was analyzed by means of an enrichment factor method. Our results showed that the average mass concentrations of coarse particles, fine particles and ultrafine particles in the summer air were 9.38 +/- 2.18, 8.82 +/- 3.52, and 2.02 +/- 0.41 microg/m3, respectively. The mass percentage of the fine particles accounted for 51.47% in the total mass of PM10, indicating that fine particles are the major component in the Shanghai ambient particles. SEM/EDX results showed that the coarse particles were dominated by minerals, fine particles by soot aggregates and fly ashes, and ultrafine particles by soot particles and unidentified particles. SRXRF results demonstrated that crustal elements were mainly distributed in the coarse particles, while heavy metals were in higher proportions in the fine particles. Source apportionment revealed that Si, K, Ca, Fe, Mn, Rb, and Sr were from crustal sources, and S, Cl, Cu, Zn, As, Se, Br, and Pb from anthropogenic sources. Levels of P, V, Cr, and Ni in particles might be contributed from multi-sources, and need further investigation.

Characterization of Arctic elemental carbon in Barrow, AK using radiocarbon source apportionment

NASA Astrophysics Data System (ADS)

Barrett, T. E.; Usenko, S.; Robinson, E. M.; Sheesley, R. J.

2013-12-01

Currently, the Arctic is one of the fastest warming regions on earth with surface temperatures increasing at a rate nearly double the global mean over recent decades. Despite the fact that atmospheric concentrations of elemental carbon (EC) are lower in the Arctic than in lower latitudes, deposition of EC on snow and ice may exacerbate regional warming by simultaneously decreasing albedo and increasing melt rates. Due to the intensifying Arctic oil exploration in areas such as the Beaufort and Chukchi seas, the impact of new emission sources such as heavy fuel and heavy diesel combustion on regional carbon needs to be assessed. The first step in developing mitigation strategies for reducing current and future EC emissions in the Arctic is to determine emission source contributions. This study aims to determine the relative contributions of fossil fuel and biomass combustion and to identify major source regions of EC to the Arctic. Radiocarbon analysis of both total organic carbon (TOC) and EC combined with organic tracer and back trajectory analysis has been applied to a set of wintertime coarse particulate matter (PM10) samples from Barrow, AK. Preliminary apportionment for January 2013 indicates roughly half of TOC is from biogenic/biomass burning emissions and one third of EC is due to biomass burning emissions. The radiocarbon results will be combined with organic tracer analysis (polycyclic aromatic hydrocarbons, petroleum biomarkers and normal alkanes), increasing the specificity of the relative contribution of both the fossil and modern (biogenic/biomass burning) carbon emission sources. This research represents the first reported radiocarbon values for Arctic EC, providing highly conclusive source apportionment prior to the influence of increased drilling operations and ship traffic in the Beaufort and Chukchi seas.

Seasonal changes, identification and source apportionment of PAH in PM1.0

NASA Astrophysics Data System (ADS)

Agudelo-Castañeda, Dayana Milena; Teixeira, Elba Calesso

2014-10-01

The objective of this research was to evaluate the seasonal variation of PAHs in PM1.0, as well as to identify and quantify the contributions of each source profile using the PMF receptor model. PM1.0 samples were collected on PTFE filters from August 2011 to July 2013 in the Metropolitan Area of Porto Alegre, Rio Grande do Sul, Brazil. The samples were extracted using the EPA method TO-13A and 16 Polycyclic Aromatic Hydrocarbons (PAHs) were analyzed using a gaseous chromatograph coupled with a mass spectrometer (GC-MS). Also, the data discussed in this study were analyzed to identify the relations of the PAHs concentrations with NOx, NO, O3 and meteorological parameters (temperature, solar radiation, wind speed, relative humidity). The results showed that in winter, concentrations of total PAHs were significantly higher than in summer, thus showing their seasonal variation. The identification of emission sources by applying diagnostic ratios confirmed that PAHs in the study area originate from mobile sources, especially, from diesel and gasoline emissions. The analysis by PMF receptor model showed the contribution of these two main sources of emissions, too, followed by coal combustion, incomplete combustion/unburned petroleum and wood combustion. The toxic equivalent factors were calculated to characterize the risk of cancer from PAH exposure to PM1.0 samples, and BaP and DahA dominated BaPeq levels.

Atmospheric particulate mercury in the megacity Beijing: Spatio-temporal variations and source apportionment

NASA Astrophysics Data System (ADS)

Schleicher, N. J.; Schäfer, J.; Blanc, G.; Chen, Y.; Chai, F.; Cen, K.; Norra, S.

2015-05-01

Particulate mercury (HgP) concentrations in weekly aerosol samples (PM2.5 and TSP) from Beijing, China, were measured for a complete year. In addition, spatial differences were measured for a shorter time period at four different sites and potential source materials were analyzed. Average HgP concentrations in PM2.5 samples were 0.26 ng/m3 for day-time PM2.5, 0.28 ng/m3 for night-time PM2.5, and 0.57 ng/m3 for TSP samples, respectively. Coal combustion was identified as the major source of HgP in Beijing. Other sources included industrial activities as well as red color on historical buildings as a minor contribution. Spatial differences were pronounced with highest concentrations in the inner city (inside the 3rd ring road). The results further showed a strong seasonality with highest concentrations in winter and lowest in summer due to local meteorological conditions (precipitation in summer and stagnant conditions and low mixing layer height in winter) as well as seasonal sources, such as coal combustion for heating purposes. Day-night differences also showed a seasonal pattern with higher night-time concentrations during summer and higher day-time concentrations during winter. Compared to other cities worldwide, the HgP concentrations in Beijing were alarmingly high, suggesting that airborne particulate Hg should be the focus of future monitoring activities and mitigation measures.

Atmospheric Aerosol Source-Receptor Relationships: The Role of Coal-Fired Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen L. Robinson; Spyros N. Pandis; Cliff I. Davidson

2005-12-01

This report describes the technical progress made on the Pittsburgh Air Quality Study (PAQS) during the period of March 2005 through August 2005. Significant progress was made this project period on the source characterization, source apportionment, and deterministic modeling activities. This report highlights new data on road dust, vegetative detritus and motor vehicle emissions. For example, the results show significant differences in the composition in urban and rural road dust. A comparison of the organic of the fine particulate matter in the tunnel with the ambient provides clear evidence of the significant contribution of vehicle emissions to ambient PM. Themore » source profiles developed from this work are being used by the source-receptor modeling activities. The report presents results on the spatial distribution of PMF-factors. The results can be grouped into three different categories: regional sources, local sources, or potentially both regional and local sources. Examples of the regional sources are the sulfate and selenium PMF-factors which most likely-represent coal fired power plants. Examples of local sources are the specialty steel and lead factors. There is reasonable correspondence between these apportionments and data from the EPA TRI and AIRS emission inventories. Detailed comparisons between PMCAMx predictions and measurements by the STN and IMPROVE measurements in the Eastern US are presented. Comparisons were made for the major aerosol components and PM{sub 2.5} mass in July 2001, October 2001, January 2002, and April 2002. The results are encouraging with average fraction biases for most species less than 0.25. The improvement of the model performance during the last two years was mainly due to the comparison of the model predictions with the continuous measurements in the Pittsburgh Supersite. Major improvements have included the descriptions: of ammonia emissions (CMU inventory), night time nitrate chemistry, EC emissions and their diurnal variation, and nitric acid dry removal.« less

Receptor modeling of PM2.5, PM10 and TSP in different seasons and long-range transport analysis at a coastal site of Tianjin, China.

PubMed

Kong, Shaofei; Han, Bin; Bai, Zhipeng; Chen, Li; Shi, Jianwu; Xu, Zhun

2010-09-15

Atmospheric particulate matter (PM(2.5), PM(10) and TSP) were sampled synchronously during three monitoring campaigns from June 2007 to February 2008 at a coastal site in TEDA of Tianjin, China. Chemical compositions including 19 elements, 6 water-solubility ions, organic and elemental carbon were determined. principle components analysis (PCA) and chemical mass balance modeling (CMB) were applied to determine the PM sources and their contributions with the assistance of NSS SO(4)(2)(-), the mass ratios of NO(3)(-) to SO(4)(2)(-) and OC to EC. Air mass backward trajectory model was compared with source apportionment results to evaluate the origin of PM. Results showed that NSS SO(4)(2)(-) values for PM(2.5) were 2147.38, 1701.26 and 239.80 ng/m(3) in summer, autumn and winter, reflecting the influence of sources from local emissions. Most of it was below zero in summer for PM(10) indicating the influence of sea salt. The ratios of NO(3)(-) to SO(4)(2)(-) was 0.19 for PM(2.5), 0.18 for PM(10) and 0.19 for TSP in winter indicating high amounts of coal consumed for heating purpose. Higher OC/EC values (mostly larger than 2.5) demonstrated that secondary organic aerosol was abundant at this site. The major sources were construction activities, road dust, vehicle emissions, marine aerosol, metal manufacturing, secondary sulfate aerosols, soil dust, biomass burning, some pharmaceutics industries and fuel-oil combustion according to PCA. Coal combustion, marine aerosol, vehicular emission and soil dust explained 5-31%, 1-13%, 13-44% and 3-46% for PM(2.5), PM(10) and TSP, respectively. Backward trajectory analysis showed air parcels originating from sea accounted for 39% in summer, while in autumn and winter the air parcels were mainly related to continental origin. Copyright 2010 Elsevier B.V. All rights reserved.

Characterization of emissions from South Asian biofuels and application to source apportionment of carbonaceous aerosol in the Himalayas

NASA Astrophysics Data System (ADS)

Stone, Elizabeth A.; Schauer, James J.; Pradhan, Bidya Banmali; Dangol, Pradeep Man; Habib, Gazala; Venkataraman, Chandra; Ramanathan, V.

2010-03-01

This study focuses on improving source apportionment of carbonaceous aerosol in South Asia and consists of three parts: (1) development of novel molecular marker-based profiles for real-world biofuel combustion, (2) application of these profiles to a year-long data set, and (3) evaluation of profiles by an in-depth sensitivity analysis. Emissions profiles for biomass fuels were developed through source testing of a residential stove commonly used in South Asia. Wood fuels were combusted at high and low rates, which corresponded to source profiles high in organic carbon (OC) or high in elemental carbon (EC), respectively. Crop wastes common to the region, including rice straw, mustard stalk, jute stalk, soybean stalk, and animal residue burnings, were also characterized. Biofuel profiles were used in a source apportionment study of OC and EC in Godavari, Nepal. This site is located in the foothills of the Himalayas and was selected for its well-mixed and regionally impacted air masses. At Godavari, daily samples of fine particulate matter (PM2.5) were collected throughout the year of 2006, and the annual trends in particulate mass, OC, and EC followed the occurrence of a regional haze in South Asia. Maximum concentrations occurred during the dry winter season and minimum concentrations occurred during the summer monsoon season. Specific organic compounds unique to aerosol sources, molecular markers, were measured in monthly composite samples. These markers implicated motor vehicles, coal combustion, biomass burning, cow dung burning, vegetative detritus, and secondary organic aerosol as sources of carbonaceous aerosol. A molecular marker-based chemical mass balance (CMB) model provided a quantitative assessment of primary source contributions to carbonaceous aerosol. The new profiles were compared to widely used biomass burning profiles from the literature in a sensitivity analysis. This analysis indicated a high degree of stability in estimates of source contributions to OC when different biomass profiles were used. The majority of OC was unapportioned to primary sources and was estimated to be of secondary origin, while biomass combustion was the next-largest source of OC. The CMB apportionment of EC to primary sources was unstable due to the diversity of biomass burning conditions in the region. The model results suggested that biomass burning and fossil fuel were important contributors to EC, but could not reconcile their relative contributions.

Chemical characterization of fine particulate matter in Changzhou, China, and source apportionment with offline aerosol mass spectrometry

NASA Astrophysics Data System (ADS)

Ye, Zhaolian; Liu, Jiashu; Gu, Aijun; Feng, Feifei; Liu, Yuhai; Bi, Chenglu; Xu, Jianzhong; Li, Ling; Chen, Hui; Chen, Yanfang; Dai, Liang; Zhou, Quanfa; Ge, Xinlei

2017-02-01

Knowledge of aerosol chemistry in densely populated regions is critical for effective reduction of air pollution, while such studies have not been conducted in Changzhou, an important manufacturing base and populated city in the Yangtze River Delta (YRD), China. This work, for the first time, performed a thorough chemical characterization on the fine particulate matter (PM2.5) samples, collected during July 2015 to April 2016 across four seasons in this city. A suite of analytical techniques was employed to measure the organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), water-soluble inorganic ions (WSIIs), trace elements, and polycyclic aromatic hydrocarbons (PAHs) in PM2.5; in particular, an Aerodyne soot particle aerosol mass spectrometer (SP-AMS) was deployed to probe the chemical properties of water-soluble organic aerosol (WSOA). The average PM2.5 concentration was found to be 108.3 µg m-3, and all identified species were able to reconstruct ˜ 80 % of the PM2.5 mass. The WSIIs occupied about half of the PM2.5 mass (˜ 52.1 %), with SO42-, NO3-, and NH4+ as the major ions. On average, nitrate concentrations dominated over sulfate (mass ratio of 1.21), indicating that traffic emissions were more important than stationary sources. OC and EC correlated well with each other and the highest OC / EC ratio (5.16) occurred in winter, suggesting complex OC sources likely including both secondary and primary ones. Concentrations of eight trace elements (Mn, Zn, Al, B, Cr, Cu, Fe, Pb) can contribute up to ˜ 5.0 % of PM2.5 during winter. PAH concentrations were also high in winter (140.25 ng m-3), which were predominated by median/high molecular weight PAHs with five and six rings. The organic matter including both water-soluble and water-insoluble species occupied ˜ 21.5 % of the PM2.5 mass. SP-AMS determined that the WSOA had average atomic oxygen-to-carbon (O / C), hydrogen-to-carbon (H / C), nitrogen-to-carbon (N / C), and organic matter-to-organic carbon (OM / OC) ratios of 0.54, 1.69, 0.11, and 1.99, respectively. Source apportionment of WSOA further identified two secondary OA (SOA) factors (a less oxidized and a more oxidized oxygenated OA) and two primary OA (POA) factors (a nitrogen-enriched hydrocarbon-like traffic OA and a local primary OA likely including species from cooking, coal combustion, etc.). On average, the POA contribution outweighed SOA (55 % vs. 45 %), indicating the important role of local anthropogenic emissions in the aerosol pollution in Changzhou. Our measurement also shows the abundance of organic nitrogen species in WSOA, and the source analyses suggest these species are likely associated with traffic emissions, which warrants more investigations on PM samples from other locations.

Impact of secondary inorganic aerosol and road traffic at a suburban air quality monitoring station.

PubMed

Megido, L; Negral, L; Castrillón, L; Fernández-Nava, Y; Suárez-Peña, B; Marañón, E

2017-03-15

PM10 from a suburban site in the northwest of Spain was assessed using data from chemical determinations, meteorological parameters, aerosol maps and five-day back trajectories of air masses. Temporal variations in the chemical composition of PM10 were subsequently related to stationary/mobile local sources and long-range transport stemming from Europe and North Africa. The presence of secondary inorganic species (sulphates, nitrates and ammonium) in airborne particulate matter constituted one of the main focuses of this study. These chemical species formed 16.5% of PM10 on average, in line with other suburban background sites in Europe. However, a maximum of 47.8% of PM10 were recorded after several days under the influence of European air masses. Furthermore, the highest values of these three chemical species coincided with episodes of poor air circulation and influxes of air masses from Europe. The relationship between SO 4 2- and NH 4 + (R 2  = 0.57, p-value<0.01) was found to improve considerably in summer and spring (R 2  = 0.88 and R 2  = 0.87, respectively, p-value<0.01), whereas NO 3 - and NH 4 + (R 2  = 0.55, p-value<0.01) reproduced this pattern in winter (R 2  = 0.91, p-value<0.01). The application of a receptor model to the dataset led to the identification of notable apportionments due to road traffic and other types of combustion processes. In fact, large amounts of particulate matter were released to the atmosphere during episodes of biomass burning in forest fires. On isolated days, combustion was estimated to contribute up to 21.0 μg PM/m 3 (50.8% of PM10). The contribution from industrial processes to this source is also worth highlighting given the presence of Ni and Co in its profile. Furthermore, African dust outbreaks at the sampling site, characterised by an arc through the Atlantic Ocean, were usually associated with a higher concentration of Al 2 O 3 in PM10. Results evidenced the relevance of stationary (i.e., steelworks and thermal power station) and mobile sources in the air quality at the suburban site under study, with important apportionments of particulate matter coming from road traffic and as consequence of releasing precursor gases of secondary particles to the atmosphere. Copyright © 2016 Elsevier Ltd. All rights reserved.

Resuspension of soil as a source of airborne lead near industrial facilities and highways.

PubMed

Young, Thomas M; Heeraman, Deo A; Sirin, Gorkem; Ashbaugh, Lowell L

2002-06-01

Geologic materials are an important source of airborne particulate matter less than 10 microm aerodynamic diameter (PM10), but the contribution of contaminated soil to concentrations of Pb and other trace elements in air has not been documented. To examine the potential significance of this mechanism, surface soil samples with a range of bulk soil Pb concentrations were obtained near five industrial facilities and along roadsides and were resuspended in a specially designed laboratory chamber. The concentration of Pb and other trace elements was measured in the bulk soil, in soil size fractions, and in PM10 generated during resuspension of soils and fractions. Average yields of PM10 from dry soils ranged from 0.169 to 0.869 mg of PM10/g of soil. Yields declined approximately linearly with increasing geometric mean particle size of the bulk soil. The resulting PM10 had average Pb concentrations as high as 2283 mg/kg for samples from a secondary Pb smelter. Pb was enriched in PM10 by 5.36-88.7 times as compared with uncontaminated California soils. Total production of PM10 bound Pb from the soil samples varied between 0.012 and 1.2 mg of Pb/kg of bulk soil. During a relatively large erosion event, a contaminated site might contribute approximately 300 ng/m3 of PM10-bound Pb to air. Contribution of soil from contaminated sites to airborne element balances thus deserves consideration when constructing receptor models for source apportionment or attempting to control airborne Pb emissions.

Apportionment of urban aerosol sources in Chongqing (China) using synergistic on-line techniques

NASA Astrophysics Data System (ADS)

Chen, Yang; Yang, Fumo

2016-04-01

The sources of ambient fine particulate matter (PM2.5) during wintertime at a background urban location in Chongqing (southwestern China) have been determined. Aerosol chemical composition analyses were performed using multiple on-line techniques, such as single particle aerosol mass spectrometer (SPAMS) for single particle chemical composition, on-line elemental carbon-organic carbon analyzer (on-line OC-EC), on-line X-ray fluorescence (XRF) for elements, and in-situ Gas and Aerosol Compositions monitor (IGAC) for water-soluble ions in PM2.5. All the datasets from these techniques have been adjusted to a 1-h time resolution for receptor model input. Positive matrix factorization (PMF) has been used for resolving aerosol sources. At least six sources, including domestic coal burning, biomass burning, dust, traffic, industrial and secondary/aged factors have been resolved and interpreted. The synergistic on-line techniques were helpful for identifying aerosol sources more clearly than when only employing the results from the individual techniques. This results are useful for better understanding of aerosol sources and atmospheric processes.

Urban air quality in a mid-size city - PM2.5 composition, sources and identification of impact areas: From local to long range contributions

NASA Astrophysics Data System (ADS)

Squizzato, Stefania; Cazzaro, Marta; Innocente, Elena; Visin, Flavia; Hopke, Philip K.; Rampazzo, Giancarlo

2017-04-01

Urban air quality represents a major public health burden and is a long-standing concern to European citizens. Combustion processes and traffic-related emissions represent the main primary particulate matter (PM) sources in urban areas. Other sources can also affect air quality (e.g., secondary aerosol, industrial) depending on the characteristics of the study area. Thus, the identification and the apportionment of all sources is of crucial importance to make effective corrective decisions within environmental policies. The aim of this study is to evaluate the impacts of different emissions sources on PM2.5 concentrations and compositions in a mid-size city in the Po Valley (Treviso, Italy). Data have been analyzed to highlight compositional differences (elements and major inorganic ions), to determine PM2.5 sources and their contributions, and to evaluate the influence of air mass movements. Non-parametric tests, positive matrix factorization (PMF), conditional bivariate probability function (CBPF), and concentration weighted trajectory (CWT) have been used in a multi-chemometrics approach to understand the areal-scale (proximate, local, long-range) where different sources act on PM2.5 levels and composition. Results identified three levels of scale from which the pollution arose: (i) a proximate local scale (close to the sampling site) for traffic non-exhaust and resuspended dust sources; (ii) a local urban scale (including both sampling site and areas close to them) for combustion and industrial; and (iii) a regional scale characterized by ammonium nitrate and ammonium sulfate. This approach and results can help to develop and adopt better air quality policy action.

Combustion aerosols: factors governing their size and composition and implications to human health.

PubMed

Lighty, J S; Veranth, J M; Sarofim, A F

2000-09-01

Particulate matter (PM) emissions from stationary combustion sources burning coal, fuel oil, biomass, and waste, and PM from internal combustion (IC) engines burning gasoline and diesel, are a significant source of primary particles smaller than 2.5 microns (PM2.5) in urban areas. Combustion-generated particles are generally smaller than geologically produced dust and have unique chemical composition and morphology. The fundamental processes affecting formation of combustion PM and the emission characteristics of important applications are reviewed. Particles containing transition metals, ultrafine particles, and soot are emphasized because these types of particles have been studied extensively, and their emissions are controlled by the fuel composition and the oxidant-temperature-mixing history from the flame to the stack. There is a need for better integration of the combustion, air pollution control, atmospheric chemistry, and inhalation health research communities. Epidemiology has demonstrated that susceptible individuals are being harmed by ambient PM. Particle surface area, number of ultrafine particles, bioavailable transition metals, polycyclic aromatic hydrocarbons (PAH), and other particle-bound organic compounds are suspected to be more important than particle mass in determining the effects of air pollution. Time- and size-resolved PM measurements are needed for testing mechanistic toxicological hypotheses, for characterizing the relationship between combustion operating conditions and transient emissions, and for source apportionment studies to develop air quality plans. Citations are provided to more specialized reviews, and the concluding comments make suggestions for further research.

Source apportionment of Beijing air pollution during a severe winter haze event and associated pro-inflammatory responses in lung epithelial cells

NASA Astrophysics Data System (ADS)

Liu, Qingyang; Baumgartner, Jill; Zhang, Yuanxun; Schauer, James J.

2016-02-01

Air pollution is a leading risk factor for the disease burden in China and globally. Few epidemiologic studies have characterized the particulate matter (PM) components and sources that are most responsible for adverse health outcomes, particularly in developing countries. In January 2013, a severe haze event occurred over 25 days in urban Beijing, China. Ambient fine particulate matter (PM2.5) was collected at a central urban site in Beijing from January 16-31, 2013. We analyzed the samples for water soluble ions, metals, elemental carbon (EC), organic carbon (OC), and individual organic molecular markers including n-alkanes, hopanes, PAHs and sterols. Chemical components were used to quantify the source contributions to PM2.5 using the chemical mass balance (CMB) model by the conversion of the OC estimates combined with inorganic secondary components (e.g. NH4+, SO42-, NO3-). Water extracts of PM were exposed to lung epithelial cells, and supernatants recovered from cell cultures were assayed for the pro-inflammatory cytokines by a quantitative ELLSA method. Linear regression models were used to estimate the associations between PM sources and components with pro-inflammatory responses in lung epithelial cells following 24-hrs and 48-hrs of exposure. The largest contributors to PM2.5 during the monitoring period were inorganic secondary ions (53.2% and 54.0% on haze and non-haze days, respectively). Other organic matter (OM) contributed to a larger proportion of PM2.5 during haze days (16.9%) compared with non-haze days (12.9%), and coal combustion accounted for 10.9% and 8.7% on haze and non-haze days, respectively. We found PM2.5 mass and specific sources (e.g. coal combustion, traffic emission, dust, other OM, and inorganic secondary ions) were highly associated with inflammatory responses of lung epithelial cells. Our results showed greater responses in the exposure to 48-hr PM2.5 mass and its sources compared to 24-hr PM exposure, and that secondary and coal combustion sources play an important role in short-term inflammation and require cost-effective policy to control their contributions to air pollution.

Source apportionment of carbonaceous chemical species to fossil fuel combustion, biomass burning and biogenic emissions by a coupled radiocarbon-levoglucosan marker method

NASA Astrophysics Data System (ADS)

Salma, Imre; Németh, Zoltán; Weidinger, Tamás; Maenhaut, Willy; Claeys, Magda; Molnár, Mihály; Major, István; Ajtai, Tibor; Utry, Noémi; Bozóki, Zoltán

2017-11-01

An intensive aerosol measurement and sample collection campaign was conducted in central Budapest in a mild winter for 2 weeks. The online instruments included an FDMS-TEOM, RT-OC/EC analyser, DMPS, gas pollutant analysers and meteorological sensors. The aerosol samples were collected on quartz fibre filters by a low-volume sampler using the tandem filter method. Elemental carbon (EC), organic carbon (OC), levoglucosan, mannosan, galactosan, arabitol and mannitol were determined, and radiocarbon analysis was performed on the aerosol samples. Median atmospheric concentrations of EC, OC and PM2.5 mass were 0.97, 4.9 and 25 µg m-3, respectively. The EC and organic matter (1.6 × OC) accounted for 4.8 and 37 %, respectively, of the PM2.5 mass. Fossil fuel (FF) combustion represented 36 % of the total carbon (TC = EC + OC) in the PM2.5 size fraction. Biomass burning (BB) was a major source (40 %) for the OC in the PM2.5 size fraction, and a substantial source (11 %) for the PM10 mass. We propose and apply here a novel, straightforward, coupled radiocarbon-levoglucosan marker method for source apportionment of the major carbonaceous chemical species. The contributions of EC and OC from FF combustion (ECFF and OCFF) to the TC were 11.0 and 25 %, respectively, EC and OC from BB (ECBB and OCBB) were responsible for 5.8 and 34 %, respectively, of the TC, while the OC from biogenic sources (OCBIO) made up 24 % of the TC. The overall relative uncertainty of the OCBIO and OCBB contributions was assessed to be up to 30 %, while the relative uncertainty for the other apportioned species is expected to be below 20 %. Evaluation of the apportioned atmospheric concentrations revealed some of their important properties and relationships among them. ECFF and OCFF were associated with different FF combustion sources. Most ECFF was emitted by vehicular road traffic, while the contribution of non-vehicular sources such as domestic and industrial heating or cooking using gas, oil or coal to OCFF was substantial. The mean contribution of BB to EC particles was smaller by a factor of approximately 2 than that of road traffic. The main formation processes of OCFF, OCBB and OCBIO from volatile organic compounds were jointly influenced by a common factor, which is most likely the atmospheric photochemistry, while primary organic emissions can also be important. Technological improvements and control measures for various BB appliances, together with efficient education and training of their users, in particular on the admissible fuel types, offer an important potential for improving the air quality in Budapest, and likely in other cities as well.

Source apportionment of PM2.5 nitrate and sulfate in China using a source-oriented chemical transport model

NASA Astrophysics Data System (ADS)

Zhang, Hongliang; Li, Jingyi; Ying, Qi; Yu, Jian Zhen; Wu, Dui; Cheng, Yuan; He, Kebin; Jiang, Jingkun

2012-12-01

Nitrate and sulfate account for a significant fraction of PM2.5 mass and are generally secondary in nature. Contributions to these two inorganic aerosol components from major sources need to be identified for policy makers to develop cost effective regional emission control strategies. In this work, a source-oriented version of the Community Multiscale Air Quality (CMAQ) model that directly tracks the contributions from multiple emission sources to secondary PM2.5 is developed to determine the regional contributions of power, industry, transportation and residential sectors as well as biogenic sources to nitrate and sulfate concentrations in China in January and August 2009.The source-oriented CMAQ model is capable of reproducing most of the available PM10 and PM2.5 mass, and PM2.5 nitrate and sulfate observations. Model prediction suggests that monthly average PM2.5 inorganic components (nitrate + sulfate + ammonium ion) can be as high as 60 μg m-3 in January and 45 μg m-3 in August, accounting for 20-40% and 50-60% of total PM2.5 mass. The model simulations also indicate significant spatial and temporal variation of the nitrate and sulfate concentrations as well as source contributions in the country. In January, nitrate is high over Central and East China with a maximum of 30 μg m-3 in the Sichuan Basin. In August, nitrate is lower and the maximum concentration of 16 μg m-3 occurs in North China. In January, highest sulfate occurs in the Sichuan Basin with a maximum concentration of 18 μg m-3 while in August high sulfate concentration occurs in North and East China with a similar maximum concentration. Power sector is the dominating source of nitrate and sulfate in both January and August. Transportation sector is an important source of nitrate (20-30%) in both months. Industry sector contributes to both nitrate and sulfate concentrations by approximately 20-30%. Residential sector contributes to approximately 10-20% of nitrate and sulfate in January but its contribution is low in August.

Insights into PM10 sources in Houston, Texas: Role of petroleum refineries in enriching lanthanoid metals during episodic emission events

NASA Astrophysics Data System (ADS)

Bozlaker, Ayşe; Buzcu-Güven, Birnur; Fraser, Matthew P.; Chellam, Shankararaman

2013-04-01

Petroleum refineries may emit large quantities of pollutants during non-routine operations that include start-ups and shutdowns, planned maintenance, and unplanned equipment failures. The Texas Commission on Environmental Quality (TCEQ) tracks such events by requiring industries to self-report estimates of these emissions because they often have a detrimental impact on local air quality and potentially, public health. An inventory of non-routine episodic emission events is available via TCEQ's website. However, there is on-going concern that such episodic emissions are sometimes under-reported or even not cataloged. Herein, we present concentrations of 42 main group, transition, and lanthanoid elements in 114 time-resolved (3 or 6 h) samples collected over a 1-month period. We also develop strategies to identify aerosol sources using elemental tracers and compare source apportionment (performed by positive matrix factorization) based on ambient measurements to inventoried non-routine emission events. Through interpretation of key marker elements, five sources impacting concentrations of metals in PM10 were identified and calculated to contribute 73% of the measured PM10 mass. On average, primary emissions from fluidized-bed catalytic cracking (FCC) units negligibly contributed to apportioned PM10 mass. However, 35 samples were identified as impacted by transient PM10 emissions from FCC units because of elevated levels of lanthanoid metals and their ratios. Only 31 of these 35 samples coincided with self-reported non-routine emission events. Further, roughly half of the emission event self-reports detailed only emissions of gaseous pollutants. Based on this, we posit that not all PM10 emission events are reported and even self-reported emission events are incomplete - those that only catalog gaseous pollutants may also include unreported PM emissions.

PM2.5 source apportionment in a French urban coastal site under steelworks emission influences using constrained non-negative matrix factorization receptor model.

PubMed

Kfoury, Adib; Ledoux, Frédéric; Roche, Cloé; Delmaire, Gilles; Roussel, Gilles; Courcot, Dominique

2016-02-01

The constrained weighted-non-negative matrix factorization (CW-NMF) hybrid receptor model was applied to study the influence of steelmaking activities on PM2.5 (particulate matter with equivalent aerodynamic diameter less than 2.5 μm) composition in Dunkerque, Northern France. Semi-diurnal PM2.5 samples were collected using a high volume sampler in winter 2010 and spring 2011 and were analyzed for trace metals, water-soluble ions, and total carbon using inductively coupled plasma--atomic emission spectrometry (ICP-AES), ICP--mass spectrometry (ICP-MS), ionic chromatography and micro elemental carbon analyzer. The elemental composition shows that NO3(-), SO4(2-), NH4(+) and total carbon are the main PM2.5 constituents. Trace metals data were interpreted using concentration roses and both influences of integrated steelworks and electric steel plant were evidenced. The distinction between the two sources is made possible by the use Zn/Fe and Zn/Mn diagnostic ratios. Moreover Rb/Cr, Pb/Cr and Cu/Cd combination ratio are proposed to distinguish the ISW-sintering stack from the ISW-fugitive emissions. The a priori knowledge on the influencing source was introduced in the CW-NMF to guide the calculation. Eleven source profiles with various contributions were identified: 8 are characteristics of coastal urban background site profiles and 3 are related to the steelmaking activities. Between them, secondary nitrates, secondary sulfates and combustion profiles give the highest contributions and account for 93% of the PM2.5 concentration. The steelwork facilities contribute in about 2% of the total PM2.5 concentration and appear to be the main source of Cr, Cu, Fe, Mn, Zn. Copyright © 2015. Published by Elsevier B.V.

Characterization of atmospheric black carbon and co-pollutants in urban and rural areas of Spain

NASA Astrophysics Data System (ADS)

Becerril-Valle, M.; Coz, E.; Prévôt, A. S. H.; Močnik, G.; Pandis, S. N.; Sánchez de la Campa, A. M.; Alastuey, A.; Díaz, E.; Pérez, R. M.; Artíñano, B.

2017-11-01

A one-year black carbon (BC) experimental study was performed at three different locations (urban traffic, urban background, rural) in Spain with different equivalent BC (eBC) source characteristics by means of multi-wavelength Aethalometers. The Aethalometer model was used for the source apportionment study, based on the difference in absorption spectral dependence of emissions from biomass burning (bb) and fossil fuel (ff) combustion. Most studies use a single bb and ff absorption Ångström exponent (AAE) pair (AAEbb and AAEff), however in this work we use a range of AAE values associated with fossil fuel and biomass burning based on the available measurements, which represents more properly all conditions. A sensitivity analysis of the source specific AAE was carried out to determine the most appropriate AAE values, being site dependent and seasonally variable. Here we present a methodology for the determination of the ranges of AAEbb and AAEff by evaluating the correlations between the source apportionment of eBC using the Aethalometer model with four biomass burning tracers measured at the rural site. The best combination was AAEbb = [1.63-1.74] and AAEff = [0.97-1.12]. Mean eBC values (±SD) obtained during the period of study were 3.70 ± 3.73 μg m-3 at the traffic urban site, 2.33 ± 2.96 μg m-3 at the urban background location, and 2.61 ± 5.04 μg m-3 in the rural area. High contributions of eBC to the PM10 mass were found (values up to 21% in winter), but with high eBC/PM10 variability. The hourly mean eBCff and eBCbb concentrations varied from 0 to 51 μg m-3 and from 0 to 50 μg m-3 at the three sites, respectively, exhibiting distinct seasonal and daily patterns. The fossil fuel combustion was the dominant eBC source at the urban sites, while biomass burning dominated during the cold season (88% of eBCbb) in the rural area. Daily PM2.5 and PM10 samples were collected using high-volume air samplers and analyzed for OC and EC. Analysis of biomass burning tracers and organic (OC) and elemental (EC) carbon in the rural area indicate that biomass combustion is the main source, while OC and EC indicate a lower influence of this source at the urban site.

Sources of ambient concentrations and chemical composition of PM 2.5-0.1 in Cork Harbour, Ireland

NASA Astrophysics Data System (ADS)

Hellebust, S.; Allanic, A.; O'Connor, I. P.; Jourdan, C.; Healy, D.; Sodeau, J. R.

2010-02-01

Particulate matter (PM 10-2.5 and PM 2.5-0.1) has been collected over a period of one year in Cork Harbour, Ireland, using a high-volume cascade impactor and polyurethane foam collection substrate. Collected PM 2.5-0.1 was analysed for water-soluble inorganic ions and metal content using ion chromatography and inductively coupled plasma-optical emission spectroscopy. On average approximately 50% by mass of the chemical content of PM was identified. The motivation for the study was to assess the potential impact of shipping emissions on air quality in Cork Harbour and City, with a view to informing public health impacts. The average ambient concentration of PM 10 between May 2007 and April 2008 was 4.6 µgm - 3 and the maximum concentration measured in one sample, representing a 4 day collection period, was 16 µgm - 3 . The major inorganic constituents identified in PM collected in Haulbowline Island in Cork Harbour were sulfate, ammonium, nitrate, chloride and sodium ions, which were mainly attributable to sea salt and secondary inorganic aerosols from regional sources. The results were analysed by principal component analysis for the purpose of source apportionment. Four factors were identified explaining over 80% of the data set variance. The factors were: shipping, sea salt, crustal material and secondary inorganic aerosols (SIA). The smaller size fraction was frequently observed to dominate, as the average concentration was 2.77 µgm - 3 for PM 2.5-0.1 compared to 1.9 µgm - 3 for PM 10-2.5. Fresh ship plumes were not found to make a significant contribution to primary PM 2.5-0.1 concentrations adjacent to the shipping channel. However, this was partially attributed to the ultrafine nature of ship emissions and the majority of the toxic metal content was attributed to emissions associated with heavy oil combustion sources, which include ship engines.

Constrained Source Apportionment of Coarse Particulate Matter and Selected Trace Elements in Three Cities from the Multi-Ethnic Study of Atherosclerosis

PubMed Central

Sturtz, Timothy M.; Adar, Sara D.; Gould, Timothy; Larson, Timothy V.

2016-01-01

PM10-2.5 mass and trace element concentrations were measured in Winston-Salem, Chicago, and St. Paul at up to 60 sites per city during two different seasons in 2010. Positive Matrix Factorization (PMF) was used to explore the underlying sources of variability. Information on previously reported PM10-2.5 tire and brake wear profiles was used to constrain these features in PMF by prior specification of selected species ratios. We also modified PMF to allow for combining the measurements from all three cities into a single model while preserving city-specific soil features. Relatively minor differences were observed between model predictions with and without the prior ratio constraints, increasing confidence in our ability to identify separate brake wear and tire wear features. Brake wear, tire wear, fertilized soil, and re-suspended soil were found to be important sources of copper, zinc, phosphorus, and silicon respectively across all three urban areas. PMID:27468256

Constrained source apportionment of coarse particulate matter and selected trace elements in three cities from the multi-ethnic study of atherosclerosis

NASA Astrophysics Data System (ADS)

Sturtz, Timothy M.; Adar, Sara D.; Gould, Timothy; Larson, Timothy V.

2014-02-01

PM10-2.5 mass and trace element concentrations were measured in Winston-Salem, Chicago, and St. Paul at up to 60 sites per city during two different seasons in 2010. Positive Matrix Factorization (PMF) was used to explore the underlying sources of variability. Information on previously reported PM10-2.5 tire and brake wear profiles was used to constrain these features in PMF by prior specification of selected species ratios. We also modified PMF to allow for combining the measurements from all three cities into a single model while preserving city-specific soil features. Relatively minor differences were observed between model predictions with and without the prior ratio constraints, increasing confidence in our ability to identify separate brake wear and tire wear features. Brake wear, tire wear, fertilized soil, and resuspended soil were found to be important sources of copper, zinc, phosphorus, and silicon, respectively, across all three urban areas.

Chemical characterization and source apportionment of fine and coarse particulate matter in Lahore, Pakistan

NASA Astrophysics Data System (ADS)

Stone, Elizabeth; Schauer, James; Quraishi, Tauseef A.; Mahmood, Abid

2010-03-01

Lahore, Pakistan is an emerging megacity that is heavily polluted with high levels of particle air pollution. In this study, respirable particulate matter (PM 2.5 and PM 10) were collected every sixth day in Lahore from 12 January 2007 to 19 January 2008. Ambient aerosol was characterized using well-established chemical methods for mass, organic carbon (OC), elemental carbon (EC), ionic species (sulfate, nitrate, chloride, ammonium, sodium, calcium, and potassium), and organic species. The annual average concentration (±one standard deviation) of PM 2.5 was 194 ± 94 μg m -3 and PM 10 was 336 ± 135 μg m -3. Coarse aerosol (PM 10-2.5) was dominated by crustal sources like dust (74 ± 16%, annual average ± one standard deviation), whereas fine particles were dominated by carbonaceous aerosol (organic matter and elemental carbon, 61 ± 17%). Organic tracer species were used to identify sources of PM 2.5 OC and chemical mass balance (CMB) modeling was used to estimate relative source contributions. On an annual basis, non-catalyzed motor vehicles accounted for more than half of primary OC (53 ± 19%). Lesser sources included biomass burning (10 ± 5%) and the combined source of diesel engines and residual fuel oil combustion (6 ± 2%). Secondary organic aerosol (SOA) was an important contributor to ambient OC, particularly during the winter when secondary processing of aerosol species during fog episodes was expected. Coal combustion alone contributed a small percentage of organic aerosol (1.9 ± 0.3%), but showed strong linear correlation with unidentified sources of OC that contributed more significantly (27 ± 16%). Brick kilns, where coal and other low quality fuels are burned together, are suggested as the most probable origins of unapportioned OC. The chemical profiling of emissions from brick kilns and other sources unique to Lahore would contribute to a better understanding of OC sources in this megacity.

Source insights into the 11-h daytime and nighttime fine ambient particulate matter in China as well as the synthetic studies using the new Multilinear Engine 2-species ratios (ME2-SR) method.

PubMed

Shi, Guoliang; Chen, Gang; Liu, Guirong; Wang, Haiting; Tian, Yingze; Feng, Yinchang

2016-10-01

Modeled results are very important for environmental management. Unreasonable modeled result can lead to wrong strategy for air pollution management. In this work, an improved physically constrained source apportionment (PCSA) technology known as Multilinear Engine 2-species ratios (ME2-SR) was developed to the 11-h daytime and nighttime fine ambient particulate matter in urban area. Firstly, synthetic studies were carried out to explore the effectiveness of ME2-SR. The estimated source contributions were compared with the true values. The results suggest that, compared with the positive matrix factorization (PMF) model, the ME2-SR method could obtain more physically reliable outcomes, indicating that ME2-SR was effective, especially when apportioning the datasets with no unknown source. Additionally, 11-h daytime and nighttime PM2.5 samples were collected from Tianjin in China. The sources of the 11-h daytime and nighttime fine ambient particulate matter in China were identified using the new method and the PMF model. The calculated source contributions for ME2-SR for daytime PM2.5 samples are resuspended dust (38.91 μg m(-3), 26.60%), sulfate and nitrate (38.60 μg m(-3), 26.39%), vehicle exhaust and road dust (38.26 μg m(-3), 26.16%) and coal combustion (20.14 μg m(-3), 13.77%), and those for nighttime PM2.5 samples are resuspended dust (18.78 μg m(-3), 12.91%), sulfate and nitrate (41.57 μg m(-3), 28.58%), vehicle exhaust and road dust (38.39 μg m(-3), 26.39%), and coal combustion (36.76 μg m(-3), 25.27%). The comparisons of the constrained versus unconstrained outcomes clearly suggest that the physical meaning of the ME2-SR results is interpretable and reliable, not only for the specified species values but also for source contributions. The findings indicate that the ME2-SR method can be a useful tool in source apportionment studies, for air pollution management. Copyright © 2016 Elsevier Ltd. All rights reserved.

Source of Personal Exposure to PM2.5 among College Students in Beijing, China

NASA Astrophysics Data System (ADS)

Xie, Qiaorong; Zhu, Xianlei; Li, Xiang; Hui, Fan; Fu, Xianqiang; Zhang, Qiangbin

2015-04-01

The health risk from exposure to airborne particles arouses increasing public concern in Beijing, a megacity in China, where concentration of PM2.5 frequently exceeds the guideline values of World Health Organization (WHO). To investigate daily exposure to PM2.5, a personal exposure study was conducted for college students. The purpose of this study was to measure the daily PM2.5 personal exposures of students, to quantify the contributions of various microenvironments to personal exposure since students spend more than 85% of their time indoors, and to apportion the contributions of PM2.5 indoors origin and outdoor origin. In this work, a total of 320 paired indoor and outdoor PM2.5 samples were collected at eight types of microenvironments in both China University of Petroleum (suburban area) and Tsinghua University (urban area). The microenvironments were selected based on the time-activity diary finished by 1500 students from both universities. Simultaneously, the air exchange rate was measured in each microenvironment. PM2.5, elements, inorganic ions and polycyclic aromatic hydrocarbons in the samples were determined. The peak concentrations were observed in dinning halls, whereas PM2.5 in dormitories was the largest contributor to personal exposure because students spend more than half of a day there. Furthermore, source apportionment by positive matrix factorization (PMF) will be carried out to understand the source of personal exposure to PM2.5. Especially, efforts will be put on determing the contributions of primary combustion, secondary sulfate and organics, secondary nitrate, and mechanically generated PM, which present different infiltration behavior and are indoor PM2.5 of ambient origin, with help of air exchange rate data. The results would be benefit for refining the understanding of the contribution of PM2.5 of ambient (outdoor) origin to the daily PM2.5 personal exposures. Acknowledgments:This study has been funded by Beijing Municipal Commission of Education. Corresponding author:Qiangbin Zhang

Spatial and temporal source apportionment of PM2.5 in Georgia, 2002 to 2013

NASA Astrophysics Data System (ADS)

Zhai, Xinxin; Mulholland, James A.; Russell, Armistead G.; Holmes, Heather A.

2017-07-01

The Chemical Mass Balance (CMB) receptor model was applied to estimate PM2.5 source impacts over Georgia from 2002 to 2013 using ambient PM2.5 species concentration data from 13 sites. Measurements of 19 PM2.5 species were used as inputs along with measurement-based source profiles to estimate the impacts of nine sources, including both primary components (from heavy duty diesel vehicle, light duty gasoline vehicle, biomass burning, coal combustion, and suspended dust sources) and secondary pollutants (ammonium sulfate, ammonium bisulfate, ammonium nitrate, and secondary organic carbon). From 2002 to 2013, PM2.5 total mass decreased from 13.8 μg/m3 to 9.2 μg/m3 averaged across all sites, a 33% decrease. Largest decreases were observed for secondary sulfate and nitrate species (58% and 44%, respectively). The amount of neutralization by ammonium did not change substantially over the time period in spite of substantial decreases in sulfate and nitrate concentrations. Total mobile source impacts decreased more at urban sites (39%) than rural sites (23%), whereas biomass burning decreased more at rural sites (34%) than urban sites (27%). The estimated central-site source impacts are found to spatially represent large areas for secondary pollutants, smaller areas for biomass burning and dust, and very local areas for mobile sources and coal combustion. Trends from the National Emissions Inventory were compared with the annual trends of mobile source impacts, coal combustion impacts, and sulfate concentrations, resulting in statistically significant positive trends with Pearson R2 of 0.80, 0.64, and 0.79, respectively. Results presented here suggest that PM2.5 reductions in Georgia and the Southeast have been achieved by control of both stationary and mobile sources, and that PM2.5 is comprised of increasing fractions of biomass burning emissions and suspended dust. The temporal trends of source impacts at each site adds information about source changes beyond the every-three-year emission inventories for evaluation of emission-based model results.

Source apportionment and heavy metal health risk (HMHR) quantification from sources in a southern city in China, using an ME2-HMHR model.

PubMed

Peng, Xing; Shi, GuoLiang; Liu, GuiRong; Xu, Jiao; Tian, YingZe; Zhang, YuFen; Feng, YinChang; Russell, Armistead G

2017-02-01

Heavy metals (Cr, Co, Ni, As, Cd, and Pb) can be bound to PM adversely affecting human health. Quantifying the source impacts on heavy metals can provide source-specific estimates of the heavy metal health risk (HMHR) to guide effective development of strategies to reduce such risks from exposure to heavy metals in PM 2.5 (particulate matter (PM) with aerodynamic diameter less than or equal to 2.5 μm). In this study, a method combining Multilinear Engine 2 (ME2) and a risk assessment model is developed to more effectively quantify source contributions to HMHR, including heavy metal non-cancer risk (non-HMCR) and cancer risk (HMCR). The combined model (called ME2-HMHR) has two steps: step1, source contributions to heavy metals are estimated by employing the ME2 model; step2, the source contributions in step 1 are introduced into the risk assessment model to calculate the source contributions to HMHR. The approach was applied to Huzou, China and five significant sources were identified. Soil dust is the largest source of non-HMCR. For HMCR, the source contributions of soil dust, coal combustion, cement dust, vehicle, and secondary sources are 1.0 × 10 -4 , 3.7 × 10 -5 , 2.7 × 10 -6 , 1.6 × 10 -6 and 1.9 × 10 -9 , respectively. The soil dust is the largest contributor to HMCR, being driven by the high impact of soil dust on PM 2.5 and the abundance of heavy metals in soil dust. Copyright © 2016 Elsevier Ltd. All rights reserved.

Regional evaluation of particulate matter composition in an Atlantic coastal area (Cantabria region, northern Spain): Spatial variations in different urban and rural environments

NASA Astrophysics Data System (ADS)

Arruti, A.; Fernández-Olmo, I.; Irabien, A.

2011-07-01

The aim of this study was to determine the major components (Na, Ca, K, Mg, Fe, Al, NH 4+, SO 42-, NO 3-, Cl - and TC) and trace-metal levels (As, Ni, Cd, Pb, Ti, V, Cr, Mn, Cu, Mo, Rh and Hg) in PM 10 and PM 2.5 at an Atlantic coastal city (Santander, Cantabria region, Northern Spain). Additional samples were collected in other urban sites of the Cantabria region to assess the metal content found in different urban environments within the region. To control for the mass attributed to inland regional background particulate matter, samples were also collected in Los Tojos village. The spatial variability of the major PM components shows that PM origins are different at inland and coastal sites. In the coastal city of Santander, the most important contributors are (i) the marine aerosol and (ii) the secondary inorganic aerosol (SIA) and the total carbon (TC) in PM 10 and PM 2.5, respectively. Additionally, the influence of the coastal location on the ionic balance of PM is also studied. The trace metal spatial variability is studied using the coefficient of divergence (COD), which shows that the levels of trace metals at the three studied urban sites are mainly influenced by local emission sources. The main local tracers are identified as follows: Mn in the Santander area; Mo, Cr and Pb at Reinosa; and Ni and V at Castro Urdiales. A more detailed source apportionment study of the local trace metals at Santander is conducted by Principal Component Analysis (PCA) and Positive Matrix Factorisation (PMF); these two receptor models report complementary information. From these statistical analyses, the identified sources of trace metals in PM 10 are urban background sources, industrial sources and traffic. The industrial factor was dominated by Mn, Cu and Pb, which are trace metals used in steel production and manganese-ferroalloy production plant. With respect to PM 2.5, the identified emission sources of trace metals are combustion processes as well as traffic and industrial sources.

Overview of the Lombardy Region (I) Source Apportionment Study

NASA Astrophysics Data System (ADS)

Larsen, B. R.

2009-04-01

The Lombardia Region (RL) is situated in the central part of the Po Plain (I) where the mesoscale climatological conditions are determined to a high degree by the orographical characteristics of this area. Encirclement from three sides (North, West and South) by the mountain chains contributes greatly to the climatological peculiarities that are related from the physical point of view to the dynamic of the air mass in this region. The adverse anemological regime and the persistence of atmospheric stability result in low wind speeds, inversion of the temperature, and shallow inversion layers. Due to these particular geographical and the meteorological conditions associated with a high population density (9 million inhabitants) and the connected anthropogenic activities, RL is one of Europe's most polluted regions with regard to PM and photochemical smog. The 24 hours EU air quality limit for PM10 of 50 ug/m3 is exceeded up to 180 days per year and the yearly limit of 40 ug/m3 is in breach for most urban/urban background areas. In order to efficiently plan abatement strategies, quantitative information is required on the pollution sources and available emission inventories need to be compared with source apportionment results derived by receptor modeling of the chemical composition of PM10 in ambient air and in source emissions. The European Commission Joint Research Centre (JRC) has embarked on a major integrated project in RL (2006-2010) in collaboration with the air quality authorities (ARPA) to support the design of appropriate air quality and emission reduction strategies in this area. The present paper presents the first results of this project, carried out during typical winter episodes in 2007 at ten measurement stations distributed over the entire RL. The source contributions to PM10 and the associated air toxics (benzo[a]pyrene, Pb, Ni, Cd and As) have been quantified by Chemical Mass Balance and Positive Matrix Factorization based upon the chemical analysis of 700 filters including the bulk compounds OC, EC, nitrate, sulfate and ammonium together with a number of source marker compounds such as levoglucosan, K, Rb, PAH (wood combustion); linear alkanes (fuel/biogenic emissions); (Fe, Cu, Sn, Sb, and Mo (break-ware); Ce, Rh, Pt, and Pd (vehicle exhaust catalysts), Ca, Al, Fe, Mg, K, Ti, Ce, and Sr (soil/dust re-suspension), Na, Cl (road salt); V and Ni (fuel oil); Zn (tire-ware/tire combustion); Fe, Mn, Cr (railroad steel abrasion). The 76 ± 33 ug/m3 average PM10 concentration over the whole region was apportioned into ‘Secondary Aerosol - mostly inorganics' (30-40%), 'Transport - including re-suspension' (30-40%), and 'Residential Heating - mostly wood burning' (10-18% - 28% in Sondrio) and shows that reduction of industrial emissions of inorganic gaseous PM precursors should not be left out of the regions PM abatement strategy. Minor specific sources were also revealed. A detailed presentation will be given of the obtained data and results for the nine sites in the Po Valley in comparison with the site in the Valtelline Valley (Sondrio).

Spatial variability of trace elements and sources for improved exposure assessment in Barcelona

NASA Astrophysics Data System (ADS)

Minguillón, María Cruz; Cirach, Marta; Hoek, Gerard; Brunekreef, Bert; Tsai, Ming; de Hoogh, Kees; Jedynska, Aleksandra; Kooter, Ingeborg M.; Nieuwenhuijsen, Mark; Querol, Xavier

2014-06-01

Trace and major elements concentrations in PM10 and PM2.5 were measured at 20 sites spread in the Barcelona metropolitan area (1 rural background, 6 urban background, 13 road traffic sites) and at 1 reference site. Three 2-week samples per site and size fraction were collected during 2009 using low volume samplers, adding a total of 120 samples. Collected samples were analysed for elemental composition using Energy Dispersive X-ray fluorescence (XRF). EC, OC, and hopanes and steranes concentrations in PM2.5 were determined. Positive Matrix Factorisation (PMF) model was used for a source apportionment analysis. The work was performed as part of the ESCAPE project. Elements were found in concentrations within the usual range in Spanish urban areas. Mineral elements were measured in higher concentrations during the warm season, due to enhanced resuspension; concentrations of fueloil combustion elements were also higher in summer. Elements in higher concentration at the traffic sites were: Ba, Cr, Cu, Fe, Mn, Mo, Pb, Sn, Zn and Zr. Spatial variations related to non-traffic sources were observed for concentrations of Br, Cl, K, and Na (sea salt origin) and Ni, V and S (shipping emissions), which were higher at the coastal sites, as well as for Zn and Pb, higher at sites closer to industrial facilities. Five common sources for PM10 and PM2.5 were identified by PMF: road traffic (with tracers Ba, Cr, Cu, Fe, Mo and Zn); fueloil combustion (Ni and V); secondary sulphate; industry (Pb and Zn); and mineral source (Al, Ca, Mg, Si, Sr and Ti). A marine aerosol source, a mixture of sea salt with aged anthropogenic aerosols, was found only in PM10. EC, hopanes and steranes concentrations correlate strongly with the PM10 road traffic source contributions, being hence all attributed to the same source. OC may arise from other sources in addition to road traffic and have a high contribution of secondary OC. Significant spatial and temporal variation in the PM2.5 and PM10 elemental composition was found. Spatial patterns differed per element, related to the main source. The identified source contributions can be used in health studies of source-specific particles.

Coarse particle (PM10-2.5) source profiles for emissions from domestic cooking and industrial process in Central India.

PubMed

Bano, Shahina; Pervez, Shamsh; Chow, Judith C; Matawle, Jeevan Lal; Watson, John G; Sahu, Rakesh Kumar; Srivastava, Anjali; Tiwari, Suresh; Pervez, Yasmeen Fatima; Deb, Manas Kanti

2018-06-15

To develop coarse particle (PM 10-2.5 , 2.5 to 10μm) chemical source profiles, real-world source sampling from four domestic cooking and seven industrial processing facilities were carried out in "Raipur-Bhilai" of Central India. Collected samples were analysed for 32 chemical species including 21 elements (Al, As, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, S, Sb, Se, V, and Zn) by atomic absorption spectrophotometry (AAS), 8 water-soluble ions (Na + , K + , Mg 2+ , Ca 2+ , Cl - , F - , NO 3 - , and SO 4 2- ) by ion chromatography, ammonium (NH 4 + ) by spectrophotometry, and carbonaceous fractions (OC and EC) by thermal/optical transmittance. The carbonaceous fractions were most abundant fraction in household fuel and municipal solid waste combustion emissions while elemental species were more abundant in industrial emissions. Most of the elemental species were enriched in PM 2.5 (<2.5μm) size fraction as compared to the PM 10-2.5 fraction. Abundant Ca (13-28%) was found in steel-rolling mill (SRM) and cement production industry (CPI) emissions, with abundant Fe (14-32%) in ferro-manganese (FEMNI), steel production industry (SPI), and electric-arc welding emissions. High coefficients of divergence (COD) values (0.46 to 0.88) among the profiles indicate their differences. These region-specific source profiles are more relevant to source apportionment studies in India than profiles measured elsewhere. Copyright © 2018. Published by Elsevier B.V.

Markers and influence of open biomass burning on atmospheric particulate size and composition during a major bonfire event

NASA Astrophysics Data System (ADS)

Vassura, Ivano; Venturini, Elisa; Marchetti, Sara; Piazzalunga, Andrea; Bernardi, Elena; Fermo, Paola; Passarini, Fabrizio

2014-01-01

This study aims to characterize PM from the open burning of bonfires as well as detect a series of useful tracer species for source apportionment studies. Total suspended particulate (TSP), PM10 and PM2.5 were collected before, during, and after St. Joseph's Eve (18th of March). On this day, several bonfires are lit throughout the study area. Levoglucosan (Lvg), OC, EC, PAHs, soluble ions, and some metals (Al, Cd, Cu, Ni, and Pb) have been determined in each fraction. Results show that the contamination of the area is similar to what is generally found in suburban areas. The fine fraction makes the highest contribution to PM. This fraction is mainly related to compounds composing the PM secondarily formed, while the coarser fractions are associated with natural matrices. The bonfire event is an important source of particulate. All the combustion markers determined in PM2.5 (EC, OC, PAHs (except for Flu and Pyr), K+, Cl-, and Lvg) register a higher concentration. Lvg/OC ratio confirms higher wood smoke emissions during these days. Both the concentration and the compound profile indicate a different origin of PAHs in the atmosphere. The highest concentration of K+ and OC in TSP confirm the contribution of open fire, as well, to this fraction, which can be ascribable mainly to combustion ash. Nitrates and sulphates also show a higher concentration in the PM10-TSP fraction. Surprisingly, there is also an increase in the concentration of components not usually considered combustion markers, i.e. Pb and Al in PM2.5. This is probably ascribable to their bioaccumulation. In conclusion, Lvg, OC, PAHs, Al, and Pb can be used together as specific markers of bonfires to identify this source of particulate matter.

Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): Emissions of particulate matter from garbage burning, wood and dung cooking fires, motorcycles and brick kilns

NASA Astrophysics Data System (ADS)

Jayarathne, T. S.; Rathnayake, C.; Stockwell, C.; Daugherty, K.; Islam, R. M.; Christian, T. J.; Bhave, P.; Praveen, P. S.; Panday, A. K.; Adhikari, S.; Rasmi, M.; Goetz, D.; DeCarlo, P. F.; Saikawa, E.; Yokelson, R. J.; Stone, E. A.

2016-12-01

The Nepal Ambient Monitoring and Source Testing Experiment (NAMASTE) field campaign targeted the in-situ characterization of widespread and under-sampled combustion sources in South Asia by determining emission factors (EF) for fine particulate matter (PM2.5), organic carbon (OC), elemental carbon, inorganic ions, trace metals, and organic species. Garbage burning had the highest EF PM2.5 among the sampled sources ranging 7-124 g kg-1, with maximum EFs for garbage burned under higher moisture conditions. Garbage burning emissions contained high concentrations of polycyclic aromatic compounds (PAHs) and heavy metals (Pb, Cd, Zn) that are associated with acute and chronic health effects. Triphenylbenzene and antimony (Sb) were unique to garbage burning are good candidates for tracing this source. Cook stove emissions varied largely by stove technology (traditional mud stove, 3-stone cooking fire, chimney stove, etc.) and biomass fuel (dung, hardwood, twigs, and mixtures thereof). Burning dung consistently emitted more PM2.5 than burning wood and contained characteristic fecal sterols and stanols. Motorcycle emissions were evaluated before and after servicing, which decreased EF PM2.5 from 8.8 g kg-1 to 0.7 g kg-1. Organic species analysis indicated that this reduction in PM2.5­ is largely due to a decrease in emission of motor oil. For brick kilns, the forced draft zig-zag kilns had higher EF PM2.5 (12-19 g kg-1) compared to clamp kilns (8-13 g kg-1) and also exhibited chemical differences. PM2.5 emitted from the zig-zag kiln were mainly OC (7%), sulfate (32%) and uncharacterized chemical components (60%), while clamp kiln emissions were dominated by OC (64%) and ammonium sulfate (36%). The quantitative emission factors developed in this study may be used for source apportionment and to update regional emission inventories.

Characterization and source apportionment of PM2.5-bound polycyclic aromatic hydrocarbons from Shanghai city, China.

PubMed

Wang, Qing; Liu, Min; Yu, Yingpeng; Li, Ye

2016-11-01

Polycyclic aromatic hydrocarbons (PAHs) were studied in 230 daily fine particulate matter (PM2.5) samples collected in four seasons at urban and suburban sites of Shanghai, China. This study focused on the emission sources of PAHs and its dynamic results under different weather conditions and pollution levels and also emphasized on the spatial sources of PM2.5 and PAHs at a regional level. Annual concentrations of PM2.5 and 16 EPA priority PAHs were 53 μg/m 3 and 6.9 ng/m 3 , respectively, with highest levels in winter. Positive matrix factorization (PMF) modeling identified four sources of PAHs: coal combustion, traffic, volatilization and biomass combustion, and coking, with contributions of 34.9%, 27.5%, 21.1% and 16.5%, respectively. The contribution of traffic, a local-indicative source, increased from 17.4% to 28.7% when wind speed changed from >2m/s to <2m/s, and increased from 18.3% to 31.3% when daily PAH concentrations changed from below to above the annual mean values. This indicated that local sources may have larger contributions under stagnant weather when poorer dispersion conditions and lower wind speed led to the accumulation of local-emitted pollutants. The trajectory clustering and potential source contribution function (PSCF) and concentration weighted trajectory (CWT) models showed clearly that air parcels moved from west had highest concentrations of PM2.5, total PAHs and high molecular weight (HMW) PAHs. While small differences were found among all five clusters in low molecular weight (LMW) PAHs. Sector analyses determined that regional transport source contributed 39.8% to annual PM2.5 and 52.5% to PAHs, mainly from western regions and varying with seasons. This work may make contribution to a better understanding and control of the increasingly severe air pollution in China as well as other developing Asian countries. Copyright © 2016 Elsevier Ltd. All rights reserved.

Application of an integrated Weather Research and Forecasting (WRF)/CALPUFF modeling tool for source apportionment of atmospheric pollutants for air quality management: A case study in the urban area of Benxi, China.

PubMed

Wu, Hao; Zhang, Yan; Yu, Qi; Ma, Weichun

2018-04-01

In this study, the authors endeavored to develop an effective framework for improving local urban air quality on meso-micro scales in cities in China that are experiencing rapid urbanization. Within this framework, the integrated Weather Research and Forecasting (WRF)/CALPUFF modeling system was applied to simulate the concentration distributions of typical pollutants (particulate matter with an aerodynamic diameter <10 μm [PM 10 ], sulfur dioxide [SO 2 ], and nitrogen oxides [NO x ]) in the urban area of Benxi. Statistical analyses were performed to verify the credibility of this simulation, including the meteorological fields and concentration fields. The sources were then categorized using two different classification methods (the district-based and type-based methods), and the contributions to the pollutant concentrations from each source category were computed to provide a basis for appropriate control measures. The statistical indexes showed that CALMET had sufficient ability to predict the meteorological conditions, such as the wind fields and temperatures, which provided meteorological data for the subsequent CALPUFF run. The simulated concentrations from CALPUFF showed considerable agreement with the observed values but were generally underestimated. The spatial-temporal concentration pattern revealed that the maximum concentrations tended to appear in the urban centers and during the winter. In terms of their contributions to pollutant concentrations, the districts of Xihu, Pingshan, and Mingshan all affected the urban air quality to different degrees. According to the type-based classification, which categorized the pollution sources as belonging to the Bengang Group, large point sources, small point sources, and area sources, the source apportionment showed that the Bengang Group, the large point sources, and the area sources had considerable impacts on urban air quality. Finally, combined with the industrial characteristics, detailed control measures were proposed with which local policy makers could improve the urban air quality in Benxi. In summary, the results of this study showed that this framework has credibility for effectively improving urban air quality, based on the source apportionment of atmospheric pollutants. The authors endeavored to build up an effective framework based on the integrated WRF/CALPUFF to improve the air quality in many cities on meso-micro scales in China. Via this framework, the integrated modeling tool is accurately used to study the characteristics of meteorological fields, concentration fields, and source apportionments of pollutants in target area. The impacts of classified sources on air quality together with the industrial characteristics can provide more effective control measures for improving air quality. Through the case study, the technical framework developed in this study, particularly the source apportionment, could provide important data and technical support for policy makers to assess air pollution on the scale of a city in China or even the world.

Single particle mass spectral signatures from vehicle exhaust particles and the source apportionment of on-line PM2.5 by single particle aerosol mass spectrometry.

PubMed

Yang, Jian; Ma, Shexia; Gao, Bo; Li, Xiaoying; Zhang, Yanjun; Cai, Jing; Li, Mei; Yao, Ling'ai; Huang, Bo; Zheng, Mei

2017-09-01

In order to accurately apportion the many distinct types of individual particles observed, it is necessary to characterize fingerprints of individual particles emitted directly from known sources. In this study, single particle mass spectral signatures from vehicle exhaust particles in a tunnel were performed. These data were used to evaluate particle signatures in a real-world PM 2.5 apportionment study. The dominant chemical type originating from average positive and negative mass spectra for vehicle exhaust particles are EC species. Four distinct particle types describe the majority of particles emitted by vehicle exhaust particles in this tunnel. Each particle class is labeled according to the most significant chemical features in both average positive and negative mass spectral signatures, including ECOC, NaK, Metal and PAHs species. A single particle aerosol mass spectrometry (SPAMS) was also employed during the winter of 2013 in Guangzhou to determine both the size and chemical composition of individual atmospheric particles, with vacuum aerodynamic diameter (d va ) in the size range of 0.2-2μm. A total of 487,570 particles were chemically analyzed with positive and negative ion mass spectra and a large set of single particle mass spectra was collected and analyzed in order to identify the speciation. According to the typical tracer ions from different source types and classification by the ART-2a algorithm which uses source fingerprints for apportioning ambient particles, the major sources of single particles were simulated. Coal combustion, vehicle exhaust, and secondary ion were the most abundant particle sources, contributing 28.5%, 17.8%, and 18.2%, respectively. The fraction with vehicle exhaust species particles decreased slightly with particle size in the condensation mode particles. Copyright © 2017 Elsevier B.V. All rights reserved.

Source apportionment of size-fractionated particles during the 2013 Asian Youth Games and the 2014 Youth Olympic Games in Nanjing, China.

PubMed

Chen, Pulong; Wang, Tijian; Lu, Xiaobo; Yu, Yiyong; Kasoar, Matthew; Xie, Min; Zhuang, Bingliang

2017-02-01

In this study, samples of size-fractionated particulate matter were collected continuously using a 9-size interval cascade impactor at an urban site in Nanjing, before, during and after the Asian Youth Games (AYG), from July to September of 2013, and the Youth Olympic Games (YOG), from July to September of 2014. First, elemental concentrations, water-soluble ions including Cl - , NO 3 - , SO 4 2- , NH 4 + , K + , Na + and Ca 2+ , organic carbon (OC) and elemental carbon (EC) were analysed. Then, the source apportionment of the fine and coarse particulate matter was carried out using the chemical mass balance (CMB) model. The average PM 10 concentrations were 90.4±20.0μg/m 3 during the 2013 AYG and 70.6±25.3μg/m 3 during the 2014 YOG. For PM 2.1, the average concentrations were 50.0±12.8μg/m 3 in 2013 and 34.6±17.0μg/m 3 in 2014. Investigations showed that the average concentrations of particles declined significantly from 2013 to 2014, and concentrations were at the lowest levels during the events. Results indicated that OC, EC, sulfate and crustal elements have significant monthly and size-based variations. The major components, including crustal elements, water-soluble ions and carbonaceous aerosol accounted for 75.3-91.9% of the total particulate mass concentrations during the sampling periods. Fugitive dust, coal combustion dust, iron dust, construction dust, soil dust, vehicle exhaust, secondary aerosols and sea salt have been classified as the main emissions in Nanjing. The source apportionment results indicate that the emissions from fugitive dust, which was the most abundance emission source during the 2013 AYG, contributed to 23.0% of the total particle mass. However, fugitive dust decreased to 6.2% of the total particle mass during the 2014 YOG. Construction dust (14.7% versus 7.8% for the AYG and the YOG, respectively) and secondary sulfate aerosol (9.3% versus 8.0% for the AYG and the YOG, respectively) showed the same trend as fugitive dust, suggesting that the mitigation measures of controlling particles from the paved roads, construction and industry worked more efficiently during the YOG. Copyright © 2016 Elsevier B.V. All rights reserved.

Development and Application of Novel Sampling Methodologies for Study of Volatile Particulate Matter in Military Aircraft Emissions

DTIC Science & Technology

2012-09-01

experiments. J. Aerosol Sci., 40, 603- 612. Zheng, M., Cass, G. R., Schauer, J. J., Edgerton, E. S. (2002) Source Apportionment of PM2.5 in the...Energy Heavy Vehicle Research Program. The SERDP project WP1627 team consists of the following members (listed in alphabetical order of the last name...aircraft emissions are dominated by a fleet of high payload aircraft, such as the C-130, B1 B-52, and a variety of heavy -lift turboshaft vehicles

Chemical characterization and receptor modeling of PM10 in the surroundings of the opencast lignite mines of Western Macedonia, Greece.

PubMed

Samara, Constantini; Argyropoulos, George; Grigoratos, Theodoros; Kouras, Αthanasios; Manoli, Εvangelia; Andreadou, Symela; Pavloudakis, Fragkiskos; Sahanidis, Chariton

2018-05-01

The Western Macedonian Lignite Center (WMLC) in northwestern Greece is the major lignite center in the Balkans feeding four major power plants of total power exceeding 4 GW. Concentrations of PM 10 (i.e., particulate matters with diameters ≤10 μm) are the main concern in the region, and the high levels observed are often attributed to the activities related to power generation. In this study, the contribution of fugitive dust emissions from the opencast lignite mines to the ambient levels of PM 10 in the surroundings was estimated by performing chemical mass balance (CMB) receptor modeling. For this purpose, PM 10 samples were concurrently collected at four receptor sites located in the periphery of the mine area during the cold and the warm periods of the year (November-December 2011 and August-September 2012), and analyzed for a total of 26 macro- and trace elements and ionic species (sulfate, nitrate, chloride). The robotic chemical mass balance (RCMB) model was employed for source identification/apportionment of PM 10 at each receptor site using as inputs the ambient concentrations and the chemical profiles of various sources including the major mine operations, the fly ash escaping the electrostatic filters of the power plants, and other primary and secondary sources. Mean measured PM 10 concentrations at the different sites ranged from 38 to 72 μg m -3 . The estimated total contribution of mines ranged between 9 and 22% in the cold period increasing to 36-42% in the dry warm period. Other significant sources were vehicular traffic, biomass burning, and secondary sulfate and nitrate aerosol. These results imply that more efficient measures to prevent and suppress fugitive dust emissions from the mines are needed.

Chemical composition and source apportionment of PM2.5 during Chinese Spring Festival at Xinxiang, a heavily polluted city in North China: Fireworks and health risks

NASA Astrophysics Data System (ADS)

Feng, Jinglan; Yu, Hao; Su, Xianfa; Liu, Shuhui; Li, Yi; Pan, Yuepeng; Sun, Jian-Hui

2016-12-01

Twenty-four PM2.5 samples were collected at a suburban site of Xinxiang during Chinese Spring Festival (SF) in 2015. 10 water-soluble ions, 19 trace elements and 8 fractions of carbonaceous species in PM2.5 were analyzed. Potential sources of PM2.5 were quantitatively apportioned using principal component analysis (PCA)-multivariate linear regressions (MLR). The threat of heavy metals in PM2.5 was assessed using incremental lifetime cancer risk (ILCR). During the whole period, serious regional haze pollution persisted, the average concentration of PM2.5 was 111 ± 54 μg m- 3, with 95.8% and 79.2% of the daily samples exhibiting higher PM2.5 concentrations than the national air quality standard I and II. Chemical species declined due to holiday effect with the exception of K, Fe, Mg, Al and K+, Cl-, which increased on Chinese New Year (CNY)'s Eve and Lantern Festival in 2015, indicating the injection of firework burning particles in certain short period. PM2.5 mass closure showed that secondary inorganic species were the dominant fractions of PM2.5 over the entire sampling (37.3%). 72-hour backward trajectory clusters indicated that most serious air pollution occurred when air masses transported from the Inner Mongolia, Shanxi and Zhengzhou. Health risk assessment revealed that noncancerous effects of heavy metals in PM2.5 of Xinxiang were unlikely happened, while lifetime cancer risks of heavy metals obviously exceeded the threshold, which might have a cancer risk for residents in Xinxiang. This study provided detailed composition data and first comprehensive analysis of PM2.5 during the Spring Festival period in Xinxiang.

Chemical characterization and source apportionment of size-resolved particles in Hong Kong sub-urban area

NASA Astrophysics Data System (ADS)

Gao, Yuan; Lee, Shun-Cheng; Huang, Yu; Chow, Judith C.; Watson, John G.

2016-03-01

Size-resolved particulate matter (PM) samples were collected with a 10-stage Micro-Orifice Uniform Deposit Impactor (MOUDI) at a sub-urban site (Tung Chung) in Hong Kong for four non-consecutive months representing four seasons from 2011 to 2012. Major chemical components were water-soluble anions (i.e., Cl-, NO3-, and SO42 -), cations (i.e., NH4+, Na+, K+, and Ca2 +), organic and elemental carbon and elements. Both chemical mass closure and positive matrix factorization (PMF) were employed to understand the chemical composition, resolve particle size modes, and evaluate the PM sources. Tri-modal size distributions were found for PM mass and major chemical components (e.g., SO42 -, NH4+, and OC). Mass median aerodynamic diameters (MMADs) with similar standard deviations (1.32 < σ < 1.42) were 0.4, 0.7 and 3.8 μm, consistent with condensation, droplet and coarse modes. A bi-modal distribution peaking at condensation and droplet modes was found for EC, with a single mode peaking at 3.8 μm for Cl-. Besides secondary SO42 -, carbonaceous aerosol dominated the condensation mode with 27% by engine exhaust and 18-19% each by residual oil combustion (shipping) and coal/biomass burning. Secondary SO42 - is also the most dominant component in the droplet mode, accounting for 23% of PM mass, followed by an industrial source (19%). Engine exhaust, secondary NO3-, and sea salt each accounted for 13-15% of PM mass. Sea salt and soil are the dominated sources in the coarse mode, accounting for 80% of coarse mass.

Chemical composition and source apportionment of PM10 and PM2.5 in different functional areas of Lanzhou, China.

PubMed

Qiu, Xionghui; Duan, Lei; Gao, Jian; Wang, Shulan; Chai, Fahe; Hu, Jun; Zhang, Jingqiao; Yun, Yaru

2016-02-01

To elucidate the air pollution characteristics of northern China, airborne PM10 (atmospheric dynamic equivalent diameter ≤ 10 μm) and PM2.5 (atmospheric dynamic equivalent diameter ≤ 2.5 μm) were sampled in three different functional areas (Yuzhong County, Xigu District and Chengguan District) of Lanzhou, and their chemical composition (elements, ions, carbonaceous species) was analyzed. The results demonstrated that the highest seasonal mean concentrations of PM10 (369.48 μg/m(3)) and PM2.5 (295.42 μg/m(3)) were detected in Xigu District in the winter, the lowest concentration of PM2.5 (53.15 μg/m(3)) was observed in Yuzhong District in the fall and PM10 (89.60 μg/m(3)) in Xigu District in the fall. The overall average OC/EC (organic carbon/elemental carbon) value was close to the representative OC/EC ratio for coal consumption, implying that the pollution of Lanzhou could be attributed to the burning of coal. The content of SNA (the sum of sulfate, nitrate, ammonium, SNA) in PM2.5 in Yuzhong County was generally lower than that at other sites in all seasons. The content of SNA in PM2.5 and PM10 in Yuzhong County was generally lower than that at other sites in all seasons (0.24-0.38), indicating that the conversion ratios from precursors to secondary aerosols in the low concentration area was slower than in the area with high and intense pollutants. Six primary particulate matter sources were chosen based on positive matrix factorization (PMF) analysis, and emissions from dust, secondary aerosols, and coal burning were identified to be the primary sources responsible for the particle pollution in Lanzhou. Copyright © 2015. Published by Elsevier B.V.

Size-segregated aerosol in a hot-spot pollution urban area: Chemical composition and three-way source apportionment.

PubMed

Bernardoni, V; Elser, M; Valli, G; Valentini, S; Bigi, A; Fermo, P; Piazzalunga, A; Vecchi, R

2017-12-01

In this work, a comprehensive characterisation and source apportionment of size-segregated aerosol collected using a multistage cascade impactor was performed. The samples were collected during wintertime in Milan (Italy), which is located in the Po Valley, one of the main pollution hot-spot areas in Europe. For every sampling, size-segregated mass concentration, elemental and ionic composition, and levoglucosan concentration were determined. Size-segregated data were inverted using the program MICRON to identify and quantify modal contributions of all the measured components. The detailed chemical characterisation allowed the application of a three-way (3-D) receptor model (implemented using Multilinear Engine) for size-segregated source apportionment and chemical profiles identification. It is noteworthy that - as far as we know - this is the first time that three-way source apportionment is attempted using data of aerosol collected by traditional cascade impactors. Seven factors were identified: wood burning, industry, resuspended dust, regional aerosol, construction works, traffic 1, and traffic 2. Further insights into size-segregated factor profiles suggested that the traffic 1 factor can be associated to diesel vehicles and traffic 2 to gasoline vehicles. The regional aerosol factor resulted to be the main contributor (nearly 50%) to the droplet mode (accumulation sub-mode with modal diameter in the range 0.5-1 μm), whereas the overall contribution from the two factors related to traffic was the most important one in the other size modes (34-41%). The results showed that applying a 3-D receptor model to size-segregated samples allows identifying factors of local and regional origin while receptor modelling on integrated PM fractions usually singles out factors characterised by primary (e.g. industry, traffic, soil dust) and secondary (e.g. ammonium sulphate and nitrate) origin. Furthermore, the results suggested that the information on size-segregated chemical composition in different size classes was exploited by the model to relate primary emissions to rapidly-formed secondary compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Radiocarbon determination of fossil and contemporary carbon contribution to aerosol in the Pacific Islands.

PubMed

Isley, C F; Nelson, P F; Taylor, M P; Williams, A A; Jacobsen, G E

2018-06-21

Combustion emissions are of growing concern across all Pacific Island Countries, which account for >10,000 km 2 of the earth's surface area; as for many other small island states globally. Apportioning emissions inputs for Suva, the largest Pacific Island city, will aid in development of emission reduction strategies. Total suspended particulate (TSP) and fine particulate (PM 2.5 ) samples were collected for Suva City, a residential area (Kinoya, TSP) and a mainly ocean-influenced site (Suva Point, TSP) from 2014 to 2015. Percentages of contemporary and fossil carbon were determined by radiocarbon analysis (accelerator mass spectrometry); for non‑carbonate carbon (NCC), elemental carbon (EC) and organic carbon (OC). Source contributions to particulate matter were identified and the accuracy of previous emissions inventory and source apportionment studies was evaluated. Suva Point NCC concentrations (2.7 ± 0.4 μg/m 3 ) were four times lower than for City (13 ± 2 μg/m 3 in TSP) and Kinoya (13 ± 1 μg/m 3 in TSP); demonstrating the contribution of land-based emissions activities in city and residential areas. In Suva City, total NCC in air was 81% (79%-83%) fossil carbon, from vehicles, shipping, power generation and industry; whilst in the residential area, 48% (46%-50%) of total NCC was contemporary carbon; reflecting the higher incidence of biomass and waste burning and of cooking activities. Secondary organic fossil carbon sources contributed >36% of NCC mass at the city and >29% at Kinoya; with biogenic carbon being Kinoya's most significant source (approx. 30% of NCC mass). These results support the previous source apportionment studies for the city area; yet show that, in line with emissions inventory studies, biomass combustion contributes more PM 2.5 mass in residential areas. Hence air quality management strategies need to target open burning activities as well as fossil fuel combustion. Copyright © 2018 Elsevier B.V. All rights reserved.

Source apportionment of PM₁₀ and PM₂.₅ in a desert region in northern Chile.

PubMed

Jorquera, Héctor; Barraza, Francisco

2013-02-01

Estimating contributions of anthropogenic sources to ambient particulate matter (PM) in desert regions is a challenging issue because wind erosion contributions are ubiquitous, significant and difficult to quantify by using source-oriented, dispersion models. A receptor modeling analysis has been applied to ambient PM(10) and PM(2.5) measured in an industrial zone ~20 km SE of Antofagasta (23.63°S, 70.39°W), a midsize coastal city in northern Chile; the monitoring site is within a desert region that extends from northern Chile to southern Perú. Integrated 24-hour ambient samples of PM(10) and PM(2.5) were taken with Harvard Impactors; samples were analyzed by X Ray Fluorescence, ionic chromatography (NO(3)(-) and SO(4)(=)), atomic absorption (Na(+), K(+)) and thermal optical transmission for elemental and organic carbon determination. Receptor modeling was carried out using Positive Matrix Factorization (US EPA Version 3.0); sources were identified by looking at specific tracers, tracer ratios, local winds and wind trajectories computed from NOAA's HYSPLIT model. For the PM(2.5) fraction, six contributions were found - cement plant, 33.7 ± 1.3%; soil dust, 22.4 ± 1.6%; sulfates, 17.8 ± 1.7%; mineral stockpiles and brine plant, 12.4 ± 1.2%; Antofagasta, 8.5 ± 1.3% and copper smelter, 5.3 ± 0.8%. For the PM(10) fraction five sources were identified - cement plant, 38.2 ± 1.5%; soil dust, 31.2 ± 2.3%; mineral stockpiles and brine plant, 12.7 ± 1.7%; copper smelter, 11.5 ± 1.6% and marine aerosol, 6.5 ± 2.4%. Therefore local sources contribute to ambient PM concentrations more than distant sources (Antofagasta, marine aerosol) do. Soil dust is enriched with deposition of marine aerosol and calcium, sulfates and heavy metals from surrounding industrial activities. The mean contribution of suspended soil dust to PM(10) is 50 μg/m(3) and the peak daily value is 104 μg/m(3). For the PM(2.5) fraction, suspended soil dust contributes with an average of 9.3 μg/m(3) and a peak daily value of 31.5 μg/m(3). Copyright © 2012 Elsevier B.V. All rights reserved.

Associations between air pollution and mortality in Phoenix, 1995-1997.

PubMed Central

Mar, T F; Norris, G A; Koenig, J Q; Larson, T V

2000-01-01

We evaluated the association between mortality outcomes in elderly individuals and particulate matter (PM) of varying aerodynamic diameters (in micrometers) [PM(10), PM(2.5), and PM(CF )(PM(10) minus PM(2.5))], and selected particulate and gaseous phase pollutants in Phoenix, Arizona, using 3 years of daily data (1995-1997). Although source apportionment and epidemiologic methods have been previously combined to investigate the effects of air pollution on mortality, this is the first study to use detailed PM composition data in a time-series analysis of mortality. Phoenix is in the arid Southwest and has approximately 1 million residents (9. 7% of the residents are > 65 years of age). PM data were obtained from the U.S. Environmental Protection Agency (EPA) National Exposure Research Laboratory Platform in central Phoenix. We obtained gaseous pollutant data, specifically carbon monoxide, nitrogen dioxide, ozone, and sulfur dioxide data, from the EPA Aerometric Information Retrieval System Database. We used Poisson regression analysis to evaluate the associations between air pollution and nonaccidental mortality and cardiovascular mortality. Total mortality was significantly associated with CO and NO(2) (p < 0.05) and weakly associated with SO(2), PM(10), and PM(CF) (p < 0. 10). Cardiovascular mortality was significantly associated with CO, NO(2), SO(2), PM(2.5), PM(10), PM(CF) (p < 0.05), and elemental carbon. Factor analysis revealed that both combustion-related pollutants and secondary aerosols (sulfates) were associated with cardiovascular mortality. PMID:10753094

The forecasting research of early warning systems for atmospheric pollutants: A case in Yangtze River Delta region

NASA Astrophysics Data System (ADS)

Song, Yiliao; Qin, Shanshan; Qu, Jiansheng; Liu, Feng

2015-10-01

The issue of air quality regarding PM pollution levels in China is a focus of public attention. To address that issue, to date, a series of studies is in progress, including PM monitoring programs, PM source apportionment, and the enactment of new ambient air quality index standards. However, related research concerning computer modeling for PM future trends estimation is rare, despite its significance to forecasting and early warning systems. Thereby, a study regarding deterministic and interval forecasts of PM is performed. In this study, data on hourly and 12 h-averaged air pollutants are applied to forecast PM concentrations within the Yangtze River Delta (YRD) region of China. The characteristics of PM emissions have been primarily examined and analyzed using different distribution functions. To improve the distribution fitting that is crucial for estimating PM levels, an artificial intelligence algorithm is incorporated to select the optimal parameters. Following that step, an ANF model is used to conduct deterministic forecasts of PM. With the identified distributions and deterministic forecasts, different levels of PM intervals are estimated. The results indicate that the lognormal or gamma distributions are highly representative of the recorded PM data with a goodness-of-fit R2 of approximately 0.998. Furthermore, the results of the evaluation metrics (MSE, MAPE and CP, AW) also show high accuracy within the deterministic and interval forecasts of PM, indicating that this method enables the informative and effective quantification of future PM trends.

Speciated Elemental and Isotopic Characterization of Atmospheric Aerosols - Recent Advances

NASA Astrophysics Data System (ADS)

Shafer, M.; Majestic, B.; Schauer, J.

2007-12-01

Detailed elemental, isotopic, and chemical speciation analysis of aerosol particulate matter (PM) can provide valuable information on PM sources, atmospheric processing, and climate forcing. Certain PM sources may best be resolved using trace metal signatures, and elemental and isotopic fingerprints can supplement and enhance molecular maker analysis of PM for source apportionment modeling. In the search for toxicologically relevant components of PM, health studies are increasingly demanding more comprehensive characterization schemes. It is also clear that total metal analysis is at best a poor surrogate for the bioavailable component, and analytical techniques that address the labile component or specific chemical species are needed. Recent sampling and analytical developments advanced by the project team have facilitated comprehensive characterization of even very small masses of atmospheric PM. Historically; this level of detail was rarely achieved due to limitations in analytical sensitivity and a lack of awareness concerning the potential for contamination. These advances have enabled the coupling of advanced chemical characterization to vital field sampling approaches that typically supply only very limited PM mass; e.g. (1) particle size-resolved sampling; (2) personal sampler collections; and (3) fine temporal scale sampling. The analytical tools that our research group is applying include: (1) sector field (high-resolution-HR) ICP-MS, (2) liquid waveguide long-path spectrophotometry (LWG-LPS), and (3) synchrotron x-ray absorption spectroscopy (sXAS). When coupled with an efficient and validated solubilization method, the HR-ICP-MS can provide quantitative elemental information on over 50 elements in microgram quantities of PM. The high mass resolution and enhanced signal-to-noise of HR-ICP-MS significantly advance data quality and quantity over that possible with traditional quadrupole ICP-MS. The LWG-LPS system enables an assessment of the soluble/labile components of PM, while simultaneously providing critical oxidation state speciation data. Importantly, the LWG- LPS can be deployed in a semi-real-time configuration to probe fine temporal scale variations in atmospheric processing or sources of PM. The sXAS is providing complementary oxidation state speciation of bulk PM. Using examples from our research; we will illustrate the capabilities and applications of these new methods.

Integrated Forensics Approach to Fingerprint PCB Sources in Sediments using Rapid Sediment Characterization (RSC) and Advanced Chemical Fingerprinting (ACF)

DTIC Science & Technology

2012-06-01

Source Compositions for HPS Dataset ...........................................78 Figure 25 Comparison of Source Apportionment for HPS Dataset...The similarity in the three source patterns from HPS makes the apportionment less certain at that site compared to the four source patterns at... apportionment of these sources across the site. Overall these techniques passed all the performance assessment tests that are presented in Section 6. 3.3

Construction of Fine Particles Source Spectrum Bank in Typical Region and Empirical Research of Matching Diagnosis

NASA Astrophysics Data System (ADS)

Wang, Xing; Sun, Wenliang; Guo, Min; Li, Minjiao; Li, Wan

2018-01-01

The research object of this paper is fine particles in typical region. The construction of component spectrum bank is based on the technology of online source apportionment, then the result of the apportionment is utilized to verify the effectiveness of fine particles component spectrum bank and which also act as the matching basis of online source apportionment receptor sample. On the next, the particle source of air pollution is carried through the matching diagnosis empirical research by utilizing online source apportionment technology, to provide technical support for the cause analysis and treatment of heavy pollution weather.

Seasonal variability in chemical composition and source apportionment of sub-micron aerosol over a high altitude site in Western Ghats, India

NASA Astrophysics Data System (ADS)

Mukherjee, Subrata; Singla, Vyoma; Pandithurai, Govindan; Safai, P. D.; Meena, G. S.; Dani, K. K.; Anil Kumar, V.

2018-05-01

This manuscript reports the seasonal variation of chemically speciated sub-micron aerosol particles (diameter < 1 μm). An Aerosol Chemical Speciation Monitor (ACSM) was used to measure the mass concentration of non-refractory particulate matter (NR-PM1) at a high-altitude site in the Western Ghats, India from March 2016 to February 2017. The mass concentration of NR-PM1 averaged at 7.5 ± 6.5 μgm-3, with major contributions from organics (59%) and sulfates (23%). Positive matrix factorization (PMF) was applied on the measured mass spectra of organic aerosol (OA) to derive the sources distinctive of each season (Summer, Monsoon, Post-Monsoon and Winter). The four OA factors (two primary OA and two oxygenated OA) resolved during summer, post-monsoon and winter season. However, only one oxygenated factor resolved during monsoon and contributed only 20% to the total OA. The factors associated with primary emissions dominated during the monsoon, whereas factors related to secondary formation dominated in other three seasons. During summer, an isoprene derived SOA - IEPOX-OA (isoprene-epoxydiol OA) contributed ∼17% to the total OA. Cluster and concentration weighted trajectory (CWT) analyses were performed to identify the possible source regions of NR-PM1 mass concentration observed at the receptor site. The analysis identifies Central India as the potential source region of transported aerosol during post-monsoon and winter season. Our study suggests that contributions from both local sources and regional transport are important in governing mass concentration of PM1 over Mahabaleshwar.

Long-term trends of ambient particulate matter emission source contributions and the accountability of control strategies in Hong Kong over 1998-2008

NASA Astrophysics Data System (ADS)

Yuan, Zibing; Yadav, Varun; Turner, Jay R.; Louie, Peter K. K.; Lau, Alexis Kai Hon

2013-09-01

Despite extensive emission control measures targeting motor vehicles and to a lesser extent other sources, annual-average PM10 mass concentrations in Hong Kong have remained relatively constant for the past several years and for some air quality metrics, such as the frequency of poor visibility days, conditions have degraded. The underlying drivers for these long-term trends were examined by performing source apportionment on eleven years (1998-2008) of data for seven monitoring sites in the Hong Kong PM10 chemical speciation network. Nine factors were resolved using Positive Matrix Factorization. These factors were assigned to emission source categories that were classified as local (operationally defined as within the Hong Kong Special Administrative Region) or non-local based on temporal and spatial patterns in the source contribution estimates. This data-driven analysis provides strong evidence that local controls on motor vehicle emissions have been effective in reducing motor vehicle-related ambient PM10 burdens with annual-average contributions at neighborhood- and larger-scale monitoring stations decreasing by ˜6 μg m-3 over the eleven year period. However, this improvement has been offset by an increase in annual-average contributions from non-local contributions, especially secondary sulfate and nitrate, of ˜8 μg m-3 over the same time period. As a result, non-local source contributions to urban-scale PM10 have increased from 58% in 1998 to 70% in 2008. Most of the motor vehicle-related decrease and non-local source driven increase occurred over the period 1998-2004 with more modest changes thereafter. Non-local contributions increased most dramatically for secondary sulfate and secondary nitrate factors and thus combustion-related control strategies, including but not limited to power plants, are needed for sources located in the Pearl River Delta and more distant regions to improve air quality conditions in Hong Kong. PMF-resolved source contribution estimates were also used to examine differential contributions of emission source categories during high PM episodes compared to study-average behavior. While contributions from all source categories increased to some extent on high PM days, the increases were disproportionately high for the non-local sources. Thus, controls on emission sources located outside the Hong Kong Special Administrative Region will be needed to effectively decrease the frequency and severity of high PM episodes.

Semi-continuous mass closure of the major components of fine particulate matter in Riverside, CA

NASA Astrophysics Data System (ADS)

Grover, Brett D.; Eatough, Norman L.; Woolwine, Woods R.; Cannon, Justin P.; Eatough, Delbert J.; Long, Russell W.

The application of newly developed semi-continuous aerosol monitors allows for the measurement of all the major species of PM 2.5 on a 1-h time basis. Temporal resolution of both non-volatile and semi-volatile species is possible. A suite of instruments to measure the major chemical species of PM 2.5 allows for semi-continuous mass closure. A newly developed dual-oven Sunset carbon monitor is used to measure non-volatile organic carbon, semi-volatile organic carbon and elemental carbon. Inorganic species, including sulfate and nitrate, can be measured with an ion chromatograph based sampler. Comparison of the sum of the major chemical species in an urban aerosol with mass measured by an FDMS resulted in excellent agreement. Linear regression analysis resulted in a zero-intercept slope of 0.98±0.01 with an R2=0.86. One-hour temporal resolution of the major species of PM 2.5 may reduce the uncertainty in receptor based source apportionment modeling, will allow for better forecasting of PM 2.5 episodes, and may lead to increased understanding of related health effects.

Source apportionment of the carcinogenic potential of polycyclic aromatic hydrocarbons (PAH) associated to airborne PM10 by a PMF model.

PubMed

Callén, M S; Iturmendi, A; López, J M; Mastral, A M

2014-02-01

In order to perform a study of the carcinogenic potential of polycyclic aromatic hydrocarbons (PAH), benzo(a)pyrene equivalent (BaP-eq) concentration was calculated and modelled by a receptor model based on positive matrix factorization (PMF). Nineteen PAH associated to airborne PM10 of Zaragoza, Spain, were quantified during the sampling period 2001-2009 and used as potential variables by the PMF model. Afterwards, multiple linear regression analysis was used to quantify the potential sources of BaP-eq. Five sources were obtained as the optimal solution and vehicular emission was identified as the main carcinogenic source (35 %) followed by heavy-duty vehicles (28 %), light-oil combustion (18 %), natural gas (10 %) and coal combustion (9 %). Two of the most prevailing directions contributing to this carcinogenic character were the NE and N directions associated with a highway, industrial parks and a paper factory. The lifetime lung cancer risk exceeded the unit risk of 8.7 x 10(-5) per ng/m(3) BaP in both winter and autumn seasons and the most contributing source was the vehicular emission factor becoming an important issue in control strategies.

Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): Emissions of particulate matter from wood and dung cooking fires, brick kilns, generators, trash and crop residue burning

NASA Astrophysics Data System (ADS)

Stone, Elizabeth; Jayarathne, Thilina; Stockwell, Chelsea; Christian, Ted; Bhave, Prakash; Siva Praveen, Puppala; Panday, Arnico; Adhikari, Sagar; Maharjan, Rashmi; Goetz, Doug; DeCarlo, Peter; Saikawa, Eri; Yokelson, Robert

2016-04-01

The Nepal Ambient Monitoring and Source Testing Experiment (NAMASTE) field campaign targeted the in situ characterization of widespread and under-sampled combustion sources. In Kathmandu and the Terai, southern Nepal's flat plains, samples of fine particulate matter (PM2.5) were collected from wood and dung cooking fires (n = 22), generators (n = 2), groundwater pumps (n = 2), clamp kilns (n = 3), zig-zag kilns (n = 3), trash burning (n = 4), one heating fire, and one crop residue fire. Co-located measurements of carbon dioxide, carbon monoxide, and volatile organic compounds allowed for the application of the carbon mass balance approach to estimate emission factors for PM2.5, elemental carbon, organic carbon, and water-soluble inorganic ions. Organic matter was chemically speciated using gas chromatography - mass spectrometry for polycyclic aromatic hydrocarbons, sterols, n-alkanes, hopanes, steranes, and levoglucosan, which accounted for 2-8% of the measured organic carbon. These data were used to develop molecular-marker based profiles for use in source apportionment modeling. This study provides quantitative emission factors for particulate matter and its constituents for many important combustion sources in Nepal and South Asia.

Impacts of updated emission inventories on source apportionment of fine particle and ozone over the southeastern U.S.

NASA Astrophysics Data System (ADS)

Zhang, Yang; Wang, Wei; Wu, Shiang-Yuh; Wang, Kai; Minoura, Hiroaki; Wang, Zifa

2014-05-01

As the U.S. Environmental Protection Agency updates the National Emission Inventory (NEI), the source contributions (SC) of major source sectors to major pollutants based on source apportionment techniques should be periodically reassessed to reflect changes in SCs due to changes in emissions. This work assesses emission updates from the 1999 NEI version 2 (NEI99v2) and the 2005 NEI (NEI05) and the resulting differences in SCs using the two inventories. Large differences exist in the emissions of nitrogen oxide, formaldehyde, ammonia, terpene, and primary PM2.5 between NEI99v2 and NEI05. Differences in emissions lead to differences in model performance and source appointment. SCs of ten major source categories to fine particulate matter (PM2.5) are estimated using the Community Multiscale Air Quality modeling system with the Brute Force Method (CMAQ/BFM) andNEI05and compared with those obtained previously using CMAQ/BFM with NEI99v2. In January, compared to CMAQ/BFM (NEI99v2), CMAQ/BFM (NEI05) shows that miscellaneous areas, biomass burning, and coal combustion remain the top three contributors to PM2.5 but with different ranking and higher SCs (17.7%, 16.0%, and 14.1% for NEI05 vs. 11.8%, 13.7%, and 10.8% for NEI99v2, respectively). In July, coal combustion, miscellaneous areas, and industrial processes remain the top three with higher SCs (41.9%, 14.1%, and 8.8% for NEI05 vs.30.8%, 8.9%, and 6.9% for NEI99v2, respectively). Those changes in SCs are attributed to increased primary PM2.5 (PPM) emissions in NEI05 and increases in relative contributions of miscellaneous areas and coal combustion to the emissions of PPM, NH3, and SO2.SCs from diesel and gasoline vehicles decrease in both months, due to decreased contributions of gasoline vehicles to SO2 and NH3 emissions and those of diesel vehicles to NOx and PPM emissions. Compared with CMAQ/BFM (NEI99v2), SCs from other combustion and biomass burning are higher in Florida, due to substantial increases in formaldehyde and PPM emissions in NEI05, resulting from higher wildfire emissions and state emission updates. SCs from industrial processes increase and those from diesel and gasoline vehicles decrease in urban areas. SCs of O3 from most sources in both months increase due to a large increase in their contributions to NOx emissions, except for diesel vehicles in July, which decreases over domainwide due to a relative decrease in NOx emissions. These results provide valuable information for policy makers to formulate and adjust emission control strategies as the NEI is continuously updated.

Source characterization of ambient fine aerosol in Singapore during a haze episode in 2015

NASA Astrophysics Data System (ADS)

Hapsari Budisulistiorini, Sri; Riva, Matthieu; Williams, Michael; Miyakawa, Takuma; Komazaki, Yuichi; Chen, Jing; Surratt, Jason; Kuwata, Mikinori

2017-04-01

Recurring transboundary haze from Indonesia peatland fires in the previous decades has significantly elevated particulate matter (PM) concentration in Southeast Asia, particularly during the 2015 El Niño event. Previous studies have investigated chemical composition of particles emitted during haze episodes; however, they were limited to time-integrated samples and the number of identified compounds. Low time-resolution measurement results in co-variance of PM sources; therefore, higher time-resolution measurement is important in PM source apportionment. Between October 10-31, 2015, Aerodyne Time-of-Flight Aerosol Chemical Speciation Monitor (ToF-ACSM) was deployed for real-time chemical characterization of ambient submicron PM (NR-PM1) in Singapore. Simultaneously, PM2.5 filter samples were collected for molecular-level organic aerosol (OA) constituents, organic carbon (OC), elemental carbon (EC) and water-soluble OC (WSOC) analyses. OA constituents were quantified by gas chromatography interfaced to electron ionization mass spectrometry (GC/EI-MS) and ultra-performance liquid chromatography interfaced to electrospray ionization high-resolution quadrupole time-of-flight mass spectrometer operated in the negative ion mode (UPLC/(-)ESI-HR-Q-TOFMS). OA and SO42- are dominant components of the haze particles, accounting for ˜77% and ˜12% of the total NR-PM1 mass, respectively. OC/EC ratio of 4.8 might indicate formation of secondary OA (SOA) and aerosols from biomass burning, including those from peat burning. OA fraction from ToF-ACSM measurements was analyzed for source apportionment using a bilinear model through multi-linear engine algorithm (ME-2) in graphical user interface SoFi (Source Finder). Five OA factors were identified: hydrocarbon-like OA (HOA), biomass burning OA (BBOA), peat burning OA (PBOA), low-volatility oxygenated OA (LV-OOA), and semi-volatile oxygenated OA (SV-OOA). The HOA factor shows a distinct diurnal profile peaking in the morning and evening, suggesting traffic influences. The BBOA factor was identified based on factor profile of wood burning particles and correlated with known biomass burning tracers (i.e. levoglucosan and mannosan). The PBOA factor was identified based on factor profile of laboratory-generated peat burning particles. This factor would be further identified with OA constituents in peat burning particles, such as brown carbon constituents. The LV-OOA and SV-OOA factors peak in the afternoon indicating they were likely formed through photochemistry. The LV-OOA factor might be a product of biomass burning aerosol aging as indicated by temporal trend correlations with BBOA and PBOA factors (r2 = 0.7-0.8). Contributions of the HOA and SV-OOA factors to OA mass are ˜12% and ˜21%, respectively. The biomass burning-related factors (BBOA and PBOA) account for ˜29% of OA mass, which likely indicates a lower-bound estimate of the transboundary impacts of primary emissions from peatland fires. The transboundary impacts of secondary aerosol from peatland fires might be represented by the LV-OOA factor accounting for ˜37% of OA mass. Overall, the transboundary haze could contribute to ˜66% of OA concentration, suggesting the strong influence of Indonesia peatland fires on the air quality of Singapore.

The recent and future health burden of air pollution apportioned across U.S. sectors.

PubMed

Fann, Neal; Fulcher, Charles M; Baker, Kirk

2013-04-16

Recent risk assessments have characterized the overall burden of recent PM2.5 and ozone levels on public health, but generally not the variability of these impacts over time or by sector. Using photochemical source apportionment modeling and a health impact function, we attribute PM2.5 and ozone air quality levels, population exposure and health burden to 23 industrial point, area, mobile and international emission sectors in the Continental U.S. in 2005 and 2016. Our modeled policy scenarios account for a suite of emission control requirements affecting many of these sectors. Between these two years, the number of PM2.5 and ozone-related deaths attributable to power plants and mobile sources falls from about 68,000 (90% confidence interval from 48,000 to 87,000) to about 36,000 (90% confidence intervals from 26,000 to 47,000). Area source mortality risk grows slightly between 2005 and 2016, due largely to population growth. Uncertainties relating to the timing and magnitude of the emission reductions may affect the size of these estimates. The detailed sector-level estimates of the size and distribution of mortality and morbidity risk suggest that the air pollution mortality burden has fallen over time but that many sectors continue to pose a substantial risk to human health.

Evolution of Submicrometer Organic Aerosols during a Complete Residential Coal Combustion Process.

PubMed

Zhou, Wei; Jiang, Jingkun; Duan, Lei; Hao, Jiming

2016-07-19

In the absence of particulate matter (PM) control devices, residential coal combustion contributes significantly to ambient PM pollution. Characterizing PM emissions from residential coal combustion with high time resolution is beneficial for developing control policies and evaluating the environmental impact of PM. This study reports the evolution of submicrometer organic aerosols (OA) during a complete residential coal combustion process, that is, from fire start to fire extinction. Three commonly used coal types (bituminous, anthracite, and semicoke coals) were evaluated in a typical residential stove in China. For all three types of coal, the OA emission exhibited distinct characteristics in the four stages, that is, ignition, fierce combustion, relatively stable combustion, and ember combustion. OA emissions during the ignition stage accounted for 58.2-85.4% of the total OA emission of a complete combustion process. The OA concentration decreased rapidly during the fierce combustion stage and remained low during the relatively stable combustion stage. During these two stages, a significant ion peak of m/z 73 from organic acids were observed. The degree of oxidation of the OA increased from the first stage to the last stage. Implications for ambient OA source-apportionment and residential PM emission characterization and control are discussed.

Source and chemical species characterization of PM10 and human health risk assessment of semi-urban, urban and industrial areas of West Bengal, India.

PubMed

Ghosh, Suraj; Rabha, Rumi; Chowdhury, Mallika; Padhy, Pratap Kumar

2018-09-01

Levels of particulate matter of size ten micron (PM 10 ) in outdoor air, potential PM 10 -bound seven metals - manganese, zinc, cadmium, lead, copper, nickel and cobalt - and twelve water-soluble organic and inorganic ionic components - fluoride, acetate, chloride, nitrite, bromide, nitrate, phosphate, sulfate, oxalate, sodium, potassium and calcium - were investigated during two different season. Atmospheric PM 10 samples were collected concurrently from three different sites, i.e., Durgapur (Industrial), Berhampore (Urban) and Bolpur (Semi-urban), West Bengal, India, during summer (April-June 2014) and winter (December 2014-February 2015). Average PM 10 levels were found to be in the range of 189.58-219.96 μg/m 3 at the semi-urban site, 293.41-324.27 μg/m 3 at the urban site and 316.93-344.69 μg/m 3 at the industrial site during summer and winter season respectively. Data on metals and water soluble ions were analyzed statistically (Principal Component Analysis and Factor Analysis) for their source identification and apportionment in the study areas. Principle component analysis models, from three different sites, identified four different factors which share common sources, viz., soil & road re-suspension, motor vehicle and traffic, waste dumping, biomass aerosols, and construction. The pollution load and health risk assessments of selected metals were undertaken in three different sites, within children and adults of the study areas, and were found to be within the safe range. Furthermore, an attempt has also been made to provide basic information on pollution, their sources and exposure pathways for humans in the vicinity of semi-urban, urban and industrial regions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Source apportionment revisited for long-term measurements of fine aerosol trace elements at two locations in southern Norway

NASA Astrophysics Data System (ADS)

Maenhaut, Willy

2018-02-01

Five-year-long (1991-1996) aerosol trace element data sets for the fine (PM2) size fraction from the sites of Birkenes and Skreådalen in southern Norway were reanalysed by US EPA positive matrix factorization PMF5 in order to assess the sources and their contribution to the PM2 aerosol. The data sets contained the concentrations of the particulate mass (PM), black carbon (BC) and 21 elements in over 700 samples for each of the two sites. The PM was obtained from weighing with a microbalance and BC was determined with a light reflectance technique. The data for the elements were obtained by a combination of particle-induced X-ray emission and instrumental neutron activation analysis. Eight source factors were retained for each site, i.e., (i) secondary sulfate, which accounted for around 40% of the average measured PM2 mass, (ii) wood burning, with BC, K, Zn and As, which accounted for about 17%, (iii) an iodine factor (with also Br and Se), which is probably related to a marine biogenic source and was responsible for about 6.5%, (iv) aged sea salt with Na, Mg, Cl and Ca, but heavily depleted in Cl; (v) a crustal factor containing Al, Si, Ca, Ti and Fe; (vi) a heavy oil burning factor with V and Ni in a ratio of 3-4; (vii) a general pollution factor (with Cu, Zn, As, Se, Sb and Pb), and (viii) an almost pure manganese factor, which is attributed to Mn and FeMn industries in southern Norway. The results were substantially different from those of an earlier PMF analysis, in which use was made of PMF2.

Nested Source Apportionment of Secondary Inorganic Aerosol over Yangtze River Delta during Heavy Haze Episodes

NASA Astrophysics Data System (ADS)

Luo, L.; Cheng, Z.

2017-12-01

Secondary inorganic aerosols (SNA), i.e., sulfate, nitrate and ammonium, account for over 50% of fine particulate matter (PM2.5) during heavy haze episodes over Yangtze River Delta (YRD) region of China. Understanding the origin and transport of SNA is crucial for alleviating haze pollution over YRD. The long range transport from outer-YRD regions had significant influence on SNA during haze episodes over YRD, especially in winter. However, previous studies only using single domain for source analysis are limited on quantifying the local and transported sources in province scale altogether. In this study, the Integrated Source Apportionment Method (ISAM) based on the Weather Research and Forecasting and Community Multi-scale Air Quality (WRF-CMAQ) models was performed to two nested domains, one covering east of China and the other embracing YRD, for source apportionment of SNA in YRD during January, 2015. The results indicated that the outer-YRD transport mainly from upwind northwestern provinces, Shandong and Henan, was the dominant contributor accounting for 36.2% of sulfate during pollution episodes. For nitrate, inner-YRD and outer-YRD transport were the two evenly major regional sources, contributing 51.9% of nitrate during hazes. However, local accumulation was the first contributor accounting for 73.9% of ammonium. The long lifetime of formation process for sulfate and nitrate caused the conspicuous transport effect driven by wind when adjacent regions under severe pollution. Although the total effects of long and short distant transport played a major role for the level of sulfate and nitrate, the extent of contribution from local accumulation was similar with them even larger in province scale. Industry followed by power plant were two principal sources of sulfate for all three types of regional contribution. The main sectoral sources of nitrate were industry and transport for local accumulation while power plant besides them for inner-YRD and outer-YRD transport. For ammonium, volatile sources were major origin for local accumulation while agriculture for inner-YRD transport. These results demonstrate the importance for outer-YRD control during haze episodes for sulfate and nitrate while local emission control for ammonium in YRD.

Source identification and seasonal variation of polycyclic aromatic hydrocarbons associated with atmospheric fine and coarse particles in the Metropolitan Area of Porto Alegre, RS, Brazil

NASA Astrophysics Data System (ADS)

Teixeira, Elba Calesso; Agudelo-Castañeda, Dayana M.; Fachel, Jandyra Maria Guimarães; Leal, Karen Alam; Garcia, Karine de Oliveira; Wiegand, Flavio

2012-11-01

The purpose of the present study was to evaluate the polycyclic aromatic hydrocarbons (PAHs) in fine (PM2.5) and coarse particles (PM2.5-10) in an urban and industrial area in the Metropolitan Area of Porto Alegre (MAPA), Brazil. Sixteen U.S. Environmental Protection Agency (EPA) priority polycyclic aromatic hydrocarbons (PAHs) were measured. Filters containing ambient air particulate were extracted with dichloromethane using Soxhlet. Extracts were later analyzed, for determining PAH concentrations, using a gaseous chromatograph coupled with a mass spectrometer (GC-MS). The polycyclic aromatic hydrocarbons (PAHs) were more concentrated in PM2.5 with an average of 70% of total PAHs in the MAPA. The target PAH apportionment among the main emission sources was carried out by diagnostic PAH concentration ratios, and principal component analysis (PCA). PAHs with higher molecular weight showed higher percentages in the fine particles in the MAPA. Based on the diagnostic ratios and PCA analysis, it may be concluded that the major contribution of PAHs was from vehicular sources (diesel and gasoline), especially in the PM2.5 fraction, as well as coal and wood burning. The winter/summer ratio in the PM2.5 and PM2.5-10 fractions in the MAPA was 3.1 and 1.8, respectively, revealing the seasonal variation of PAHs in the two fractions. The estimated toxicity equivalent factor (TEF), used to assess the contribution of the carcinogenic potency, confirms a significant presence of the moderately active carcinogenic PAHs BaP and DahA in the samples collected in the MAPA.

Numerical study on seasonal variations of gaseous pollutants and particulate matters in Hong Kong/Pearl River Delta Region

NASA Astrophysics Data System (ADS)

Kwok, Roger Hiu Fung

Air pollution in Hong Kong (HK) causes problems in visibility and public health, which are worsening over past few years. Out of particulate matters (PM) inhalable into respiratory system, 30% is contributed by sulfate (SO4), 40% by organic carbon (OC), and 10% by elemental carbon (EC). A meso-scale numerical modeling system CMAQ is devised to simulate the air quality in January (winter), April (spring), July (summer) and October (autumn) 2004, driven by meteorology simulated by MM5 and emission sources in China including Hong Kong. Observational and measurement data from Hong Kong Environmental Protection Department Air Quality network are compared with the model results. With respect to pollutant concentration level, model-observation agreement is reasonably well, especially in PM species sulfate, organic carbon (OC) and elemental carbon (EC); and gaseous species SO2, NOx and ozone. In terms of PM composition, the model agrees with the measurement in fractions of sulfate, OC and EC. Higher PM level in autumn and winter is associated with northeasterly winds due to continental outflow. To further investigate emission sources contributing to HK, a source apportioning method called Tagged Species Source Apportionment (TSSA) algorithm is applied to study contributions to level of SO4, SO2 and EC in HK. It is found that while sources beyond PRD are observed in entire HK during January and October 2004, emitting sectors are different among western HK, downtown area, and the east countryside. Specifically, power plants and vehicles from HK and Shenzhen affect the western new towns, while power plants, vehicles and ships within HK determine the downtown pollutants' level. The countryside is mainly influenced by sources beyond PRD.

High concentrations of heavy metals in PM from ceramic factories of Southern Spain

NASA Astrophysics Data System (ADS)

Sánchez de la Campa, Ana M.; de la Rosa, Jesús D.; González-Castanedo, Yolanda; Fernández-Camacho, Rocío; Alastuey, Andrés; Querol, Xavier; Pio, Casimiro

2010-06-01

In this study, physicochemical characterization of Atmospheric Particulate Matter (PM) was performed in an urban-industrial site background (Bailén, Southern Spain), highly influenced by the impact of emission plumes from ceramic factories. This area is considered one of the towns with the highest PM 10 levels and average SO 2 concentration in Spain. A three stages methodology was used: 1) real-time measurements of levels of PM 10 and gaseous pollutants, and sampling of PM; 2) chemical characterization using ICP-MS, ICP-OES, CI and TOT, and source apportionment analysis (receptor modelling) of PM; and 3) chemical characterization of emission plumes derived from representative factories. High ambient air concentrations were found for most major components and trace elements compared with other industrialized towns in Spain. V and Ni are considered fingerprints of PM derived from the emissions of brick factories in this area, and were shown to be of particular interest. This highlights the high V and Ni concentrations in PM 10 (122 ngV/m 3 and 23.4 ngNi/m 3), with Ni exceeding the 2013 annual target value for the European Directive 2004/107/EC (20 ng/m 3). The methodology of this work can be used by Government departments responsible for Environment and Epidemiology in planning control strategies for improving air quality.

An inter-comparison of PM2.5 at urban and urban background sites: Chemical characterization and source apportionment

NASA Astrophysics Data System (ADS)

Cesari, D.; Donateo, A.; Conte, M.; Merico, E.; Giangreco, A.; Giangreco, F.; Contini, D.

2016-06-01

A measurement campaign was performed between 04/03/2013 and 17/07/2013 for simultaneous collection of PM2.5 samples in two nearby sites in southeastern Italy: an urban site and an urban background site. PM2.5 at the two sites were similar; however, the chemical composition and the contributions of the main sources were significantly different. The coefficients of divergence (CODs) showed spatial heterogeneity of EC (higher at the urban site because of traffic emissions) and of all metals. Major ions (NH4+, Na+, and SO42 -) and OC had low CODs, suggesting a homogeneous distribution of sea spray, secondary sulfate, and secondary organic matter (SOM = 1.6*OCsec, where OCsec is the secondary OC). The strong correlations between Na+ and Cl-, and the low Cl-/Na+ ratios, suggested the presence of aged sea spray with chloride depletion (about 79% of Cl-) and formation of sodium nitrate at both sites. In both sites, the non-sea-salt sulfate was about 97% of sulfate, and the strong correlation between SO42 - and NH4+ indicated that ammonium was present as ammonium sulfate. However, during advection of Saharan Dust, calcium sulfate was present rather than ammonium sulfate. The source apportionment was performed using the Positive Matrix Factorization comparing outputs of model EPA PMF 3.0 and 5.0 version. Six aerosol sources were identified at both sites: traffic, biomass burning, crustal-resuspended dust, secondary nitrate, marine aerosol, and secondary sulfate. The PMF3.0 model was not completely able, in these sites, to separate marine contribution from secondary nitrate and secondary sulfate from OC, underestimating the marine contribution and overestimating the secondary sulfate with respect to stoichiometric calculations. The application of specific constraints on PMF5.0 provided cleaner profiles, improving the comparison with stoichiometric calculations. The seasonal trends revealed larger biomass burning contributions during the cold period at both sites due to domestic heating emissions added to those of agricultural practices. Secondary aerosol represented about 50% of PM2.5 at both sites (about 1/3 due to SOM), with a slight increase during the cold season, probably due to the formation of secondary OC via gas-to-particle conversion. Secondary inorganic aerosol (nitrate plus sulfate) did not show seasonal trend because the reduction of nitrate due to thermal instability during the warm season was compensated by an almost equivalent increase of sulfate.

Selective Collection of Airborne Particulate Matter

DOE PAGES

Cheng, Meng -Dawn

2018-01-01

Here, airborne particulate matter (PM) or aerosol particles or simply aerosol are ubiquitous in the environment. They originate from natural processes such as wind erosion, road dust, forest fire, ocean spray and volcanic eruption, and man-made sources consuming fossil fuels resulting from utility power generation and transportation, and numerous industrial processes. Aerosols affect our daily life in many ways; PM reduces visibility in many polluted metropolitan areas, adversely impact human health and local air quality around the world. Aerosol alters cloud cycles and change atmospheric radiation balance. Changes in daily mortality associated with particulate air pollution were typically estimated atmore » approximately 0.5–1.5% per 10 µg m –3 increase in PM10 concentrations. Laden et al. (2006) found “an increase in overall mortality associated with each 10 µg m –3 increase in PM2.5 concentration either as the overall mean (rate ratio [RR], 1.16; 95% confidence interval [CI], 1.07–1.26) or as exposure in the year of death (RR, 1.14; 95% CI, 1.06–1.22). PM2.5 exposure was associated with lung cancer (RR, 1.27; 95% CI, 0.96–1.69) and cardiovascular deaths (RR, 1.28; 95% CI, 1.13–1.44). Improved overall mortality was associated with decreased mean PM 2.5 (10 µg m –3) between periods (RR, 0.73; 95% CI, 0.57–0.95)”. Aerosol particles also play an important role in source identification and apportionment. Since the PM problem is associated with many facets of societal issues such as energy production and economic development, making progress on reducing the effects of PM will require integrated strategies that bring together scientists, engineers and decision makers from different disciplines to consider tradeoffs.« less

Wintertime aerosol chemical composition and source apportionment of the organic fraction across Ireland

NASA Astrophysics Data System (ADS)

Ovadnevaite, J.; Lin, C.; Ceburnis, D.; Huang, R. J. J.; O'Dowd, C. D. D.

2017-12-01

A national wide characterization of PM1 was studied for the first time using a high-time resolution Aerosol Chemical Speciation Monitor (ACSM) and Aethalometer in Ireland during the heating season. Dublin, the capital of Ireland, is the most polluted area with an average PM1 of 7.6 μg/m3, with frequent occurrence of peak concentration over 200 μg/m3 primarily due to solid fuels burning, while Mace Head, in the west coast, is least polluted with an average PM1 of 0.8 μg/m3 due to the distance from the emission sources. The organic aerosol is the most dominant species across Ireland, contributing 65%, 58%, 32%, 33% to total PM1 mass in Dublin, Birr, Carnsore Point, and Mace Head, respectively. Birr, a small town in the midland of Ireland, has comparable PM1 levels (4.8 μg/m3) and similar chemical compositions with that in Dublin. Carnsore Point, on the southeast coast, has similar composition with that at Mace Head, but nearly 3 times the levels of PM1 mass due to its relative closeness to other European countries. Positive matrix factorization (PMF) with the multi-linear engine (ME-2) was performed on the organic matrix to quantify the contribution of factor candidates. Peat burning was found to be the dominant factor across Ireland, contributing more than 40% of the total organic mass in Dublin and Birr while OOA is dominant at rural Carnsore Point and Mace Head. Possible geographic origins of PM1 species and organic factors using polar plots were explored. The findings of solid fuels burning (primarily peat burning) driving the pollution episodes suggest an elimination or controlled emission of solid fuels burning would reduce PM1 by at least 50%.

Selective Collection of Airborne Particulate Matter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Meng -Dawn

Here, airborne particulate matter (PM) or aerosol particles or simply aerosol are ubiquitous in the environment. They originate from natural processes such as wind erosion, road dust, forest fire, ocean spray and volcanic eruption, and man-made sources consuming fossil fuels resulting from utility power generation and transportation, and numerous industrial processes. Aerosols affect our daily life in many ways; PM reduces visibility in many polluted metropolitan areas, adversely impact human health and local air quality around the world. Aerosol alters cloud cycles and change atmospheric radiation balance. Changes in daily mortality associated with particulate air pollution were typically estimated atmore » approximately 0.5–1.5% per 10 µg m –3 increase in PM10 concentrations. Laden et al. (2006) found “an increase in overall mortality associated with each 10 µg m –3 increase in PM2.5 concentration either as the overall mean (rate ratio [RR], 1.16; 95% confidence interval [CI], 1.07–1.26) or as exposure in the year of death (RR, 1.14; 95% CI, 1.06–1.22). PM2.5 exposure was associated with lung cancer (RR, 1.27; 95% CI, 0.96–1.69) and cardiovascular deaths (RR, 1.28; 95% CI, 1.13–1.44). Improved overall mortality was associated with decreased mean PM 2.5 (10 µg m –3) between periods (RR, 0.73; 95% CI, 0.57–0.95)”. Aerosol particles also play an important role in source identification and apportionment. Since the PM problem is associated with many facets of societal issues such as energy production and economic development, making progress on reducing the effects of PM will require integrated strategies that bring together scientists, engineers and decision makers from different disciplines to consider tradeoffs.« less

Source apportionment and sensitivity analysis: two methodologies with two different purposes

NASA Astrophysics Data System (ADS)

Clappier, Alain; Belis, Claudio A.; Pernigotti, Denise; Thunis, Philippe

2017-11-01

This work reviews the existing methodologies for source apportionment and sensitivity analysis to identify key differences and stress their implicit limitations. The emphasis is laid on the differences between source impacts (sensitivity analysis) and contributions (source apportionment) obtained by using four different methodologies: brute-force top-down, brute-force bottom-up, tagged species and decoupled direct method (DDM). A simple theoretical example to compare these approaches is used highlighting differences and potential implications for policy. When the relationships between concentration and emissions are linear, impacts and contributions are equivalent concepts. In this case, source apportionment and sensitivity analysis may be used indifferently for both air quality planning purposes and quantifying source contributions. However, this study demonstrates that when the relationship between emissions and concentrations is nonlinear, sensitivity approaches are not suitable to retrieve source contributions and source apportionment methods are not appropriate to evaluate the impact of abatement strategies. A quantification of the potential nonlinearities should therefore be the first step prior to source apportionment or planning applications, to prevent any limitations in their use. When nonlinearity is mild, these limitations may, however, be acceptable in the context of the other uncertainties inherent to complex models. Moreover, when using sensitivity analysis for planning, it is important to note that, under nonlinear circumstances, the calculated impacts will only provide information for the exact conditions (e.g. emission reduction share) that are simulated.

Photochemical grid model implementation and application of ...

EPA Pesticide Factsheets

For the purposes of developing optimal emissions control strategies, efficient approaches are needed to identify the major sources or groups of sources that contribute to elevated ozone (O3) concentrations. Source-based apportionment techniques implemented in photochemical grid models track sources through the physical and chemical processes important to the formation and transport of air pollutants. Photochemical model source apportionment has been used to track source impacts of specific sources, groups of sources (sectors), sources in specific geographic areas, and stratospheric and lateral boundary inflow on O3. The implementation and application of a source apportionment technique for O3 and its precursors, nitrogen oxides (NOx) and volatile organic compounds (VOCs), for the Community Multiscale Air Quality (CMAQ) model are described here. The Integrated Source Apportionment Method (ISAM) O3 approach is a hybrid of source apportionment and source sensitivity in that O3 production is attributed to precursor sources based on O3 formation regime (e.g., for a NOx-sensitive regime, O3 is apportioned to participating NOx emissions). This implementation is illustrated by tracking multiple emissions source sectors and lateral boundary inflow. NOx, VOC, and O3 attribution to tracked sectors in the application are consistent with spatial and temporal patterns of precursor emissions. The O3 ISAM implementation is further evaluated through comparisons of apportioned am

Ambient PM2.5 Exposure in India: Burden, Source-Apportionment and Projection Under Climate Change

NASA Astrophysics Data System (ADS)

Dey, S.; Chowdhury, S.; Upadhyay, A. K.; Smith, K. R.

2017-12-01

Air pollution has been identified as one of the leading factors of premature death in India. Absence of adequate in-situ monitors led us to use satellite retrieved aerosol optical depth (AOD) data to infer surface fine particulate matter (PM2.5). Annual premature mortality burden due to ambient PM2.5 exposure is estimated to be 1.17 (0.42-2.7) million for India. A chemical transport model WRF-Chem is utilized to estimate source-apportioned PM2.5 exposure. We estimate the exposure for four major sources - transport, residential, energy and industrial and found that the largest contribution to ambient PM2.5 exposure in India is contributed by residential sources. We estimate that if all the solid fuel use at households is replaced by clean fuel, ambient PM2.5 exposure would reduce by 30-45%, leading to 170,000 (14.5% of total burden) averted premature deaths annually. To understand how the air quality is projected to change under climate change scenarios, we analyze 13 CMIP5 models. We calculate the relative changes in PM2.5 (ensemble mean) in future relative to the baseline period (2001-2005) and apply the factor to satellite-derived PM2.5 exposure in baseline period to project future PM2.5 exposure. Ambient PM2.5 is expected to reach a maxima in 2030 under RCP4.5 (15.5% rise from baseline period) and in 2040 (25.5% rise) under RCP8.5 scenario. The projected exposure under RCP4.5 and RCP8.5 scenarios are further used to estimate premature mortality burden till the end of the century by considering population distribution projections from five shared socio-economic pathways (SSP) scenarios. We separate the burden due to ambient PM2.5 exposure in future attributable to change in meteorology due to climate change and change in demographic and epidemiological transitions. If all-India average PM2.5 exposure meets WHO interim target 1 (35 µg/m3) by 2031-40, 28000-38000 and 41100-60100 premature deaths can be averted every year under RCP4.5 and RCP8.5 respectively. Even if India fails to meet various standards, any progress towards achieving better air quality will have substantial health benefits.

Source apportionment of indoor air pollution

NASA Astrophysics Data System (ADS)

Sexton, Ken; Hayward, Steven B.

An understanding of the relative contributions from important pollutant sources to human exposures is necessary for the design and implementation of effective control strategies. In the past, societal efforts to control air pollution have focused almost exclusively on the outdoor (ambient) environment. As a result, substantial amounts of time and money have been spent to limit airborne discharges from mobile and stationary sources. Yet it is now recognized that exposures to elevated pollutant concentrations often occur as a result of indoor, rather than outdoor, emissions. While the major indoor sources have been identified, their relative impacts on indoor air quality have not been well defined. Application of existing source apportionment models to nonindustrial indoor environments is only just beginning. It is possible that these models might be used to distinguish between indoor and outdoor emissions, as well as to distinguish among indoor sources themselves. However, before the feasibility and suitability of source-apportionment methods for indoor applications can be assessed adequately, it is necessary to take account of model assumptions and associated data requirements. This paper examines the issue of indoor source apportionment and reviews the need for emission characterization studies to support such source-apportionment efforts.

Geochemistry of regional background aerosols in the Western Mediterranean

NASA Astrophysics Data System (ADS)

Pey, J.; Pérez, N.; Castillo, S.; Viana, M.; Moreno, T.; Pandolfi, M.; López-Sebastián, J. M.; Alastuey, A.; Querol, X.

2009-11-01

The chemical composition of regional background aerosols, and the time variability and sources in the Western Mediterranean are interpreted in this study. To this end 2002-2007 PM speciation data from an European Supersite for Atmospheric Aerosol Research (Montseny, MSY, located 40 km NNE of Barcelona in NE Spain) were evaluated, with these data being considered representative of regional background aerosols in the Western Mediterranean Basin. The mean PM 10, PM 2.5 and PM 1 levels at MSY during 2002-2007 were 16, 14 and 11 µg/m 3, respectively. After compiling data on regional background PM speciation from Europe to compare our data, it is evidenced that the Western Mediterranean aerosol is characterised by higher concentrations of crustal material but lower levels of OM + EC and ammonium nitrate than at central European sites. Relatively high PM 2.5 concentrations due to the transport of anthropogenic aerosols (mostly carbonaceous and sulphate) from populated coastal areas were recorded, especially during winter anticyclonic episodes and summer midday PM highs (the latter associated with the transport of the breeze and the expansion of the mixing layer). Source apportionment analyses indicated that the major contributors to PM 2.5 and PM 10 were secondary sulphate, secondary nitrate and crustal material, whereas the higher load of the anthropogenic component in PM 2.5 reflects the influence of regional (traffic and industrial) emissions. Levels of mineral, sulphate, sea spray and carbonaceous aerosols were higher in summer, whereas nitrate levels and Cl/Na were higher in winter. A considerably high OC/EC ratio (14 in summer, 10 in winter) was detected, which could be due to a combination of high biogenic emissions of secondary organic aerosol, SOA precursors, ozone levels and insolation, and intensive recirculation of aged air masses. Compared with more locally derived crustal geological dusts, African dust intrusions introduce relatively quartz-poor but clay mineral-rich silicate PM, with more kaolinitic clays from central North Africa in summer, and more smectitic clays from NW Africa in spring.

PM2.5 source apportionment in the southeastern U.S.: Spatial and seasonal variations during 2001-2005

NASA Astrophysics Data System (ADS)

Chen, Yingjun; Zheng, Mei; Edgerton, Eric S.; Ke, Lin; Sheng, Guoying; Fu, Jiamo

2012-04-01

The seasonal and spatial variations of source contributions of 112 composite fine particulate matter (PM2.5) samples collected in the Southeastern Aerosol Research and Characterization Study (SEARCH) monitoring network during 2001-2005 using molecular marker-based chemical mass balance (CMB-MM) model were determined. The lowest PM2.5 concentration occurs in January with higher values in warm months (maxima in July at four inland sites versus October at the coastal sites). Sulfate shows a similar pattern and plays a primary role in PM2.5 seasonality. Carbonaceous material (organic matter plus EC) exhibits less seasonality, but more spatial variations between the inland and coastal sites. Compared with the data at coastal sites, source attributions of diesel exhaust, gasoline exhaust, other organic matter (other OM), secondary sulfate, nitrate, and ammonium in PM2.5 mass at inland sites are higher. The difference in source attributions of wood combustion, meat cooking, vegetative detritus, and road dust among the eight sites is not significant. Contributions of eight primary sources to fine OC are wood burning (17 ± 19%), diesel exhaust (9 ± 4%), gasoline exhaust (5 ± 7%), meat cooking (5 ± 5%), road dust (2 ± 3%), vegetative detritus (2 ± 2%), cigarette smoke (2 ± 2% at four urban sites), and coke production (2 ± 1% only at BHM). Primary and secondary sources explain 82-100% of measured PM2.5 mass at the eight sites, including secondary ionic species (SO42-, NH4+, and NO3-; 41.4 ± 5.7%), identified OM (24.9 ± 11.3%), "other OM" (unexplained OM, 23.3 ± 10.3%), and "other mass" (11.4 ± 9.6%). Vehicle exhaust from both diesel and gasoline contributes the lowest fraction to PM2.5 mass in July and higher fractions at BHM and JST than other sites. Wood combustion, in contrast, contributes significantly to a larger fraction in winter than in summer. Road dust shows relatively high levels in July and April across the eight sites, while minor sources such as meat cooking and other sources (e.g., vegetative detritus, coke production, and cigarette smoke) show relatively small seasonal and spatial variations in the SEARCH monitoring network.

Chemical speciation of Fe and Ni in residual oil fly ash fine particulate matter using X-ray absorption spectroscopy.

PubMed

Pattanaik, Sidhartha; Huggins, Frank E; Huffman, Gerald P

2012-12-04

Epidemiological studies have linked residual oil fly ash fine particulate matter with aerodynamic diameter <2.5 μm (ROFA PM(2.5)) to morbidity and mortality from cardiovascular and respiratory illnesses. Bioavailable transition metals within PM have been cited as one of the components that induce such illnesses. By combining synchrotron-based X-ray absorption spectroscopy with leaching experiment, we studied the effect of residual oil compositions and combustion conditions on the speciation of Fe and Ni in ROFA PM(2.5) and the implication of these species for human health and environment. PM(2.5) samples were obtained from two types of combustors, a fire tube boiler (FTB) and a refractory line combustor (RLC). The study reveals that only Fe(2)(SO(4))(3)·nH(2)O is present in RLC PM(2.5) while Fe(2)(SO(4))(3)·nH(2)O predominates in FTB PM(2.5) with inclusion of varying amounts of nickel ferrite. The finding that RLC PM(2.5) is more bioavailable and hence more toxic than FTB PM(2.5) is significant. The reduction of toxicity of FTB PM(2.5) is due to the immobilization of a portion of Fe and Ni in the formation of an insoluble NiFe(2)O(4). This may explain the variation of toxicity from exposure to different ROFA PM(2.5). Additionally, the speciation data are sought for developing emission inventories for source apportionment study and understanding the mechanism of PM formation.

"OZONE SOURCE APPORTIONMENT IN CMAQ' | Science ...

EPA Pesticide Factsheets

Ozone source attribution has been used to support various policy purposes including interstate transport (Cross State Air Pollution Rule) by U.S. EPA and ozone nonattainment area designations by State agencies. Common scientific applications include tracking intercontinental transport of ozone and ozone precursors and delineating anthropogenic and non-anthropogenic contribution to ozone in North America. As in the public release due in September 2013, CMAQ’s Integrated Source Apportionment Method (ISAM) attributes PM EC/OC, sulfate, nitrate, ammonium, ozone and its precursors NOx and VOC, to sectors/regions of users’ interest. Although the peroxide-to-nitric acid productions ratio has been the most common indicator to distinguish NOx-limited ozone production from VOC-limited one, other indicators are implemented in addition to allowing for an ensemble decision based on a total of 9 available indicator ratios. Moreover, an alternative approach of ozone attribution based on the idea of chemical sensitivity in a linearized system that has formed the basis of chemical treatment in forward DDM/backward adjoint tools has been implemented in CMAQ. This method does not require categorization into either ozone regime. In this study, ISAM will simulate the 2010 North America ozone using all of the above gas-phase attribution methods. The results are to be compared with zero-out difference out of those sectors in the host model runs. In addition, ozone contribution wil

Chemical characteristics and source apportionment of PM2.5 in Lanzhou, China.

PubMed

Tan, Jihua; Zhang, Leiming; Zhou, Xueming; Duan, Jingchun; Li, Yan; Hu, Jingnan; He, Kebin

2017-12-01

Daily PM 2.5 samples were collected during winter 2012 and summer 2013 at an urban site in Lanzhou and were analyzed for chemical compounds including water soluble inorganic ions (WSIN), trace elements, water soluble organic carbon (WSOC), carbonaceous species (OC/EC), polycyclic aromatic hydrocarbons (PAHs), and humic-like substances (HULIS). The seasonal-average reconstructed PM 2.5 mass was 120.5μgm -3 in winter and 34.1μgm -3 in summer. The top three groups of species in PM 2.5 were OC (35.4±13.9μgm -3 ), WSIN (34.89±14.21μgm -3 ), and EC (13.80±5.41μgm -3 ) in winter and WSIN (11.25±3.25μgm -3 ), OC (9.74±3.30μgm -3 ), and EC (4.44±2.00μgm -3 ) in summer. EC exceeded SO 4 2- on most of the days. Several anthropogenic produced primary pollutants such as PAHs, Cl - , Pb, Cd and OCpri were 4-22 times higher in winter than summer. Carcinogenic substances such as Arsenic, BaP, Pb, and Cd in PM 2.5 exceeded the WHO guideline limits by 274%, 153%, 23% and 7%, respectively. Positive Matric Factorization analysis identified seven source factors including steel industry, secondary aerosols, coal combustion, power plants, vehicle emissions, crustal dust, and smelting industry, which contributed 7.1%, 33.0%, 28.7%, 3.12%, 8.8%, 13.3%, and 6.0%, respectively, to PM 2.5 in winter, and 6.7%, 14.8%, 3.1%, 3.4%, 25.2%, 11.6% and 35.2% in summer. Smelting industry and steel industry were identified for the first time as sources of PM 2.5 in this city, and power plant was distinguished from industrial boiler and residential coal burning. Copyright © 2017 Elsevier B.V. All rights reserved.

Source apportionment of PM2.5 across China using LOTOS-EUROS

NASA Astrophysics Data System (ADS)

Timmermans, R.; Kranenburg, R.; Manders, A.; Hendriks, C.; Segers, A.; Dammers, E.; Zhang, Q.; Wang, L.; Liu, Z.; Zeng, L.; Denier van der Gon, H.; Schaap, M.

2017-09-01

China's population is exposed to high levels of particulate matter (PM) due to its strong economic growth and associated urbanization and industrialization. To support policy makers to develop cost effective mitigation strategies it is of crucial importance to understand the emission sources as well as formation routes responsible for high pollution levels. In this study we applied the LOTOS-EUROS model with its module to track the contributions of predefined source sectors to China for the year 2013 using the MEIC emission inventory. It is the first application of the model system to a region outside Europe. The source attribution was aimed to provide insight in the sector and area of origin of PM2.5 for the cities of Beijing and Shanghai. The source attribution shows that on average about half of the PM2.5 pollution in both cities originates from the municipality itself. About a quarter of the PM2.5 comes from the neighbouring provinces, whereas the remaining quarter is attributed to long range transport from anthropogenic and natural components. Residential combustion, transport, and industry are identified as the main sources with comparable contributions allocated to these sectors. The importance of the sectors varies throughout the year and differs slightly between the cities. During winter, urban contributions from residential combustion are dominant, whereas industrial and traffic contributions with a larger share of regional transport are more important during summer. The evaluation of the model results against satellite and in-situ observations shows the ability of the LOTOS-EUROS model to capture many features of the variability in particulate matter and its precursors in China. The model shows a systematic underestimation of particulate matter concentrations, especially in winter. This illustrates that modelling particulate matter remains challenging as it comes to components like secondary organic aerosol and suspended dust as well as emissions and formation of PM during winter time haze situations. All in all, the LOTOS-EUROS system proves to be a powerful tool for policy support applications outside Europe as the intermediate complexity of the model allows the assessment of the area and sector of origin over decadal time periods.

Positive matrix factorization of PM2.5 - eliminating the effects of gas/particle partitioning of semivolatile organic compounds.

PubMed

Xie, M; Barsanti, K C; Hannigan, M P; Dutton, S J; Vedal, S

2013-01-01

Gas-phase concentrations of semi-volatile organic compounds (SVOCs) were calculated from gas/particle (G/P) partitioning theory using their measured particle-phase concentrations. The particle-phase data were obtained from an existing filter measurement campaign (27 January 2003-2 October 2005) as a part of the Denver Aerosol Sources and Health (DASH) study, including 970 observations of 71 SVOCs (Xie et al., 2013). In each compound class of SVOCs, the lighter species (e.g. docosane in n alkanes, fluoranthene in PAHs) had higher total concentrations (gas + particle phase) and lower particle-phase fractions. The total SVOC concentrations were analyzed using positive matrix factorization (PMF). Then the results were compared with source apportionment results where only particle-phase SVOC concentrations were used (particle only-based study; Xie et al., 2013). For the particle only-based PMF analysis, the factors primarily associated with primary or secondary sources ( n alkane, EC/sterane and inorganic ion factors) exhibit similar contribution time series ( r = 0.92-0.98) with their corresponding factors ( n alkane, sterane and nitrate+sulfate factors) in the current work. Three other factors (light n alkane/PAH, PAH and summer/odd n alkane factors) are linked with pollution sources influenced by atmospheric processes (e.g. G/P partitioning, photochemical reaction), and were less correlated ( r = 0.69-0.84) with their corresponding factors (light SVOC, PAH and bulk carbon factors) in the current work, suggesting that the source apportionment results derived from particle-only SVOC data could be affected by atmospheric processes. PMF analysis was also performed on three temperature-stratified subsets of the total SVOC data, representing ambient sampling during cold (daily average temperature < 10 °C), warm (≥ 10 °C and ≤ 20 °C) and hot (> 20 °C) periods. Unlike the particle only-based study, in this work the factor characterized by the low molecular weight (MW) compounds (light SVOC factor) exhibited strong correlations ( r = 0.82-0.98) between the full data set and each sub-data set solution, indicating that the impacts of G/P partitioning on receptor-based source apportionment could be eliminated by using total SVOC concentrations.

Physicochemical variations in atmospheric aerosols recorded at sea onboard the Atlantic-Mediterranean 2008 Scholar Ship cruise (Part II): Natural versus anthropogenic influences revealed by PM 10 trace element geochemistry

NASA Astrophysics Data System (ADS)

Moreno, Teresa; Pérez, Noemi; Querol, Xavier; Amato, Fulvio; Alastuey, Andrés; Bhatia, Ravinder; Spiro, Baruch; Hanvey, Melanie; Gibbons, Wes

2010-07-01

The geochemistry of PM 10 filter samples collected at sea during the Scholar Ship Atlantic-Mediterranean 2008 research cruise reveals a constantly changing compositional mix of pollutants into the marine atmosphere. Source apportionment modelling using Positive Matrix Factorization identifies North African desert dust, sea spray, secondary inorganic aerosols, metalliferous carbon, and V-Ni-bearing combustion particles as the main PM 10 factors/sources. The least contaminated samples show an upper continental crust composition (UCC)-normalised geochemistry influenced by seawater chemistry, with marked depletions in Rb, Th and the lighter lanthanoid elements, whereas the arrival of desert dust intrusions imposes a more upper crustal signature enriched in "geological" elements such as Si, Al, Ti, Rb, Li and Sc. Superimposed on these natural background aerosol loadings are anthropogenic metal aerosols (e.g. Cu, Zn, Pb, V, and Mn) which allow identification of pollution sources such as fossil fuel combustion, biomass burning, metalliferous industries, and urban-industrial ports. A particularly sensitive tracer is La/Ce, which rises in response to contamination from coastal FCC oil refineries. The Scholar Ship database allows us to recognise seaborne pollution sourced from NW Africa, the Cape Verde and Canary islands, and European cities and industrial complexes, plumes which in extreme cases can produce a downwind deterioration in marine air quality comparable to that seen in many cities, and can persist hundreds of kilometres from land.

Long-term trends of chemical characteristics and sources of fine particle in Foshan City, Pearl River Delta: 2008-2014.

PubMed

Tan, Jihua; Duan, Jingchun; Ma, Yongliang; He, Kebin; Cheng, Yuan; Deng, Si-Xin; Huang, Yan-Ling; Si-Tu, Shu-Ping

2016-09-15

Foshan is a major international ceramic center and the most polluted city in the Pearl River Delta (PRD). Here we present the results of the first long-term PM2.5 (particles <2.5μm) sampling and chemical characterization study of the city. A total of 2774 samples were collected at six sites from 2008 to 2014, and analyzed for water soluble species, elements and carbonaceous species. The major constituents of PM2.5 were sulfate, OC (Organic Carbon), nitrate, ammonium and EC (Elemental Carbon), which accounted for 50%-88% of PM2.5. PM2.5 and the most abundant chemical species decreased from 2008 to 2011, but rebounded in 2012-2013. After 2008, the chemical composition of PM2.5 changed dramatically due to the implementation of pollution control measures. From 2008 to 2011, SO4(2-) and NO3(-) were the two largest components; subsequently, however, OC was the largest component. The respective contributions of SO4(2-), NO3(-) and OC to the sum of water soluble species and carbonaceous species were 30.5%, 22.9% and 19.9% in 2008; and 20.2%, 16.5% and 30.2% in 2014. Distinct differences in nitrate and sulfate, and in mass ratio [NO3(-)]/[SO4(2-)] imply that mobile sources tended to more important in Foshan during 2012-2014. The results indicate that pollution control measures implemented during 2008-2014 had a large effect on anthropogenic elements (Pb, As, Cd, Zn and Cu) and water soluble species, but little influence on crustal elements (V, Mn, Ti, Ba and Fe) and carbonaceous species. The PMF method was used for source apportionment of PM2.5. Industry (including the ceramic industry and coal combustion), vehicles and dust were the three most important sources and comprised 39.2%, 20.0% and 18.4% of PM2.5 in 2008, respectively. However, secondary aerosols, vehicles and industry were the three most important sources and comprised 29.5%, 22.4% and 20.4% of PM2.5 in 2014, respectively. During the seven year study interval, the contributions of primary sources (industry and dust) decreased significantly, but secondary sources increased dramatically. Industry, dust and vehicles contributed 36.6μgm(-3), 13.9μgm(-3), and 9.2μgm(-3) to the reduction of PM2.5, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Radiocarbon-based Source Apportionment of Organic, Elemental and Water-soluble Organic Carbon Aerosols and the Light Absorption of Water-soluble Organic Carbon Aerosols in the East Asia High-intensity Winter Campaigns in 2014

NASA Astrophysics Data System (ADS)

Fang, W.; Andersson, A.; Zheng, M.; Lee, M.; Kim, S. W.; Du, K.; Gustafsson, O.

2016-12-01

Improved understanding of anthropogenic aerosol effects on atmospheric chemistry and climate as well as efficient mitigation actions are hampered by the limited comprehension of the relative contributions of different sources of carbonaceous aerosols and of their subsequent atmospheric processing. Here, we present dual carbon isotope constrained source apportionment and optical properties of carbonaceous aerosols simultaneously both at urban and rural receptor sites, includes North China Plain (NCP, Beijing and Tianjin), Yangtze River Delta (YRD, Shanghai, Zhejiang), and Jeju Island (Korea Climate Observatory at Gosan) during January 2014 field campaigns. The radiocarbon (Δ14C) data show that fossil combustions contribute equally ˜80 ± 5% to elemental carbon (EC) aerosol in Beijing, Tianjin, and Shanghai, and 66 ± 9% to Gosan-EC aerosol, while the specific sources of the dominant fossil fuel component were dramatically different among these sites. The mean fraction coal combustion of Beijing-EC, Tianjin-EC, and Gosan-EC is double that of Shanghai-EC. The other large fraction (72―92%) of carbonaceous aerosol is organic carbon (OC) aerosol which contains water soluble and water insoluble organic carbon (WSOC and WISOC). OC, WISOC, and WSOC in Beijing and Gosan sites were still observed largely from fossil sources (53―75%). The more 13C-enriched signature of Gosan-WSOC (-22.8 ± 0.2‰) compared to Gosan-EC (-23.9 ± 0.4‰) and Beijing-WSOC (-23.5 ± 0.7‰) reflects that WSOC is likely more affected by atmospheric aging during long-rang transport than is EC. The high light absorption coefficients of PM2.5, PM1, and TSP were observed at Gosan during this study and was frequently reaching 20―60 Mm-1 by aethalometer and continuous light absorption photometer. The mass absorption cross section of WSOC (MAC365) for above sites is high (1.5 ± 0.8 m2/g), accounted for ˜14 ± 5% of the total direct absorbance relative to EC, which is significantly higher than the previous findings in S. Asia, N. America, and Europe.

Proceedings from the Workshop on Research Needs for Assessment and Management of Non-Point Air Emissions from Department of Defense Activities held in Research Triangle Park, North Carolina on 19-21 February 2008

DTIC Science & Technology

2008-10-01

Chow, J.C. (2006). Feasibility of soil dust source apportionment by the pyrolysis-gas chromatography/mass spectrometry method. J. Air Waste Manage...receptor-oriented source apportionment models. • Develop monitoring methods to determine source and fence line amounts of fugitive dust emissions for...offsite impact, including evaluation with receptor- oriented source apportionment models 76 8.8.1 Background 76 8.8.2 Significance 77 8.8.3

Estimation of direct and indirect impacts of fireworks on the physicochemical characteristics of atmospheric fine and coarse particles

NASA Astrophysics Data System (ADS)

Tian, Y.-Z.; Wang, J.; Peng, X.; Shi, G.-L.; Feng, Y.-C.

2014-05-01

To quantify total, direct and indirect impacts of fireworks individually, size-resolved PM samples were collected before, during, and after a Chinese folk-custom festival (Chinese New Year) in a megacity in China. Through chemical analysis and morphology characterization, strong influence of fireworks on physicochemical characteristics of PM10 and PM2.5 was observed. Concentrations of many species exhibited an increasing trend during heavy-firework period, especially for K+, Mg2+ and Cr; and the results of non-sea-salt ions demonstrated anthropogenic influence on them. Then, source apportionment was conducted by receptor models and Peak Analysis. Total influence of fireworks was quantified by PMF, showing that fireworks contributed rather higher fractions (23.40% to PM10 and 29.66% to PM2.5) during heavy-firework period than those during light-firework period (4.28% to PM10 and 7.18% to PM2.5). Profiles of total fireworks obtained by two independent methods (PMF and Peak Analysis) were consistent, with higher abundances of K+, Al, Si, Ca and OC. Finally, individual contributions of direct and indirect impacts of fireworks were quantified by CMB. The percentage contributions of resuspended dust, biomass combustion and direct-fireworks were 36.82, 14.08 and 44.44% for PM10 and 34.89, 16.60 and 52.54% for PM2.5, in terms of the total fireworks. The quantification of total, direct and indirect impacts of fireworks to ambient PM gives an original contribution to understand the physicochemical characteristics and mechanisms of such high-intensity anthropogenic activities.

Short-term variability of mineral dust, metals and carbon emission from road dust resuspension

NASA Astrophysics Data System (ADS)

Amato, Fulvio; Schaap, Martijn; Denier van der Gon, Hugo A. C.; Pandolfi, Marco; Alastuey, Andrés; Keuken, Menno; Querol, Xavier

2013-08-01

Particulate matter (PM) pollution in cities has severe impact on morbidity and mortality of their population. In these cities, road dust resuspension contributes largely to PM and airborne heavy metals concentrations. However, the short-term variation of emission through resuspension is not well described in the air quality models, hampering a reliable description of air pollution and related health effects. In this study we experimentally show that the emission strength of resuspension varies widely among road dust components/sources. Our results offer the first experimental evidence of different emission rates for mineral dust, heavy metals and carbon fractions due to traffic-induced resuspension. Also, the same component (or source) recovers differently in a road in Barcelona (Spain) and a road in Utrecht (The Netherlands). This finding has important implications on atmospheric pollution modelling, mostly for mineral dust, heavy metals and carbon species. After rain events, recoveries were generally faster in Barcelona rather than in Utrecht. The largest difference was found for the mineral dust (Al, Si, Ca). Tyre wear particles (organic carbon and zinc) recovered faster than other road dust particles in both cities. The source apportionment of road dust mass provides useful information for air quality management.

Photochemical grid model implementation and application of VOC, NOx, and O3 source apportionment

EPA Science Inventory

For the purposes of developing optimal emissions control strategies, efficient approaches are needed to identify the major sources or groups of sources that contribute to elevated ozone (O3) concentrations. Source-based apportionment techniques implemented in photochemical grid m...

Evolution of air pollution source contributions over one decade, derived by PM10 and PM2.5 source apportionment in two metropolitan urban areas in Greece

NASA Astrophysics Data System (ADS)

Diapouli, E.; Manousakas, M.; Vratolis, S.; Vasilatou, V.; Maggos, Th; Saraga, D.; Grigoratos, Th; Argyropoulos, G.; Voutsa, D.; Samara, C.; Eleftheriadis, K.

2017-09-01

Metropolitan Urban areas in Greece have been known to suffer from poor air quality, due to variety of emission sources, topography and climatic conditions favouring the accumulation of pollution. While a number of control measures have been implemented since the 1990s, resulting in reductions of atmospheric pollution and changes in emission source contributions, the financial crisis which started in 2009 has significantly altered this picture. The present study is the first effort to assess the contribution of emission sources to PM10 and PM2.5 concentration levels and their long-term variability (over 5-10 years), in the two largest metropolitan urban areas in Greece (Athens and Thessaloniki). Intensive measurement campaigns were conducted during 2011-2012 at suburban, urban background and urban traffic sites in these two cities. In addition, available datasets from previous measurements in Athens and Thessaloniki were used in order to assess the long-term variability of concentrations and sources. Chemical composition analysis of the 2011-2012 samples showed that carbonaceous matter was the most abundant component for both PM size fractions. Significant increase of carbonaceous particle concentrations and of OC/EC ratio during the cold period, especially in the residential urban background sites, pointed towards domestic heating and more particularly wood (biomass) burning as a significant source. PMF analysis further supported this finding. Biomass burning was the largest contributing source at the two urban background sites (with mean contributions for the two size fractions in the range of 24-46%). Secondary aerosol formation (sulphate, nitrate & organics) was also a major contributing source for both size fractions at the suburban and urban background sites. At the urban traffic site, vehicular traffic (exhaust and non-exhaust emissions) was the source with the highest contributions, accounting for 44% of PM10 and 37% of PM2.5, respectively. The long-term variability of emission sources in the two cities (over 5-10 years), assessed through a harmonized application of the PMF technique on recent and past year data, clearly demonstrates the effective reduction in emissions during the last decade due to control measures and technological development; however, it also reflects the effects of the financial crisis in Greece during these years, which has led to decreased economic activities and the adoption of more polluting practices by the local population in an effort to reduce living costs.

Sophisticated Clean Air Strategies Required to Mitigate Against Particulate Organic Pollution

NASA Astrophysics Data System (ADS)

Grigas, T.; Ovadnevaite, J.; Ceburnis, D.; Moran, E.; McGovern, F. M.; Jennings, S. G.; O'Dowd, C.

2017-03-01

Since the 1980’s, measures mitigating the impact of transboundary air pollution have been implemented successfully as evidenced in the 1980-2014 record of atmospheric sulphur pollution over the NE-Atlantic, a key region for monitoring background northern-hemisphere pollution levels. The record reveals a 72-79% reduction in annual-average airborne sulphur pollution (SO4 and SO2, respectively) over the 35-year period. The NE-Atlantic, as observed from the Mace Head research station on the Irish coast, can be considered clean for 64% of the time during which sulphate dominates PM1 levels, contributing 42% of the mass, and for the remainder of the time, under polluted conditions, a carbonaceous (organic matter and Black Carbon) aerosol prevails, contributing 60% to 90% of the PM1 mass and exhibiting a trend whereby its contribution increases with increasing pollution levels. The carbonaceous aerosol is known to be diverse in source and nature and requires sophisticated air pollution policies underpinned by sophisticated characterisation and source apportionment capabilities to inform selective emissions-reduction strategies. Inauspiciously, however, this carbonaceous concoction is not measured in regulatory Air Quality networks.

Sophisticated Clean Air Strategies Required to Mitigate Against Particulate Organic Pollution.

PubMed

Grigas, T; Ovadnevaite, J; Ceburnis, D; Moran, E; McGovern, F M; Jennings, S G; O'Dowd, C

2017-03-17

Since the 1980's, measures mitigating the impact of transboundary air pollution have been implemented successfully as evidenced in the 1980-2014 record of atmospheric sulphur pollution over the NE-Atlantic, a key region for monitoring background northern-hemisphere pollution levels. The record reveals a 72-79% reduction in annual-average airborne sulphur pollution (SO 4 and SO 2 , respectively) over the 35-year period. The NE-Atlantic, as observed from the Mace Head research station on the Irish coast, can be considered clean for 64% of the time during which sulphate dominates PM 1 levels, contributing 42% of the mass, and for the remainder of the time, under polluted conditions, a carbonaceous (organic matter and Black Carbon) aerosol prevails, contributing 60% to 90% of the PM 1 mass and exhibiting a trend whereby its contribution increases with increasing pollution levels. The carbonaceous aerosol is known to be diverse in source and nature and requires sophisticated air pollution policies underpinned by sophisticated characterisation and source apportionment capabilities to inform selective emissions-reduction strategies. Inauspiciously, however, this carbonaceous concoction is not measured in regulatory Air Quality networks.

Development and application of a mobile laboratory for measuring emissions from diesel engines. 2. Sampling for toxics and particulate matter.

PubMed

Cocker, David R; Shah, Sandip D; Johnson, Kent C; Zhu, Xiaona; Miller, J Wayne; Norbeck, Joseph M

2004-12-15

Limited data are available on the emission rates of speciated volatile and semivolatile organic compounds, as well as the physical and chemical characteristics of fine particulate matter (PM) from mobile, in-use diesel engines operated on the road. A design for the sampling of these fractions and the first data from in-use diesel sources are presented in this paper. Emission rates for carbonyls, 1,3-butadiene, benzene, toluene, xylene, PM, and elemental and organic carbon (EC and OC) are reported for a vehicle driven while following the California Air Resources Board (ARB) four-mode heavy heavy-duty diesel truck (HHDDT) cycle and while transiting through a major transportation corridor. Results show that distance specific emission rates are substantially greater in congested traffic as compared with highway cruise conditions. Specifically, emissions of toxic compounds are 3-15 times greater, and PM is 7 times greater under these conditions. The dependence of these species on driving mode suggests that health and source apportionment studies will need to account for driving patterns in addition to emission factors. Comparison of the PM/NOx ratios obtained for the above tests provides insight into the presence and importance of "off-cycle" emissions during on-road driving. Measurements from a stationary source (operated and tested at constant engine speed) equipped with an engine similar to that in the HHDDT yielded a greater understanding of the relative dependence of emissions on load versus engine transients. These data are indicative of the type of investigations made possible by the development of this novel laboratory.

Modelling street level PM10 concentrations across Europe: source apportionment and possible futures

NASA Astrophysics Data System (ADS)

Kiesewetter, G.; Borken-Kleefeld, J.; Schöpp, W.; Heyes, C.; Thunis, P.; Bessagnet, B.; Terrenoire, E.; Fagerli, H.; Nyiri, A.; Amann, M.

2015-02-01

Despite increasing emission controls, particulate matter (PM) has remained a critical issue for European air quality in recent years. The various sources of PM, both from primary particulate emissions as well as secondary formation from precursor gases, make this a complex problem to tackle. In order to allow for credible predictions of future concentrations under policy assumptions, a modelling approach is needed that considers all chemical processes and spatial dimensions involved, from long-range transport of pollution to local emissions in street canyons. Here we describe a modelling scheme which has been implemented in the GAINS integrated assessment model to assess compliance with PM10 (PM with aerodynamic diameter <10 μm) limit values at individual air quality monitoring stations reporting to the AirBase database. The modelling approach relies on a combination of bottom up modelling of emissions, simplified atmospheric chemistry and dispersion calculations, and a traffic increment calculation wherever applicable. At each monitoring station fulfilling a few data coverage criteria, measured concentrations in the base year 2009 are explained to the extent possible and then modelled for the past and future. More than 1850 monitoring stations are covered, including more than 300 traffic stations and 80% of the stations which exceeded the EU air quality limit values in 2009. As a validation, we compare modelled trends in the period 2000-2008 to observations, which are well reproduced. The modelling scheme is applied here to quantify explicitly source contributions to ambient concentrations at several critical monitoring stations, displaying the differences in spatial origin and chemical composition of urban roadside PM10 across Europe. Furthermore, we analyse the predicted evolution of PM10 concentrations in the European Union until 2030 under different policy scenarios. Significant improvements in ambient PM10 concentrations are expected assuming successful implementation of already agreed legislation; however, these will not be large enough to ensure attainment of PM10 limit values in hot spot locations such as Southern Poland and major European cities. Remaining issues are largely eliminated in a scenario applying the best available emission control technologies to the maximal technically feasible extent.

Modelling street level PM10 concentrations across Europe: source apportionment and possible futures

NASA Astrophysics Data System (ADS)

Kiesewetter, G.; Borken-Kleefeld, J.; Schöpp, W.; Heyes, C.; Thunis, P.; Bessagnet, B.; Terrenoire, E.; Amann, M.

2014-07-01

Despite increasing emission controls, particulate matter (PM) has remained a critical issue for European air quality in recent years. The various sources of PM, both from primary particulate emissions as well as secondary formation from precursor gases, make this a complex problem to tackle. In order to allow for credible predictions of future concentrations under policy assumptions, a modelling approach is needed that considers all chemical processes and spatial dimensions involved, from long-range transport of pollution to local emissions in street canyons. Here we describe a modelling scheme which has been implemented in the GAINS integrated assessment model to assess compliance with PM10 (PM with aerodynamic diameter < 10 μm) limit values at individual air quality monitoring stations reporting to the AirBase database. The modelling approach relies on a combination of bottom up modelling of emissions, simplified atmospheric chemistry and dispersion calculations, and a traffic increment calculation wherever applicable. At each monitoring station fulfilling a few data coverage criteria, measured concentrations in the base year 2009 are explained to the extent possible and then modelled for the past and future. More than 1850 monitoring stations are covered, including more than 300 traffic stations and 80% of the stations which exceeded the EU air quality limit values in 2009. As a validation, we compare modelled trends in the period 2000-2008 to observations, which are well reproduced. The modelling scheme is applied here to quantify explicitly source contributions to ambient concentrations at several critical monitoring stations, displaying the differences in spatial origin and chemical composition of urban roadside PM10 across Europe. Furthermore, we analyse the predicted evolution of PM10 concentrations in the European Union until 2030 under different policy scenarios. Significant improvements in ambient PM10 concentrations are expected assuming successful implementation of already agreed legislation; however, these will not be large enough to ensure attainment of PM10 limit values in hot spot locations such as Southern Poland and major European cities. Remaining issues are largely eliminated in a scenario applying the best available emission control technologies to the maximal technically feasible extent.

Evaluation and error apportionment of an ensemble of ...

EPA Pesticide Factsheets

Through the comparison of several regional-scale chemistry transport modelling systems that simulate meteorology and air quality over the European and American continents, this study aims at i) apportioning the error to the responsible processes using time-scale analysis, ii) helping to detect causes of models error, and iii) identifying the processes and scales most urgently requiring dedicated investigations. The analysis is conducted within the framework of the third phase of the Air Quality Model Evaluation International Initiative (AQMEII) and tackles model performance gauging through measurement-to-model comparison, error decomposition and time series analysis of the models biases for several fields (ozone, CO, SO2, NO, NO2, PM10, PM2.5, wind speed, and temperature). The operational metrics (magnitude of the error, sign of the bias, associativity) provide an overall sense of model strengths and deficiencies, while apportioning the error to its constituent parts (bias, variance and covariance) can help to assess the nature and quality of the error. Each of the error components is analysed independently and apportioned to specific processes based on the corresponding timescale (long scale, synoptic, diurnal, and intra-day) using the error apportionment technique devised in the former phases of AQMEII.The application of the error apportionment method to the AQMEII Phase 3 simulations provides several key insights. In addition to reaffirming the strong impact

Aerosol carbon isotope composition over Baltic Sea

NASA Astrophysics Data System (ADS)

Garbaras, Andrius; Pabedinskas, Algirdas; Masalaite, Agne; Petelski, Tomasz; Gorokhova, Elena; Sapolaite, Justina; Ezerinskis, Zilvinas; Remeikis, Vidmantas

2017-04-01

Particulate carbonaceous matter is significant contributor to ambient particulate matter originating from intervening sources which contribution is difficult to quantify due to source diversity, chemical complexity and processes during atmospheric transport. Carbon isotope analysis can be extremely useful in source apportionment of organic matter due to the unique isotopic signatures associated with anthropocentric (fossil fuel), continental (terrestrial plants) and marine sources, and is particularly effective when these sources are mixed (Ceburnis et al., 2011;Ceburnis et al., 2016). We will present the isotope ratio measurement results of aerosol collected during the cruise in the Baltic Sea. Sampling campaign of PM10 and size segregated aerosol particles was performed on the R/V "Oceania" in October 2015. Air mass back trajectories were prevailing both from the continental and marine areas during the sampling period. The total carbon concentration varied from 1 µg/m3 to 8 µg/m3. Two end members (δ13C = -25‰ and δ13C = -28 ‰ ) were established from the total stable carbon isotope analysis in PM10 fraction. δ13C analysis in size segregated aerosol particles revealed δ13C values being highest in the 1 - 2.5 µm range (δ13C = -24.9 ‰ ) during continental transport, while lowest TC δ13C values (δ13C ≈ -27 ‰ ) were detected in the size range D50 <1 µm during stormy weather when air mass trajectory prevailed from the western direction. These measurements revealed that simplified isotope mixing model can not be applied for the aerosol source apportionment (Masalaite et al., 2015) in the perturbed marine environment. Additionally, concentration of bacteria and fungi were measured in size segregated and PM10 aerosol fraction. We were able to relate aerosol source δ13C end members with the abundance of bacteria and fungi over Baltic Sea combining air mass trajectories, stable isotope data, fungi and bacteria concentrations. Ceburnis, D., Garbaras, A., Szidat, S., Rinaldi, M., Fahrni, S., Perron, N., Wacker, L., Leinert, S., Remeikis, V., and Facchini, M.: Quantification of the carbonaceous matter origin in submicron marine aerosol by 13 C and 14 C isotope analysis, Atmospheric Chemistry and Physics, 11, 8593-8606, 2011. Ceburnis, D., Masalaite, A., Ovadnevaite, J., Garbaras, A., Remeikis, V., Maenhaut, W., Claeys, M., Sciare, J., Baisnée, D., and O'Dowd, C. D.: Stable isotopes measurements reveal dual carbon pools contributing to organic matter enrichment in marine aerosol, Scientific Reports, 6, 2016. Masalaite, A., Remeikis, V., Garbaras, A., Dudoitis, V., Ulevicius, V., and Ceburnis, D.: Elucidating carbonaceous aerosol sources by the stable carbon δ13C TC ratio in size-segregated particles, Atmospheric Research, 158, 1-12, 2015.

Source contributions to United States ozone and particulate matter over five decades from 1970 to 2020

NASA Astrophysics Data System (ADS)

Nopmongcol, Uarporn; Alvarez, Yesica; Jung, Jaegun; Grant, John; Kumar, Naresh; Yarwood, Greg

2017-10-01

Evaluating long-term air quality trends can demonstrate effectiveness of control strategies and guide future air quality management planning. Observations have shown that ozone (O3) and fine particulate matter (PM2.5) in the US have declined since as early as 1980 in some areas. But observation trends alone cannot separate effects of changes in local and global emissions to US air quality which are important to air quality planners. This study uses a regional model (CAMx) nested within a global model (GEOS-Chem) to characterize regional changes in O3 and PM2.5 due to the intercontinental transport and local/regional emissions representing six modeling years within five decades (1970-2020). We use the CAMx Source Apportionment Technology (OSAT/PSAT) to estimate contributions from 6 source sectors in 7 source regions plus 6 other groups for a total of 48 tagged contributions. On-road mobile sources consistently make the largest U.S. anthropogenic emissions contribution to O3 in all cities examined even though they decline substantially from 1970 to 2005 and also from 2005 to 2020. Off-road mobile source contributions increase from 1970 to 2005 and then decrease after 2005 in all of the cities. The boundary conditions, mostly from intercontinental transport, contribute more than 20 ppb to high maximum daily 8-h average (MDA8) O3 for all six years. We found that lowering NOx emissions raises O3 formation efficiency (OFE) across all emission categories which will limit potential O3 benefits of local NOx strategies in the near future. PM2.5 benefited from adoption of control devices between 1970 and 1980 and has continued to decline through 2005 and expected to decline further by 2020. Area sources such as residential, commercial and fugitive dust emissions stand out as making large contributions to PM2.5 that are not declining. Inter-regional transport is less important in 2020 than 1990 for both pollutants.

Meteorological-gaseous influences on seasonal PM2.5 variability in the Klang Valley urban-industrial environment

NASA Astrophysics Data System (ADS)

Amil, N.; Latif, M. T.; Khan, M. F.; Mohamad, M.

2015-09-01

This study attempts to investigate the fine particulate matter (PM2.5) variability in the Klang Valley urban-industrial environment. In total, 94 daily PM2.5 samples were collected during a one-year campaign from August 2011 to July 2012, covering all four seasons. The samples were analysed for various inorganic components and black carbon. The chemical compositions were statistically analysed and the aerosol pattern was characterised using descriptive analysis, correlation matrices, enrichment factors (EF), stoichiometric analysis and chemical mass closure (CMC). For source apportionment purposes, a combination of positive matrix factorisation (PMF) and multi-linear regression (MLR) was employed. Further, meteorological-gaseous parameters were incorporated into each analysis for improved assessment. The results showed that PM2.5 mass averaged at 28 ± 18 μg m-3, 2.8 fold higher than the World Health Organisation (WHO) annual guideline. On a daily basis, the PM2.5 mass ranged between 6 and 118 μg m-3 with 43 % exceedance of the daily WHO guideline. The North-East monsoon (NE) was the only season with < 50 % sample exceedance of the daily WHO guideline. On an annual scale, PM2.5 mass correlated positively with temperature (T) and wind speed (WS) but negatively with relative humidity (RH). With the exception of NOx, the gases analysed (CO, NO2, NO and SO2) were found to significantly influence the PM2.5 mass. Seasonal variability unexpectedly showed that rainfall, WS and wind direction (WD) did not significantly correlate with PM2.5 mass. Further analysis on the PM2.5 / PM10, PM2.5 / TSP and PM10 / TSP ratios reveal that meteorological parameters only greatly influenced the coarse particles (PM > 2.5μm) and less so the fine particles at the site. Chemical composition showed that both primary and secondary pollutants of PM2.5 are equally important, albeit with seasonal variability. The CMC components identified were: black carbon (BC) > secondary inorganic aerosols (SIA) > dust > trace elements (TE) > sea salt > K+. The EF analysis distinguished two groups of trace elements: those with anthropogenic sources (Pb, Se, Zn, Cd, As, Bi, Ba, Cu, Rb, V and Ni) and those with a crustal source (Sr, Mn, Co and Li). The five identified factors resulting from PMF 5.0 were: (1) combustion of engine oil; (2) mineral dust; (3) mixed SIA and biomass burning; (4) mixed traffic and industrial; and (5) sea salt. Each of these sources had an annual mean contribution of 17, 14, 42, 10 and 17 %, respectively. The dominance of each identified source largely varied with changing season and a few factors were in agreement with the CMC, EF and stoichiometric analysis, accordingly. In relation to meteorological-gaseous parameters, PM2.5 sources were influenced by different parameters during different seasons. In addition, two air pollution episodes (HAZE) revealed the influence of local and/or regional sources. Overall, our study clearly suggests that the chemical constituents and sources of PM2.5 were greatly influenced and characterised by meteorological and gaseous parameters which largely vary with season.

Water Soluble Organic Nitrogen (WSON) in Ambient Fine Particles Over a Megacity in South China: Spatiotemporal Variations and Source Apportionment

NASA Astrophysics Data System (ADS)

Yu, Xu; Yu, Qingqing; Zhu, Ming; Tang, Mingjin; Li, Sheng; Yang, Weiqiang; Zhang, Yanli; Deng, Wei; Li, Guanghui; Yu, Yuegang; Huang, Zhonghui; Song, Wei; Ding, Xiang; Hu, Qihou; Li, Jun; Bi, Xinhui; Wang, Xinming

2017-12-01

Organic nitrogen aerosols are complex mixtures and important compositions in ambient fine particulate matters (PM2.5), yet their sources and spatiotemporal patterns are not well understood particularly in regions influenced by intensive human activities. In this study, filter-based ambient PM2.5 samples at four stations (one urban, two rural, plus one urban roadside) and PM samples from combustion sources (vehicle exhaust, ship emission, and biomass burning) were collected in the coastal megacity Guangzhou, south China, for determining water soluble organic nitrogen (WSON) along with other organic and inorganic species. The annual average WSON concentrations, as well as the ratios of WSON to water soluble total nitrogen, were all significantly higher at rural sites than urban sites. Average WSON concentrations at the four sites during the wet season were quite near each other, ranging from 0.41 to 0.49 μg/m3; however, they became 2 times higher at the rural sites than at the urban sites during the dry season. Five major sources for WSON were identified through positive matrix factorization analysis. Vehicle emission (29.3%), biomass burning (22.8%), and secondary formation (20.2%) were three dominant sources of WSON at the urban station, while vehicle emission (45.4%) and dust (28.6%) were two dominant sources at the urban roadside station. At the two rural sites biomass burning (51.1% and 34.1%, respectively) and secondary formation (17.8% and 30.5%, respectively) were dominant sources of WSON. Ship emission contributed 8-12% of WSON at the four sites. Natural vegetation seemed to have very minor contribution to WSON.

SOURCE APPORTIONMENT OF EXPOSURES TO VOLATILE ORGANIC COMPOUNDS: I. EVALUATION OF RECEPTOR MODELS USING SIMULATED EXPOSURE DATA. (R826788)

EPA Science Inventory

Four receptor-oriented source apportionment models were evaluated by applying them to simulated personal exposure data for select volatile organic compounds (VOCs) that were generated by Monte Carlo sampling from known source contributions and profiles. The exposure sources mo...

76 FR 12847 - Public Road Mileage for Apportionment of Highway Safety Funds; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-09

... FHWA are from 8 a.m. to 4:30 p.m., e.t., Monday through Friday, except Federal holidays. SUPPLEMENTARY..., Puerto Rico, the Virgin Islands, Guam, American Samoa, and the Commonwealth of the Northern Mariana...

Chemical composition, structural properties, and source apportionment of organic macromolecules in atmospheric PM10 in a coastal city of Southeast China.

PubMed

Chen, Yanting; Du, Wenjiao; Chen, Jinsheng; Hong, Youwei; Zhao, Jinping; Xu, Lingling; Xiao, Hang

2017-02-01

Particulate matter (PM 10 ) associated with the fractions of organic macromolecules, including humic acid (HA), kerogen + black carbon (KB), and black carbon (BC), was determined during summer and winter at urban and suburban sites in a coastal city of southeast China. The organic macromolecules were characterized by elemental analysis (EA), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR), and their sources were identified by using stable carbon/nitrogen isotope (δ 13 C/δ 15 N) and the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) Model. The results showed that HA, kerogen (K), and BC accounted for the range of 3.89 to 4.55 % in PM 10 , while they were the dominant fractions of total organic carbon (TOC), ranging from 64.70 to 84.99 %. SEM analysis indicated that BC particles were porous/nonporous and consisted of spherical and non-spherical (i.e., cylindrical and elongate) structures. The FTIR spectra of HA, KB, and BC exhibited similar functional groups, but the difference of various sites and seasons was observed. HA in PM 10 contained a higher fraction of aliphatic structures, such as long-chain fatty and carbohydrates with a carboxylic extremity. The C/N ratio, SEM, and δ 13 C/δ 15 N values provided reliable indicators of the sources of HA, K, and BC in PM 10 . The results suggested that HA and K majorly originated from terrestrial plants, and BC came from the mixture of combustion of terrestrial plants, fossil fuel, and charcoal. The air masses in winter originated from Mongolia (4 %), the northern area of China (48 %), and northern adjacent cities (48 %), suggesting the influence of anthropogenic sources through long-range transport, while the air masses for the summer period came from South China Sea (34 %) and Western Pacific Sea (66 %), representing clean marine air masses with low concentrations of organic macromolecules.

Emissions of PAHs derived from sugarcane burning and processing in Chiapas and Morelos México.

PubMed

Mugica-Alvarez, Violeta; Santiago-de la Rosa, Naxieli; Figueroa-Lara, Jesús; Flores-Rodríguez, Julio; Torres-Rodríguez, Miguel; Magaña-Reyes, Miguel

2015-09-15

Sugarcane burning is an agricultural practice implemented to ease farm worker duties; nevertheless, as a consequence, tons of particles are emitted to the atmosphere. Additionally, during harvesting the sugar-mills operate the whole day emitting hundreds of tons of pollutants. Therefore, health risks to neighboring population should be a major governmental concern, leading first to identification and quantification of toxic compounds, such as polycyclic aromatic hydrocarbons (PAHs). In order to establish the magnitude of the problem, four sampling campaigns of PM10 and PM2.5 were carried out in this study, during harvesting and no-harvesting seasons in two municipalities of México, with different climatic and social conditions. Concentrations of PM10, PM2.5, and organic compounds were determined daily, followed by extraction, identification and quantification of the 17 EPA-established PAHs from all samples. The results showed that during harvest, the PM10 mass increased lightly in Chiapas, but approximately twice in Morelos, whereas total PAH concentrations increased twice and six times, respectively. The most abundant PAHs, namely: indene [1,2,3cd] pyrene, benzo[b]fluoranthene, benzo[a]pyrene and dibenzo [a,h] anthracene are composed of 5 or more aromatic rings. Of the total PAHs quantified, 44% to 52% corresponded to carcinogenic compounds, consequently, the overall carcinogenic potential increased twice or three times. Principal component analysis with varimax rotation was applied to source apportionment at each site, suggesting three different sources during harvesting: the combustion process in the sugar mill, sugarcane burning and vehicular emissions. The combustion markers for sugar mill are, BAA, BBF, BKF, BAP, IND and BGP, whereas for sugarcane burning were ANT, PHE, FLT and PYR. The results obtained indicate that processing and burning sugarcane are the main sources of the PAH levels measured, proving that the health risks are boosted during harvesting due to increases of PM and PAHs. Copyright © 2015 Elsevier B.V. All rights reserved.

Source apportionment of PM10 and PM2.5 in major urban Greek agglomerations using a hybrid source-receptor modeling process.

PubMed

Argyropoulos, G; Samara, C; Diapouli, E; Eleftheriadis, K; Papaoikonomou, K; Kungolos, A

2017-12-01

A hybrid source-receptor modeling process was assembled, to apportion and infer source locations of PM 10 and PM 2.5 in three heavily-impacted urban areas of Greece, during the warm period of 2011, and the cold period of 2012. The assembled process involved application of an advanced computational procedure, the so-called Robotic Chemical Mass Balance (RCMB) model. Source locations were inferred using two well-established probability functions: (a) the Conditional Probability Function (CPF), to correlate the output of RCMB with local wind directional data, and (b) the Potential Source Contribution Function (PSCF), to correlate the output of RCMB with 72h air-mass back-trajectories, arriving at the receptor sites, during sampling. Regarding CPF, a higher-level conditional probability function was defined as well, from the common locus of CPF sectors derived for neighboring receptor sites. With respect to PSCF, a non-parametric bootstrapping method was applied to discriminate the statistically significant values. RCMB modeling showed that resuspended dust is actually one of the main barriers for attaining the European Union (EU) limit values in Mediterranean urban agglomerations, where the drier climate favors build-up. The shift in the energy mix of Greece (caused by the economic recession) was also evidenced, since biomass burning was found to contribute more significantly to the sampling sites belonging to the coldest climatic zone, particularly during the cold period. The CPF analysis showed that short-range transport of anthropogenic emissions from urban traffic to urban background sites was very likely to have occurred, within all the examined urban agglomerations. The PSCF analysis confirmed that long-range transport of primary and/or secondary aerosols may indeed be possible, even from distances over 1000km away from study areas. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of polar organic compounds and source analysis of fine organic aerosols in Hong Kong

NASA Astrophysics Data System (ADS)

Li, Yunchun

Organic aerosols, as an important fraction of airborne particulate mass, significantly affect the environment, climate, and human health. Compared with inorganic species, characterization of individual organic compounds is much less complete and comprehensive because they number in thousands or more and are diverse in chemical structures. The source contributions of organic aerosols are far from being well understood because they can be emitted from a variety of sources as well as formed from photochemical reactions of numerous precursors. This thesis work aims to improve the characterization of polar organic compounds and source apportionment analysis of fine organic carbon (OC) in Hong Kong, which consists of two parts: (1) An improved analytical method to determine monocarboxylic acids, dicarboxylic acids, ketocarboxylic acids, and dicarbonyls collected on filter substrates has been established. These oxygenated compounds were determined as their butyl ester or butyl acetal derivatives using gas chromatography-mass spectrometry. The new method made improvements over the original Kawamura method by eliminating the water extraction and evaporation steps. Aerosol materials were directly mixed with the BF 3/BuOH derivatization agent and the extracting solvent hexane. This modification improves recoveries for both the more volatile and the less water-soluble compounds. This improved method was applied to study the abundances and sources of these oxygenated compounds in PM2.5 aerosol samples collected in Hong Kong under different synoptic conditions during 2003-2005. These compounds account for on average 5.2% of OC (range: 1.4%-13.6%) on a carbon basis. Oxalic acid was the most abundant species. Six C2 and C3 oxygenated compounds, namely oxalic, malonic, glyoxylic, pyruvic acids, glyoxal, and methylglyoxal, dominated this suite of oxygenated compounds. More efforts are therefore suggested to focus on these small compounds in understanding the role of oxygenated compounds in aerosol chemistry and physics. By reference to tracers for the major organic aerosol sources, it is deduced that the oxygenated compounds are mainly of secondary origin and direct/indirect contribution from biomass burning could also be important. The chemical composition of these oxygenated species in PM2.5 samples in Hong Kong provide useful information to further ambient and model study in the aspects of chemical formation pathways and speciated organic mass distribution. (2) Source apportionment of PM2.5 organic aerosols in Hong Kong were carried out in two studies. In the first study, chemical characterization and source analysis involved samples collected on high particulate matter (PM) days (avg. PM 2.5 >84 mug m-3) at six general stations and one roadside station from October to December in 2003. Analysis of synoptic weather conditions identified three types of high PM episodes: local, regional transport (RT) and long-range transport (LRT). Roadside samples were discussed separately. Using chemical mass balance (CMB) model, contributions of major primary sources (vehicle exhaust, cooking, biomass burning, cigarette smoke, vegetative detritus, and coal combustion) were estimated, which indicate that vehicle exhaust was the most important primary source, followed by cooking and biomass burning. All primary sources except vegetative detritus had the highest contributions at roadside station, in line with its site characteristics. Primary sources dominated roadside and local samples (>64% of fine OC), while un-apportioned OC (i.e., the difference between measured OC and apportioned primary OC) dominated RT and LRT episodes (>60% of fine OC) and un-apportioned OC had characteristics of secondary OC. In the second study, cold front episodes during winter 2004 and 2005 were targeted to investigate the effect of cold front-related LRT on chemical characteristics and organic aerosol sources of PM2.5 in Hong Kong. In comparison with days under influences of mainly local emissions or RT, cold front LRT brought more organic aerosols attributable to coal combustion and biomass burning. Both cold front episodes and RT brought in significant amount of secondary OC to Hong Kong. The relative abundances of major aerosol constituents (sulfate, nitrate, ammonium, organic matter, and elemental carbon) were similar in cold front periods and RT-dominated periods.

Source Apportionment of Final Particulate Matterin North China Plain based on Air Quality Modeling

NASA Astrophysics Data System (ADS)

Xing, J.; Wu, W.; Chang, X.; Wang, S.; Hao, J.

2016-12-01

Most Chinese cities in North China Plain are suffering from serious air pollution. To develop the regional air pollution control policies, we need to identify the major source contributions to such pollution and to design the control policy which is accurate, efficient and effective. This study used the air quality model with serval advanced technologies including ISAM and ERSM, to assess the source contributions from individual pollutants (incl. SO2, NOx, VOC, NH3, primary PM), sectors (incl. power plants, industry, transportation and domestic), and regions (Beijing, Hebei, Tianjing and surrounding provinces). The modeling period is two months in 2012 as January and July which represent winter and summer respectively. The non-linear relationship between air pollutant emissions and air quality will be addressed, and the integrated control of multi-pollutants and multi-regions in China will be suggested.

Health effects caused by primary fine particulate matter (PM2.5) emitted from buses in the Helsinki metropolitan area, Finland.

PubMed

Tainio, Marko; Tuomisto, Jouni T; Hänninen, Otto; Aarnio, Päivi; Koistinen, Kimmo J; Jantunen, Matti J; Pekkanen, Juha

2005-02-01

Fine particle (PM(2.5)) emissions from traffic have been associated with premature mortality. The current work compares PM(2.5)-induced mortality in alternative public bus transportation strategies as being considered by the Helsinki Metropolitan Area Council, Finland. The current bus fleet and transportation volume is compared to four alternative hypothetical bus fleet strategies for the year 2020: (1) the current bus fleet for 2020 traffic volume, (2) modern diesel buses without particle traps, (3) diesel buses with particle traps, and (4) buses using natural gas engines. The average population PM(2.5) exposure level attributable to the bus emissions was determined for the 1996-1997 situation using PM(2.5) exposure measurements including elemental composition from the EXPOLIS-Helsinki study and similar element-based source apportionment of ambient PM(2.5) concentrations observed in the ULTRA study. Average population exposure to particles originating from the bus traffic in the year 2020 is assumed to be proportional to the bus emissions in each strategy. Associated mortality was calculated using dose-response relationships from two large cohort studies on PM(2.5) mortality from the United States. Estimated number of deaths per year (90% confidence intervals in parenthesis) associated with primary PM(2.5) emissions from buses in Helsinki Metropolitan Area in 2020 were 18 (0-55), 9 (0-27), 4 (0-14), and 3 (0-8) for the strategies 1-4, respectively. The relative differences in the associated mortalities for the alternative strategies are substantial, but the number of deaths in the lowest alternative, the gas buses, is only marginally lower than what would be achieved by diesel engines equipped with particle trap technology. The dose-response relationship and the emission factors were identified as the main sources of uncertainty in the model.

Enterococcus and Escherichia coli fecal source apportionment with microbial source tracking genetic markers - is it feasible?

EPA Science Inventory

Fecal pollution is measured in surface waters using culture-based measurements of enterococci and Escherichia coli bacteria. Source apportionment of these two fecal indicator bacteria is an urgent need for prioritizing remediation efforts and quantifying health risks associated...

Characterization of the wintertime particulate (PM1) pollution at an urban background site of Nicosia, Cyprus

NASA Astrophysics Data System (ADS)

Pikridas, Michael; Sciare, Jean; Vrekoussis, Mihalis; Oikonomou, Konstantina; Merabet, Hamza; Mihalopoulos, Nikos; Yassaa, Nouredine; Savvides, Chrysanthos

2016-04-01

As part of MISTRALS-ChArMEx (Chemistry-Aerosol Mediterranean Experiment, http://charmex.lsce.ipsl.fr/), and MISTRALS-ENVI-Med "CyAr" (Cyprus Aerosols and gas precursors) programs, a 1-month intensive field campaign has been performed in December 2014 at an urban background site of Nicosia (Cyprus) - a typical European city of the Eastern Mediterranean - with the objective to document the major (local versus imported) sources responsible for wintertime particulate (PM1) pollution. Several near real-time analyzers were deployed for that purpose (TEOM 1400, OPC Grimm 1.108, Q-ACSM, Aethalometer AE31) allowing to investigate in near-real time the major chemical components of submicron aerosols (Black Carbon, Organics, Sulphate, Nitrate, Ammonium). Quality control of Q-ACSM and Aethalometer datasets was performed through closure studies (using co-located TEOM / OPC Grimm). Comparisons were also performed with other on-line / off-line measurements performed by the local Air quality network (DLI) at other locations in Nicosia with the objective to check the consistency and representativeness of our observations. Very high levels of Black Carbon and OA were systematically observed every night (with maximum concentrations around 22:00 local time) pointing to local combustion sources most probably related to domestic heating. Source apportionment of organic aerosols (OA) was performed using the SourceFinder software (SoFi, http://www.psi.ch/acsm-stations/me-2) allowing the distinction between various primary/secondary OA sources and helped us to better characterize the combustion sources being responsible for the observed elevated nighttime PM1 levels. Acknowledgements: This campaign has been funded by MISTRALS (ChArMEx et ENVI-Med CyAr programs), CNRS-INSU, CEA, CyI, DLI, CDER and ECPL.

Indoor air quality at life and work environments in Rome, Italy.

PubMed

Romagnoli, P; Balducci, C; Perilli, M; Vichi, F; Imperiali, A; Cecinato, A

2016-02-01

The air quality of three different microenvironments (school, dwelling, and coffee bar) located in the city of Rome, Italy, was assessed. Indoor and outdoor concentrations of polycyclic aromatic hydrocarbons (PAHs) associated with PM2.5 particles were determined during an intensive 3-week sampling campaign conducted in March 2013. In interiors, total particulate PAHs ranged from 1.53 to 4.96 ng/m(3) while outdoor air contained from 2.75 to 3.48 ng/m(3). In addition, gaseous toxicants, i.e., NO2, NOx , SO2, O3, and BTEX (benzene, toluene, ethyl-benzene, and xylene isomers), were determined both in internal and external air. To solve the origin of indoor and outdoor PAHs, several source apportionment methods were applied. Multivariate analysis revealed that emissions from motor vehicles, biomass burning for heating purposes, and soil resuspension were the major sources of PAHs in the city. No linear correlation was established between indoor and outdoor values for PM2.5 and BTEX; the respective indoor/outdoor concentration ratios exceed unity except for PM2.5 in the no smoking home and benzene in all school floors. This suggests that important internal sources such as tobacco smoking, cleaning products, and resuspension dust contributed to indoor pollution. Using the monitoring stations of ARPA Lazio regional network as reference, the percentage within PAH group of benzo[a]pyrene, which is the WHO marker for the carcinogenic risk estimates, was ca. 50% higher in all locations investigated.

Trace element contents in fine particulate matter (PM2.5) in urban school microenvironments near a contaminated beach with mine tailings, Chañaral, Chile.

PubMed

Mesías Monsalve, Stephanie; Martínez, Leonardo; Yohannessen Vásquez, Karla; Alvarado Orellana, Sergio; Klarián Vergara, José; Martín Mateo, Miguel; Costilla Salazar, Rogelio; Fuentes Alburquenque, Mauricio; Cáceres Lillo, Dante D

2018-06-01

Air quality in schools is an important public health issue because children spend a considerable part of their daily life in classrooms. Particulate size and chemical composition has been associated with negative health effects. We studied levels of trace element concentrations in fine particulate matter (PM 2.5 ) in indoor versus outdoor school settings from six schools in Chañaral, a coastal city with a beach severely polluted with mine tailings. Concentrations of trace elements were measured on two consecutive days during the summer and winter of 2012 and 2013 and determined using X-ray fluorescence. Source apportionment and element enrichment were measured using principal components analysis and enrichment factors. Trace elements were higher in indoor school spaces, especially in classrooms compared with outdoor environments. The most abundant elements were Na, Cl, S, Ca, Fe, K, Mn, Ti, and Si, associated with earth's crust. Conversely, an extremely high enrichment factor was determined for Cu, Zn, Ni and Cr; heavy metals associated with systemic and carcinogenic risk effects, whose probably origin sources are industrial and mining activities. These results suggest that the main source of trace elements in PM 2.5 from these school microenvironments is a mixture of dust contaminated with mine tailings and marine aerosols. Policymakers should prioritize environmental management changes to minimize further environmental damage and its direct impact on the health of children exposed.

Source apportionment of speciated PM2.5 over Halifax, Nova Scotia, during BORTAS-B, using pragmatic mass closure and principal component analysis

NASA Astrophysics Data System (ADS)

Gibson, Mark D.; Kuchta, James; Chisholm, Lucy; Duck, Tom; Hopper, Jason; Beauchamp, Stephen; Waugh, David; King, Gavin; Pierce, Jeffrey; Li, Zhengyan; Leaitch, Richard; Ward, Tony J.; Haelssig, Jan; Palmer, Paul I.

2013-04-01

During BORTAS-B, 42 days of contiguous PM2.5 filter samples were collected during the summer of 2011 in Halifax, Nova Scotia. The aim of the PM2.5 filter sampling was to apportion the source contribution to the total PM2.5 mass concentration in Halifax to inform and validate other surface measurements and chemical transport models related to BORTAS-B. Sampling was conducted on the roof of a Dalhousie University building at a height of 15 m. The building is located in a residential area of Halifax. Continuous black carbon (BC) was measured using a Magee AE-42 aethalometer. Continuous organic carbon was measured using an Aerodyne, Aerosol Chemical Speciation Monitor. Daily teflon filter samples were collected for the determination of fine particulate with a median aerodynamic diameter less than or equal to 2.5 microns (PM2.5). An additional, daily, nylon filter was used for the determination of PM2.5 cations and anions by IC. The PM2.5 teflon filter was analysed for 33 metals by XRF and 10 trace metals by ICP-MS. The biomass burning marker levoglucosan was analysed by GC-MS following derivatization. Excellent agreement (R2 = 0.88) was observed between continuous and filter based measurements with a gradient of 2.76. The median (min : max) PM2.5 mass concentration during BORTAS-B = 3.9 (0.08 : 13.7) μg-m3. The median (min : max) continuous BC = 0.39 (0.12 : 1.03); SO4 = 0.47 (0.14 : 5.59); NO3 = 0.067 (0.007 : 0.64); OC = 0.77 (0.18 : 2.77); NH4 = 0.15 (0:003 : 1.45); Cl = 0.011 (0.0019 : 0.32); Fe = 0.018 (0.0011 : 0.097); Al = 0.011 (0.0091 : 0.086); Si = 0.03 (0.0044 : 0.29); V = 0.0026 (0.0016 : 0.017) and Ni = 0.0007 (0.0005 : 0.0037) μg-m3 respectively. Absolute principal component scores (APCS) and pragmatic mass closure (PMC) will be used to identify the sources driving the observed PM2.5 variability over Halifax, during BORTAS-B. A comparison of APCS and PMC PM2.5 receptor model output results will be presented. These model data will provide further insight into the source contribution to summertime surface PM2.5 mass in Halifax, Nova Scotia, Canada.

Dispersion model on PM₂.₅ fugitive dust and trace metals levels in Kuwait Governorates.

PubMed

Bu-Olayan, A H; Thomas, B V

2012-03-01

Frequent dust storms and recent environmental changes were found to affect the human health especially in residents of arid countries. Investigations on the PM(2.5) fugitive dust in six Kuwait Governorate areas using dispersion Gaussian plume modeling revealed significant relationship between low rate of pollutant emission, low wind velocity, and stable weather conditions' matrix causing high rate of dust deposition in summer than in winter. The rate of dust deposition and trace metals levels in PM(2.5) were in the sequence of G-VI > G-I > G-II > G-V > G-III > G-IV. Trace metals were observed in the sequence of Al > Fe > Zn > Ni > Pb > Cd irrespective of the Governorate areas and the two seasons. The high rate of dust deposition and trace metals in PM(2.5) was reflected by the vast open area, wind velocity, and rapid industrialization besides natural and anthropogenic sources. A combination of air dispersion modeling and nephalometric and gravimetric studies of this kind not only determines the seasonal qualitative and quantitative analyses on the PM(2.5) dust deposition besides trace metals apportionment in six Kuwait Governorate areas, but also characterizes air pollution factors that could be used by environmentalist to deduce preventive measures.

Particulate pollutants in the Brazilian city of São Paulo: 1-year investigation for the chemical composition and source apportionment

NASA Astrophysics Data System (ADS)

Martins Pereira, Guilherme; Teinilä, Kimmo; Custódio, Danilo; Gomes Santos, Aldenor; Xian, Huang; Hillamo, Risto; Alves, Célia A.; Bittencourt de Andrade, Jailson; Olímpio da Rocha, Gisele; Kumar, Prashant; Balasubramanian, Rajasekhar; de Fátima Andrade, Maria; de Castro Vasconcellos, Pérola

2017-10-01

São Paulo in Brazil has relatively relaxed regulations for ambient air pollution standards and often experiences high air pollution levels due to emissions of particulate pollutants from local sources and long-range transport of air masses impacted by biomass burning. In order to evaluate the sources of particulate air pollution and related health risks, a year-round sampling was done at the University of São Paulo campus (20 m a.g.l.), a green area near an important expressway. The sampling was performed for PM2. 5 ( ≤ 2. 5 µm) and PM10 ( ≤ 10 µm) in 2014 through intensive (everyday sampling in wintertime) and extensive campaigns (once a week for the whole year) with 24 h of sampling. This year was characterized by having lower average precipitation compared to meteorological data, and high-pollution episodes were observed all year round, with a significant increase in pollution level in the intensive campaign, which was performed during wintertime. Different chemical constituents, such as carbonaceous species, polycyclic aromatic hydrocarbons (PAHs) and derivatives, water-soluble ions, and biomass burning tracers were identified in order to evaluate health risks and to apportion sources. The species such as PAHs, inorganic and organic ions, and monosaccharides were determined using chromatographic techniques and carbonaceous species using thermal-optical analysis. Trace elements were determined using inductively coupled plasma mass spectrometry. The risks associated with particulate matter exposure based on PAH concentrations were also assessed, along with indexes such as the benzo[a]pyrene equivalent (BaPE) and lung cancer risk (LCR). High BaPE and LCR were observed in most of the samples, rising to critical values in the wintertime. Also, biomass burning tracers and PAHs were higher in this season, while secondarily formed ions presented low variation throughout the year. Meanwhile, vehicular tracer species were also higher in the intensive campaign, suggesting the influence of lower dispersion conditions in that period. Source apportionment was performed using positive matrix factorization (PMF), which indicated five different factors: road dust, industrial emissions, vehicular exhaust, biomass burning and secondary processes. The results highlighted the contribution of vehicular emissions and the significant input from biomass combustion in wintertime, suggesting that most of the particulate matter is due to local sources, in addition to the influence of pre-harvest sugarcane burning.

Spatial/Temporal Variations of Elemental Carbon, Organic Carbon, and Trace Elements in PM10 and the Impact of Land-Use Patterns on Community Air Pollution in Paterson, NJ

PubMed Central

Yu, Chang Ho; Fan, Zhi-Hua; Meng, Qingyu; Zhu, Xianlei; Korn, Leo; Bonanno, Linda J.

2014-01-01

An urban community PM10 (particulate matter ≤ 10 μm in aerodynamic diameter) air pollution study was conducted in Paterson, NJ, a mixed land-use community that is interspersed with industrial, commercial, mobile, and residential land-use types. This paper examines (1) the spatial/temporal variation of PM10, elemental carbon (EC), organic carbon (OC), and nine elements; and (2) the impact of land-use type on those variations. Air samples were collected from three community-oriented locations in Paterson that attempted to capture industrial, commercial, and mobile source-dominated emissions. Sampling was conducted for 24 hr every 6 days from November 2005 through December 2006. Samples were concurrently collected at the New Jersey Department of Environmental Protection-designated air toxics background site in Chester, NJ. PM10 mass, EC, OC, and nine elements (Ca, Cu, Fe, Pb, Mn, Ni, S, Ti, and Zn) that had more than 50% of samples above detection and known sources or are toxic were selected for spatial/temporal analysis in this study. The concentrations of PM10, EC, OC, and eight elements (except S) were significantly higher in Paterson than in Chester (P < 0.05). The concentrations of these elements measured in Paterson were also found to be higher during winter than the other three seasons (except S), and higher on weekdays than on weekends (except Pb). The concentrations of EC, Cu, Fe, and Zn at the commercial site in Paterson were significantly higher than the industrial and mobile sites; however, the other eight species were not significantly different within the city (P > 0.05). These results indicated that anthropogenic sources of air pollution were present in Paterson. The source apportionment confirmed the impact of vehicular and industrial emissions on the PM10 ambient air pollution in Paterson. The multiple linear regression analysis showed that categorical land-use type was a significant predictor for all air pollution levels, explaining up to 42% of the variability in concentration by land-use type only. PMID:21751583

Climate change air toxic co-reduction in the context of macroeconomic modelling.

PubMed

Crawford-Brown, Douglas; Chen, Pi-Cheng; Shi, Hsiu-Ching; Chao, Chia-Wei

2013-08-15

This paper examines the health implications of global PM reduction accompanying greenhouse gas emissions reductions in the 180 national economies of the global macroeconomy. A human health effects module based on empirical data on GHG emissions, PM emissions, background PM concentrations, source apportionment and human health risk coefficients is used to estimate reductions in morbidity and mortality from PM exposures globally as co-reduction of GHG reductions. These results are compared against the "fuzzy bright line" that often underlies regulatory decisions for environmental toxics, and demonstrate that the risk reduction through PM reduction would usually be considered justified in traditional risk-based decisions for environmental toxics. It is shown that this risk reduction can be on the order of more than 4 × 10(-3) excess lifetime mortality risk, with global annual cost savings of slightly more than $10B, when uniform GHG reduction measures across all sectors of the economy form the basis for climate policy ($2.2B if only Annex I nations reduce). Consideration of co-reduction of PM-10 within a climate policy framework harmonized with other environmental policies can therefore be an effective driver of climate policy. An error analysis comparing results of the current model against those of significantly more spatially resolved models at city and national scales indicates errors caused by the low spatial resolution of the global model used here may be on the order of a factor of 2. Copyright © 2013 Elsevier Ltd. All rights reserved.

Source contributions of fine particulate matter during one winter haze episodes in Xi'an, China

NASA Astrophysics Data System (ADS)

Yang, X.; Wu, Q.

2017-12-01

Long-term exposure to high levels of fine particulate matter (PM2.5) is found to be associated with adverse effects on human health, ecological environment and climate change. Identification the major source regions of fine particulate matter are essential to proposing proper joint prevention and control strategies for heavy haze mitigation. In this work, the Comprehensive Air Quality Model with extensions (CAMx) together with the Particulate Source Apportionment Technology (PSAT) and the Weather Research and Forecast Model (WRF), have been applied to analyze the major source regions of PM2.5 in Xi'an during the heavy haze episodes in winter (29, December, 2016 - 5 January 2017), and the framework of the model system is shown in Fig. 1. Firstly, according to the model evaluation of the daily PM2.5 concentrations for the two months, the model has well performance, and the fraction of predictions within a factor of 2 of the observations (FAC2) is 84%, while the correlation coefficient (R) is 0.80 in Xi'an. By using the PSAT in CAMx model, a detailed source region contribution matrix is derived for all points within the Xi'an region and its six surrounding areas, and long-range regional transport. The results show that the local emission in Xi'an is the mainly sources at downtown area, which contributing 72.9% as shown in Fig.2, and the contribution rate of transportations between adjacent areas depends on wind direction. Meanwhile, three different suburban areas selected for detailed analysis in fine particles sources. Comparing to downtown area, the sources of suburban areas are more multiply, and the transportations make the contribution 40%-82%. In the suburban areas, regional inflows play an important role in the fine particles concentrations, indicating a strong need for regional joint emission control efforts. The results enhance the quantitative understanding of the PM2.5 source regions and provide a basis for policymaking to advance the control of pollution in Xi'an, China.

Improve regional distribution and source apportionment of PM2.5 trace elements in China using inventory-observation constrained emission factors.

PubMed

Ying, Qi; Feng, Miao; Song, Danlin; Wu, Li; Hu, Jianlin; Zhang, Hongliang; Kleeman, Michael J; Li, Xinghua

2018-05-15

Contributions to 15 trace elements in airborne particulate matter with aerodynamic diameters <2.5μm (PM 2.5 ) in China from five major source sectors (industrial sources, residential sources, transportation, power generation and windblown dust) were determined using a source-oriented Community Multiscale Air Quality (CMAQ) model. Using emission factors in the composite speciation profiles from US EPA's SPECIATE database for the five sources leads to relatively poor model performance at an urban site in Beijing. Improved predictions of the trace elements are obtained by using adjusted emission factors derived from a robust multilinear regression of the CMAQ predicted primary source contributions and observation at the urban site. Good correlations between predictions and observations are obtained for most elements studied with R>0.5, except for crustal elements Al, Si and Ca, particularly in spring. Predicted annual and seasonal average concentrations of Mn, Fe, Zn and Pb in Nanjing and Chengdu are also consistently improved using the adjusted emission factors. Annual average concentration of Fe is as high as 2.0μgm -3 with large contributions from power generation and transportation. Annual average concentration of Pb reaches 300-500ngm -3 in vast areas, mainly from residential activities, transportation and power generation. The impact of high concentrations of Fe on secondary sulfate formation and Pb on human health should be evaluated carefully in future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

A Handbook for Determining the Sources of PCB Contamination in Sediments

DTIC Science & Technology

2012-10-01

identifying sources for initial source control to later use for remedial cost apportionment . Often, forensic investigations are successfully used to...alteration processes, source apportionment can be difficult. For instance, one can easily imagine an onshore spill or source of PCB oil that results in a...the use of Aroclor analyses for identifying contamination sources to only fresh samples (for example, PCB oils or soils with freshly spilled PCB

Monitoring of air pollution levels related to Charilaos Trikoupis Bridge.

PubMed

Sarigiannis, D A; Handakas, E J; Kermenidou, M; Zarkadas, I; Gotti, A; Charisiadis, P; Makris, K; Manousakas, M; Eleftheriadis, K; Karakitsios, S P

2017-12-31

Charilaos Trikoupis bridge is the longest cable bridge in Europe that connects Western Greece with the rest of the country. In this study, six air pollution monitoring campaigns (including major regulated air pollutants) were carried out from 2013 to 2015 at both sides of the bridge, located in the urban areas of Rio and Antirrio respectively. Pollution data were statistically analyzed and air quality was characterized using US and European air quality indices. From the overall campaign, it was found that air pollution levels were below the respective regulatory thresholds, but once at the site of Antirrio (26.4 and 52.2μg/m 3 for PM 2.5 and ΡΜ 10 , respectively) during the 2nd winter period. Daily average PM 10 and PM 2.5 levels from two monitoring sites were well correlated to gaseous pollutant (CO, NO, NO 2 , NO x and SO 2 ) levels, meteorological parameters and factor scores from Positive Matrix Factorization during the 3-year period. Moreover, the elemental composition of PM 10 and PM 2.5 was used for source apportionment. That analysis revealed that major emission sources were sulfates, mineral dust, biomass burning, sea salt, traffic and shipping emissions for PM 10 and PM 2.5 , for both Rio and Antirrio. Seasonal variation indicates that sulfates, mineral dust and traffic emissions increased during the warm season of the year, while biomass burning become the dominant during the cold season. Overall, the contribution of the Charilaos Trikoupis bridge to the vicinity air pollution is very low. This is the result of the relatively low daily traffic volume (~10,000 vehicles per day), the respective traffic fleet composition (~81% of the traffic fleet are private vehicles) and the speed limit (80km/h) which does not favor traffic emissions. In addition, the strong and frequent winds further contribute to the rapid dispersion of the emitted pollutants. Copyright © 2017. Published by Elsevier B.V.

Guidance Document for PMF Applications with the Multilinear Engine

EPA Science Inventory

This document serves as a guide for users of the Multilinear Engine version 2 (ME-2) for source apportionment applications utilizing positive matrix factorization (PMF). It aims to educate experienced source apportionment analysts on available ME rotational tools and provides gui...

Sophisticated Clean Air Strategies Required to Mitigate Against Particulate Organic Pollution

PubMed Central

Grigas, T.; Ovadnevaite, J.; Ceburnis, D.; Moran, E.; McGovern, F. M.; Jennings, S. G.; O’Dowd, C.

2017-01-01

Since the 1980’s, measures mitigating the impact of transboundary air pollution have been implemented successfully as evidenced in the 1980–2014 record of atmospheric sulphur pollution over the NE-Atlantic, a key region for monitoring background northern-hemisphere pollution levels. The record reveals a 72–79% reduction in annual-average airborne sulphur pollution (SO4 and SO2, respectively) over the 35-year period. The NE-Atlantic, as observed from the Mace Head research station on the Irish coast, can be considered clean for 64% of the time during which sulphate dominates PM1 levels, contributing 42% of the mass, and for the remainder of the time, under polluted conditions, a carbonaceous (organic matter and Black Carbon) aerosol prevails, contributing 60% to 90% of the PM1 mass and exhibiting a trend whereby its contribution increases with increasing pollution levels. The carbonaceous aerosol is known to be diverse in source and nature and requires sophisticated air pollution policies underpinned by sophisticated characterisation and source apportionment capabilities to inform selective emissions-reduction strategies. Inauspiciously, however, this carbonaceous concoction is not measured in regulatory Air Quality networks. PMID:28303958

Integrated assessment of air pollution by metals and source apportionment using ryegrass (Lolium multiflorum Lam.) in southern Brazil.

PubMed

Illi, Júlia Carolina; Vancetta, Tafael; Alves, Darlan Daniel; Osório, Daniela Montanari Migliavacca; Bianchin, Liane; de Quevedo, Daniela Müller; Juchem, Fernando

2017-01-01

One of the biggest environmental problems existing today is air pollution, which is characterized by the presence of toxic gases and metal pollutants, the latter of which is generally associated with emissions of particulate matter (PM) from industries or automotive vehicles. Biomonitoring is a method that can be used to assess air pollution levels because it makes it possible to determine what effects these air pollutants cause in living organisms and their responses. The species Lolium multiflorum Lam., known as ryegrass, is considered a good bioindicator of metals, since it accumulates these substances during exposure. This study proposes to conduct an integrated assessment of air quality using two different monitoring methodologies: biomonitoring with L. multiflorum and active monitoring in areas with different levels of urbanization and industrialization. Concentrations found in ryegrass plants revealed high levels of Pb, Cr, Zn, and Cu, indicating that vehicular and industrial emissions were the main sources of pollution. Analysis of PM also revealed soot and biogenic particles, which can transport metals. Therefore, with the proposed method, the anthropogenic impact on air pollution in the investigated area could be clearly demonstrated.

Chemical characterization of fine organic aerosol for source apportionment at Monterrey, Mexico

NASA Astrophysics Data System (ADS)

Mancilla, Y.; Mendoza, A.; Fraser, M. P.; Herckes, P.

2015-07-01

Primary emissions from anthropogenic and biogenic sources as well as secondary formation are responsible for the pollution levels of ambient air in major urban areas. These sources release fine particles into the air that negatively impact human health and the environment. Organic molecular markers, which are compounds that are unique to specific PM2.5 sources, can be utilized to identify the major emission sources in urban areas. In this study, 43 representative PM2.5 samples, for both daytime and nighttime periods, were built from individual samples collected in an urban site of the Monterrey Metropolitan Area (MMA) during the spring and fall of 2011 and 2012. The samples were analyzed for organic carbon, elemental carbon, and organic molecular markers. Several diagnostic tools were employed for the preliminary identification of emission sources. Organic compounds for eight compound classes were quantified. The n-alkanoic acids were the most abundant, followed by n-alkanes, wood smoke markers, and levoglucosan/alkenoic acids. Polycyclic aromatic hydrocarbons (PAHs) and hopanes were less abundant. The carbon preference index (0.7-2.6) for n-alkanes indicate a major contribution of anthropogenic and mixed sources during the fall and the spring, respectively. Hopanes levels confirmed the contribution from gasoline and diesel engines. In addition, the contribution of gasoline and diesel vehicle exhaust was confirmed and identified by the PAH concentrations in PM2.5. Diagnostic ratios of PAH showed emissions from burning coal, wood, biomass, and other fossil fuels. The total PAH and elemental carbon (EC) were correlated (r2 = 0.39-0.70) across the monitoring periods, reinforcing that motor vehicles are the major contributors of PAH. Cholesterol levels remained constant during the spring and fall, showing evidence of the contribution of meat cooking operations, while the isolated concentrations of levoglucosan suggested occasional biomass burning events. Finally, source attribution results obtained using the CMB model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5. The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5). To our knowledge, this is the second study to explore the broad chemical characterization of fine organic aerosol in Mexico and the first for the MMA.

Seasonal variability of PM2.5 composition and sources in the Klang Valley urban-industrial environment

NASA Astrophysics Data System (ADS)

Amil, Norhaniza; Talib Latif, Mohd; Firoz Khan, Md; Mohamad, Maznorizan

2016-04-01

This study investigates the fine particulate matter (PM2.5) variability in the Klang Valley urban-industrial environment. In total, 94 daily PM2.5 samples were collected during a 1-year campaign from August 2011 to July 2012. This is the first paper on PM2.5 mass, chemical composition and sources in the tropical environment of Southeast Asia, covering all four seasons (distinguished by the wind flow patterns) including haze events. The samples were analysed for various inorganic components and black carbon (BC). The chemical compositions were statistically analysed and the temporal aerosol pattern (seasonal) was characterised using descriptive analysis, correlation matrices, enrichment factor (EF), stoichiometric analysis and chemical mass closure (CMC). For source apportionment purposes, a combination of positive matrix factorisation (PMF) and multi-linear regression (MLR) was employed. Further, meteorological-gaseous parameters were incorporated into each analysis for improved assessment. In addition, secondary data of total suspended particulate (TSP) and coarse particulate matter (PM10) sampled at the same location and time with this study (collected by Malaysian Meteorological Department) were used for PM ratio assessment. The results showed that PM2.5 mass averaged at 28 ± 18 µg m-3, 2.8-fold higher than the World Health Organisation (WHO) annual guideline. On a daily basis, the PM2.5 mass ranged between 6 and 118 µg m-3 with the daily WHO guideline exceeded 43 % of the time. The north-east (NE) monsoon was the only season with less than 50 % sample exceedance of the daily WHO guideline. On an annual scale, PM2.5 mass correlated positively with temperature (T) and wind speed (WS) but negatively with relative humidity (RH). With the exception of NOx, the gases analysed (CO, NO2, NO and SO2) were found to significantly influence the PM2.5 mass. Seasonal variability unexpectedly showed that rainfall, WS and wind direction (WD) did not significantly correlate with PM2.5 mass. Further analysis on the PM2.5 / PM10, PM2.5 / TSP and PM10 / TSP ratios reveal that meteorological parameters only greatly influenced the coarse particles (particles with an aerodynamic diameter of greater than 2.5 µm) and less so the fine particles at the site. Chemical composition showed that both primary and secondary pollutants of PM2.5 are equally important, albeit with seasonal variability. The CMC components identified were in the decreasing order of (mass contribution) BC > secondary inorganic aerosols (SIA) > dust > trace elements > sea salt > K+. The EF analysis distinguished two groups of trace elements: those with anthropogenic sources (Pb, Se, Zn, Cd, As, Bi, Ba, Cu, Rb, V and Ni) and those with a crustal source (Sr, Mn, Co and Li). The five identified factors resulting from PMF 5.0 were (1) combustion of engine oil, (2) mineral dust, (3) mixed SIA and biomass burning, (4) mixed traffic and industrial and (5) sea salt. Each of these sources had an annual mean contribution of 17, 14, 42, 10 and 17 % respectively. The dominance of each identified source largely varied with changing season and a few factors were in agreement with the CMC, EF and stoichiometric analysis, accordingly. In relation to meteorological-gaseous parameters, PM2.5 sources were influenced by different parameters during different seasons. In addition, two air pollution episodes (HAZE) revealed the influence of local and/or regional sources. Overall, our study clearly suggests that the chemical constituents and sources of PM2.5 were greatly influenced and characterised by meteorological and gaseous parameters which vary greatly with season.

Concentration characteristics, source apportionment, and oxidative damage of PM2.5-bound PAHs in petrochemical region in Xinjiang, NW China.

PubMed

Turap, Yusan; Talifu, Dilinuer; Wang, Xinming; Aierken, Tuergong; Rekefu, Suwubinuer; Shen, Hao; Ding, Xiang; Maihemuti, Mailikezhati; Tursun, Yalkunjan; Liu, Wei

2018-05-30

Polycyclic aromatic hydrocarbons (PAHs) are of considerable concern due to their potential as human carcinogens. Thus, determining the characteristics, potential source, and examining the oxidative capacity of PAHs to protect human health is essential. This study investigated the PM 2.5 -bound PAHs at Dushanzi, a large petrochemical region in Xinjiang as well as northwest China. A total of 33 PM 2.5 samples with 13 PAHs, together with molecular tracers (levoglucosan, and element carbon), were analyzed during the non-heating and heating periods. The results showed that the PM 2.5 concentrations were 70.22 ± 22.30 and 95.47 ± 61.73 μg/m 3 , while that of total PAHs were 4.07 ± 2.03 and 60.33 ± 30.80 ng/m 3 in sampling period, respectively. The fluoranthene, pyrene, chrysene, benzo[b]fluoranthene, and benzo[k]fluoranthene were the most abundant (top five) PAHs, accounting for 71.74 and 72.80% of total PAH mass during non-heating and heating periods. The BaP equivalent (BaPeq) concentration exceeded 1 ng/m 3 as recommended by National Ambient Air Quality Standards during heating period. The diagnostic ratios and positive matrix factorization indicated that oil industry, biomass burning, coal combustion, and vehicle emissions are the primary sources. The coal combustion remarkably increased during heating period. The plasmid scission assay (PSA) results showed that higher DNA damage rate was observed during heating period. PAHs in PM 2.5 such as Chr, BaP, and IcdP were found to have significantly positive correlations with the plasmid DNA damage rates. Additionally, the relationship among BaPeq and DNA damage rate suggested that synergistic reaction may modify the toxicity of PAHs.

Seasonal and spatial variation of organic tracers for biomass burning in PM1 aerosols from highly insolated urban areas.

PubMed

van Drooge, B L; Fontal, M; Bravo, N; Fernández, P; Fernández, M A; Muñoz-Arnanz, J; Jiménez, B; Grimalt, J O

2014-10-01

PM1 aerosol characterization on organic tracers for biomass burning (levoglucosan and its isomers and dehydroabietic acid) was conducted within the AERTRANS project. PM1 filters (N = 90) were sampled from 2010 to 2012 in busy streets in the urban centre of Madrid and Barcelona (Spain) at ground-level and at roof sites. In both urban areas, biomass burning was not expected to be an important local emission source, but regional emissions from wildfires, residential heating or biomass removal may influence the air quality in the cities. Although both areas are under influence of high solar radiation, Madrid is situated in the centre of the Iberian Peninsula, while Barcelona is located at the Mediterranean Coast and under influence of marine atmospheres. Two extraction methods were applied, i.e. Soxhlet and ASE, which showed equivalent results after GC-MS analyses. The ambient air concentrations of the organic tracers for biomass burning increased by an order of magnitude at both sites during winter compared to summer. An exception was observed during a PM event in summer 2012, when the atmosphere in Barcelona was directly affected by regional wildfire smoke and levels were four times higher as those observed in winter. Overall, there was little variation between the street and roof sites in both cities, suggesting that regional biomass burning sources influence the urban areas after atmospheric transport. Despite the different atmospheric characteristics in terms of air relative humidity, Madrid and Barcelona exhibit very similar composition and concentrations of biomass burning organic tracers. Nevertheless, levoglucosan and its isomers seem to be more suitable for source apportionment purposes than dehydroabietic acid. In both urban areas, biomass burning contributions to PM were generally low (2 %) in summer, except on the day when wildfire smoke arrive to the urban area. In the colder periods the contribution increase to around 30 %, indicating that regional biomass burning has a substantial influence on the urban air quality.

Understanding the PM2.5 imbalance between a far and near-road location: Results of high temporal frequency source apportionment and parameterization of black carbon

NASA Astrophysics Data System (ADS)

Sofowote, U. M.; Healy, R. M.; Su, Y.; Debosz, J.; Noble, M.; Munoz, A.; Jeong, C.-H.; Wang, J. M.; Hilker, N.; Evans, G. J.; Hopke, P. K.

2018-01-01

The differences in PM2.5 concentrations between two relatively close stations, one situated near a major highway and the other much more distant were used to develop a protocol for determining the impact of highway traffic on particulate matter concentrations at the roadside. The roadside station was <15 m away from the edge of a major highway while the other was located ∼170 m away. The roadside station contains a suite of continuous instrumentation capable of near-real-time speciation of PM2.5. The particulate matter difference, formally termed the PM2.5 imbalance was arbitrarily defined as a case wherein |Near-road PM2.5 - Far from road PM2.5|/Near-road PM2.5 ≳50%. Of interest was the variation of multi-time factors based on ME2 analyses of the speciation data from the roadside station during these imbalance events. Of the 7 mass-contributing ME2 factors, a black carbon factor was determined to be the major cause of the PM2.5 imbalance and was especially dominant for the case when PM2.5 concentrations at the roadside station were greater than the farther-station PM2.5. The black carbon concentrations observed during these specific events were further regressed against other traffic-related and meteorological parameters with two nonlinear optimization algorithms (generalized reduced gradient and rules ensemble) in our attempts to model any potential relationships. It was observed that the traffic counts of heavy duty vehicles (predominantly diesel-powered) dominated the relationship with black carbon while contributions from light duty vehicles were negligible during these [PM2.5]Roadside > [PM2.5]Farther events at the roadside station. This work details the most critical ways that highway traffic can contribute to local ambient PM2.5 concentrations that commuters are exposed to and will be important in informing policies and strategies for particulate matter pollution reduction.

Air pollution dispersion models for human exposure predictions in London.

PubMed

Beevers, Sean D; Kitwiroon, Nutthida; Williams, Martin L; Kelly, Frank J; Ross Anderson, H; Carslaw, David C

2013-01-01

The London household survey has shown that people travel and are exposed to air pollutants differently. This argues for human exposure to be based upon space-time-activity data and spatio-temporal air quality predictions. For the latter, we have demonstrated the role that dispersion models can play by using two complimentary models, KCLurban, which gives source apportionment information, and Community Multi-scale Air Quality Model (CMAQ)-urban, which predicts hourly air quality. The KCLurban model is in close agreement with observations of NO(X), NO(2) and particulate matter (PM)(10/2.5), having a small normalised mean bias (-6% to 4%) and a large Index of Agreement (0.71-0.88). The temporal trends of NO(X) from the CMAQ-urban model are also in reasonable agreement with observations. Spatially, NO(2) predictions show that within 10's of metres of major roads, concentrations can range from approximately 10-20 p.p.b. up to 70 p.p.b. and that for PM(10/2.5) central London roadside concentrations are approximately double the suburban background concentrations. Exposure to different PM sources is important and we predict that brake wear-related PM(10) concentrations are approximately eight times greater near major roads than at suburban background locations. Temporally, we have shown that average NO(X) concentrations close to roads can range by a factor of approximately six between the early morning minimum and morning rush hour maximum periods. These results present strong arguments for the hybrid exposure model under development at King's and, in future, for in-building models and a model for the London Underground.

Chemical characteristics and source of size-fractionated atmospheric particle in haze episode in Beijing

NASA Astrophysics Data System (ADS)

Tan, Jihua; Duan, Jingchun; Zhen, Naijia; He, Kebin; Hao, Jiming

2016-01-01

The abundance, behavior, and source of chemical species in size-fractionated atmospheric particle were studied with a 13-stage low pressure impactor (ELPI) during high polluted winter episode in Beijing. Thirty three elements (Al, Ca, Fe, K, Mg, Na, Si, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Sr, Zr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, and Pb) and eight water soluble ions (Cl-, NO3-, SO42 -, NH4+, Na+, K+, Ca2 +, and Mg2 +) were determined by ICP/MS and IC, respectively. The size distribution of TC (OC + EC) was reconstructed. Averagely, 51.5 ± 5.3% and 74.1 ± 3.7% of the total aerosol mass was distributed in the sub-micron (PM1) and fine particle (PM2.5), respectively. A significant shift to larger fractions during heavy pollution episode was observed for aerosol mass, NH4+, SO42 -, NO3-, K, Fe, Cu, Zn, Cd, and Pb. The mass size distributions of NH4+, SO42 -, NO3-, and K were dominated by accumulation mode. Size distributions of elements were classified into four main types: (I) elements were enriched within the accumulation mode (< 1 μm, Ge, Se, Ag, Sn, Sb, Cs, Hg, Ti, and Pb); (II) those mass (K, Cr, Mn, Cu, Zn, As, Mo, and Cd) was resided mainly within the accumulation mode, ranged from 1 to 2 μm; (III) Na, V, Co, Ni, and Ga were distributed among fine, intermediate, and coarse modes; and (IV) those which were mainly found within particles larger than 2.7 μm (Al, Mg, Si, Ca, Sc, Tl, Fe, Sr, Zr, and Ba). [H+]cor showed an accumulation mode at 600-700 nm and the role of Ca2 + should be fully considered in the estimation of acidity. The acidity in accumulation mode particles suggested that generally gaseous NH3 was not enough to neutralize sulfate completely. PMF method was applied for source apportionment of elements combined with water soluble ions. Dust, vehicle, aged coal combustion, and sea salt were identified, and the size resolved source apportionments were discussed. Aged coal combustion was the important source of fine particles and dust contributed most to coarse particle.

Chemical characterization and source apportionment of PM2.5 aerosols in a megacity of Southeast China

NASA Astrophysics Data System (ADS)

Li, Huiming; Wang, Qin'geng; Yang, Meng; Li, Fengying; Wang, Jinhua; Sun, Yixuan; Wang, Cheng; Wu, Hongfei; Qian, Xin

2016-11-01

PM2.5 aerosol samples were collected during a haze-fog event in winter, as well as in spring, summer, and fall in 2013 within an urban area (Xianlin) and city center area (Gulou) of Nanjing, a megacity of SE China. The PM2.5 showed typical seasonality of waxing in winter and waning in summer or fall with annual average concentrations of 145 and 139 μg/m3 in Xianlin and Gulou, respectively. Concentrations of SO42 -, NO3-, NH4+, Cl-, and K+, EC, OC, secondary organic carbon, and most elements were elevated in winter. The sulfur oxidation ratio and concentrations of SO42 - and Cl- were significantly higher in Xianlin than Gulou (p < 0.05), whereas the nitrogen oxidation ratio and NO3- concentrations were significantly higher in Gulou than Xianlin (p < 0.05). A chemical mass closure construction was used to apportion PM2.5 fractions. Using the positive matrix factorization model, six source factors were identified as having contributed to PM2.5. These were secondary nitrate, road dust, sea salt and ship emissions, coal combustion, secondary sulfate, and the iron and steel industry, which contributed annual averages of 17.8 ± 15.1, 10.6 ± 9.53, 4.50 ± 3.28, 12.4 ± 9.82, 46.3 ± 14.4, and 8.42 ± 5.15%, respectively, to the PM2.5 mass in Xianlin, and 34.5 ± 16.2, 7.82 ± 7.21, 7.27 ± 5.61, 10.5 ± 9.35, 33.0 ± 16.6, and 7.00 ± 6.1%, respectively, in Gulou. Distinct seasonal patterns of the source factors in the two areas associated with the main chemical components were identified, which could be explained by various sources and meteorological conditions. Fig. S2 Temporal trends of sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR) in all four seasons in Xianlin (a) and Gulou (b). Fig. S3 The OC/EC ratios found in four seasons in Xianlin (a) and Gulou (b). Fig. S4 The enrichment factors (EF) obtained in four seasons in Xianlin (a) and Gulou (b). Fig. S5 Estimated versus observed PM2.5 mass concentrations during sampling period in the two areas (95% confidence interval).

Estimation of the local and long-range contributions to particulate matter levels using continuous measurements in a single urban background site

NASA Astrophysics Data System (ADS)

Diamantopoulou, Marianna; Skyllakou, Ksakousti; Pandis, Spyros N.

2016-06-01

The Particulate Matter Source Apportionment Technology (PSAT) algorithm is used together with PMCAMx, a regional chemical transport model, to develop a simple observation-based method (OBM) for the estimation of local and regional contributions of sources of primary and secondary pollutants in urban areas. We test the hypothesis that the minimum of the diurnal average concentration profile of the pollutant is a good estimate of the average contribution of long range transport levels. We use PMCAMx to generate "pseudo-observations" for four different European cities (Paris, London, Milan, and Dusseldorf) and PSAT to estimate the corresponding "true" local and regional contributions. The predictions of the proposed OBM are compared to the "true" values for different definitions of the source area. During winter, the estimates by the OBM for the local contributions to the concentrations of total PM2.5, primary pollutants, and sulfate are within 25% of the "true" contributions of the urban area sources. For secondary organic aerosol the OBM overestimates the importance of the local sources and it actually estimates the contributions of sources within 200 km from the receptor. During summer for primary pollutants and cities with low nearby emissions (ratio of emissions in an area extending 100 km from the city over local emissions lower than 10) the OBM estimates correspond to the city emissions within 25% or so. For cities with relatively high nearby emissions the OBM estimates correspond to emissions within 100 km from the receptor. For secondary PM2.5 components like sulfate and secondary organic aerosol the OBM's estimates correspond to sources within 200 km from the receptor. Finally, for total PM2.5 the OBM provides approximately the contribution of city emissions during the winter and the contribution of sources within 100 km from the receptor during the summer.

Source apportionment of fine particulate matter organic carbon in Shenzhen, China by chemical mass balance and radiocarbon methods.

PubMed

Al-Naiema, Ibrahim M; Yoon, Subin; Wang, Yu-Qin; Zhang, Yuan-Xun; Sheesley, Rebecca J; Stone, Elizabeth A

2018-09-01

Chemical mass balance (CMB) modeling and radiocarbon measurements were combined to evaluate the sources of carbonaceous fine particulate matter (PM 2.5 ) in Shenzhen, China during and after the 2011 summer Universiade games when air pollution control measurements were implemented to achieve air quality targets. Ambient PM 2.5 filter samples were collected daily at two sampling sites (Peking University Shenzhen campus and Longgang) over 24 consecutive days, covering the controlled and uncontrolled periods. During the controlled period, the average PM 2.5 concentration was less than half of what it was after the controls were lifted. Organic carbon (OC), organic molecular markers (e.g., levoglucosan, hopanes, polycyclic aromatic hydrocarbons), and secondary organic carbon (SOC) tracers were all significantly lower during the controlled period. After pollution controls ended, at Peking University, OC source contributions included gasoline and diesel engines (24%), coal combustion (6%), biomass burning (12.2%), vegetative detritus (2%), biogenic SOC (from isoprene, α-pinene, and β-caryophyllene; 7.1%), aromatic SOC (23%), and other sources not included in the model (25%). At Longgang after the controls ended, similar source contributions were observed: gasoline and diesel engines (23%), coal combustion (7%), biomass burning (17.7%), vegetative detritus (1%), biogenic SOC (from isoprene, α-pinene, and β-caryophyllene; 5.3%), aromatic SOC (13%), and other sources (33%). The contributions of the following sources were smaller during the pollution controls: biogenic SOC (by a factor of 10-16), aromatic SOC (4-12), coal combustion (1.5-6.8), and biomass burning (2.3-4.9). CMB model results and radiocarbon measurements both indicated that fossil carbon dominated over modern carbon, regardless of pollution controls. However, the CMB model needs further improvement to apportion contemporary carbon (i.e. biomass burning, biogenic SOC) in this region. This work defines the major contributors to carbonaceous PM 2.5 in Shenzhen and demonstrates that control measures for primary emissions could significantly reduce secondary organic aerosol (SOA) formation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Estimation of the direct and indirect impacts of fireworks on the physicochemical characteristics of atmospheric PM10 and PM2.5

NASA Astrophysics Data System (ADS)

Tian, Y. Z.; Wang, J.; Peng, X.; Shi, G. L.; Feng, Y. C.

2014-09-01

To quantify the total, direct and indirect impacts of fireworks individually, size-resolved PM samples were collected before, during and after a Chinese folk festival (Chinese New Year) in a megacity in China. Through chemical analysis and morphological characterisation, a strong influence of fireworks on the physicochemical characteristics of PM10 and PM2.5 was observed. The concentrations of many species exhibited an increasing trend during the heavy-firework period, especially for K+, Mg2+ and Cr; the results of the non-sea-salt ions demonstrated an anthropogenic influence on K+ and Mg2+. Then, source apportionment was conducted by receptor models and peak analysis (PA). The total influence of the fireworks was quantified by positive matrix factorisation (PMF), showing that the fireworks contributed higher fractions (23.40% for PM10 and 29.66% for PM2.5) during the heavy-firework period than during the light-firework period (4.28% for PM10 and 7.18% for PM2.5). The profiles of the total fireworks obtained by two independent methods (PMF and peak analysis) were consistent, with higher abundances of K+, Al, Si, Ca and organic carbon (OC). Finally, the individual contributions of the direct and indirect impacts of fireworks were quantified by chemical mass balance (CMB). The percentage contributions of resuspended dust, biomass combustion and direct fireworks were 36.8 ± 8.37%, 14.1 ± 2.82% and 44.4 ± 8.26%, respectively, for PM10 and 34.9 ± 4.19%, 16.6 ± 3.05% and 52.5 ± 9.69%, respectively, for PM2.5, in terms of the total fireworks. The quantification of the total, direct and indirect impacts of fireworks in the ambient PM gives a original contribution for understanding the physicochemical characteristics and mechanisms of such high-intensity anthropogenic activities.

Apportionment of Primary and Secondary Organic Aerosols in Southern California During the 2005 Study of Organic Aerosols in Riverside (SOAR-1)

EPA Science Inventory

Ambient sampling was conducted in Riverside, California during the 2005 Study of Organic Aerosols in Riverside to characterize the composition and sources of organic aerosol using a variety of state-of-the-art instrumentation and source apportionment techniques.

SOURCE APPORTIONMENT OF EXPOSURES TO VOLATILE ORGANIC COMPOUNDS: II. APPLICATION OF RECEPTOR MODELS TO TEAM STUDY DATA. (R826788)

EPA Science Inventory

Four receptor-oriented source apportionment models were applied to personal exposure measurements for toxic volatile organic compounds (VOCs). The measurements are from the total exposure assessment methodology studies conducted from 1980 to 1984 in New Jersey (NJ) and Califor...

Synthesizing Scientific Progress: Outcomes from US EPA’s Carbonaceous Aerosols and Source Apportionment STAR Grants

EPA Science Inventory

ABSTRACTA number of studies in the past decade have transformed the way we think about atmospheric aerosols. The advances include, but are not limited to, source apportionment of organics using aerosol mass spectrometer data, the volatility basis set approach, quantifying isopre...

Regional transport, source apportionment and health impact of PM10 bound polycyclic aromatic hydrocarbons in Singapore's atmosphere.

PubMed

Urbančok, Dejan; Payne, Anthony J R; Webster, Richard D

2017-10-01

A study of 16 United States Environmental Protection Agency (USEPA) priority listed PAHs associated with particulate matter ≤ 10 μm (PM 10 ) was conducted in Singapore during the period 29th May 2015 to 28th May 2016. The sampling period coincided with an extensive, regional smoke haze episode (5th September to 25th October) that occurred as a result of forest and peat fires in neighboring Indonesia. Throughout this study, 54 atmospheric PM 10 samples were collected in 24 h periods using a high volume sampler (HVS) and quarts fiber filters (QFF) as the collection medium. Hysplit software for computing 3-D backward air mass trajectories, diagnostic ratio analysis and ring number distribution calculations were used to examine the sources of PAHs in the atmosphere in Singapore. Under normal conditions the total PAH concentrations were in a range from 0.68 ng m -3 to 3.07 ng m -3 , while for the high haze period the results showed approximately double the concentrations with a maximum value of 5.97 ng m -3 . Diagnostic ratio (DR) and principal component analysis (PCA) were conducted and indicated the contribution of the traffic as a dominant pyrogenic source of PAHs during normal periods, while results from the haze dataset showed relatively strong influence of smoke from peat and forest fires in Indonesia. Environmental and health risk from PAHs were assessed for both regular and hazy days. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemical characterization and source apportionment of fine particulate matter in Yangzhou, China, using offline aerosol mass spectrometry

NASA Astrophysics Data System (ADS)

Li, L.; Ge, X.; Xu, J.; Ye, Z.

2016-12-01

In recent years, Aerodyne Aerosol Mass Spectrometer (AMS) has been widely used for online and real-time monitoring of fine aerosol particles all over the world. However, due to the high cost and complex maintenance, the AMS was typically deployed for short-term intense field measurements, limiting its ability in elucidating the long-term behaviors and dominant sources of regional fine particles (PM2.5). In this study, we collected daily PM2.5 filter samples across a relatively long period (November 2015 to April 2016, in total >100 samples) using a high-volume sampler, in urban Yangzhou - a city in the Yangtze River Delta region, China. These samples were analyzed by using a suite of analytical techniques, for the water-soluble inorganic ions (WSIs), organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC) and total nitrogen (TN), trace metal elements, etc. More importantly, an Aerodyne soot particle aerosol mass spectrometer (SP-AMS) was for the first time introduced for the offline characterization of the PM2.5 samples collected in this region. In particular, Positive matrix factorization was conducted on the SP-AMS determined water-soluble fraction of organic aerosols (WSOA), and three distinct sources were separated, including a primary OA (POA), a less oxygenated OA (LOOA), and a more oxygenated OA (MOOA). Chemical characteristics and evolution processes of these OA subcomponents were further discussed. Our results are useful for the air pollution management in the YRD region, and the technique developed can be applied elsewhere as well.

PM2.5-bound PAHs in three indoor and one outdoor air in Beijing: Concentration, source and health risk assessment.

PubMed

Chen, Ying; Li, Xinghua; Zhu, Tianle; Han, Yingjie; Lv, Dong

2017-05-15

Three indoor (residential home, dormitory, and office) and one outdoor concentrations of PM 2.5 -bound Polycyclic aromatic hydrocarbons (PAHs) were analyzed in Beijing across four seasons. The highest and lowest concentration of total PAHs for outdoor appeared in winter and in summer with averages of 200.1 and 9.1ng/m 3 respectively. The seasonal variations of total PAHs in three indoor sites were the same as outdoor. The correlation analysis between the indoor and outdoor samples showed that the annual mean I/O ratios of total PAHs in the three sites were lower than 1. Source apportionment showed vehicle exhaust, coal combustion, and biomass burning were the major contributors of indoor and outdoor PM 2.5 -bound PAHs. Indoor source, such as camphor pollution, was identified in the dormitory, while camphor pollution and cooking sources were identified in the residential home. The annual averages of Benzo[a]pyrene equivalent concentration (BaP eq ) were 7.6, 7.8, 7.7 and 12.7ng/m 3 for the dormitory, office, residential home and outdoor samples respectively, far higher than the annual limit of 1ng/m 3 regulated by European Commission. Life lung cancer risk (LLCR) in four sites across four seasons were over the acceptable cancer risk level, showing the cancer risk were at a high level in both indoor and outdoor sites in Beijing, and its level in indoor sites was much lower than in the outdoor site. The health risk assessment indicated the level of PAHs cancer risk on human for three indoor sites were similar. The results call for the development of more stringent control measures to reduce PAHs emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

Characteristics of lead isotope ratios and elemental concentrations in PM 10 fraction of airborne particulate matter in Shanghai after the phase-out of leaded gasoline

NASA Astrophysics Data System (ADS)

Zheng, Jian; Tan, Mingguang; Shibata, Yasuyuki; Tanaka, Atsushi; Li, Yan; Zhang, Guilin; Zhang, Yuanmao; Shan, Zuci

The stable lead (Pb) isotope ratios and the concentrations of 23 elements, including heavy metals and toxic elements, were measured in the PM 10 airborne particle samples collected at seven monitoring sites in Shanghai, China, to evaluate the current elemental compositions and local airborne Pb isotope ratio characteristics. Some source-related samples, such as cement, coal and oil combustion dust, metallurgic dust, vehicle exhaust particles derived from leaded gasoline and unleaded gasoline, and polluted soils were analyzed for their Pb content and isotope ratio and compared to those observed in PM 10 samples. Airborne Pb concentration ranged from 167 to 854 ng/m 3 in the seven monitored sites with an average of 515 ng/m 3 in Shanghai, indicating that a high concentration of Pb remains in the air after the phasing out of leaded gasoline. Lead isotopic compositions in airborne particles ( 207Pb/ 206Pb, 0.8608±0.0018; 208Pb/ 206Pb, 2.105±0.005) are clearly distinct from the vehicle exhaust particles ( 207Pb/ 206Pb, 0.8854±0.0075; 208Pb/ 206Pb, 2.145±0.006), suggesting that the automotive lead is not currently the major component of Pb in the air. By using a binary mixing equation, a source apportionment based on 207Pb/ 206Pb ratios, indicates that the contribution from automotive emission to the airborne Pb is around 20%. The Pb isotope ratios obtained in the source-related samples confirmed that the major emission sources are metallurgic dust, coal combustion, and cement.

Sources of atmospheric aerosol from long-term measurements (5 years) of chemical composition in Athens, Greece.

PubMed

Paraskevopoulou, D; Liakakou, E; Gerasopoulos, E; Mihalopoulos, N

2015-09-15

To identify the sources of aerosols in Greater Athens Area (GAA), a total of 1510 daily samples of fine (PM 2.5) and coarse (PM 10-2,5) aerosols were collected at a suburban site (Penteli), during a five year period (May 2008-April 2013) corresponding to the period before and during the financial crisis. In addition, aerosol sampling was also conducted in parallel at an urban site (Thissio), during specific, short-term campaigns during all seasons. In all these samples mass and chemical composition measurements were performed, the latest only at the fine fraction. Particulate organic matter (POM) and ionic masses (IM) are the main contributors of aerosol mass, equally contributing by accounting for about 24% of the fine aerosol mass. In the IM, nss-SO4(-2) is the prevailing specie followed by NO3(-) and NH4(+) and shows a decreasing trend during the 2008-2013 period similar to that observed for PM masses. The contribution of water in fine aerosol is equally significant (21 ± 2%), while during dust transport, the contribution of dust increases from 7 ± 2% to 31 ± 9%. Source apportionment (PCA and PMF) and mass closure exercises identified the presence of six sources of fine aerosols: secondary photochemistry, primary combustion, soil, biomass burning, sea salt and traffic. Finally, from winter 2012 to winter 2013 the contribution of POM to the urban aerosol mass is increased by almost 30%, reflecting the impact of wood combustion (dominant fuel for domestic heating) to air quality in Athens, which massively started in winter 2013. Copyright © 2015 Elsevier B.V. All rights reserved.

Is it time to tackle PM(2.5) air pollutions in China from biomass-burning emissions?

PubMed

Zhang, Yan-Lin; Cao, Fang

2015-07-01

An increase in haze days has been observed in China over the past two decades due to the rapid industrialization, urbanization and energy consumptions. To address this server issue, Chinese central government has recently released the Action Plan on Prevention and Control of Air Pollution, which mainly focuses on regulation of indusial and transport-related emissions with major energy consumption from fossil fuels. This comprehensive and toughest plan is definitely a major step in the right direction aiming at beautiful and environmental-friendly China; however, based on recent source apportionment results, we suggest that strengthening regulation emissions from biomass-burning sources in both urban and rural areas is needed to meet a rigorous reduction target. Here, household biofuel and open biomass burning are highlighted, as impacts of these emissions can cause local and regional pollution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Size distribution of particle-phase molecular markers during a severe winter pollution episode.

PubMed

Kleeman, Michael J; Riddle, Sarah G; Jakober, Chris A

2008-09-01

Airborne particulate matter was collected using filter samplers and cascade impactors in six size fractions below 1.8 microm during a severe winter air pollution event at three sites in the Central Valley of California. The smallest size fraction analyzed was 0.056 < Dp <0.1 microm particle diameter, which accounts for the majority of the mass in the ultrafine (PM0.1) size range. Separate samples were collected during the daytime (10 a.m. to 6 p.m. PST) and nighttime (8 p.m. to 8 a.m. PST) to characterize diurnal patterns. Each sample was extracted with organic solvents and analyzed using gas chromatography mass spectrometry for molecular markers that can be used for size-resolved source apportionment calculations. Colocated impactor and filter measurements were highly correlated (R8 > 0.8) for retene, benzo[ghi]flouranthene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[e]pyrene, benzo[a]pyrene, perylene, indeno[1,2,3-cd]pyrene, benzo[ghi]perylene, coronene, MW302 polycyclic aromatic hydrocarbon (PAHs), 17beta(H)-21alpha(H)-30-norhopane, 17alpha(H)-21beta(H)-hopane, alphabetabeta-20R-C29-ethylcholestane, levoglucosan, and cholesterol. Of these compounds, levoglucosan was present in the highest concentration (60-2080 ng m(-3)) followed by cholesterol (6-35 ng m(-3)), PAHs (2-38 ng m(-3)), and hopanes and steranes (0-2 ng m(-3)). Nighttime concentrations were higher than daytime concentrations in all cases. Organic compound size distributions were generally similar to the total carbon size distributions during the nighttime but showed greater variability during the daytime. This may reflect the dominance of fresh emission in the stagnant surface layer during the evening hours and the presence of aged organic aerosol at the surface during the daytime when the atmosphere is better mixed. All of the measured organic compound particle size distributions had a single mode that peaked somewhere between 0.18 and 0.56 microm, but the width of each distribution varied by compound. Cholesterol generally had the broadest particle size distribution, while benzo[ghi]perylene and 17alpha(H)-21beta(H)-29-norhopane generally had sharper peaks. The difference between the size distributions of the various particle-phase organic compounds reflects the fact that these compounds exist in particles emitted from different sources. The results of the current study will prove useful for size-resolved source apportionment exercises.

Chemical and optical properties of PM2.5 from on-road operation of light duty vehicles in Delhi city.

PubMed

Jaiprakash; Habib, Gazala

2017-05-15

This study reports emission factors of PM 2.5 , elemental carbon (EC), organic carbon (OC), ions, trace elements and mass absorption cross-sections (MAC) of aerosol emitted from the on-road operation of light duty vehicles of different vintages. A portable dilution system was used to achieve complete quenching of aerosol at near ambient condition. The particles were collected on the filters and analyzed for chemical and light absorbing properties of aerosol. The diesel-powered passenger cars emitted higher PM 2.5 (56-356mgkm -1 ) with a large fraction of EC (37-65%), while emissions from gasoline (46-78mgkm -1 ), and CNG vehicles (33-34mgkm -1 ) were low and contained low EC (5-15%) and remarkably high OC (46-91%). The MAC of aerosols for diesel vehicles (32-208m 2 g -1 of PM 2.5 ) were well explained by EC content (31-62%) and showed similarity with MAC values reported for wood fuel combustion in cooking stoves indicating the two sources cannot be resolved on the basis of light absorption properties in source apportionment studies. Ionic contributions to PM 2.5 were highest for 4W-gasoline (11-19%) compared to 4W-diesel (7-11%), and CNG (9-10%). The abundance of ions such as Na + , Ca 2+ , SO 4 2- , NO 3 - , and NH 4 + could be due to use of lubricant oil and abrasive nature of engine of old vehicles. Trace elements (Al, Fe, Zn, Pb, and Cu) emitted from after-treatment devices, additives in lube oil, and wearing of engine components, were found to be 2-14%, 3-8% and 11-12% of total PM 2.5 for 4W of diesel, gasoline, and CNG respectively. This study indicates that aerosol emissions from on-road vehicles show a strong dependency on vehicle maintenance, engine type and after-treatment techniques. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of the chemical composition of PM2.5 emitted from on-road China III and China IV diesel trucks in Beijing, China.

PubMed

Wu, Bobo; Shen, Xianbao; Cao, Xinyue; Yao, Zhiliang; Wu, Yunong

2016-05-01

The composition of diesel exhaust fine particulate matter (PM2.5) is of growing interest because of its impacts on health and climatic factors and its application in source apportionment and aerosol modeling. We characterized the detailed chemical composition of the PM2.5, including the organic carbon (OC), elemental carbon (EC), water-soluble ions (WSIs), and elemental contents, emitted from China III and China IV diesel trucks (nine each) based on real-world measurements in Beijing using a portable emissions measurement system (PEMS). Carbonaceous compounds were the dominant components (totaling approximately 87%) of the PM2.5, similar to the results (greater than 80% of the PM2.5) of our previous study of on-road China III diesel trucks. In general, the amounts of individual component groups (carbonaceous compounds, WSIs, and elements) and PM2.5 emissions for China IV diesel trucks were lower than those of China III diesel trucks of the same size, except for the WSIs and elements for the light- and medium-duty diesel trucks. The EC/OC mass ratios were strongly dependent on the emission standards, and the ratios of China IV diesel trucks were higher than those of China III diesel trucks of the same size. The chemical species in the PM2.5 were significantly affected by the driving conditions. Overall, the emission factors (EFs) of the PM2.5 and OC under non-highway (NHW) driving conditions were higher than those under highway (HW) driving conditions, and the EC/OC mass ratios presented an increasing trend, with decreasing OC/PM2.5 and increasing EC/PM2.5 from NHW to HW driving conditions; similar trends were reported in our previous study. In addition, Pearson's correlation coefficients among the PM2.5 species were analyzed to determine the relationships among the various chemical components. Copyright © 2016 Elsevier B.V. All rights reserved.

Chemical composition and sources of organic aerosols over London from the ClearfLo 2012 campaigns

NASA Astrophysics Data System (ADS)

Finessi, Emanuela; Holmes, Rachel; Hopkins, James; Lee, James; Harrison, Roy; Hamilton, Jacqueline

2014-05-01

Air quality in urban areas represents a major public health issue with around one third of the European population concentrated in cities and numbers expected to increase at global scale, particularly in developing countries. Particulate matter (PM) represents a primary threat for human health as numerous studies have confirmed the association between increased levels of cardiovascular and respiratory diseases with the exposure to PM. Despite considerable efforts made in improving air quality and progressively stricter emissions regulations, the PM concentrations have not changed much over the past decades for reasons that remain unclear, and highlight that studies on PM source apportionment are required for the formulation of effective policy. We investigated the chemical composition of organic aerosol (OA) collected during two intensive field campaigns held in winter and summer 2012 in the frame of the project Clean air for London (http://www.clearflo.ac.uk/). PM samples were collected both at a city background site (North Kensington) and at a rural site 50 km southeast of London (Detling) with 8 to 24 hours sampling schedule and analysed using off-line methods. Thermal-optical analysis was used to quantify OC-EC components while a suite of soft ionization mass spectrometric techniques was deployed for detailed chemical characterization. Liquid chromatography mass Spectrometry (LC-MSn) was mostly used for the simultaneous detection and quantification of various tracers for both primary and secondary OA sources. Well-established markers for wood burning primary OA like levoglucosan and azelaic acid were quantified together with various classes of nitroaromatics including methyl-nitrocatechols that are potential tracers for wood burning secondary OA. In addition, oxidation products of biogenic VOCs such as isoprene and monoterpenes were also quantified for both seasons and sites. A non-negligible contribution from biogenic SOA to urban OA was found in summertime measurements. It is hoped that these data will provide an insight into the sources and chemical processing of organic aerosol in London and help to evaluate the effects of this megacity on the surrounding areas.

Source apportionment of soil heavy metals using robust absolute principal component scores-robust geographically weighted regression (RAPCS-RGWR) receptor model.

PubMed

Qu, Mingkai; Wang, Yan; Huang, Biao; Zhao, Yongcun

2018-06-01

The traditional source apportionment models, such as absolute principal component scores-multiple linear regression (APCS-MLR), are usually susceptible to outliers, which may be widely present in the regional geochemical dataset. Furthermore, the models are merely built on variable space instead of geographical space and thus cannot effectively capture the local spatial characteristics of each source contributions. To overcome the limitations, a new receptor model, robust absolute principal component scores-robust geographically weighted regression (RAPCS-RGWR), was proposed based on the traditional APCS-MLR model. Then, the new method was applied to the source apportionment of soil metal elements in a region of Wuhan City, China as a case study. Evaluations revealed that: (i) RAPCS-RGWR model had better performance than APCS-MLR model in the identification of the major sources of soil metal elements, and (ii) source contributions estimated by RAPCS-RGWR model were more close to the true soil metal concentrations than that estimated by APCS-MLR model. It is shown that the proposed RAPCS-RGWR model is a more effective source apportionment method than APCS-MLR (i.e., non-robust and global model) in dealing with the regional geochemical dataset. Copyright © 2018 Elsevier B.V. All rights reserved.

Control of Toxic Chemicals in Puget Sound, Phase 3: Study Of Atmospheric Deposition of Air Toxics to the Surface of Puget Sound

DTIC Science & Technology

2007-01-01

deposition directly to Puget Sound was an important source of PAHs, polybrominated diphenyl ethers (PBDEs), and heavy metals . In most cases, atmospheric...versus Atmospheric Fluxes ........................................................................66  PAH Source Apportionment ...temperature inversions) on air quality during the wet season. A semi-quantitative apportionment study permitted a first-order characterization of source

Microbial Biomarkers for Native and Agricultural Soil Inputs to Atmospheric Particulate Matter

NASA Astrophysics Data System (ADS)

Fulton, J. M.; Herckes, P.; Fraser, M. P.; Collins, J.; Van Mooy, B. A.

2017-12-01

Intense dust storms (haboobs) erode desert soils and cause dramatic short-term increases in particulate matter (PM) concentration in the atmosphere. Background atmospheric PM levels in the southwestern United States also commonly exceed the National Ambient Air Quality Standards, so episodic haboobs and normal weather patterns both contribute to aeolian transport. We analyzed fine (PM2.5) and coarse (PM>2.5) dust fractions sampled in Tempe, Arizona for molecular biomarkers indicative of dust sourced from either native or agricultural soils. We focused on pigments and intact polar lipids (IPLs) that were also in soil crusts collected in the region. The PM samples were taken during two weeks (23 July to 5 August 2014) that included two haboobs during the first week and mostly calm weather with minor rainfall during the second week. We detected scytonemin, a diagnostic pigment biomarker for cyanobacteria, in all PM>2.5 samples, but its concentration was highest in haboob dust. Similarly, scytonemin was only abundant in PM2.5 samples taken during haboobs. Scytonemin is an important component of native biological soil crusts, protecting the crust community from UV radiation, and is ca. two orders of magnitude less abundant in disturbed agricultural soils. In biological soil crusts, scytonemin is associated with extracellular polysaccharides that are produced by cyanobacteria and bind soil into cohesive crusts. The association between scytonemin and haboobs suggests that native soil erosion is facilitated by high energy, episodic events that overcome crust cohesion. IPLs were abundant in agricultural soil crusts and included phosphatidylethanolamine from soil bacteria and a glucosylceramide from fungi. These compounds had similar concentration in haboob and background dust, suggesting agricultural or otherwise disturbed soils contribute more to ambient dust. In this study, we employed a new high resolution mass spectrometric method that produces molecular formulas and structural information, even at very low abundance. Employing this analysis on atmospheric PM improves our understanding of mechanisms by which soil crust biomarkers are transferred to lake and ocean sediments and can also contribute to source apportionment models for describing atmospheric dust contamination.

Sources of the PM10 aerosol in Flanders, Belgium, and re-assessment of the contribution from wood burning.

PubMed

Maenhaut, Willy; Vermeylen, Reinhilde; Claeys, Magda; Vercauteren, Jordy; Roekens, Edward

2016-08-15

From 30 June 2011 to 2 July 2012 PM10 aerosol samples were simultaneously taken every 4th day at four urban background sites in Flanders, Belgium. The sites were in Antwerpen, Gent, Brugge, and Oostende. The PM10 mass concentration was determined by weighing; organic and elemental carbon (OC and EC) were measured by thermal-optical analysis, the wood burning tracers levoglucosan, mannosan and galactosan were determined by gas chromatography/mass spectrometry, 8 water-soluble ions were measured by ion chromatography, and 15 elements were determined by a combination of inductively coupled plasma atomic emission spectrometry and mass spectrometry. The multi-species dataset was subjected to receptor modeling by PMF. The 10 retained factors (with their overall average percentage contributions to the experimental PM10 mass) were wood burning (9.5%), secondary nitrate (24%), secondary sulfate (12.6%), sea salt (10.0%), aged sea salt (19.2%), crustal matter (9.7%), non-ferrous metals (1.81%), traffic (10.3%), non-exhaust traffic (0.52%), and heavy oil burning (3.0%). The average contributions of wood smoke for the four sites were quite substantial in winter and ranged from 12.5 to 20% for the PM10 mass and from 47 to 64% for PM10 OC. Wood burning appeared to be also a notable source of As, Cd, and Pb. The contribution from wood burning to the PM10 mass and OC was also assessed by making use of levoglucosan as single marker compound and the conversion factors of Schmidl et al. (2008), as done in our previous study on wood burning in Flanders (Maenhaut et al., 2012). However, the apportionments were much lower than those deduced from PMF. It seems that the conversion factors of Schmidl et al. (2008) may not be applicable to wood burning in Flanders. From scatter plots of the PMF-derived wood smoke OC and PM versus levoglucosan, we arrived at conversion factors of 9.7 and 22.6, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

High time-resolved chemical compositions, sources and evolution for atmospheric submicron aerosols in the winter of Beijing

NASA Astrophysics Data System (ADS)

Min, H.; Hu, W.; Zheng, J.; Guo, S.; Wu, Y.; Zeng, L.; Lu, S.; Xie, S.; Zhang, Y.

2017-12-01

Severe regional haze problem in the megacity Beijing and surrounding areas has attracted much attention in recent years. In order to investigate the secondary formation and aging process of urban aerosols, intensive campaigns were conducted in the winter of 2010 and 2013 at an urban site in Beijing. An Aerodyne high resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS) was deployed to measure chemical components of PM1, coupled with multiple state of the art online instruments. In the winter of 2010, PM1 mass concentrations changed dramatically along with meteorological conditions. The high average fraction (58%) of primary species in PM1 indicated that primary emissions usually played a more important role. Based on the source apportionment results, 45% POA are from non-fossil sources, contributed by cooking OA and biomass burning OA (BBOA). Cooking OA, accounting for 13-24% of OA, is an important non-fossil carbon source in all years of Beijing and should not be neglected. The fossil sources of POA include hydrocarbon-like OA from vehicle emissions and coal combustion OA (CCOA). The CCOA and BBOA were the two main contributors (57% of OA) for the highest OA concentrations (>100 μg m-3). In the winter of 2013, OOA (MO-OOA and LO-OOA), accounted for 50% of PM1, while (OOA+SNA) contributed 60-80%, suggesting that secondary formation played an important role in the PM pollution. In the winter of 2010 higher OOA/Ox (= NO2 + O3) ratio (0.49 μg m-3 ppb-1) than these ratios from western cities (0.03-0.16 μg m-3 ppb-1) was observed, which may be due to the aqueous reaction or extra SOA formation contributed by semi-VOCs from various primary sources (e.g., BBOA or CCOA). However, aqueous chemistry resulting in efficient secondary formation during occasional periods with high relative humidity may also contribute substantially to haze in winter. CCOA was only identified in winter due to domestic heating. These results signified that the comprehensive management for biomass burning and coal combustion emissions is needed. Further strengthening the regional emission control of primary particulate and precursors of secondary species is expected.

PM2.5 source apportionment with organic markers in the Southeastern Aerosol Research and Characterization (SEARCH) study.

PubMed

Watson, John G; Chow, Judith C; Lowenthal, Douglas H; Antony Chen, L-W; Shaw, Stephanie; Edgerton, Eric S; Blanchard, Charles L

2015-09-01

Positive matrix factorization (PMF) and effective variance (EV) solutions to the chemical mass balance (CMB) were applied to PM(2.5) (particulate matter with an aerodynamic diameter <2.5 μm) mass and chemically speciated measurements for samples taken from 2008 to 2010 at the Atlanta, Georgia, and Birmingham, Alabama, sites. Commonly measured PM(2.5) mass, elemental, ionic, and thermal carbon fraction concentrations were supplemented with detailed nonpolar organic speciation by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). Source contribution estimates were calculated for motor vehicle exhaust, biomass burning, cooking, coal-fired power plants, road dust, vegetative detritus, and secondary sulfates and nitrates for Atlanta. Similar sources were found for Birmingham, with the addition of an industrial source and the separation of biomass burning into open burning and residential wood combustion. EV-CMB results based on conventional species were qualitatively similar to those estimated by PMF-CMB. Secondary ammonium sulfate was the largest contributor, accounting for 27-38% of PM(2.5), followed by biomass burning (21-24%) and motor vehicle exhaust (9-24%) at both sites, with 4-6% of PM(2.5) attributed to coal-fired power plants by EV-CMB. Including organic compounds in the EV-CMB reduced the motor vehicle exhaust and biomass burning contributions at both sites, with a 13-23% deficit for PM(2.5) mass. The PMF-CMB solution showed mixing of sources within the derived factors, both with and without the addition of speciated organics, as is often the case with complex source mixtures such as those at these urban-scale sites. The nonpolar TD-GC/MS compounds can be obtained from existing filter samples and are a useful complement to the elements, ions, and carbon fractions. However, they should be supplemented with other methods, such as TD-GC/MS on derivitized samples, to obtain a wider range of polar compounds such as sterols, sugars, and organic acids. The PMF and EV solutions to the CMB equations are complementary to, rather than replacements for, each other, as comparisons of their results reveal uncertainties that are not otherwise evident. Organic markers can be measured on currently acquired PM(2.5) filter samples by thermal methods. These markers can complement element, ion, and carbon fraction measurements from long-term speciation networks. Applying the positive matrix factorization and effective variance solutions for the chemical mass balance equations provides useful information on the accuracy of the source contribution estimates. Nonpolar compounds need to be complemented with polar compounds to better apportion cooking and secondary organic aerosol contributors.

A review of current knowledge concerning PM2. 5 chemical composition, aerosol optical properties and their relationships across China

NASA Astrophysics Data System (ADS)

Tao, Jun; Zhang, Leiming; Cao, Junji; Zhang, Renjian

2017-08-01

To obtain a thorough knowledge of PM2. 5 chemical composition and its impact on aerosol optical properties across China, existing field studies conducted after the year 2000 are reviewed and summarized in terms of geographical, interannual and seasonal distributions. Annual PM2. 5 was up to 6 times the National Ambient Air Quality Standards (NAAQS) in some megacities in northern China. Annual PM2. 5 was higher in northern than southern cities, and higher in inland than coastal cities. In a few cities with data longer than a decade, PM2. 5 showed a slight decrease only in the second half of the past decade, while carbonaceous aerosols decreased, sulfate (SO42-) and ammonium (NH4+) remained at high levels, and nitrate (NO3-) increased. The highest seasonal averages of PM2. 5 and its major chemical components were typically observed in the cold seasons. Annual average contributions of secondary inorganic aerosols to PM2. 5 ranged from 25 to 48 %, and those of carbonaceous aerosols ranged from 23 to 47 %, both with higher contributions in southern regions due to the frequent dust events in northern China. Source apportionment analysis identified secondary inorganic aerosols, coal combustion and traffic emission as the top three source factors contributing to PM2. 5 mass in most Chinese cities, and the sum of these three source factors explained 44 to 82 % of PM2. 5 mass on annual average across China. Biomass emission in most cities, industrial emission in industrial cities, dust emission in northern cities and ship emission in coastal cities are other major source factors, each of which contributed 7-27 % to PM2. 5 mass in applicable cities. The geographical pattern of scattering coefficient (bsp) was similar to that of PM2. 5, and that of aerosol absorption coefficient (bap) was determined by elemental carbon (EC) mass concentration and its coating. bsp in ambient condition of relative humidity (RH) = 80 % can be amplified by about 1.8 times that under dry conditions. Secondary inorganic aerosols accounted for about 60 % of aerosol extinction coefficient (bext) at RH greater than 70 %. The mass scattering efficiency (MSE) of PM2. 5 ranged from 3.0 to 5.0 m2 g-1 for aerosols produced from anthropogenic emissions and from 0.7 to 1.0 m2 g-1 for natural dust aerosols. The mass absorption efficiency (MAE) of EC ranged from 6.5 to 12.4 m2 g-1 in urban environments, but the MAE of water-soluble organic carbon was only 0.05 to 0.11 m2 g-1. Historical emission control policies in China and their effectiveness were discussed based on available chemically resolved PM2. 5 data, which provides the much needed knowledge for guiding future studies and emissions policies.

Source apportionment to PM10 and PM2.5 at multiple sites in the Bay of Gibraltar (S Spain) by PMF: estimate of shipping emission

NASA Astrophysics Data System (ADS)

Pandolfi, M.; Gonzalez-Castanedo, Y.; Alastuey, A.; Pey, J.; Querol, X.; de La Rosa, J. D.

2009-04-01

The recognized adverse health effect of the PM10 and PM2.5 particles leads to an increasing demand of a more efficient control of pollutant emissions especially in industrial and/or urban sites. The degree with which the control of the emissions can be accomplished depends on the identification of the pollutant sources and the estimation of their contribution. The chemical speciation of ambient PM coupled with receptor modelling can be considered as a powerful tool to estimate origin of the sources and their contribution to the PM10 and PM2.5 fractions. This work aims to evaluate the effect on air quality of the anthropogenic activities performed in one of the most important industrial estates of Southern Spain located in the Bay of Gibraltar. The area under study is characterized by the presence of metallurgy industries and oil refineries around which four urban agglomerates are located, namely: Los Barrios (36°11'7.39"N, 5°29'33.89"O), La Linea (36° 9'40.24"N, 5°20'53.72"O), Algeciras (36°7'47.21"N, 5°26'51.71"O) y Puente Mayorga (36°10'54.60"N, 5°23'8.32"O). Traffic is consequently another important source of pollutants in the considered area together with an intense shipping activity. The estimation of the pollutant sources and their contribution was obtained by applying the Positive Matrix Factorization (PMF) model to the PM10 and PM2.5 levels and chemical speciation data simultaneously obtained in the four urban agglomerates during a period of 4 years (March 2003 - December 2007). Given the small size of the area under study, the PM data collected in all the four stations was simultaneously introduced within the PMF model. This procedure allowed the PMF to use a higher number of data rather than using the 4 database separately, thus improving the performances of the model. Following this procedure a total of 567 and 341 samples for the PM10 and PM2.5 fractions respectively were introduced within the PMF. Moreover, before running the model, a detailed inspection of the database was performed in order to look for the possible presence of weaker data such as contaminated data, below detection limit data, missing data etc. This procedure is important in order to improve the performances of the model, reducing the error associated with the calculated sources contributions. In the present work seven sources were obtained in both PM10 and PM2.5 fractions, namely: crustal (traced by Al, Ca, K, Ti, Fe, Rb, Sr), marine (traced by Na, Cl, Mg), industrial (Cr, Mn, P, Zn, Fe, As, Ni, Pb), oil combustion (traced by V, Ni y La from both oil refinery and shipping emissions), traffic (OC+EC, Cu, Sn, Sb), secondary sulphate (SO4= and NH4+), ammonium nitrate in PM2.5 (traced by NO3- and NH4+) and sodium nitrate in PM10 (Na and NO3-). In PM10 fraction the main contributing sources in all stations were secondary sulphate (19-22% of PM10 mass), sodium nitrate (15-21%) and crustal (14-23%) followed by traffic (10-21%), marine (10-17%), oil combustion (6-9%) and industrial (1-5%). The main contributing sources in PM2.5 were regional sulphate (28-34%), ammonium nitrate and traffic (10-15%), crustal (8-18%), oil combustion and marine (8-10%), and industrial (2-7%). Further information on source contributions and locations were obtained by coupling PMF with wind direction data which show two privileged mean wind directions in the considered area: SSE-ESE (75% of occurrence) and W-NW (80% of occurrence). In this work wind data was used to separately evaluate the contributions from shipping and oil refinery which were not separated by the PMF model mainly as a consequence of the similarity in the fingerprints of these two sources. Acknowledgements This work was funded by the Spanish Ministry of Science and Innovation (GRACCIE-SCD2007-00067), Ministry of the Environment (CALIOPE, Ref.: 441-2006-3-12.1), and the Junta of Andalucía.

Source apportionment of exposures to volatile organic compounds. I. Evaluation of receptor models using simulated exposure data

NASA Astrophysics Data System (ADS)

Miller, Shelly L.; Anderson, Melissa J.; Daly, Eileen P.; Milford, Jana B.

Four receptor-oriented source apportionment models were evaluated by applying them to simulated personal exposure data for select volatile organic compounds (VOCs) that were generated by Monte Carlo sampling from known source contributions and profiles. The exposure sources modeled are environmental tobacco smoke, paint emissions, cleaning and/or pesticide products, gasoline vapors, automobile exhaust, and wastewater treatment plant emissions. The receptor models analyzed are chemical mass balance, principal component analysis/absolute principal component scores, positive matrix factorization (PMF), and graphical ratio analysis for composition estimates/source apportionment by factors with explicit restriction, incorporated in the UNMIX model. All models identified only the major contributors to total exposure concentrations. PMF extracted factor profiles that most closely represented the major sources used to generate the simulated data. None of the models were able to distinguish between sources with similar chemical profiles. Sources that contributed <5% to the average total VOC exposure were not identified.

Problems in the fingerprints based polycyclic aromatic hydrocarbons source apportionment analysis and a practical solution.

PubMed

Zou, Yonghong; Wang, Lixia; Christensen, Erik R

2015-10-01

This work intended to explain the challenges of the fingerprints based source apportionment method for polycyclic aromatic hydrocarbons (PAH) in the aquatic environment, and to illustrate a practical and robust solution. The PAH data detected in the sediment cores from the Illinois River provide the basis of this study. Principal component analysis (PCA) separates PAH compounds into two groups reflecting their possible airborne transport patterns; but it is not able to suggest specific sources. Not all positive matrix factorization (PMF) determined sources are distinguishable due to the variability of source fingerprints. However, they constitute useful suggestions for inputs for a Bayesian chemical mass balance (CMB) analysis. The Bayesian CMB analysis takes into account the measurement errors as well as the variations of source fingerprints, and provides a credible source apportionment. Major PAH sources for Illinois River sediments are traffic (35%), coke oven (24%), coal combustion (18%), and wood combustion (14%). Copyright © 2015. Published by Elsevier Ltd.

Characterization of the wintertime particulate (PM1) pollution at an urban background site of Nicosia, Cyprus

NASA Astrophysics Data System (ADS)

Sciare, Jean; Kleanthous, Savvas; Pikridas, Michael; Vrekoussis, Mihalis; Oikonomou, Konstantina; Merabet, Hamza; Mihalopoulos, Nikos; Yassaa, Noureddine

2015-04-01

A 1-month intensive campaign was performed during December 2014 at Nicosia, Cyprus, a city of 240,000 inhabitants, representative of E. Mediterranean medium sized cities. This is the first of a series of intensive campaigns, part of the MISTRALS-ENVI-Med "CyAr" project (Cyprus Aerosols and gas precursors) and MISTRALS-ChArMEx program (Chemistry-Aerosol Mediterranean Experiment, http://charmex.lsce.ipsl.fr/), and , with the objective to distinguish between local and transported sources responsible for wintertime particulate pollution. The mass and composition of the major chemical constituents of submicron aerosols (PM1) was monitored at an urban background station located at the city's suburbs with a suite of real-time analyzers (TEOM 1400, OPC Grimm 1.108, Q-ACSM, Aethalometer AE31). Quality control of Q-ACSM and Aethalometer datasets was performed through closure studies (using co-located TEOM / OPC Grimm). The consistency of the dataset was further validated using the integrated (off-line) and real-time measurements performed by the local air quality network at other locations in the same city. Very high levels of Black Carbon and organics were systematically observed every night, typically maximizing at 22:00 local time, pointing to local combustion sources most probably related to domestic heating. Similar pattern has been observed in other cities in the Eastern Mediterranean (Pikridas et al., 2013) and partly has been attributed to the economic crisis (Vrekoussis et al., 2013). Source apportionment of organic aerosols (OA) was performed using the SourceFinder software (SoFi, http://www.psi.ch/acsm-stations/me-2) allowing the distinction between various primary/secondary OA sources that allowed us to better characterize the combustion sources responsible for the observed elevated nighttime PM1 levels. Acknowledgements: This campaign has been funded by MISTRALS (ENVI-Med CyAr & ChArMEx), CNRS-INSU, CEA, CyI, DLI, CDER and ECPL.

Source apportionment studies on particulate matter in Beijing/China

NASA Astrophysics Data System (ADS)

Suppan, P.; Shen, R.; Shao, L.; Schrader, S.; Schäfer, K.; Norra, S.; Vogel, B.; Cen, K.; Wang, Y.

2013-05-01

More than 15 million people in the greater area of Beijing are still suffering from severe air pollution levels caused by sources within the city itself but also from external impacts like severe dust storms and long range advection from the southern and central part of China. Within this context particulate matter (PM) is the major air pollutant in the greater area of Beijing (Garland et al., 2009). PM did not serve only as lead substance for air quality levels and therefore for adverse health impact effects but also for a strong influence on the climate system by changing e.g. the radiative balance. Investigations on emission reductions during the Olympic Summer Games in 2008 have caused a strong reduction on coarser particles (PM10) but not on smaller particles (PM2.5). In order to discriminate the composition of the particulate matter levels, the different behavior of coarser and smaller particles investigations on source attribution, particle characteristics and external impacts on the PM levels of the city of Beijing by measurements and modeling are performed: a) Examples of long term measurements of PM2.5 filter sampling in 2010/2011 with the objectives of detailed chemical (source attribution, carbon fraction, organic speciation and inorganic composition) and isotopic analyses as well as toxicological assessment in cooperation with several institutions (Karlsruhe Institute of Technology (IfGG/IMG), Helmholtz Zentrum München (HMGU), University Rostock (UR), Chinese University of Mining and Technology Beijing, CUMTB) will be discussed. b) The impact of dust storm events on the overall pollution level of particulate matter in the greater area of Beijing is being assessed by the online coupled comprehensive model system COSMO-ART. First results of the dust storm modeling in northern China (2011, April 30th) demonstrates very well the general behavior of the meteorological parameters temperature and humidity as well as a good agreement between modeled and measured dust storm concentration variability at Beijing in the course of time. The results show the importance of intertwine investigations of measurements and modeling, the analysis of local air pollution levels as well as the impact and analysis of advective processes in the greater region of Beijing. Comprehensive investigations on particulate matter are a prerequisite for the knowledge of the source strengths and source attribution to the overall air pollution level. Only this knowledge can help to formulate and to introduce specific reduction measures to reduce coarser as well as finer particulates.

Composition and source apportionment of PM1 at urban site Kanpur in India using PMF coupled with CBPF

NASA Astrophysics Data System (ADS)

Rai, Pragati; Chakraborty, Abhishek; Mandariya, Anil Kumar; Gupta, Tarun

2016-09-01

This study addresses the three major questions: (1) what are the emission sources of PM1 which are affecting the study area; (2) where do these emission sources come from; and (3) is there any temporal variation in the emission sources. To address these issues, two advanced statistical methods are described in this paper. Identification of emission sources was performed by EPA PMF (v 5.0) and to understand the temporal variability, sampling was done for three winter seasons 2008-09, 2009-10 and 2011-12 within Kanpur city. To identify the possible source directions, Conditional Bivariate Probability function (CBPF) was used. The average PM1 concentration was higher in 2008-09 followed by 2011-12 and 2009-10 winter seasons. 2008-09 winter showed sources such as secondary sources mixed with power plant emission (42.8%), industrial emission (32.3%), coal combustion, brick kilns and vehicular emission (13.2%) and residual oil combustion and road dust (11.7%). The major contributors during winter season 2009-10 were secondary sources (33.1%), biomass burning (23.3%), heavy oil combustion (13%), vehicular emission mixed with crustal dust (11.3%), leather tanning industries (10.3%), industrial emission (4%), coal combustion and brick kilns (3.4%) and solid waste burning and incineration (1.5%) compared to secondary sources mixed with biomass burning (42.3%), industrial emission and crustal dust (35.1%) and vehicular emission and brick kilns (22.6%) during 2011-12 winter season. PMF model revealed that secondary sources were the main contributors for all the three winter seasons followed by biomass burning and power plant emission. The results of CBPF analysis agreed well with the locations of known local point sources., e.g. in the case of industrial emissions, the maximum probability was in the direction between NES direction where almost all the major industries are located in and around Kanpur while in the opposite direction the probability of biomass burning was high due to a rural area in NWS direction.

ATMOSPHERIC AEROSOL SOURCE-RECEPTOR RELATIONSHIPS: THE ROLE OF COAL-FIRED POWER PLANTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen L. Robinson; Spyros N. Pandis; Cliff I. Davidson

2004-12-01

This report describes the technical progress made on the Pittsburgh Air Quality Study (PAQS) during the period of March 2004 through August 2004. Significant progress was made this project period on the analysis of ambient data, source apportionment, and deterministic modeling activities. Results highlighted in this report include evaluation of the performance of PMCAMx+ for an air pollution episode in the Eastern US, an emission profile for a coke production facility, ultrafine particle composition during a nucleation event, and a new hybrid approach for source apportionment. An agreement was reached with a utility to characterize fine particle and mercury emissionsmore » from a commercial coal fired power. Research in the next project period will include source testing of a coal fired power plant, source apportionment analysis, emission scenario modeling with PMCAMx+, and writing up results for submission as journal articles.« less

Origin of polycyclic aromatic hydrocarbons and other organic pollutants in the air particles of subway stations in Barcelona.

PubMed

van Drooge, Barend L; Prats, Raimon M; Reche, Cristina; Minguillón, MariCruz; Querol, Xavier; Grimalt, Joan O; Moreno, Teresa

2018-06-09

Underground subways transport large numbers of citizens in big cities, which must breathe air with limited ventilation. These atmospheric conditions may enhance the concentration of air pollutants from both outdoor and indoor air. The influence of ventilation conditions and maintenance activities on the concentrations of air pollutants have been studied. Particulate matter with aerodynamic diameter smaller than 2.5 μm (PM 2.5 ) in indoor air was sampled in ten platforms of nine subway stations of the metropolitan area of Barcelona in 2015 and 2016. These particles were analyzed for polycyclic aromatic hydrocarbons (PAH) and organic tracer compounds. The concentrations of PAH were in the range of the street air levels with higher PAH values in the colder period. No influence of nighttime maintenance activities was observed on the platform air quality during daytime. Source apportionment analysis using the concentrations of hopanes, nicotine and levoglucosan as molecular tracer compounds showed that 75% of the detected PAH at the platforms have an outdoor PM origin. The modern subway stations, with advanced ventilation and platform screen doors that separate the subway system from the platform, showed lowest PAH and PM concentrations. Copyright © 2018. Published by Elsevier B.V.

Apportionment of particulate matter sources in the Rio de Janeiro Metropolitan area

NASA Astrophysics Data System (ADS)

Gioda, A.; Mateus, V.; Ventura, L.; Amaral, B.

2013-05-01

Continuous monitoring of particulate matter (PM) is extremely important in order to observe possible trends and take measures to reduce emissions. In Brazil, few cities have network stations, which make these measurements even more crucial. Furthermore, there is a need to update and create new standards of air quality, which can only be done based on a suitable inventory. Levels of total suspended particles (TSP), PM10 and PM2.5 were monitored in the Metropolitan area of Rio de Janeiro. Mean concentrations of TSP, PM10 and PM2.5 were 70, 60 and 14 μg/m3, respectively. Some of the monitored sampling points exceeded the Brazilian guidelines for PM10 (50 μg/m3) and TSP (80 μg/m3). However, the PM2.5 levels measured in the present study are of extreme concern, since they exceeded the guideline suggested by the World Health Organization (WHO - 10 μg/m3) in almost all the study sites. The average PM2.5/PM10 ratios ranged from 0.1 to 0.3, being more dependent on traffic emissions, while PM10/PTS ratios ranged from 0.6 to 0.7. The particles were composed mainly of soil elements (~50%) and ammonium sulfate and ammonium nitrate (20-40%), which are recognized as secondary inorganic aerosols. Rural areas and sites near the ocean presented the lowest levels for all particle sizes. This is probably due to an enhanced dispersion of the particles by the sea breeze. On the other hand, higher PM concentrations were observed for the sites near industrial areas and heavy traffic, as expected. The monthly distribution profile observed for PM showed clear increases in PM levels from May to September at all stations. This increase is due to the stagnation of the air during winter, which is related to meteorological processes such as low relative humidity and low rainfall. Consequently, due to this stagnation pollutant concentrations show increases. According to the dataset from the Unified Health System there is a clear trend of increased hospitalizations for respiratory diseases in winter, when increased concentrations of PM are observed, which was verified in this study.

Aerosol Measurements in the Mid-Atlantic: Trends and Uncertainty

NASA Astrophysics Data System (ADS)

Hains, J. C.; Chen, L. A.; Taubman, B. F.; Dickerson, R. R.

2006-05-01

Elevated levels of PM2.5 are associated with cardiovascular and respiratory problems and even increased mortality rates. In 2002 we ran two commonly used PM2.5 speciation samplers (an IMPROVE sampler and an EPA sampler) in parallel at Fort Meade, Maryland (a suburban site located in the Baltimore- Washington urban corridor). The filters were analyzed at different labs. This experiment allowed us to calculate the 'real world' uncertainties associated with these instruments. The EPA method retrieved a January average PM2.5 mass of 9.3 μg/m3 with a standard deviation of 2.8 μg/m3, while the IMPROVE method retrieved an average mass of 7.3 μg/m3 with a standard deviation of 2.1 μg/m3. The EPA method retrieved a July average PM2.5 mass of 26.4 μg/m3 with a standard deviation of 14.6 μg/m3, while the IMPROVE method retrieved an average mass of 23.3 μg/m3 with a standard deviation of 13.0 μg/m3. We calculated a 5% uncertainty associated with the EPA and IMPROVE methods that accounts for uncertainties in flow control strategies and laboratory analysis. The RMS difference between the two methods in January was 2.1 μg/m3, which is about 25% of the monthly average mass and greater than the uncertainty we calculated. In July the RMS difference between the two methods was 5.2 μg/m3, about 20% of the monthly average mass, and greater than the uncertainty we calculated. The EPA methods retrieve consistently higher concentrations of PM2.5 than the IMPROVE methods on a daily basis in January and July. This suggests a systematic bias possibly resulting from contamination of either of the sampling methods. We reconstructed the mass and found that both samplers have good correlation between reconstructed and gravimetric mass, though the IMPROVE method has slightly better correlation than the EPA method. In January, organic carbon is the largest contributor to PM2.5 mass, and in July both sulfate and organic matter contribute substantially to PM2.5. Source apportionment models suggest that regional and local power plants are the major sources of sulfate, while mobile and vegetative burning factors are the major sources of organic carbon.

An integrated system for the determination of the local, regional and long-transport contributions to Particulate Matter concentrations

NASA Astrophysics Data System (ADS)

Amodio, M.; Andriani, E.; Daresta, B. E.; de Gennaro, G.; di Gilio, A.; Ielpo, P.,; Placentino, C. M.; Trizio, L.; Tutino, M.

2010-05-01

Several epidemiological studies have shown the negative effects of air pollution on human health, which range from respiratory and cardiovascular disease to neurotoxic effects, and cancer. Most recent investigations have been focused on health toxicological features of Particulate Matter (PM) and its interactions with other pollutants: it was found that fine particles (PM2.5) could be an effective media to transport these pollutants deeply into the lung and to cause many kind of reactions which include oxidative stress, local pulmonary and systemic inflammatory responses (Künzli and Perez, 2009). Based on these implications on public health, many countries have developed plans to suggest effective control strategies which involve the identification of Particulate Matter sources, the quantitative estimation of the emission rates of the pollutants, the understanding of PM transport, mixing and transformation processes and the identification of main factors influencing PM concentrations. In this field, receptor models can be useful tools to estimate sources contributions to PM collected in an area under investigations. Different approaches to receptor model analysis can be distinguished on basis of whether chemical characteristics of emission sources are required to be known before the source apportionment. The multivariate approach could be preferred when a lack of information concerning sources profiles occurred (Hopke, 2003). In this work, the results obtained by applying an integrated approach in the monitoring of PM using several typologies of instrumentations will be shown. A prototype for the determination of the contributions of a single source (‘fugitive emission') on the fine PM concentrations has been developed: it consists of a Swam dual-channel sampler, an OPC Monitor, a sonic anemometer and a PBL Mixing monitor. The investigated site chosen for the application of prototype will be the iron and steel pole of Taranto (Apulia Region, South of Italy). Fugitive emission campaign will be performed by using three different positions around the Taranto industrial area; the main interest on Taranto is due to the presence of several activities of high impact as very wide industrial area close to the town and the numerous maritime and military activities in the harbour area (Amodio et al., 2008). The aim is to triangulate the area of the examined source on the basis of the prevalent directions of the wind. The investigation will be completed by chemical-physical characterization of PM2.5 and PM10 samples collected by the prototype in order to have additional information about the possible emissive sources. The statistical analysis, performed by Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF), will be used for a detailed study of the impact of the local emissive source on the neighboring areas. Finally, the prototype will allow to identify and distinguish long range transport, regional and other local contributions on the fine PM concentrations. This work was supported by the Strategic Project PS_122 founded by Apulia Region. References Künzli, N., Perez, L., 2009. Swiss Medical Weekly 139(17-18), 242-250. Hopke, P.K., 2003. Journal of Chemometrics 17(5), 255-265. Amodio, M., Caselli, M., Daresta, B.E., de Gennaro, G., Ielpo, P., Placentino, C.M., Tutino, 2008. Chemical Engineering Transactions 16, 193-199.

Comprehensive chemical characterization of industrial PM2.5 from steel industry activities

NASA Astrophysics Data System (ADS)

Sylvestre, Alexandre; Mizzi, Aurélie; Mathiot, Sébastien; Masson, Fanny; Jaffrezo, Jean L.; Dron, Julien; Mesbah, Boualem; Wortham, Henri; Marchand, Nicolas

2017-03-01

Industrial sources are among the least documented PM (Particulate Matter) source in terms of chemical composition, which limits our understanding of their effective impact on ambient PM concentrations. We report 4 chemical emission profiles of PM2.5 for multiple activities located in a vast metallurgical complex. Emissions profiles were calculated as the difference of species concentrations between an upwind and a downwind site normalized by the absolute PM2.5 enrichment between both sites. We characterized the PM2.5 emissions profiles of the industrial activities related to the cast iron (complex 1) and the iron ore conversion processes (complex 2), as well as 2 storage areas: a blast furnace slag area (complex 3) and an ore terminal (complex 4). PM2.5 major fractions (Organic Carbon (OC) and Elemental Carbon (EC), major ions), organic markers as well as metals/trace elements are reported for the 4 industrial complexes. Among the trace elements, iron is the most emitted for the complex 1 (146.0 mg g-1 of PM2.5), the complex 2 (70.07 mg g-1) and the complex 3 (124.4 mg g-1) followed by Al, Mn and Zn. A strong emission of Polycyclic Aromatic Hydrocarbons (PAH), representing 1.3% of the Organic Matter (OM), is observed for the iron ore transformation complex (complex 2) which merges the activities of coke and iron sinter production and the blast furnace processes. In addition to unsubstituted PAHs, sulfur containing PAHs (SPAHs) are also significantly emitted (between 0.011 and 0.068 mg g-1) by the complex 2 and could become very useful organic markers of steel industry activities. For the complexes 1 and 2 (cast iron and iron ore converters), a strong fraction of sulfate ranging from 0.284 to 0.336 g g-1) and only partially neutralized by ammonium, is observed indicating that sulfates, if not directly emitted by the industrial activity, are formed very quickly in the plume. Emission from complex 4 (Ore terminal) are characterized by high contribution of Al (125.7 mg g-1 of PM2.5) but also, in a lesser extent, of Fe, Mn, Ti and Zn. We also highlighted high contribution of calcium ranging from 0.123 to 0.558 g g-1 for all of the industrial complexes under study. Since calcium is also widely used as a proxy of the dust contributions in source apportionment studies, our results suggest that this assumption should be reexamined in environments impacted by industrial emissions.

Organic speciation of size-segregated atmospheric particulate matter

NASA Astrophysics Data System (ADS)

Tremblay, Raphael

Particle size and composition are key factors controlling the impacts of particulate matter (PM) on human health and the environment. A comprehensive method to characterize size-segregated PM organic content was developed, and evaluated during two field campaigns. Size-segregated particles were collected using a cascade impactor (Micro-Orifice Uniform Deposit Impactor) and a PM2.5 large volume sampler. A series of alkanes and polycyclic aromatic hydrocarbons (PAHs) were solvent extracted and quantified using a gas chromatograph coupled with a mass spectrometer (GC/MS). Large volume injections were performed using a programmable temperature vaporization (PTV) inlet to lower detection limits. The developed analysis method was evaluated during the 2001 and 2002 Intercomparison Exercise Program on Organic Contaminants in PM2.5 Air Particulate Matter led by the US National Institute of Standards and Technology (NIST). Ambient samples were collected in May 2002 as part of the Tampa Bay Regional Atmospheric Chemistry Experiment (BRACE) in Florida, USA and in July and August 2004 as part of the New England Air Quality Study - Intercontinental Transport and Chemical Transformation (NEAQS - ITCT) in New Hampshire, USA. Morphology of the collected particles was studied using scanning electron microscopy (SEM). Smaller particles (one micrometer or less) appeared to consist of solid cores surrounded by a liquid layer which is consistent with combustion particles and also possibly with particles formed and/or coated by secondary material like sulfate, nitrate and secondary organic aerosols. Source apportionment studies demonstrated the importance of stationary sources on the organic particulate matter observed at these two rural sites. Coal burning and biomass burning were found to be responsible for a large part of the observed PAHs during the field campaigns. Most of the measured PAHs were concentrated in particles smaller than one micrometer and linked to combustion sources. The presence of known carcinogenic PAHs in the respirable particles has strong importance for human health. Recommendations for method improvements and further studies are included.

Ubiquitous influence of wildfire emissions and secondary organic aerosol on summertime atmospheric aerosol in the forested Great Lakes region

NASA Astrophysics Data System (ADS)

Gunsch, Matthew J.; May, Nathaniel W.; Wen, Miao; Bottenus, Courtney L. H.; Gardner, Daniel J.; VanReken, Timothy M.; Bertman, Steven B.; Hopke, Philip K.; Ault, Andrew P.; Pratt, Kerri A.

2018-03-01

Long-range aerosol transport affects locations hundreds of kilometers from the point of emission, leading to distant particle sources influencing rural environments that have few major local sources. Source apportionment was conducted using real-time aerosol chemistry measurements made in July 2014 at the forested University of Michigan Biological Station near Pellston, Michigan, a site representative of the remote forested Great Lakes region. Size-resolved chemical composition of individual 0.5-2.0 µm particles was measured using an aerosol time-of-flight mass spectrometer (ATOFMS), and non-refractory aerosol mass less than 1 µm (PM1) was measured with a high-resolution aerosol mass spectrometer (HR-AMS). The field site was influenced by air masses transporting Canadian wildfire emissions and urban pollution from Milwaukee and Chicago. During wildfire-influenced periods, 0.5-2.0 µm particles were primarily aged biomass burning particles (88 % by number). These particles were heavily coated with secondary organic aerosol (SOA) formed during transport, with organics (average O/C ratio of 0.8) contributing 89 % of the PM1 mass. During urban-influenced periods, organic carbon, elemental carbon-organic carbon, and aged biomass burning particles were identified, with inorganic secondary species (ammonium, sulfate, and nitrate) contributing 41 % of the PM1 mass, indicative of atmospheric processing. With current models underpredicting organic carbon in this region and biomass burning being the largest combustion contributor to SOA by mass, these results highlight the importance for regional chemical transport models to accurately predict the impact of long-range transported particles on air quality in the upper Midwest, United States, particularly considering increasing intensity and frequency of Canadian wildfires.

Source apportionment of PM2.5 light extinction in an urban atmosphere in China.

PubMed

Lan, Zijuan; Zhang, Bin; Huang, Xiaofeng; Zhu, Qiao; Yuan, Jinfeng; Zeng, Liwu; Hu, Min; He, Lingyan

2018-01-01

Haze in China is primarily caused by high pollution of atmospheric fine particulates (PM 2.5 ). However, the detailed source structures of PM 2.5 light extinction have not been well established, especially for the roles of various organic aerosols, which makes haze management lack specified targets. This study obtained the mass concentrations of the chemical compositions and the light extinction coefficients of fine particles in the winter in Dongguan, Guangdong Province, using high time resolution aerosol observation instruments. We combined the positive matrix factor (PMF) analysis model of organic aerosols and the multiple linear regression method to establish a quantitative relationship model between the main chemical components, in particular the different sources of organic aerosols and the extinction coefficients of fine particles with a high goodness of fit (R 2 =0.953). The results show that the contribution rates of ammonium sulphate, ammonium nitrate, biomass burning organic aerosol (BBOA), secondary organic aerosol (SOA) and black carbon (BC) were 48.1%, 20.7%, 15.0%, 10.6%, and 5.6%, respectively. It can be seen that the contribution of the secondary aerosols is much higher than that of the primary aerosols (79.4% versus 20.6%) and are a major factor in the visibility decline. BBOA is found to have a high visibility destroying potential, with a high mass extinction coefficient, and was the largest contributor during some high pollution periods. A more detailed analysis indicates that the contribution of the enhanced absorption caused by BC mixing state was approximately 37.7% of the total particle absorption and should not be neglected. Copyright © 2017. Published by Elsevier B.V.

Polycyclic aromatic hydrocarbons over a tropical urban and a high altitude Himalayan Station in India: Temporal variation and source apportionment

NASA Astrophysics Data System (ADS)

Ray, Debajyoti; Chatterjee, Abhijit; Majumdar, Dipanjali; Ghosh, Sanjay K.; Raha, Sibaji

2017-11-01

The temporal variations and major sources of polycyclic aromatic hydrocarbons (PAH) intrinsic to PM10 were investigated over a tropical urban atmosphere on the Indo-Gangetic Plain (IGP) and for the first time over a high altitude urban atmosphere at eastern Himalaya in India. Samples were collected over Kolkata, a megacity and Darjeeling, a high altitude (2200 m asl) hill station in eastern India during the dry season (October 2015-May 2016). Fourteen PAHs were detected and quantified over Kolkata and Darjeeling during three consecutive seasons, viz., post-monsoon, winter and pre-monsoon. The total-PAHs concentrations were in the order of winter (78.08-146.71 ngm- 3) > post-monsoon (83.42-113.52 ngm- 3) > pre-monsoon (37.65-109.27 ngm- 3) at Kolkata, whereas post-monsoon (22.72-36.60 ngm- 3) > winter (8.52-28.43 ngm- 3) > pre-monsoon (5.45-13.34 ngm- 3) at Darjeeling. The observed seasonality of PAHs at Kolkata vis-a-vis Darjeeling has been explored in the light of anthropogenic activities, boundary layer dynamics and meteorological parameters such as temperature, relative humidity, wind speed and solar radiation. Negative correlation was observed between total-PAHs and temperature, wind speed and solar radiation over Kolkata and Darjeeling. The positive matrix factorization (PMF) model calculations suggested that coal (26%), petrol (24%) and diesel (17%) combustion, commercial and household kitchens (18%) and municipal solid waste incineration (15%) are the possible contributors to the PM10 associated PAHs over Kolkata whereas diesel (37%), commercial and household kitchens (23%), coal (21%) and petrol (20%) are the possible PM10 associated PAH sources over Darjeeling.

Fine mode aerosol chemistry over a rural atmosphere near the north-east coast of Bay of Bengal in India

NASA Astrophysics Data System (ADS)

Adak, Anandamay; Chatterjee, Abhijit; Ghosh, Sanjay; Raha, Sibaji; Roy, Arindam

2016-07-01

A study was conducted on the chemical characterization of fine mode aerosol or PM2.5 over a rural atmosphere near the coast of Bay of Bengal in eastern India. Samples were collected and analyzed during March 2013 - February 2014. The concentration of PM2.5 was found span over a wide range from as low as 3 µg m-3 to as high as 180 µg m-3. The average concentration of PM2.5 was 62 µg m-3. Maximum accumulation of fine mode aerosol was observed during winter whereas minimum was observed during monsoon. Water soluble ionic species of fine mode aerosol were characterized over this rural atmosphere. In spite of being situated near the coast of Bay of Bengal, we observed significantly higher concentrations for anthropogenic species like ammonium and sulphate. The concentrations of these two species were much higher than the sea-salt aerosols. Ammonium and sulphate contributed around 30 % to the total fine mode aerosols. Even dust aerosol species like calcium also showed higher concentrations. Chloride to sodium ratio was found to be much less than that in standard sea-water indicating strong interaction between sea-salt and anthropogenic aerosols. Use of fertilizers in various crop fields and human and animal wastes significantly increased ammonium in fine mode aerosols. Dust aerosol species were accumulated in the atmosphere which could be due to transport of finer dust species from nearby metropolis or locally generated. Non-sea-sulphate and nitrate showed significant contributions in fine mode aerosols having both local and transported sources. Source apportionment shows prominent emission sources of anthropogenic aerosols from local anthropogenic activities and transported from nearby Kolkata metropolis as well.

Weak acid extractable metals in Bramble Bay, Queensland, Australia: temporal behaviour, enrichment and source apportionment.

PubMed

Brady, James P; Ayoko, Godwin A; Martens, Wayde N; Goonetilleke, Ashantha

2015-02-15

Sediment samples were taken from six sampling sites in Bramble Bay, Queensland, Australia between February and November in 2012. They were analysed for a range of heavy metals including Al, Fe, Mn, Ti, Ce, Th, U, V, Cr, Co, Ni, Cu, Zn, As, Cd, Sb, Te, Hg, Tl and Pb. Fraction analysis, Enrichment Factors and Principal Component Analysis-Absolute Principal Component Scores (PCA-APCS) were carried out in order to assess metal pollution, potential bioavailability and source apportionment. Cr and Ni exceeded the Australian Interim Sediment Quality Guidelines at some sampling sites, while Hg was found to be the most enriched metal. Fraction analysis identified increased weak acid soluble Hg and Cd during the sampling period. Source apportionment via PCA-APCS found four sources of metals pollution, namely, marine sediments, shipping, antifouling coatings and a mixed source. These sources need to be considered in any metal pollution control measure within Bramble Bay. Copyright © 2014 Elsevier Ltd. All rights reserved.

Stable carbon isotopes and levoglucosan for PM2.5 elemental carbon source apportionments in the largest city of Northwest China

NASA Astrophysics Data System (ADS)

Zhao, Zhuzi; Cao, Junji; Zhang, Ting; Shen, Zhenxing; Ni, Haiyan; Tian, Jie; Wang, Qiyuan; Liu, Suixin; Zhou, Jiamao; Gu, Jian; Shen, Ganzhou

2018-07-01

Stable carbon isotopes provide information on aerosol sources, but no extensive long-term studies of these isotopes have been conducted in China, and they have mainly been used for qualitative rather than quantitative purposes. Here, 24 h PM2.5 samples (n = 58) were collected from July 2008 to June 2009 at Xi'an, China. The concentrations of organic and elemental carbon (OC and EC), water-soluble OC, and the stable carbon isotope abundances of OC and EC were determined. In spring, summer, autumn and winter, the mean stable carbon isotope in OC (δ13COC) were -26.4 ± 0.6, -25.8 ± 0.7, -25.0 ± 0.6 and -24.4 ± 0.8‰, respectively, and the corresponding δ13CEC values were -25.5 ± 0.4, -25.5 ± 0.8, -25.2 ± 0.7 and -23.7 ± 0.6‰. Large δ13CEC and δ13COC values in winter can be linked to the burning coal for residential heating. Less biomass is burned during spring and summer than winter or fall (manifested in the levels of levoglucosan, i.e., 178, 85, 370, 935 ng m-3 in spring, summer, autumn, and winter), and the more negative δ13COC in the warmer months can be explained by the formation of secondary organic aerosols. A levoglucosan tracer method combined with an isotope mass balance analysis indicated that biomass burning accounted for 1.6-29.0% of the EC, and the mean value in winter (14.9 ± 7.5%) was 7 times higher than summer (2.1 ± 0.4%), with intermediate values of 6.1 ± 5.6 and 4.5 ± 2.4% in autumn and spring. Coal combustion accounted for 45.9 ± 23.1% of the EC overall, and the percentages were 63.0, 37.2, 36.7, and 33.7% in winter, autumn, summer and spring respectively. Motor vehicles accounted for 46.6 ± 26.5% of the annual EC, and these contributed over half (56.7-61.8%) of the EC in all seasons except winter. Correlations between motor vehicle-EC and coal combustion-EC with established source indicators (B(ghi)P and As) support the source apportionment results. This paper describes a simple and accurate method for apportioning the sources of EC, and the results may be beneficial for developing model simulations as well as controlling strategies in future.

26 CFR 1.861-8 - Computation of taxable income from sources within the United States and from other sources and...

Code of Federal Regulations, 2010 CFR

2010-04-01

... income. [Reserved]. For guidance, see § 1.861-8T(c)(1). (2) Apportionment based on assets. [Reserved.... [Reserved]. For guidance, see § 1.861-8T(d)(2). (e) Allocation and apportionment of certain deductions—(1... section. (2) Interest. [Reserved]. For guidance, see § 1.861-8T(e)(2). (3) Research and experimental...

Argon offline-AMS source apportionment of organic aerosol over yearly cycles for an urban, rural, and marine site in northern Europe

NASA Astrophysics Data System (ADS)

Bozzetti, Carlo; Sosedova, Yuliya; Xiao, Mao; Daellenbach, Kaspar R.; Ulevicius, Vidmantas; Dudoitis, Vadimas; Mordas, Genrik; Byčenkienė, Steigvilė; Plauškaitė, Kristina; Vlachou, Athanasia; Golly, Benjamin; Chazeau, Benjamin; Besombes, Jean-Luc; Baltensperger, Urs; Jaffrezo, Jean-Luc; Slowik, Jay G.; El Haddad, Imad; Prévôt, André S. H.

2017-01-01

The widespread use of Aerodyne aerosol mass spectrometers (AMS) has greatly improved real-time organic aerosol (OA) monitoring, providing mass spectra that contain sufficient information for source apportionment. However, AMS field deployments remain expensive and demanding, limiting the acquisition of long-term datasets at many sampling sites. The offline application of aerosol mass spectrometry entailing the analysis of nebulized water extracted filter samples (offline-AMS) increases the spatial coverage accessible to AMS measurements, being filters routinely collected at many stations worldwide. PM1 (particulate matter with an aerodynamic diameter < 1 µm) filter samples were collected during an entire year in Lithuania at three different locations representative of three typical environments of the southeast Baltic region: Vilnius (urban background), Rūgšteli\\vskis (rural terrestrial), and Preila (rural coastal). Aqueous filter extracts were nebulized in Ar, yielding the first AMS measurements of water-soluble atmospheric organic aerosol (WSOA) without interference from air fragments. This enables direct measurement of the CO+ fragment contribution, whose intensity is typically assumed to be equal to that of CO2+. Offline-AMS spectra reveal that the water-soluble CO2+ : CO+ ratio not only shows values systematically > 1 but is also dependent on season, with lower values in winter than in summer. AMS WSOA spectra were analyzed using positive matrix factorization (PMF), which yielded four factors. These factors included biomass burning OA (BBOA), local OA (LOA) contributing significantly only in Vilnius, and two oxygenated OA (OOA) factors, summer OOA (S-OOA) and background OOA (B-OOA), distinguished by their seasonal variability. The contribution of traffic exhaust OA (TEOA) was not resolved by PMF due to both low concentrations and low water solubility. Therefore, the TEOA concentration was estimated using a chemical mass balance approach, based on the concentrations of hopanes, specific markers of traffic emissions. AMS-PMF source apportionment results were consistent with those obtained from PMF applied to marker concentrations (i.e., major inorganic ions, OC / EC, and organic markers including polycyclic aromatic hydrocarbons and their derivatives, hopanes, long-chain alkanes, monosaccharides, anhydrous sugars, and lignin fragmentation products). OA was the largest fraction of PM1 and was dominated by BBOA during winter with an average concentration of 2 µg m-3 (53 % of OM), while S-OOA, probably related to biogenic emissions, was the prevalent OA component during summer with an average concentration of 1.2 µg m-3 (45 % of OM). PMF ascribed a large part of the CO+ explained variability (97 %) to the OOA and BBOA factors. Accordingly, we discuss a new CO+ parameterization as a function of CO2+ and C2H4O2+ fragments, which were selected to describe the variability of the OOA and BBOA factors.

In situ measurement and source apportionment of aerosols in the Kathmandu valley, Nepal, April 2015.

NASA Astrophysics Data System (ADS)

DeCarlo, P. F.; Werden, B.; Goetz, J. D.; Giordano, M.; Bhave, P.; Jayarathne, T. S.; Stockwell, C.; Christian, T. J.; Nadler, W.; Panday, A. K.; Yokelson, R. J.; Stone, E. A.

2017-12-01

The Kathmandu Valley in Nepal is home to over 2.5 Million people, and is one of the fastest growing metropolitan areas in South Asia. It is subject to extreme pollution events due to numerous unregulated localized pollution sources and regional transport from the Indo-Gangetic Plain (IGP). Over 10% of Nepali fatalities are from lung disorders, making it the most common cause of death in the country. Previous field work has studied gas species, wintertime VOCs and PM in the valley. The Nepal Ambient Measurement and Site Testing Experiment [NAMaSTE] is the first deployment of a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) in Nepal and allows for a more comprehensive analysis of aerosol species and their source contributions. Ambient measurements for the NAMaSTE campaign were made in Bode, 8 km east of Kathmandu. Intensive measurements were made in April 2015, but cut short by the 2015 Gorka earthquake. HR-ToF-AMS measurements provided detailed chemical composition information on particulate matter in the valley. Ancillary measurements of chemical species CO, CO2, CH4, H2O, O3, NOx, BC and PM were carried out and compared to AMS data and meteorological parameters. AMS species show a clear diurnal pattern, with extremely elevated concentrations in the morning, with a wind shift to westerly in the afternoon. PMF was performed on the ambient data set, and mass spectral data was compared to source mass spectra generated from emission testing of various local sources measured during the campaign. The mean concentration of PM2.5 was 83 ± 45 µg/m3, which is above the 24 hour WHO exposure threshold of 25 µg/m3 and annual continous exposure limit of 10 µg/m3­­. Localized sources of anthropogenic emissions such as garbage burning, coal for brick kilns, dung and biomass burning for cooking and agriculture are likely sources of elevated pollutant emissions. Unmitigated burning of trash and biomass coupled with irregular fuels are a major source of pollutant species and aerosols in the undeveloped world.

A modified receptor model for source apportionment of heavy metal pollution in soil.

PubMed

Huang, Ying; Deng, Meihua; Wu, Shaofu; Japenga, Jan; Li, Tingqiang; Yang, Xiaoe; He, Zhenli

2018-07-15

Source apportionment is a crucial step toward reduction of heavy metal pollution in soil. Existing methods are generally based on receptor models. However, overestimation or underestimation occurs when they are applied to heavy metal source apportionment in soil. Therefore, a modified model (PCA-MLRD) was developed, which is based on principal component analysis (PCA) and multiple linear regression with distance (MLRD). This model was applied to a case study conducted in a peri-urban area in southeast China where soils were contaminated by arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb). Compared with existing models, PCA-MLRD is able to identify specific sources and quantify the extent of influence for each emission. The zinc (Zn)-Pb mine was identified as the most important anthropogenic emission, which affected approximately half area for Pb and As accumulation, and approximately one third for Cd. Overall, the influence extent of the anthropogenic emissions decreased in the order of mine (3 km) > dyeing mill (2 km) ≈ industrial hub (2 km) > fluorescent factory (1.5 km) > road (0.5 km). Although algorithm still needs to improved, the PCA-MLRD model has the potential to become a useful tool for heavy metal source apportionment in soil. Copyright © 2018 Elsevier B.V. All rights reserved.

Source apportionment of airborne particles in commercial aircraft cabin environment: Contributions from outside and inside of cabin

NASA Astrophysics Data System (ADS)

Li, Zheng; Guan, Jun; Yang, Xudong; Lin, Chao-Hsin

2014-06-01

Airborne particles are an important type of air pollutants in aircraft cabin. Finding sources of particles is conducive to taking appropriate measures to remove them. In this study, measurements of concentration and size distribution of particles larger than 0.3 μm (PM>0.3) were made on nine short haul flights from September 2012 to March 2013. Particle counts in supply air and breathing zone air were both obtained. Results indicate that the number concentrations of particles ranged from 3.6 × 102 counts L-1 to 1.2 × 105 counts L-1 in supply air and breathing zone air, and they first decreased and then increased in general during the flight duration. Peaks of particle concentration were found at climbing, descending, and cruising phases in several flights. Percentages of particle concentration in breathing zone contributed by the bleed air (originated from outside) and cabin interior sources were calculated. The bleed air ratios, outside airflow rates and total airflow rates were calculated by using carbon dioxide as a ventilation tracer in five of the nine flights. The calculated results indicate that PM>0.3 in breathing zone mainly came from unfiltered bleed air, especially for particle sizes from 0.3 to 2.0 μm. And for particles larger than 2.0 μm, contributions from the bleed air and cabin interior were both important. The results would be useful for developing better cabin air quality control strategies.

Source apportionment of submicron organic aerosol collected from Atlanta, Georgia, during 2014-2015 using the aerosol chemical speciation monitor (ACSM)

NASA Astrophysics Data System (ADS)

Rattanavaraha, Weruka; Canagaratna, Manjula R.; Budisulistiorini, Sri Hapsari; Croteau, Philip L.; Baumann, Karsten; Canonaco, Francesco; Prevot, Andre S. H.; Edgerton, Eric S.; Zhang, Zhenfa; Jayne, John T.; Worsnop, Douglas R.; Gold, Avram; Shaw, Stephanie L.; Surratt, Jason D.

2017-10-01

The Aerodyne Aerosol Chemical Speciation Monitor (ACSM) was redeployed at the Jefferson Street (JST) site in downtown Atlanta, Georgia (GA) for 1 year (March 20, 2014-February 08, 2015) to chemically characterize non-refractory submicron particulate matter (NR-PM1) in near real-time and to assess whether organic aerosol (OA) types and amounts change from year-to-year. Submicron organic aerosol (OA) mass spectra were analyzed by season using multilinear engine (ME-2) to apportion OA subtypes to potential sources and chemical processes. A suite of real-time collocated measurements from the Southeastern Aerosol Research and Characterization (SEARCH) network was compared with ME-2 factor solutions to aid in the interpretation of OA subtypes during each season. OA tracers measured from high-volume filter samples using gas chromatography interfaced with electron ionization-mass spectrometry (GC/EI-MS) also aided in identifying OA sources. The initial application of ME-2 to the yearlong ACSM dataset revealed that OA source apportionment by season was required to better resolve sporadic OA types. Spring and fall OA mass spectral datasets were separated into finer periods to capture potential OA sources resulting from non-homogeneous emissions during transitioning periods. NR-PM1 was highest in summer (16.7 ± 8.4 μg m-3) and lowest in winter (8.0 ± 5.7 μg m-3), consistent with prior studies. OA dominated NR-PM1 mass (56-74% on average) in all seasons. Hydrocarbon-like OA (HOA) from primary emissions was observed in all seasons, averaging 5-22% of total OA mass. Strong correlations of HOA with carbon monoxide (CO) (R = 0.71-0.88) and oxides of nitrogen (NOx) (R = 0.55-0.79) indicated that vehicular traffic was the likely source. Biomass burning OA (BBOA) was observed in all seasons, with lower contributions (2%) in summer and higher in colder seasons (averaging 8-20% of total OA mass). BBOA correlated strongly with levoglucosan (R = 0.78-0.95) during colder seasons, which supports that BBOA is likely derived from fresh biomass/residential burning. However, weaker correlation with levoglucosan (R = 0.38) in summer suggested a more aged aerosol. During warmer seasons, OA from the reactive uptake of isoprene epoxydiols (IEPOX) onto acidic sulfate aerosol was resolved by ME-2 (denoted as IEPOX-OA), averaging 25-29% of the total OA mass. Temporal variation of IEPOX-OA was nearly coincident with that of 91Fac OA (a factor dominated by a distinct ion at m/z 91). The largest contribution of IEPOX-OA to total OA (29%) was found in summer, whereas the largest contribution of 91Fac to total OA (24%) occurred in early fall. Moderate negative correlation between IEPOX-OA and aerosol acidity was observed during late spring (-0.67) and summer (-0.42), consistent with laboratory studies showing that IEPOX-OA is enhanced in the presence of acidic aerosols. Finally, the largest OA mass in all seasons (46-70% of total OA) was derived from oxygenated OA denoted as low-volatility oxygenated OA (LV-OOA) and semi-volatile oxygenated OA (SV-OOA).

Demonstrating PM2.5 and road-side dust pollution by heavy metals along Thika superhighway in Kenya, sub-Saharan Africa.

PubMed

Maina, E G; Gachanja, A N; Gatari, M J; Price, H

2018-03-27

This study assessed the level of heavy metal in roadside dust and PM 2.5 mass concentrations along Thika superhighway in Kenya. Thika superhighway is one of the busiest roads in Kenya, linking Thika town with Nairobi. Triplicate road dust samples collected from 12 locations were analysed for lead (Pb), chromium (Cr), cadmium (Cd), nickel (Ni), zinc (Zn), and copper (Cu) using atomic absorption spectrophotometry (AAS). PM 2.5 samples were collected on pre-weighed Teflon filters using a BGI personal sampler and the filters were then reweighed. The ranges of metal concentrations were 39-101 μg/g for Cu, 95-262 μg/g for Zn, 9-28 μg/g for Cd, 14-24 μg/g for Ni, 13-30 μg/g for Cr, and 20-80 μg/g for Pb. The concentrations of heavy metals were generally highly correlated, indicating a common anthropogenic source of the pollutants. The results showed that the majority of the measured heavy metals were above the background concentration, and in particular, Cd, Pb, and Zn levels indicated moderate to high contamination. Though not directly comparable due to different sampling timeframes (8 h in this study and 24 h for guideline values), PM 2.5 for all sites exceeds the daily WHO PM 2.5 guidelines of 25 μg/m 3 . This poses a health risk to people using and working close to Thika superhighway, for example, local residents, traffic police, street vendors, and people operating small businesses. PM 2.5 levels were higher for sites closer to Nairobi which could be attributed to increased vehicular traffic towards Nairobi from Thika. This study provides some evidence of the air pollution problem arising from vehicular traffic in developing parts of the world and gives an indication of the potential health impacts. It also highlights the need for source apportionment studies to determine contributions of anthropogenic emissions to air pollution, as well as long-term sampling studies that can be used to fully understand spatiotemporal patterns in air pollution within developing regions.

ATMOSPHERIC AEROSOL SOURCE-RECEPTOR RELATIONSHIPS: THE ROLE OF COAL-FIRED POWER PLANTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen L. Robinson; Spyros N. Pandis; Cliff I. Davidson

2005-04-01

This report describes the technical progress made on the Pittsburgh Air Quality Study (PAQS) during the period of September 2004 through February 2005. Significant progress was made this project period on the analysis of ambient data, source apportionment, and deterministic modeling activities. The major experimental achievement this project period was the characterization of the mercury and fine particle emissions from two modern, large, commercial pulverized coal boilers. This testing completes the field work component of the Source Characterization Activity. This report highlights results from mercury emission measurements made using a dilution sampler. The measurements clearly indicate that mercury is beingmore » transformed from an oxidized to an elemental state within the dilution. However, wall effects are significant making it difficult to determine whether or not these changes occur in the gas phase or due to some interaction with the sampler walls. This report also presents results from an analysis that uses spherical aluminum silicate (SAS) particles as a marker for primary PM{sub 2.5} emitted from coal combustion. Primary emissions from coal combustion contribute only a small fraction of the PM{sub 2.5} mass (less than 1.5% in the summer and less than 3% in the winter) at the Pittsburgh site. Ambient SAS concentrations also appear to be reasonably spatially homogeneous. Finally, SAS emission factors measured at pilot-scale are consistent with measurements made at full-scale. This report also presents results from applying the Unmix and PMF models to estimate the contribution of different sources to the PM{sub 2.5} mass concentrations in Pittsburgh using aerosol composition information. Comparison of the two models shows similar source composition and contribution for five factors: crustal material, nitrate, an Fe, Mn, and Zn factor, specialty steel production, and a cadmium factor. PMF found several additional factors. Comparison between source contributions for the similar factors shows reasonable agreement between the two models. The sulfate factor shows the highest contribution to local PM{sub 2.5} with an annual average contribution of approximately 28% (from PMF). The nitrate, crustal material, and primary OC and EC factors also show significant contributions on the order of 10-14%. The sulfate factor is affected by photochemistry and therefore shows maximum values in summer.« less

Aliphatic and polycyclic aromatic hydrocarbons characterisation of Coimbra and Oporto PM2.5 urban aerosol

NASA Astrophysics Data System (ADS)

Rocha, A. C.; Mirante, F.; Gonçalves, C.; Nunes, T.; Alves, C.; Evtyugina, M.; Kowacz, M.; Pio, C.; Rocha, C.; Vasconcelos, T.

2009-04-01

The concentration of organic pollutants in urban areas is mostly due to incomplete combustion from vehicles, industries and domestic heating. Some of these compounds, principally the aliphatic (ALIPH) and polycyclic aromatic hydrocarbons (PAHs) promote harmful effects in human health. The determination of the ALIPH and PAHs concentration levels and their possible emission sources are useful for air quality management and source apportionment studies. In order to estimate and compare the ambient concentrations and establish the main sources of these compounds, the fine fraction of the atmospheric particulate matter (PM2.5) was collected simultaneously in Oporto and Coimbra during summer and winter seasons using a high volume sampler. The organic compounds were extracted from the particulate matter, under reflux with dichloromethane and the total organic extract (TOE) was fractionated by flash chromatography using five different eluents with increasing polarity. The hydrocarbon fractions were analysed by gas chromatography/mass spectrometry (GC/MS). Here we present and discuss the qualitative and quantitative composition of the aliphatic and aromatic fractions present in PM2.5 samples from both cities. The homologous series of C14 to C34 n-alkanes, isoprenoid hydrocarbons (pristane and phytane), PAHs and some petroleum markers have been identified and quantified. With the purpose of identifying the possible sources, various molecular diagnostic ratios were calculated. The global carbon preference index (CPI) closer to the unity, the large concentration of the unresolved complex mixture (UCM) and the presence of PAHs indicate that motor vehicle exhaust was the main emission source of the aliphatic and polycyclic aromatic fractions of Oporto and Coimbra aerosol, especially in the first city. Also, the remarkable presence of petroleum biomarkers such, as hopanes, confirms the previous results. Concentration ratios between PAHs were calculated and used to assign emission sources. The abundance and the sources of these organic pollutants for the two cities are discussed and compared taking into account the local/regional characteristics. Acknowledgement: The authors would like to thank Fundação para a Ciência e Tecnologia (FCT) for the financial support through the project POCI/AMB/60267/2004 which provided funding for the work presented here.

Spatial and temporal variability of source contributions to ambient PM10 during winter in Augsburg, Germany using organic and inorganic tracers.

PubMed

Qadir, R M; Schnelle-Kreis, J; Abbaszade, G; Arteaga-Salas, J M; Diemer, J; Zimmermann, R

2014-05-01

Daily PM10 samples were collected during a one-month sampling campaign from February 13 to March 12, 2008 at eight different sampling sites in Augsburg, Southern Germany. Source apportionment was performed to identify the main sources and related contributions by analysis of organic and inorganic tracers. Nine factors were separated comprising: solid fuel combustion, traffic-related emissions, secondary inorganics, and mixed sources. Spatiotemporal variation of the source contributions was evaluated using the Pearson correlation coefficient (r) and coefficient of divergence (COD). All factors (except hopanes and mixed sources) showed moderate to high (0.60.8) correlation coefficients between the eight sites and were distributed heterogeneously. Secondary sulfate and secondary nitrate factors were relatively more uniformly distributed (compared to other factors) with lower medians of COD value (0.47 and 0.56, respectively) and higher correlation values (r=0.97 and 0.85, respectively). The maximum daily average contribution for coal & wood combustion factor was observed at the LfU suburban site (4.0 μg m(-3)); wood combustion factor at the LSW residential site (5.1 μg m(-3)) ; diesel & fuel oil consumption factor at the Bifa suburban and BP urban sites (both 2.5 μg m(-3)); road dust & tram factor at the KP traffic site (16.2 μg m(-3)) and the BP urban site (6.6 μg m(-3)); hopanes factor at the BP urban and Bifa suburban sites (both 0.7 μg m(-3)); and de-icing NaCl factor at the KP traffic site (4.8 μg m(-3)). Secondary sulfate and secondary nitrate factors had approximately similar contributions (6.2 μg m(-3) and 4.3 μg m(-3), respectively) at all sites. Mixed sources factor had the highest daily average contribution to PM10 mass at the KP traffic site (7.0 μg m(-3)). Copyright © 2013 Elsevier Ltd. All rights reserved.

Source apportionment of emissions from light-duty gasoline vehicles and other sources in the United States for ozone and particulate matter.

PubMed

Vijayaraghavan, Krish; Lindhjem, Chris; Koo, Bonyoung; DenBleyker, Allison; Tai, Edward; Shah, Tejas; Alvarez, Yesica; Yarwood, Greg

2016-02-01

Federal Tier 3 motor vehicle emission and fuel sulfur standards have been promulgated in the United States to help attain air quality standards for ozone and PM2.5 (particulate matter with an aerodynamic diameter <2.5 μm). The authors modeled a standard similar to Tier 3 (a hypothetical nationwide implementation of the California Low Emission Vehicle [LEV] III standards) and prior Tier 2 standards for on-road gasoline-fueled light-duty vehicles (gLDVs) to assess incremental air quality benefits in the United States (U.S.) and the relative contributions of gLDVs and other major source categories to ozone and PM2.5 in 2030. Strengthening Tier 2 to a Tier 3-like (LEV III) standard reduces the summertime monthly mean of daily maximum 8-hr average (MDA8) ozone in the eastern U.S. by up to 1.5 ppb (or 2%) and the maximum MDA8 ozone by up to 3.4 ppb (or 3%). Reducing gasoline sulfur content from 30 to 10 ppm is responsible for up to 0.3 ppb of the improvement in the monthly mean ozone and up to 0.8 ppb of the improvement in maximum ozone. Across four major urban areas-Atlanta, Detroit, Philadelphia, and St. Louis-gLDV contributions range from 5% to 9% and 3% to 6% of the summertime mean MDA8 ozone under Tier 2 and Tier 3, respectively, and from 7% to 11% and 3% to 7% of the maximum MDA8 ozone under Tier 2 and Tier 3, respectively. Monthly mean 24-hr PM2.5 decreases by up to 0.5 μg/m(3) (or 3%) in the eastern U.S. from Tier 2 to Tier 3, with about 0.1 μg/m(3) of the reduction due to the lower gasoline sulfur content. At the four urban areas under the Tier 3 program, gLDV emissions contribute 3.4-5.0% and 1.7-2.4% of the winter and summer mean 24-hr PM2.5, respectively, and 3.8-4.6% and 1.5-2.0% of the mean 24-hr PM2.5 on days with elevated PM2.5 in winter and summer, respectively. Following U.S. Tier 3 emissions and fuel sulfur standards for gasoline-fueled passenger cars and light trucks, these vehicles are expected to contribute less than 6% of the summertime mean daily maximum 8-hr ozone and less than 7% and 4% of the winter and summer mean 24-hr PM2.5 in the eastern U.S. in 2030. On days with elevated ozone or PM2.5 at four major urban areas, these vehicles contribute less than 7% of ozone and less than 5% of PM2.5, with sources outside North America and U.S. area source emissions constituting some of the main contributors to ozone and PM2.5, respectively.

Gaseous and particulate emissions from prescribed burning in Georgia.

PubMed

Lee, Sangil; Baumann, Karsten; Schauer, James J; Sheesley, Rebecca J; Naeher, Luke P; Meinardi, Simone; Blake, Donald R; Edgerton, Eric S; Russell, Armistead G; Clements, Mark

2005-12-01

Prescribed burning is a significant source of fine particulate matter (PM2.5) in the southeastern United States. However, limited data exist on the emission characteristics from this source. Various organic and inorganic compounds both in the gas and particle phase were measured in the emissions of prescribed burnings conducted at two pine-dominated forest areas in Georgia. The measurements of volatile organic compounds (VOCs) and PM2.5 allowed the determination of emission factors for the flaming and smoldering stages of prescribed burnings. The VOC emission factors from smoldering were distinctly higher than those from flaming except for ethene, ethyne, and organic nitrate compounds. VOC emission factors show that emissions of certain aromatic compounds and terpenes such as alpha and beta-pinenes, which are important precursors for secondary organic aerosol (SOA), are much higher from active prescribed burnings than from fireplace wood and laboratory open burning studies. Levoglucosan is the major particulate organic compound (POC) emitted for all these studies, though its emission relative to total organic carbon (mg/g OC) differs significantly. Furthermore, cholesterol, an important fingerprint for meat cooking, was observed only in our in situ study indicating a significant release from the soil and soil organisms during open burning. Source apportionment of ambient primary fine particulate OC measured at two urban receptor locations 20-25 km downwind yields 74 +/- 11% during and immediately after the burns using our new in situ profile. In comparison with the previous source profile from laboratory simulations, however, this OC contribution is on average 27 +/- 5% lower.

Realtime chemical characterization of post monsoon organic aerosols in a polluted urban city: Sources, composition, and comparison with other seasons.

PubMed

Chakraborty, Abhishek; Mandariya, Anil Kumar; Chakraborti, Ruparati; Gupta, Tarun; Tripathi, S N

2018-01-01

Real time chemical characterization of non-refractory submicron aerosols (NR-PM 1 ) was carried out during post monsoon (September-October) via Aerosol Mass Spectrometer (AMS) at a polluted urban location of Kanpur, India. Organic aerosol (OA) was found to be the dominant species with 58% contribution to total NR-PM 1 mass, followed by sulfate (16%). Overall, OA was highly oxidized (average O/C = 0.66) with the dominance of oxidized OAs (60% of total OA) as revealed by source apportionment. Oxidized nature of OA was also supported by very high OC/EC ratios (average = 8.2) obtained from simultaneous offline filter sampling. High and low OA loading periods have very dramatic effects on OA composition and oxidation. OA O/C ratios during lower OA loading periods were on average 30% higher than the same from high loading periods with significant changes in types and relative contribution from oxidized OAs (OOA). Comparison of OA sources and chemistry among post monsoon and other seasons revealed significant differences. Characteristics of primary OAs remain very similar, but features of OOAs showed substantial changes from one season to another. Winter had lowest OOA contribution to total OA but similar overall O/C ratios as other seasons. This reveals that processing of primary OAs, local atmospheric chemistry, and regional contributions can significantly alter OA characteristics from one season to another. This study provides interesting insights into the seasonal variations of OA sources and evolution in a very polluted and complex environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Source origin of trace elements in PM from regional background, urban and industrial sites of Spain

NASA Astrophysics Data System (ADS)

Querol, X.; Viana, M.; Alastuey, A.; Amato, F.; Moreno, T.; Castillo, S.; Pey, J.; de la Rosa, J.; Sánchez de la Campa, A.; Artíñano, B.; Salvador, P.; García Dos Santos, S.; Fernández-Patier, R.; Moreno-Grau, S.; Negral, L.; Minguillón, M. C.; Monfort, E.; Gil, J. I.; Inza, A.; Ortega, L. A.; Santamaría, J. M.; Zabalza, J.

Despite their significant role in source apportionment analysis, studies dedicated to the identification of tracer elements of emission sources of atmospheric particulate matter based on air quality data are relatively scarce. The studies describing tracer elements of specific sources currently available in the literature mostly focus on emissions from traffic or large-scale combustion processes (e.g. power plants), but not on specific industrial processes. Furthermore, marker elements are not usually determined at receptor sites, but during emission. In our study, trace element concentrations in PM 10 and PM 2.5 were determined at 33 monitoring stations in Spain throughout the period 1995-2006. Industrial emissions from different forms of metallurgy (steel, stainless steel, copper, zinc), ceramic and petrochemical industries were evaluated. Results obtained at sites with no significant industrial development allowed us to define usual concentration ranges for a number of trace elements in rural and urban background environments. At industrial and traffic hotspots, average trace metal concentrations were highest, exceeding rural background levels by even one order of magnitude in the cases of Cr, Mn, Cu, Zn, As, Sn, W, V, Ni, Cs and Pb. Steel production emissions were linked to high levels of Cr, Mn, Ni, Zn, Mo, Cd, Se and Sn (and probably Pb). Copper metallurgy areas showed high levels of As, Bi, Ga and Cu. Zinc metallurgy was characterised by high levels of Zn and Cd. Glazed ceramic production areas were linked to high levels of Zn, As, Se, Zr, Cs, Tl, Li, Co and Pb. High levels of Ni and V (in association) were tracers of petrochemical plants and/or fuel-oil combustion. At one site under the influence of heavy vessel traffic these elements could be considered tracers (although not exclusively) of shipping emissions. Levels of Zn-Ba and Cu-Sb were relatively high in urban areas when compared with industrialised regions due to tyre and brake abrasion, respectively.

Single particle characterization, source apportionment, and aging effects of ambient aerosols in Southern California

NASA Astrophysics Data System (ADS)

Shields, Laura Grace

Composed of a mixture of chemical species and phases and existing in a variety of shapes and sizes, atmospheric aerosols are complex and can have serious influence on human health, the environment, and climate. In order to better understand the impact of aerosols on local to global scales, detailed measurements on the physical and chemical properties of ambient particles are essential. In addition, knowing the origin or the source of the aerosols is important for policymakers to implement targeted regulations and effective control strategies to reduce air pollution in their region. One of the most ground breaking techniques in aerosol instrumentation is single particle mass spectrometry (SPMS), which can provide online chemical composition and size information on the individual particle level. The primary focus of this work is to further improve the ability of one specific SPMS technique, aerosol time-of-flight mass spectrometry (ATOFMS), for the use of identifying the specific origin of ambient aerosols, which is known as source apportionment. The ATOFMS source apportionment method utilizes a library of distinct source mass spectral signatures to match the chemical information of the single ambient particles. The unique signatures are obtained in controlled source characterization studies, such as with the exhaust emissions of heavy duty diesel vehicles (HDDV) operating on a dynamometer. The apportionment of ambient aerosols is complicated by the chemical and physical processes an individual particle can undergo as it spends time in the atmosphere, which is referred to as "aging" of the aerosol. Therefore, the performance of the source signature library technique was investigated on the ambient dataset of the highly aged environment of Riverside, California. Additionally, two specific subsets of the Riverside dataset (ultrafine particles and particles containing trace metals), which are known to cause adverse health effects, were probed in greater detail. Finally, the impact of large wildfires on the ambient levels of particulate matter in Southern California is discussed. The results of this work provide insight into single particles impacting the Southern California region, the relative source contributions to this region, and finally an examination of how atmospheric aging influences the ability to perform source apportionment.

An integrated approach to assess heavy metal source apportionment in peri-urban agricultural soils.

PubMed

Huang, Ying; Li, Tingqiang; Wu, Chengxian; He, Zhenli; Japenga, Jan; Deng, Meihua; Yang, Xiaoe

2015-12-15

Three techniques (Isotope Ratio Analysis, GIS mapping, and Multivariate Statistical Analysis) were integrated to assess heavy metal pollution and source apportionment in peri-urban agricultural soils. The soils in the study area were moderately polluted with cadmium (Cd) and mercury (Hg), lightly polluted with lead (Pb), and chromium (Cr). GIS Mapping suggested Cd pollution originates from point sources, whereas Hg, Pb, Cr could be traced back to both point and non-point sources. Principal component analysis (PCA) indicated aluminum (Al), manganese (Mn), nickel (Ni) were mainly inherited from natural sources, while Hg, Pb, and Cd were associated with two different kinds of anthropogenic sources. Cluster analysis (CA) further identified fertilizers, waste water, industrial solid wastes, road dust, and atmospheric deposition as potential sources. Based on isotope ratio analysis (IRA) organic fertilizers and road dusts accounted for 74-100% and 0-24% of the total Hg input, while road dusts and solid wastes contributed for 0-80% and 19-100% of the Pb input. This study provides a reliable approach for heavy metal source apportionment in this particular peri-urban area, with a clear potential for future application in other regions. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterization and source apportionment of particle number concentration at a semi-urban tropical environment.

PubMed

Khan, Md Firoz; Latif, Mohd Talib; Amil, Norhaniza; Juneng, Liew; Mohamad, Noorlin; Nadzir, Mohd Shahrul Mohd; Hoque, Hossain Mohammed Syedul

2015-09-01

Principal component analysis (PCA) and correlation have been used to study the variability of particle mass and particle number concentrations (PNC) in a tropical semi-urban environment. PNC and mass concentration (diameter in the range of 0.25->32.0 μm) have been measured from 1 February to 26 February 2013 using an in situ Grimm aerosol sampler. We found that the 24-h average total suspended particulates (TSP), particulate matter ≤10 μm (PM10), particulate matter ≤2.5 μm (PM2.5) and particulate matter ≤1 μm (PM1) were 14.37 ± 4.43, 14.11 ± 4.39, 12.53 ± 4.13 and 10.53 ± 3.98 μg m(-3), respectively. PNC in the accumulation mode (<500 nm) was the most abundant (at about 99 %). Five principal components (PCs) resulted from the PCA analysis where PC1 (43.8 % variance) predominates with PNC in the fine and sub-microme tre range. PC2, PC3, PC4 and PC5 explain 16.5, 12.4, 6.0 and 5.6 % of the variance to address the coarse, coarser, accumulation and giant fraction of PNC, respectively. Our particle distribution results show good agreement with the moderate resolution imaging spectroradiometer (MODIS) distribution.

Application of a source apportionment model in consideration of volatile organic compounds in an urban stream

USGS Publications Warehouse

Asher, W.E.; Luo, W.; Campo, K.W.; Bender, D.A.; Robinson, K.W.; Zogorski, J.S.; Pankow, J.F.

2007-01-01

Position-dependent concentrations of trichloroethylene and methyl-tert-butyl ether are considered for a 2.81-km section of the Aberjona River in Massachusetts, USA. This river flows through Woburn and Winchester (Massachusetts, USA), an area that is highly urbanized, has a long history of industrial activities dating to the early 1800s, and has gained national attention because of contamination from chlorinated solvent compounds in Woburn wells G and H. The river study section is in Winchester and begins approximately five stream kilometers downstream from the Woburn wells superfund site. Approximately 300 toxic release sites are documented in the watershed upstream from the terminus of the study section. The inflow to the river study section is considered one source of contamination. Other sources are the atmosphere, a tributary flow, and groundwater flows entering the river; the latter are categorized according to stream zone (1, 2, 3, etc.). Loss processes considered include outflows to groundwater and water-to-atmosphere transfer of volatile compounds. For both trichloroethylene and methyl-rerf-butyl ether, degradation is neglected over the timescale of interest. Source apportionment fractions with assigned values ??inflow, ??1, ??2, ??3, etc. are tracked by a source apportionment model. The strengths of the groundwater and tributary sources serve as fitting parameters when minimizing a reduced least squares statistic between water concentrations measured during a synoptic study in July 2001 versus predictions from the model. The model fits provide strong evidence of substantial unknown groundwater sources of trichloroethylene and methyl-tert-butyl ether amounting to tens of grams per day of trichloroethylene and methyl-tert-butyl ether in the river along the study section. Modeling in a source apportionment manner can be useful to water quality managers allocating limited resources for remediation and source control. ?? 2007 SETAC.

Toward Synchronous Evaluation of Source Apportionments for Atmospheric Concentration and Deposition of Sulfate Aerosol Over East Asia

NASA Astrophysics Data System (ADS)

Itahashi, S.

2018-03-01

Source apportionments for atmospheric concentration, dry deposition, and wet deposition of sulfate aerosol (SO42-) were synchronously evaluated over East Asia, a main source of anthropogenic sulfur dioxide (SO2) emissions. Estimating dry deposition was difficult owing to the difficulty of measuring deposition velocity directly; therefore, sensitivity simulations using two dry deposition schemes were conducted. Moreover, sensitivity simulations for different emission inventories, the largest uncertainty source in the air quality model, were also conducted. In total, four experimental settings were used. Model performance was verified for atmospheric concentration and wet deposition using a ground-based observation network in China, Korea, and Japan, and all four model settings captured the observations. The underestimation of wet deposition over China was improved by an adjusted approach that linearly scaled the modeled precipitation values to observations. The synchronous evaluation of source apportionments for atmospheric concentration and dry and wet deposition showed the dominant contribution of anthropogenic emissions from China to the atmospheric concentration and deposition in Japan. The contributions of emissions from volcanoes were more important for wet deposition than for atmospheric concentration. Differences in the dry deposition scheme and emission inventory did not substantially influence the relative ratio of source apportionments over Japan. Because the dry deposition was more attributed to local factors, the differences in dry deposition may be an important determinant of the source contributions from China to Japan. Verification of these findings, including the dry deposition velocity, is necessary for better understanding of the behavior of sulfur compound in East Asia.

Size distribution, characteristics and sources of heavy metals in haze episode in Beijing.

PubMed

Duan, Jingchun; Tan, Jihua; Hao, Jiming; Chai, Fahe

2014-01-01

Size segragated samples were collected during high polluted winter haze days in 2006 in Beijing, China. Twenty nine elements and 9 water soluble ions were determined. Heavy metals of Zn, Pb, Mn, Cu, As, Cr, Ni, V and Cd were deeply studied considering their toxic effect on human being. Among these heavy metals, the levels of Mn, As and Cd exceeded the reference values of National Ambient Air Quality Standard (GB3095-2012) and guidelines of World Health Organization. By estimation, high percentage of atmospheric heavy metals in PM2.5 indicates it is an effective way to control atmospheric heavy metals by PM2.5 controlling. Pb, Cd, and Zn show mostly in accumulation mode, V, Mn and Cu exist mostly in both coarse and accumulation modes, and Ni and Cr exist in all of the three modes. Considering the health effect, the breakthrough rates of atmospheric heavy metals into pulmonary alveoli are: Pb (62.1%) > As (58.1%) > Cd (57.9%) > Zn (57.7%) > Cu (55.8%) > Ni (53.5%) > Cr (52.2%) > Mn (49.2%) > V (43.5%). Positive matrix factorization method was applied for source apportionment of studied heavy metals combined with some marker elements and ions such as K, As, SO4(2-) etc., and four factors (dust, vehicle, aged and transportation, unknown) are identified and the size distribution contribution of them to atmospheric heavy metals are discussed.

Quantification of Aerosol Derived Particulate Matter and Trace gases in the Coastal Belt of Kochi, Kerala, India

NASA Astrophysics Data System (ADS)

H, S. C.

2016-02-01

Aerosol chemistry is a window to unravel the various environmental health hazard problems. This open forum which deals with the study of formation, interaction, transformation of aerosol species, which could enable in the assessment of biogeochemical cycling of anthropogenic and toxic species. It also preserves the temperature balance and reservoir and sink for nutrients, trace metals and organic species. An inventory of air pollutants is a proactive and necessary first step towards the control of air pollution. Surveys and studies on the sources of pollution and their apportionment to different sources are a pre-requisite for alleviating environmental disorder. The Kochi City (The Queen of Arabian Sea), Kerala, India is a fast growing industrial region where mounting urbanization has been affecting the quality of the atmospheric environment. Cochin estuarine environment is progressively affected by marine pollution concomitant by industrial hazardous chemicals and municipal waste. Further, rapid urbanization and industrialization has lead to lofting and large scale advection of these omnipresent species in the atmosphere. Studies were conducted to assess the significance and potential impact occupied to these ubiquitous species. The major gaseous pollutants include gases like sulphur dioxide, nitrogen dioxide, ammonia and particulate matter (PM). An attempt was performed to unravel the inorganic species in the atmosphere and programmed by means of quantification of PM10 and trace gases. Their distribution pattern and outcomes are inferred.

Source apportionment of 1 h semi-continuous data during the 2005 Study of Organic Aerosols in Riverside (SOAR) using positive matrix factorization

NASA Astrophysics Data System (ADS)

Eatough, Delbert J.; Grover, Brett D.; Woolwine, Woods R.; Eatough, Norman L.; Long, Russell; Farber, Robert

Positive matrix factorization (PMF2) was used to elucidate sources of fine particulate material (PM 2.5) for a study conducted during July and August 2005, in Riverside, CA. One-hour averaged semi-continuous measurements were made with a suite of instruments to provide PM 2.5 mass and chemical composition data. Total PM 2.5 mass concentrations (non-volatile plus semi-volatile) were measured with an R&P filter dynamic measurement system (FDMS TEOM) and a conventional TEOM monitor was used to measure non-volatile mass concentrations. PM 2.5 chemical species monitors included a dual-oven Sunset monitor to measure both non-volatile and semi-volatile carbonaceous material, an ion chromatographic-based monitor to measure sulfate and nitrate and an Anderson Aethalometer to measure black carbon (BC). Gas phase data including CO, NO 2, NO x and O 3 were also collected during the sampling period. In addition, single-particle measurements were made using aerosol time-of-flight mass spectrometry (ATOFMS). Twenty different single-particle types consistent with those observed in previous ATOFMS studies in Riverside were identified for the PMF2 analysis. Finally, time-of-flight aerosol mass spectrometry (ToF-AMS) provided data on markers of primary and secondary organic aerosol. Two distinct PMF2 analyses were performed. In analysis 1, all the data except for the ATOFMS and ToF-AMS data were used in an initial evaluation of sources at Riverside during the study. PMF2 was able to identify six factors from the data set corresponding to both primary and secondary sources, primarily from automobile emissions, diesel emissions, secondary nitrate formation, a secondary photochemical associated source, organic emissions and Basin transported pollutants. In analysis 2, the ATOFMS and ToF-AMS data were included in the analysis. In the second analysis, PMF2 was able to identify 16 factors with a variety of both primary and secondary factors being identified, corresponding to both primary and secondary material from both anthropogenic and natural sources. Based on relationships with Basin meteorology, the PMF identified source profiles and diurnal patterns in the source concentrations, sources were identified as being of local origin or resulting from transport of pollutants across the Basin due to onshore flow. Good agreement was observed between the PMF2 predicted mass and the FDMS measured mass for both analyses.

Trends in analytical techniques applied to particulate matter characterization: A critical review of fundaments and applications.

PubMed

Galvão, Elson Silva; Santos, Jane Meri; Lima, Ana Teresa; Reis, Neyval Costa; Orlando, Marcos Tadeu D'Azeredo; Stuetz, Richard Michael

2018-05-01

Epidemiological studies have shown the association of airborne particulate matter (PM) size and chemical composition with health problems affecting the cardiorespiratory and central nervous systems. PM also act as cloud condensation nuclei (CNN) or ice nuclei (IN), taking part in the clouds formation process, and therefore can impact the climate. There are several works using different analytical techniques in PM chemical and physical characterization to supply information to source apportionment models that help environmental agencies to assess damages accountability. Despite the numerous analytical techniques described in the literature available for PM characterization, laboratories are normally limited to the in-house available techniques, which raises the question if a given technique is suitable for the purpose of a specific experimental work. The aim of this work consists of summarizing the main available technologies for PM characterization, serving as a guide for readers to find the most appropriate technique(s) for their investigation. Elemental analysis techniques like atomic spectrometry based and X-ray based techniques, organic and carbonaceous techniques and surface analysis techniques are discussed, illustrating their main features as well as their advantages and drawbacks. We also discuss the trends in analytical techniques used over the last two decades. The choice among all techniques is a function of a number of parameters such as: the relevant particles physical properties, sampling and measuring time, access to available facilities and the costs associated to equipment acquisition, among other considerations. An analytical guide map is presented as a guideline for choosing the most appropriated technique for a given analytical information required. Copyright © 2018 Elsevier Ltd. All rights reserved.

A clustering algorithm for sample data based on environmental pollution characteristics

NASA Astrophysics Data System (ADS)

Chen, Mei; Wang, Pengfei; Chen, Qiang; Wu, Jiadong; Chen, Xiaoyun

2015-04-01

Environmental pollution has become an issue of serious international concern in recent years. Among the receptor-oriented pollution models, CMB, PMF, UNMIX, and PCA are widely used as source apportionment models. To improve the accuracy of source apportionment and classify the sample data for these models, this study proposes an easy-to-use, high-dimensional EPC algorithm that not only organizes all of the sample data into different groups according to the similarities in pollution characteristics such as pollution sources and concentrations but also simultaneously detects outliers. The main clustering process consists of selecting the first unlabelled point as the cluster centre, then assigning each data point in the sample dataset to its most similar cluster centre according to both the user-defined threshold and the value of similarity function in each iteration, and finally modifying the clusters using a method similar to k-Means. The validity and accuracy of the algorithm are tested using both real and synthetic datasets, which makes the EPC algorithm practical and effective for appropriately classifying sample data for source apportionment models and helpful for better understanding and interpreting the sources of pollution.

Characterisation of the organic composition of size segregated atmospheric particulate matter at traffic exposed and background sites in Madrid

NASA Astrophysics Data System (ADS)

Mirante, F.; Perez, R.; Alves, C.; Revuelta, M.; Pio, C.; Artiñano, B.; Nunes, T.

2010-05-01

The growing awareness of the impact of atmospheric particulate matter (PM) on climate, and the incompletely recognised but serious effects of anthropogenic aerosols on air quality and human health, have led to diverse studies involving almost exclusively the coarse or the fine PM fractions. However, these environmental effects, the PM formation processes and the source assignment depend greatly on the particle size distribution. The innovative character of this study consists in obtaining time series with a size-segregated detailed chemical composition of PM for differently polluted sites. In this perspective, a summer sampling campaign was carried out from 1 of June to 1 of July 2009. One of the sampling sites was located at a representative urban monitoring station (Escuelas Aguirre) belonging to the municipal network, located at a heavy traffic street intersection in downtown Madrid. Other sampling point was positioned within the CIEMAT area, located in the NW corner of the city, which can be considered an urban background or suburban site. Particulate matter was sampled with high volume cascade impactors at 4 size stages: 10-2.5, 2.5-0.95, 0.95-0.45 and < 0.45 µm. Daily sampling was carried out on quartz fibre filters. Based on meteorological conditions and PM mass concentrations, each one of the 7 groups of filters collected during the first week were combined with the corresponding filters of the third week. The same procedure was undertaken with samples of the second and fourth weeks. Filters of 0.95-0.45 and < 0.45 µm were pooled to obtain the PM0.95 organic composition. The PM size-segregated samples were subjected to organic analysis by gas chromatography-mass spectrometry (GC-MS), after solvent extraction of filters and an appropriate derivatisation technique. Besides the homologous compound series of organic classes (e.g. n-alkanes, n-alkanols and n-alkanoic acids), special attention was given to the determination of specific molecular markers for different sources (e.g. vehicular). Carbon preference indices (CPI) close to the unity and the presence of PAHs point out vehicle exhaust as the main emission source of the aliphatic and polycyclic aromatic fractions, especially for the roadside aerosols. Concentration ratios between PAHs were also used to assign emission sources. The abundance and the sources of these carcinogenic pollutants are discussed and compared taking into account the local/regional characteristics. Water-soluble ions in PM were also analysed by ionic chromatography. A portion of the same filters was subjected to metal speciation by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) or Instrumental Neutron Activation Analysis (INAA). Receptor-oriented modelling for source apportionment was applied to the size-segregated PM chemical composition data. Results of this work are expected to cover a lack of reliable information for the knowledge of the particle size-dependent constitution, sources and atmospheric formation processes in this area of the central Iberian Peninsula. Acknowledgements: F. Mirante thanks the Portuguese Science Foundation for financial support of the training period at CIEMAT, as well for the PhD grant SFRH/BD/45473/2008. M.A. Revuelta acknowledges the Ministry of Science and Innovation for their economical support through the FPI predoctoral grant BES-2008-007079.

Bioavailability of Polycyclic Aromatic Hydrocarbons and their Potential Application in Eco-risk Assessment and Source Apportionment in Urban River Sediment

PubMed Central

Yang, Xunan; Yu, Liuqian; Chen, Zefang; Xu, Meiying

2016-01-01

Traditional risk assessment and source apportionment of sediments based on bulk polycyclic aromatic hydrocarbons (PAHs) can introduce biases due to unknown aging effects in various sediments. We used a mild solvent (hydroxypropyl-β-cyclodextrin) to extract the bioavailable fraction of PAHs (a-PAHs) from sediment samples collected in Pearl River, southern China. We investigated the potential application of this technique for ecological risk assessments and source apportionment. We found that the distribution of PAHs was associated with human activities and that the a-PAHs accounted for a wide range (4.7%–21.2%) of total-PAHs (t-PAHs), and high risk sites were associated with lower t-PAHs but higher a-PAHs. The correlation between a-PAHs and the sediment toxicity assessed using tubificid worms (r = −0.654, P = 0.021) was greater than that from t-PAH-based risk assessment (r = −0.230, P = 0.472). Moreover, the insignificant correlation between a-PAH content and mPEC-Q of low molecular weight PAHs implied the potiential bias of t-PAH-based risk assessment. The source apportionment from mild extracted fractions was consistent across different indicators and was in accordance with typical pollution sources. Our results suggested that mild extraction-based approaches reduce the potential error from aging effects because the mild extracted PAHs provide a more direct indicator of bioavailability and fresher fractions in sediments. PMID:26976450

[Tracing Sources of Sulfate Aerosol in Nanjing Northern Suburb Using Sulfur and Oxygen Isotopes].

PubMed

Wei, Ying; Guo, Zhao-bing; Ge, Xin; Zhu, Sheng-nan; Jiang, Wen-juan; Shi, Lei; Chen, Shu

2015-04-01

Abstract: To trace the sources of sulfate contributing to atmospheric aerosol, PM2.5 samples for isotopic analysis were collected in Nanjing northern suburb during January 2014. The sulfur and oxygen isotopic compositions of sulfate from these samples were determined by EA-IRMS. Source identification and apportionment were carried out using stable isotopic and chemical evidences, combined with absolute principal component analysis (APCA) method. The Δ34S values of aerosol sulfate ranged from 2.7 per thousand to 6.4 per thousand, with an average of 5.0 per thousand ± 0.9 per thousand, while the Δ18O values ranged from 10.6 per thousand to 16.1 per thousand, with an average of 12.5 per thousand ± 1.37 per thousand. In conjunction with air mass trajectories, the results suggested that aerosol sulfates were controlled by a dominance of local anthropogenic sulfate, followed by the contributions of long-distance transported sulfate. There was a minor effect of some other low-Δ34S valued sulfates, which might be expected from biogenic sources. Absolute principal component analysis results showed that the contributions of anthropogenic sulfate and long-distance transported sulfate were 46.74% and 31.54%, respectively.

Key issues in controlling air pollutants in Dhaka, Bangladesh

NASA Astrophysics Data System (ADS)

Begum, Bilkis A.; Biswas, Swapan K.; Hopke, Philip K.

2011-12-01

Particulate matter (PM) sampling for both coarse and fine fractions was conducted in a semi-residential site (AECD) in Dhaka from February 2005 to December 2006. The samples were analyzed for mass, black carbon (BC), and elemental compositions. The resulting data set were analyzed for sources by Positive Matrix Factorization (EPA-PMF). From previous studies, it is found that, the air quality became worse in the dry winter period compared to the rainy season because of higher particulate matter concentration in the ambient air. Therefore, seasonal source contributions were determined from seasonally segregated data using EPA-PMF modeling so that further policy interventions can be undertaken to improve air quality. From the source apportionment results, it is observed that vehicular emissions and emission from brick kiln are the major contributors to air pollution in Dhaka especially in the dry seasons, while contribution from emissions from metal smelters increases during rainy seasons. The Government of Bangladesh is considering different interventions to reduce the emissions from those sources by adopting conversion of diesel/petrol vehicles to CNG, increasing traffic speed in the city and by introducing green technologies for brick production. However, in order to reduce the transboundary effect it is necessary to take action regionally.

Preliminary analysis of columnar aerosol properties in relation to surface PM measurements in the DAMOCLES 2006 field campaign (Spain)

NASA Astrophysics Data System (ADS)

Estelles, V.; Esteve, A.; Pey, J.; Martinez-Lozano, J. A.; Utrillas, M. P.; Querol, X.; de La Rosa, J.; Gonzalez-Castanedo, Y.; Alastuey, A.; Gangoiti, G.

2009-04-01

The DAMOCLES network is a Spanish thematic network, started in 2004, whose main objective is the establishment of a link among the different groups that perform research on atmospheric aerosols in Spain. Under the DAMOCLES coordination, a field campaign was held in summer 2006 at the INTA installations (El Arenosillo, Huelva) for the intercomparison of different kind of instruments devoted to in - situ and columnar aerosol measurement. During this field campaign, two daily meteorological soundings were carried out at noon and midnight for characterization of the atmospheric condition. A plane was also flown by the National Institute of Aerospace Technology (INTA) to carry airborne sensors for measuring different atmospheric factors: meteorological parameters, ozone with a 2BTech analyzer, and aerosol particle size distributions in the range (0.01-2) microns, by using a PCASP probe. The columnar aerosol properties were measured by seven CIMEL CE318 sun photometers. For in situ aerosol characterization, high volume collectors (DIGITEL and MCV) with DIGITEL for PM10, PM2.5 and PM1 measurement were used, with two cascade impactors for particulate matter measurement in 7 -8 granulometric fractions. For the PM10, PM2.5 and PM1 measurement, quartz fibre filters of 150 mm diameter were adapted. Other in situ deployed instruments were a Scanning Mobility Particle Sizer (SMPS, Model 3936), two Aerodynamic Particle Sizer (APS Model 3321) and one Grimm Spectrometer (Model #190). For characterization of the aerosol scattering at ground level, three integrating nephelometers TSI-3563 were used. For the columnar profiling we deployed five LIDAR instruments. In this study we have related the columnar aerosol measurements retrieved with one CE318 sun photometer to the surface PM measurements, mainly in some interesting situations where nearby pollution sources were influencing the local atmosphere. For the sun photometric analysis, we have applied the EuroSkyRad package (ESR.pack) to the data from the CE318 serial number #430, from the University of Valencia at Burjassot (Spain). This package is a quite new open source package composed of scripts and inversion algorithms for the processing of both Prede POM and Cimel CE318 instruments. The chemical analysis and source apportionment of the PM data was previously presented. Mean levels recorded during the campaign reached 23, 15 and 12 µg m-3 for PM10, PM2.5 and PM1, respectively. These values fell in the usual range of rural background sites of Southern Spain. Two kind of PM episodes were detected: short episodes recorded at midnight to early morning or at midday, coinciding with transitory hours when the land-sea breeze changed and stagnation conditions occurred, with pollution coming from the Huelva area; and a longer PM episode starting on 30th June 2006 and ending at the end of 1st July 2006, probably associated with the mid to long range transport of polluted air masses from Western Iberia and the Gulf of Cadiz.

Emission factors from biomass burning in three types of appliances: fireplace, woodstove and pellet stove

NASA Astrophysics Data System (ADS)

Duarte, Márcio; Vicente, Estela; Calvo, Ana; Nunes, Teresa; Tarelho, Luis; Alves, Célia

2014-05-01

In the last years, the importance of biomass fuels has increased mainly for two reasons. One of them is the effort to control the emissions of greenhouse gases, and on the other hand, the increasing costs associated with fossil fuels. Besides that, biomass burning is now recognised as one of the major sources contributing to high concentrations of particulate matter, especially during winter time. Southern European countries have a lack of information regarding emission profiles from biomass burning. Because of that, in most source apportionment studies, the information used comes from northern and alpine countries, whose combustion appliances, fuels and habits are different from those in Mediterranean countries. Due to this lack of information, series of tests using different types of equipment, as well as fuels, were carried out in order to obtain emission profiles and emission factors that correspond to the reality in southern European countries. Tests involved three types of biomass appliances used in Portugal, a fireplace, a woodstove and a modern pellet stove. Emission factors (mg.kg-1 fuel, dry basis) for CO, THC and PM10 were obtained. CO emission factors ranged from 38, for pine on the woodstove, to 84 for eucalyptus in the fireplace. THC emissions were between 4 and 24, for pine in the woodstove and eucalyptus in the fireplace, respectively. PM10 emission factors were in the range from 3.99, for pine in the woodstove, to 17.3 for eucalyptus in the fireplace. On average, the emission factors obtained for the fireplace are 1.5 (CO) to 4 (THC) times higher than those of the woodstove. The fireplace has emission factors for CO, THC and PM10 10, 35 and 32 times, respectively, higher than the pellet stove.

Seasonal variations of fine particulate organosulfates derived from biogenic and anthropogenic hydrocarbons in the mid-Atlantic United States

NASA Astrophysics Data System (ADS)

Meade, L. Edward; Riva, Matthieu; Blomberg, Max Z.; Brock, Amanda K.; Qualters, Elisa Marie; Siejack, Richard A.; Ramakrishnan, Kumar; Surratt, Jason D.; Kautzman, Kathryn E.

2016-11-01

Organosulfates (OSs) are an important and ubiquitous class of organic compounds found in ambient fine particulate matter (PM2.5) that serves as markers for multiphase chemical processes leading to secondary organic aerosol (SOA) formation. In this study, high-volume filter sampling was implemented to collect PM2.5 samples during the August 2012-June 2013 time period in suburban Towson, MD. By utilizing ultra-performance liquid chromatography coupled with high-resolution quadrupole time-of-flight mass spectrometry employing an electrospray ionization source (UPLC/ESI-HR-QTOFMS), 58 OSs were characterized and quantified in PM2.5 collected across all seasons. The selection of the extraction solvent was also found to be important for OS characterization. Seasonal trends demonstrate that the atmospheric oxidation of biogenic volatile organic compounds (VOCs) dominates OS formation in early fall and spring, with substantial contributions from isoprene OS (∼15 ng/m3), and limonene and α-pinene OS (∼5 ng/m3). From November to March anthropogenic OSs, including polycyclic aromatic hydrocarbon (PAH)- and alkane-derived OSs recently characterized in laboratory-generated SOA, reached their highest levels averaging 4 ng/m3. Nitrogen-containing OSs derived from terpene chemistry remain consistent over the sampling period averaging 2 ng/m3 and do not demonstrate strong seasonal fluctuations. Correlations between the identified OSs and known organic acids that arise from either the atmospheric oxidation of biogenic or anthropogenic VOCs assist in source apportionment. Meteorological data coupled with air mass back-trajectory analyses using HYSPLIT provide insight into meteorological and transport conditions that promote the formation/occurrence of OSs within the mid-Atlantic U.S. region.

Elemental composition and sources of fine and ultrafine ambient particles in Erfurt, Germany.

PubMed

Cyrys, J; Stölzel, M; Heinrich, J; Kreyling, W G; Menzel, N; Wittmaack, K; Tuch, T; Wichmann, H-Erich

2003-04-15

We present the first results of a source apportionment for the urban aerosol in Erfurt, Germany, for the period 1995-1998. The analysis is based on data of particle number concentrations (0.01-2.5 microm; mean 1.8 x 10(4) cm(-3), continuous), the concentration of the ambient gases SO(2), NO, NO(2) and CO (continuous), particle mass less than 2.5 microm (PM(2.5)) and less than 10 microm (PM(10)) (Harvard Impactor sampling, mean PM(2.5) 26.3 micro/m(3), mean PM(10) 38.2 microg/m(3)) and the size fractionated concentrations of 19 elements (impactor sampling 0.05-1.62 microm, PIXE analysis). We determined: (a) the correlations between (i) the 1- and 24-h average concentrations of the gaseous pollutants and the particle number as well as the particle mass concentration and (ii) between the 24-h elemental concentrations; (b) Crustal Enrichment Factors for the PIXE elements using Si as reference element; and (c) the diurnal pattern of the measured pollutants on weekdays and on weekends. The highly correlated PIXE elements Si, Al, Ti and Ca having low enrichment factors were identified as soil elements. The strong correlation of particle number concentrations with NO, which is considered to be typically emitted by traffic, and the striking similarity of their diurnal variation suggest that a sizable fraction of the particle number concentration is associated with emission from vehicles. Besides NO and particle number concentrations other pollutants such as NO(2), CO as well as the elements Zn and Cu were strongly correlated and appear to reflect motor vehicle traffic. Sulfur could be a tracer for coal combustion, however, it was not correlated with any of the quoted elements. Highly correlated elements V and Ni have similar enrichment factors and are considered as tracers for oil combustion.

Measurement of chemical composition and optical properties of PM2.5 at Rudong, China

NASA Astrophysics Data System (ADS)

Taketani, F.; Kanaya, Y.; Pan, X.; Irie, H.; Takashima, H.; Tanimoto, H.; Saito, S.; Akimoto, H.; Wang, Z.

2013-12-01

Intensive field campaign in Rudong(32.26 deg N, 121.37 deg E), located 100 km north of the city center of Shanghai, China, in May and June 2010 was carried out. To investigate chemical and optical property of aerosol particles, in this study, 9 or 14-hours PM2.5 samples were collected on the quartz filters using High-volume(500L/min) samplers. Using these filters, EC (elemental carbon) and OC(organic carbon), water-soluble ions(SO42-, NO3-, NH4+, Cl-, Ca2+, Mg2+, K+, and Na+) and metals(Al, Fe, Cu, Mn, Zn, Pb) were measured by Sunset lab EC/OC instrument, ion-chromatography, and ICP-AES, respectively. Furthermore, to monitor PM2.5 total mass, we employed SHARP monitor. During the campaign, total mass concentration monitored by SHARP instrument ranged from 3.2 to 172.1 ug/m3 with a mean of 55.3 ug/m3, and major components were sulfate, nitrate, and organics. The total mass concentration of PM2.5 monitored by the SHARP instrument was overestimated with sum of observed mass concentrations of each species. By taking into account the water amount in the particles measured by the SHARP instrument using thermodynamics model with the compositions on the filter and measured RH, we found mass closure should be achieved. We also performed particle source apportionment analysis using Positive Matrix Factorization (PMF) to investigate the source categories. Furthermore, scattering coefficient was reconstructed in an empirical manner by summing the contributions from various chemical species, which were calculated by multiplying observed mass concentrations of each species with empirical mass scattering coefficient. The reconstructed scattering coefficient had good correlation with directly measured coefficients by nephelometer at RH < 40%. We found the importance of ammonium sulfate and organics in determining the ambient scattering coefficient.

Exposure of children to air pollution in the industrial zone of Metropolitan Area of Mexico City

NASA Astrophysics Data System (ADS)

Mugica-Alvarez, Violeta; Quintanilla-Vega, Betsabé; De Vizcaya-Ruiz, Andrea; Alvarado-Cruz, Isabel

2016-04-01

An air quality monitoring in three schools located in the most important industrial zone at the Northeast of the Metropolitan Area of Mexico City (MAMC) was conducted in order to determine the exposure of children to toxics contained in PM10. Particles were analyzed for metals, polycyclic aromatic hydrocarbons (PAH), organic and elemental carbon by ICP-AES, GC-MS and TOT (Sunset lab) respectively. Average concentration of PM10 was 108.4±11.6 μg/m3. Most abundant metals were Fe, Zn and Pb with concentrations ranged by 1.1-5.4 μg/m3, 0.3-2 μg/m3, and 0.18-0.63 μg/m3 respectively; the sum of the seventeen PAHs varied from 1.4 to 3.3 ng/m3 where most abundant PAH were indene[1,2,3-c,d]pyrene, benzo[b]fluoranthene, benzo[a]anthracene, chrysene, and benzo[a]pyrene. The sum of the seven carcinogenic PAH contributed in average with the 48% of the total mixture. Carcinogenic potential of PAH were obtained using toxic equivalent factors determined by Nisbet and La Goy which varied from 0.3 to 0.6 ng/ m3 of benzo[a]pyrene equivalent (BAPeq), this value is lower than the standard proposed for the European Community of 1 ng/ m3, but higher than the standard from the United Kingdom of 0.25 ng/ m3. Principal component analysis for source apportionment showed that vehicular and industrial emissions are the main sources of PM in the zone. In general, the concentrations of particles as well as concentration of metals and PAHs are lower than concentrations measured six year before, showing that the established measures have improved the air quality. Nevertheless these PM10 concentrations exceeded frequently the Mexican Standard and children are especially susceptible due to the higher risk to develop diseases if the exposure occurs at early age.

Volatility-resolved source apportionment of primary and secondary organic aerosol over Europe

NASA Astrophysics Data System (ADS)

Skyllakou, Ksakousti; Fountoukis, Christos; Charalampidis, Panagiotis; Pandis, Spyros N.

2017-10-01

A three-dimensional regional chemical transport model (Particulate Matter Comprehensive Air Quality Model with Extensions, PMCAMx) was applied over Europe combined with a source apportionment algorithm, the Particulate Source Apportionment Technology (PSAT), in order to quantify the sources which contribute to the primary and secondary organic aerosol (OA) during different seasons. The PSAT algorithm was first extended to allow the quantification of the sources of OA as a function of volatility. The most significant OA sources during May were biogenic, while during February residential wood combustion and during September wildfires dominated. The contributions of the various sources have strong spatial dependence. Wildfires were significant OA sources (38% of the OA) for Russia during September, but had a much lower impact (5%) in Scandinavia. The above results are in general consistent with the findings of the CARBOSOL project for selected sites in Europe. For remote sites such as Finokalia in Crete, more than 90% of the OA has undergone two or more generations of oxidation for all seasons. This highly processed oxidized OA is predicted to also dominate over much of Europe during the summer and fall. The first generation SOA is predicted to represent 20-30% of the OA in central and northern Europe during these photochemically active periods.

Aerosol source apportionment based on multi-wavelength photoacoustic light absorption measurements: a simulation method for system's optimisation

NASA Astrophysics Data System (ADS)

Simon, Károly; Ajtai, Tibor; Kiss-Albert, Gergely; Utry, Noémi; Pintér, Máté; Szabó, Gábor; Bozóki, Zoltán

2017-04-01

Aerosol source apportionment is currently one of the outstanding challenges for environmental monitoring. In most cases atmospheric aerosol is a heterogeneous mixture as it typically originates from various sources. Consequently, each aerosol type has distinct chemical and physical properties. Contrary to chemical properties, optical absorption and size distribution of airborne particles can be measured in real time with high time resolution i.e. their measurement facilitates real time source apportionment (Favez et al (2009), Ajtai et al (2011), Favez et al (2010)). The wavelength dependency of the optical absorption coefficient (OAC) is usually characterised by the Absorption Angström Exponent (AAE). So far, the selection of light sources (lasers) into a photoacoustic aerosol measuring system was based on rule of thumb type estimations only. Recently, we proposed a simulation method that can be used to estimate the accuracy of aerosol source apportionment in case of a dual wavelength photoacoustic system (Simon et al., (2017)). This simulation is based on the assumption that the atmospheric aerosol load is dominated by two distinct sources and each of them is strongly light absorbing with specific AAE values. This is a typical scenario e.g. for urban measurements under wintry conditions when dominating aerosol sources are fossil fuel and wood burning with characteristic AAE 1 and 2, respectively. The wavelength pair of 405 and 1064 nm was found to be optimal for source apportionment in this case. In the presented study we investigated the situation when there are aerosol components with only slightly different AAE values and searched for a photoacoustic system which is optimal for distinguishing these components. Ajtai, T.; Filep, Á.; Utry, N.; Schnaiter, M.; Linke, C.; Bozóki, Z.; Szabó, G. and Leisner T. (2011) Journal of Aerosol Science 42, 859-866. Favez, O.; Cachier, H.; Sciare, J.; Sarda-Estève, R. and Martinon, L. (2009) Atmospheric Environment 43, 3640-3644. Favez, O.; El Haddad, I.; Piot, C.; Boréave, A.; Abidi, E.; Marchand, N.; Jaffrezo, J. L.; Besombes, J. L.; Personnaz, M. B.; Sciare, J.; Wortham, H.; George, C. and D'Anna, B. (2010), Atmos. Chem. Phys. 10, 5295-5314. Simon, K.A.; Ajtai, T; Gulyas, G; Utry, N; Pinter, M; Szabo, G. and Bozoki, Bozoki, Z. (2017), Journal of Aerosol Science 104, 10-15.

Photochemical Grid Modelling Study to Assess Potential Air Quality Impacts Associated with Energy Development in Colorado and Northern New Mexico.

NASA Astrophysics Data System (ADS)

Parker, L. K.; Morris, R. E.; Zapert, J.; Cook, F.; Koo, B.; Rasmussen, D.; Jung, J.; Grant, J.; Johnson, J.; Shah, T.; Pavlovic, T.

2015-12-01

The Colorado Air Resource Management Modeling Study (CARMMS) was funded by the Bureau of Land Management (BLM) to predict the impacts from future federal and non-federal energy development in Colorado and Northern New Mexico. The study used the Comprehensive Air Quality Model with extensions (CAMx) photochemical grid model (PGM) to quantify potential impacts from energy development from BLM field office planning areas. CAMx source apportionment technology was used to track the impacts from multiple (14) different emissions source regions (i.e. field office areas) within one simulation, as well as to assess the cumulative impact of emissions from all source regions combined. The energy development emissions estimates were for the year 2021 for three different development scenarios: (1) low; (2) high; (3) high with emissions mitigation. Impacts on air quality (AQ) including ozone, PM2.5, PM10, NO2, SO2, and air quality related values (AQRVs) such as atmospheric deposition, regional haze and changes in Acid Neutralizing Capacity (ANC) of lakes were quantified, and compared to establish threshold levels. In this presentation, we present a brief summary of the how the emission scenarios were developed, we compare the emission totals for each scenario, and then focus on the ozone impacts for each scenario to assess: (1). the difference in potential ozone impacts under the different development scenarios and (2). to establish the sensitivity of the ozone impacts to different emissions levels. Region-wide ozone impacts will be presented as well as impacts at specific locations with ozone monitors.

Source apportionment of airborne particulates through receptor modeling: Indian scenario

NASA Astrophysics Data System (ADS)

Banerjee, Tirthankar; Murari, Vishnu; Kumar, Manish; Raju, M. P.

2015-10-01

Airborne particulate chemistry mostly governed by associated sources and apportionment of specific sources is extremely essential to delineate explicit control strategies. The present submission initially deals with the publications (1980s-2010s) of Indian origin which report regional heterogeneities of particulate concentrations with reference to associated species. Such meta-analyses clearly indicate the presence of reservoir of both primary and secondary aerosols in different geographical regions. Further, identification of specific signatory molecules for individual source category was also evaluated in terms of their scientific merit and repeatability. Source signatures mostly resemble international profile while, in selected cases lack appropriateness. In India, source apportionment (SA) of airborne particulates was initiated way back in 1985 through factor analysis, however, principal component analysis (PCA) shares a major proportion of applications (34%) followed by enrichment factor (EF, 27%), chemical mass balance (CMB, 15%) and positive matrix factorization (PMF, 9%). Mainstream SA analyses identify earth crust and road dust resuspensions (traced by Al, Ca, Fe, Na and Mg) as a principal source (6-73%) followed by vehicular emissions (traced by Fe, Cu, Pb, Cr, Ni, Mn, Ba and Zn; 5-65%), industrial emissions (traced by Co, Cr, Zn, V, Ni, Mn, Cd; 0-60%), fuel combustion (traced by K, NH4+, SO4-, As, Te, S, Mn; 4-42%), marine aerosols (traced by Na, Mg, K; 0-15%) and biomass/refuse burning (traced by Cd, V, K, Cr, As, TC, Na, K, NH4+, NO3-, OC; 1-42%). In most of the cases, temporal variations of individual source contribution for a specific geographic region exhibit radical heterogeneity possibly due to unscientific orientation of individual tracers for specific source and well exaggerated by methodological weakness, inappropriate sample size, implications of secondary aerosols and inadequate emission inventories. Conclusively, a number of challenging issues and specific recommendations have been included which need to be considered for a scientific apportionment of particulate sources in different geographical regions of India.

Stable sulfur isotope ratios and chemical compositions of fine aerosols (PM2.5) in Beijing, China.

PubMed

Wei, Lianfang; Yue, Siyao; Zhao, Wanyu; Yang, Wenyi; Zhang, Yingjie; Ren, Lujie; Han, Xiaokun; Guo, Qingjun; Sun, Yele; Wang, Zifa; Fu, Pingqing

2018-08-15

Pervasive particulate pollution has been observed over large areas of the North China Plain. The high level of sulfate, a major component in fine particles, is pronounced during heavy pollution periods. Being different from source apportionments by atmospheric chemistry-transport model and receptor modeling methods, here we utilize sulfur isotopes to discern the potential emission sources. Sixty-five daily PM 2.5 samples were collected at an urban site in Beijing between September 2013 and July 2014. Inorganic ions, organic/elemental carbon and stable sulfur isotopes of sulfate were analyzed. The "fingerprint" characteristics of stable sulfur isotopic composition, together with trajectory clustering modeled by HYSPLIT-4 (HYbrid Single-Particle Lagrangian Integrated Trajectory) and FLEXPART ("FLEXible PARTicle dispersion model"), was employed to identify potential aerosol sources in Beijing. Results exhibited a distinctive seasonality with sulfate, nitrate, ammonium, organic matter, and element carbon being the dominant species of PM 2.5 . Elevated concentrations of chloride with high organic matter were found in autumn and winter as a result of enhanced fossil fuel (mainly coal) combustion. The δ 34 S values of the Beijing aerosols ranged from 2.8‰ to 9.9‰ with an average of 6.0 ± 1.8‰, further indicating that the major sulfur source was direct coal burning emission. Owing to the changing patterns between oxidation pathways of S(IV) in different seasons, δ 34 S values varied with a winter maximum (8.2 ± 1.1‰) and a summer minimum (4.9 ± 1.9‰). The results of trajectory clustering and FLEXPART demonstrated that higher concentrations of sulfate with lower sulfur isotope ratios (4.6 ± 0.8‰) were associated with air masses from the south or east, whereas lower sulfate concentrations with heavier sulfur isotope ratios (6.7 ± 1.6‰) were observed when the air masses were mainly from the north or northwest. These results suggested that the fine aerosol pollution in Beijing, especially sulfate pollution, was mainly due to coal combustion sources from regional and local regions. Copyright © 2018 Elsevier B.V. All rights reserved.

A wintertime study of PM2.5-bound polycyclic aromatic hydrocarbons in Taiyuan during 2009-2013: Assessment of pollution control strategy in a typical basin region

NASA Astrophysics Data System (ADS)

Li, Hongyan; Guo, Lili; Cao, Runfang; Gao, Bo; Yan, Yulong; He, Qiusheng

2016-09-01

Taiyuan city in Shanxi province, China has been one of the top heavily polluted cities in the world for a long time with large industrial emissions and high disease burden. Many pollution control strategies have been implemented forcefully by the government in recent years in Taiyuan. To better understand the effect of the strategies and related influence factors, we studied polycyclic aromatic hydrocarbons (PAHs) in fine particulate matter (PM2.5) during heating seasons in Taiyuan from 2009 to 2013. The results showed that the concentrations of PM2.5 (70.7-477.9 μg/m3) and related total PAHs (T-PAHs, 128.7-1840.2 ng/m3) far exceeded the air quality standards issued by the Ministry of Environmental Protection of China (MEP) and were higher than those in many domestic and foreign cities in spite of the pollution control. Source apportionment by the diagnostic ratio analysis and PMF model found that coal consumption contributed the most (52.1%) to the total PM2.5-bound PAHs followed by the coking industry (27.3%) and traffic exhausts (20.6%). Significant decreases in PM2.5 and PAHs levels were found in 2013, which was probably due to the large abatement of residential coal consumption and favorable meteorological factors. Being located in the north of Taiyuan basin, the pollution in Taiyuan could be aggravated by the regional transport of coal combustion- and coking-related pollutants from other industrial development zones in the south-western basin as found by the analysis of meteorological influence and back trajectory. Although the PAHs were the lowest in 2013, the BaPeq or ILCR were the highest in that year. This should be related to the increasing vehicle numbers in Taiyuan, because vehicle exhaust tends to enrich in higher molecular weight and more toxic PAHs. Our results provided useful guidance for solving the air pollution problem for cities in a semi- or total-closed basin with coal as the major energy source such as Taiyuan.

Assessment of diesel particulate matter exposure in the workplace: freight terminals†

PubMed Central

Sheesley, Rebecca J.; Schauer, James J.; Smith, Thomas J.; Garshick, Eric; Laden, Francine; Marr, Linsey C.; Molina, Luisa T.

2008-01-01

A large study has been undertaken to assess the exposure to diesel exhaust within diesel trucking terminals. A critical component of this assessment is an analysis of the variation in carbonaceous particulate matter (PM) across trucking terminal locations; consistency in the primary sources can be effectively tracked by analyzing trends in elemental carbon (EC) and organic molecular marker concentrations. Ambient samples were collected at yard, dock and repair shop work stations in 7 terminals in the USA and 1 in Mexico. Concentrations of EC ranged from 0.2 to 12 μg m−3 among the terminals, which corresponds to the range seen in the concentration of summed hopanes (0.5 to 20.5 ng m−3). However, when chemical mass balance (CMB) source apportionment results were presented as percent contribution to organic carbon (OC) concentrations, the contribution of mobile sources to OC are similar among the terminals in different cities. The average mobile source percent contribution to OC was 75.3 ± 17.1% for truck repair shops, 65.4 ± 20.4% for the docks and 38.4 ± 9.5% for the terminal yard samples. A relatively consistent mobile source impact was present at all the terminals only when considering percentage of total OC concentrations, not in terms of absolute concentrations. PMID:18392272

Influence of rain on the abundance of bioaerosols in fine and coarse particles

NASA Astrophysics Data System (ADS)

Rathnayake, Chathurika M.; Metwali, Nervana; Jayarathne, Thilina; Kettler, Josh; Huang, Yuefan; Thorne, Peter S.; O'Shaughnessy, Patrick T.; Stone, Elizabeth A.

2017-02-01

Assessing the environmental, health, and climate impacts of bioaerosols requires knowledge of their size and abundance. These two properties were assessed through daily measurements of chemical tracers for pollens (sucrose, fructose, and glucose), fungal spores (mannitol and glucans), and Gram-negative bacterial endotoxins in two particulate matter (PM) size modes: fine particles (< 2.5 µm) and coarse particles (2.5-10 µm) as determined by their aerodynamic diameter. Measurements were made during the spring tree pollen season (mid-April to early May) and late summer ragweed season (late August to early September) in the Midwestern US in 2013. Under dry conditions, pollen, and fungal spore tracers were primarily in coarse PM (> 75 %), as expected for particles greater than 2.5 µm. Rainfall on 2 May corresponded to maximum atmospheric pollen tracer levels and a redistribution of pollen tracers to the fine PM fraction (> 80 %). Both changes were attributed to the osmotic rupture of pollen grains that led to the suspension of fine-sized pollen fragments. Fungal spore tracers peaked in concentration following spring rain events and decreased in particle size, but to a lesser extent than pollens. A short, heavy thunderstorm in late summer corresponded to an increase in endotoxin and glucose levels, with a simultaneous shift to smaller particle sizes. Simultaneous increase in bioaerosol levels and decrease in their size have significant implications for population exposures to bioaerosols, particularly during rain events. Chemical mass balance (CMB) source apportionment modeling and regionally specific pollen profiles were used to apportion PM mass to pollens and fungal spores. Springtime pollen contributions to the mass of particles < 10 µm (PM10) ranged from 0.04 to 0.8 µg m-3 (0.2-38 %, averaging 4 %), with maxima occurring on rainy days. Fungal spore contributions to PM10 mass ranged from 0.1 to 1.5 µg m-3 (0.8-17 %, averaging 5 %), with maxima occurring after rain. Overall, this study defines changes to the fine- and coarse-mode distribution of PM, pollens, fungal spores, and endotoxins in response to rain in the Midwestern United States and advances the ability to apportion PM mass to pollens.

Source apportionment and air quality impact assessment studies in Beijing/China

NASA Astrophysics Data System (ADS)

Suppan, P.; Schrader, S.; Shen, R.; Ling, H.; Schäfer, K.; Norra, S.; Vogel, B.; Wang, Y.

2012-04-01

More than 15 million people in the greater area of Beijing are still suffering from severe air pollution levels caused by sources within the city itself but also from external impacts like severe dust storms and long range advection from the southern and central part of China. Within this context particulate matter (PM) is the major air pollutant in the greater area of Beijing (Garland et al., 2009). PM did not serve only as lead substance for air quality levels and therefore for adverse health impact effects but also for a strong influence on the climate system by changing e.g. the radiative balance. Investigations on emission reductions during the Olympic Summer Games in 2008 have caused a strong reduction on coarser particles (PM10) but not on smaller particles (PM2.5). In order to discriminate the composition of the particulate matter levels, the different behavior of coarser and smaller particles investigations on source attribution, particle characteristics and external impacts on the PM levels of the city of Beijing by measurements and modeling are performed: Examples of long term measurements of PM2.5 filter sampling in 2005 with the objectives of detailed chemical (source attribution, carbon fraction, organic speciation and inorganic composition) and isotopic analyses as well as toxicological assessment in cooperation with several institutions (Karlsruhe Institute of Technology (IfGG/IMG), Helmholtz Zentrum München (HMGU), University Rostock (UR), Chinese University of Mining and Technology Beijing, CUMTB) will be discussed. Further experimental studies include the operation of remote sensing systems to determine continuously the MLH (by a ceilometer) and gaseous air pollutants near the ground (by DOAS systems) as well as at the 320 m measurement tower (adhesive plates at different heights for passive particle collection) in cooperation with the Institute of Atmospheric Physics (IAP) of the Chinese Academy of Sciences (CAS). The influence of the MLH on the air pollution concentration could be demonstrated and will be discussed. The impact of dust storm events on the overall pollution level of particulate matter in the greater area of Beijing is being assessed by the online coupled comprehensive model system COSMO-ART. First results of the dust storm modeling in northern China (2006, April 3rd until 12th) demonstrates very well the general behavior of the meteorological parameters temperature and humidity as well as a good agreement between modeled and measured dust storm concentration variability at Beijing in the course of time. The results show the importance of intertwine investigations of measurements and modeling, the analysis of local air pollution levels as well as the impact and analysis of advective process in the greater region of Beijing. Comprehensive investigations on particulate matter are a prerequisite for the knowledge of the source strengths and source attribution to the overall air pollution level. Only this knowledge can help to formulate and to introduce specific reduction measures to reduce coarser as well as finer particulates.

Integrating Source Apportionment Tracers into a Bottom-up Inventory of Methane Emissions in the Barnett Shale Hydraulic Fracturing Region.

PubMed

Townsend-Small, Amy; Marrero, Josette E; Lyon, David R; Simpson, Isobel J; Meinardi, Simone; Blake, Donald R

2015-07-07

A growing dependence on natural gas for energy may exacerbate emissions of the greenhouse gas methane (CH4). Identifying fingerprints of these emissions is critical to our understanding of potential impacts. Here, we compare stable isotopic and alkane ratio tracers of natural gas, agricultural, and urban CH4 sources in the Barnett Shale hydraulic fracturing region near Fort Worth, Texas. Thermogenic and biogenic sources were compositionally distinct, and emissions from oil wells were enriched in alkanes and isotopically depleted relative to natural gas wells. Emissions from natural gas production varied in δ(13)C and alkane ratio composition, with δD-CH4 representing the most consistent tracer of natural gas sources. We integrated our data into a bottom-up inventory of CH4 for the region, resulting in an inventory of ethane (C2H6) sources for comparison to top-down estimates of CH4 and C2H6 emissions. Methane emissions in the Barnett are a complex mixture of urban, agricultural, and fossil fuel sources, which makes source apportionment challenging. For example, spatial heterogeneity in gas composition and high C2H6/CH4 ratios in emissions from conventional oil production add uncertainty to top-down models of source apportionment. Future top-down studies may benefit from the addition of δD-CH4 to distinguish thermogenic and biogenic sources.

Microbial water pollution: a screening tool for initial catchment-scale assessment and source apportionment.

PubMed

Kay, D; Anthony, S; Crowther, J; Chambers, B J; Nicholson, F A; Chadwick, D; Stapleton, C M; Wyer, M D

2010-11-01

The European Union Water Framework Directive requires that Management Plans are developed for individual River Basin Districts. From the point of view of faecal indicator organisms (FIOs), there is a critical need for screening tools that can provide a rapid assessment of the likely FIO concentrations and fluxes within catchments under base- and high-flow conditions, and of the balance ('source apportionment') between agriculture- and sewage-derived sources. Accordingly, the present paper reports on: (1) the development of preliminary generic models, using water quality and land cover data from previous UK catchment studies for assessing FIO concentrations, fluxes and source apportionment within catchments during the summer bathing season; (2) the calibration of national land use data, against data previously used in the models; and (3) provisional FIO concentration and source-apportionment assessments for England and Wales. The models clearly highlighted the crucial importance of high-flow conditions for the flux of FIOs within catchments. At high flow, improved grassland (and associated livestock) was the key FIO source; FIO loadings derived from catchments with high proportions of improved grassland were shown to be as high as from urbanized catchments; and in many rural catchments, especially in NW and SW England and Wales, which are important areas of lowland livestock (especially dairy) farming, ≥ 40% of FIOs was assessed to be derived from agricultural sources. In contrast, under base-flow conditions, when there was little or no runoff from agricultural land, urban (i.e. sewerage-related) sources were assessed to dominate, and even in rural areas the majority of FIOs were attributed to urban sources. The results of the study demonstrate the potential of this type of approach, particularly in light of climate change and the likelihood of more high-flow events, in underpinning informed policy development and prioritization of investment. Copyright © 2009 Elsevier B.V. All rights reserved.

Sediment source apportionment in Laurel Hill Creek, PA, using Bayesian chemical mass balance and isotope fingerprinting

USGS Publications Warehouse

Stewart, Heather; Massoudieh, Arash; Gellis, Allen C.

2015-01-01

A Bayesian chemical mass balance (CMB) approach was used to assess the contribution of potential sources for fluvial samples from Laurel Hill Creek in southwest Pennsylvania. The Bayesian approach provides joint probability density functions of the sources' contributions considering the uncertainties due to source and fluvial sample heterogeneity and measurement error. Both elemental profiles of sources and fluvial samples and 13C and 15N isotopes were used for source apportionment. The sources considered include stream bank erosion, forest, roads and agriculture (pasture and cropland). Agriculture was found to have the largest contribution, followed by stream bank erosion. Also, road erosion was found to have a significant contribution in three of the samples collected during lower-intensity rain events. The source apportionment was performed with and without isotopes. The results were largely consistent; however, the use of isotopes was found to slightly increase the uncertainty in most of the cases. The correlation analysis between the contributions of sources shows strong correlations between stream bank and agriculture, whereas roads and forest seem to be less correlated to other sources. Thus, the method was better able to estimate road and forest contributions independently. The hypothesis that the contributions of sources are not seasonally changing was tested by assuming that all ten fluvial samples had the same source contributions. This hypothesis was rejected, demonstrating a significant seasonal variation in the sources of sediments in the stream.

Spatial-temporal variations, sources, and transport of airborne inhalable metals (PM10) in urban and rural areas of northern China

NASA Astrophysics Data System (ADS)

Luo, X. S.; Ip, C. C. M.; Li, W.; Tao, S.; Li, X. D.

2014-05-01

Atmospheric particle pollution is a serious environmental issue in China, especially the northern regions. Ambient air loadings (ng m-3), pollution sources and apportionment, and transport pathways of trace (Cd, Co, Cu, Ni, Pb, V, and Zn) and major (Al, Ca, Fe, and Mg) metals associated with inhalable particulate matters (PM10 aerosols) were characterized in urban, rural village, and rural field areas of seven cities (from inland in the west to the coast in the east: Wuwei, Yinchuan, Taiyuan, Beijing, Dezhou, Yantai, and Dalian) across northern China by taking one 72 h sample each site within a month for a whole year (April 2010 to March 2011). Ambient PM10 pollution in northern China is especially significant in the cold season (October-March) due to the combustion of coal for heating and dust storms in the winter and spring. Owing to variations in emission intensity and meteorological conditions, there is a trend of decrease in PM10 levels in cities from west to east. Both air PM10 and the associated metal loadings for urban and rural areas were comparable, showing that the current pattern of regional pollution in China differs from the decreasing urban-rural-background transect that is usual in other parts of the world. The average metal levels are Zn (276 ng m-3) ≫ Pb (93.7) ≫ Cu (54.9) ≫ Ni (9.37) > V (8.34) ≫ Cd (2.84) > Co (1.76). Judging from concentrations (mg kg-1), enrichment factors (EFs), a multivariate statistical analysis (principal component analysis, PCA), and a receptor model (absolute principal component scores-multiple linear regression analysis, APCS-MLR), the airborne trace metals (Zn, Pb, Cu, and Cd) in northern China were mainly anthropogenic, and mostly attributable to coal combustion and vehicle emissions with additional industrial sources. However, the Co was mostly of crustal origin, and the V and Ni were mainly from soil/dust in the western region and mostly from the petrochemical industry/oil combustion in the east. The accumulation of typical "urban metals" (Pb, Zn, Cd, and Cu) showed a trend of increase from west to east, indicating their higher anthropogenic contribution in eastern cities. The winter northwestern monsoon and westerly jet stream were the dominant forces in the long-range transport of airborne PM metals in northern China, with potentially global implications.

Chemical composition and source apportionment of PM2.5 during heavy pollution episodes in 2013-2015 in Handan, China

NASA Astrophysics Data System (ADS)

Ma, X.; Wang, L.; Tan, J.; Meng, C.; Zhang, F.; Ma, S.; Wei, Z.; Zhang, C.; Zhao, L.; Ji, S.

2017-12-01

To investigate the formation mechanism of heavy air pollution in Handan, China, a comprehensive dataset including continuous online hourly observations of the meteorological parameters and air pollutants, i.e., SO2 NO, NO2, NOx, CO, O3, in January, 2013-2015, as well as water-soluble inorganic ions (WSII) (NO3-, SO42-, NH4+, Cl-, Na+, Mg2+, K+, Ca2+), carbon components (OC, EC) and inorganic elements in PM2.5 are analyzed in this study. The HYSPLIT Trajectory Model is applied to analyze the transport pathway of air mass. NO, SO2 and PM2.5 showed an obvious decreasing trend. Compared with 2013, NO, SO2 and PM2.5 decreased by 12.1%, 25.5%, 7.6% and 12.5%, 33.5%, 30.9% in 2014 and 2015, respectively. Heavy pollution episodes were often observed in winter during this period. A severe pollution episode was occurred from 2 to 20 January 2013. The peak concentrations of PM2.5 and PM10 were 1144.3 μg/m3 and 780.2 μg/m3 on 11 January 2013, respectively. The polluted level of heavy pollution episodes in 2014 and 2015 were slighter than 2013, but still can't be ignored. Their durations were short and generally lasted about 4-7 days, however, the frequency of occurrence was increased. Low temperature and wind speed and high humidity were always observed during these pollution episodes. The concentrations of chemical compositions of PM2.5 during heavy pollution episodes were significantly higher than those in clean day. The concentrations of SNA (SO42-, NO3- and NH4+) and OC peaked at 12 January 2013, 16 January 2014 and 15 January 2015, respectively, which is consistent with the previous analysis. The average monthly concentrations of SO42- and NH4+ were in the order of: 2013>2014>2015, indicating that this was related to the decrease of SO2 concentration. Cu, Zn, Pb were highly enriched elements, indicating the industrial pollution, especially from iron and steel smelting had a significant contribution to PM2.5 in Handan. Additionally, Cr in 2015, Mn, Co in 2014 and 2015 were highly enriched elements, respectively. Finally, the major spatial sources of pollutants in Handan are local emissions and from Hebei Province. The short-distance trajectories in January accounted for 63%, 64%, 50%, respectively.

Relative Impact of Emissions Controls and Meteorology on Air Pollution Mitigation Associated with the Asia-Pacific Economic Cooperation (APEC) Conference in Beijing, China

NASA Astrophysics Data System (ADS)

Zhang, Y.; Wang, Y.; Schauer, J. J.; de Foy, B.

2016-12-01

The Beijing government and its surrounding provinces implemented a series of measures to ensure haze-free skies during the 22nd Asia-Pacific Economic Cooperation (APEC) conference (November 10th - 11th, 2014). These measures included restrictions on traffic, construction, and industrial activity. Twelve hour measurements of the concentration and composition of ambient fine particulate matter (PM2.5) were performed for 5 consecutive months near the APEC conference site before (September 11th - November 2nd, 2014), during (November 3rd - 12th, 2014) and after (November 13th, 2014 - January 31st, 2015). The measurements are used in a positive matrix factorization model to determine the contributions from seven sources of PM2.5: secondary aerosols, mobile source, industrial emission, road dust, soil dust, biomass burning and residual oil combustion. The source apportionment results are integrated with backward trajectory analysis using Weather Research and Forecast (WRF) meteorological simulations, which determine the relative influence of new regulation and meteorology upon improved air quality during the APEC conference. Data show that controls are very effective, but meteorology must be taken into account to determine the actual influence of the controls on pollution reduction. The Industry source control is the most effective for reducing concentrations, follows by secondary aerosol and biomass controls, while the least effective control is for the residual oil combustion source. The largest reductions in concentrations occur when air mass transport is from the west-northwest (Ulanqab). Secondary aerosol and mobile source reductions are most significant for air mass transport from the north-northwest (Xilingele League) origin, and least significant for northeast transport (Chifeng via Tangshan conditions). The largest reductions of soil dust, biomass burning, and industrial source are distinctly seen for Ulanqab conditions and least distinct for Xilingele League.

Contributions and source identification of biogenic and anthropogenic hydrocarbons to secondary organic aerosols at Mt. Tai in 2014.

PubMed

Zhu, Yanhong; Yang, Lingxiao; Kawamura, Kimitaka; Chen, Jianmin; Ono, Kaori; Wang, Xinfeng; Xue, Likun; Wang, Wenxing

2017-01-01

Ambient fine particulate matter (PM 2.5 ) and volatile organic compounds (VOCs) collected at Mt. Tai in summer 2014 were analysed and the data were used to identify the contribution of biogenic and anthropogenic hydrocarbons to secondary organic aerosols (SOA) and their sources and potential source areas in high mountain regions. Compared with those in 2006, the 2014 anthropogenic SOA tracers in PM 2.5 aerosols and VOC species related to vehicular emissions exhibited higher concentrations, whereas the levels of biogenic SOA tracers were lower, possibly due to decreased biomass burning. Using the SOA tracer and parameterisation method, we estimated the contributions from biogenic and anthropogenic VOCs, respectively. The results showed that the average concentration of biogenic SOA was 1.08 ± 0.51 μg m -3 , among which isoprene SOA tracers were dominant. The anthropogenic VOC-derived SOA were 7.03 ± 1.21 μg m -3 and 1.92 ± 1.34 μg m -3 under low- and high-NO x conditions, respectively, and aromatics made the greatest contribution. However, the sum of biogenic and anthropogenic SOA only contributed 18.1-49.1% of the total SOA. Source apportionment by positive matrix factorisation (PMF) revealed that secondary oxidation and biomass burning were the major sources of biogenic SOA tracers. Anthropogenic aromatics mainly came from solvent use, fuel and plastics combustion and vehicular emissions. However, for > C6 alkanes and cycloalkanes, vehicular emissions and fuel and plastics combustion were the most important contributors. The potential source contribution function (PSCF) identified the Bohai Sea Region (BSR) as the major source area for organic aerosol compounds and VOC species at Mt. Tai. Copyright © 2016 Elsevier Ltd. All rights reserved.

Verifying Sediment Fingerprinting Results with Known Mixtures

NASA Astrophysics Data System (ADS)

Gellis, A.; Gorman-Sanisaca, L.; Cashman, M. J.

2017-12-01

Sediment fingerprinting is a widely used approach to determine the specific sources of fluvial sediment within a watershed. It relies on the principle that potential sediment sources can be identified using a set of chemical tracers (or fingerprints), and comparison of these source fingerprints with fluvial (target) sediment allows for source apportionment of the fluvial sediment. There are numerous source classifications, fingerprints, and statistical approaches used in the literature to apportion sources of sediment. However, few of these studies have sought to test the method by creating controls on the ratio of sources in the target sediment. Without a controlled environment for inputs and outputs, such verification of results is ambiguous. Here, we generated artificial mixtures of source sediment from an agricultural/forested watershed in Virginia, USA (Smith Creek, 246 km2) to verify the apportionment results. Target samples were established from known mixtures of the four major sediment sources in the watershed (forest, pasture, cropland, and streambanks). The target samples were sieved to less than 63 microns and analyzed for elemental and isotopic chemistry. The target samples and source samples were run through the Sediment Source Assessment Tool (Sed_SAT) to verify if the statistical operations provided the correct apportionment. Sed_SAT uses a multivariate parametric approach to identify the minimum suite of fingerprints that discriminate the source areas and applies these fingerprints through an unmixng model to apportion sediment. The results of this sediment fingerprinting verification experiment will be presented in this session.

Study of polycyclic aromatic hydrocarbons in atmospheric particulate matter of an urban area with iron and steel mills.

PubMed

Menezes, Helvécio C; Cardeal, Zenilda L

2012-07-01

Polycyclic aromatic hydrocarbons (PAHs) were analyzed from ambient air particulate matter <10 µm (PM(10) ) and the total suspended particulate (TSP) phase continuously for a period of six months (May-October 2010) at five sampling sites located in the urban area of Divinópolis (Minas Gerais), southeastern Brazil, near iron and steel mills. The carcinogenic potency of priority PAHs relative to benzo[a]pyrene was estimated for a period of six months. Benzo[a]pyrene equivalents were 7.52 ng/m(3) for the study period. The estimated risk of lifetime lung cancer was 6.5 × 10(-4) . A model based on the diagnostic ratio and principal component analysis was applied for source apportionment. Considering the entire study period, the burning of biomass and fuel oil accounted for about 70% of the PAH profile. An inventory was performed during the monitoring period, with 37 companies representing major industries located in the urban area. The observations were consistent with the distribution of sources and indicated that the iron and steel sector was the largest contributor. Copyright © 2012 SETAC.

The CSSIAR v.1.00 Software: A new tool based on SIAR to assess soil redistribution using Compound Specific Stable Isotopes

NASA Astrophysics Data System (ADS)

Sergio, de los Santos-Villalobos; Claudio, Bravo-Linares; dos Anjos Roberto, Meigikos; Renan, Cardoso; Max, Gibbs; Andrew, Swales; Lionel, Mabit; Gerd, Dercon

Soil erosion is one of the biggest challenges for food production around the world. Many techniques have been used to evaluate and mitigate soil degradation. Nowadays isotopic techniques are becoming a powerful tool to assess soil apportionment. One of the innovative techniques used is the Compound Specific Stable Isotopes (CSSI) analysis, which has been used to track down sediments and specify their sources by the isotopic signature of δ13 C in specific fatty acids. The application of this technique on soil apportionment has been recently developed, however there is a lack of user-friendly Software for data processing and interpretation. The aim of this article is to introduce a new open source tool for working with data sets generated by the use of the CSSI technique to assess soil apportionment, called the CSSIARv1.00 Software

Carbonaceous aerosols emitted from light-duty vehicles operating on gasoline and ethanol fuel blends.

PubMed

Hays, Michael D; Preston, William; George, Barbara J; Schmid, Judy; Baldauf, Richard; Snow, Richard; Robinson, James R; Long, Thomas; Faircloth, James

2013-12-17

This study examines the chemical properties of carbonaceous aerosols emitted from three light-duty gasoline vehicles (LDVs) operating on gasoline (e0) and ethanol-gasoline fuel blends (e10 and e85). Vehicle road load simulations were performed on a chassis dynamometer using the three-phase LA-92 unified driving cycle (UDC). Effects of LDV operating conditions and ambient temperature (-7 and 24 °C) on particle-phase semivolatile organic compounds (SVOCs) and organic and elemental carbon (OC and EC) emissions were investigated. SVOC concentrations and OC and EC fractions were determined with thermal extraction-gas chromatography-mass spectrometry (TE-GC-MS) and thermal-optical analysis (TOA), respectively. LDV aerosol emissions were predominantly carbonaceous, and EC/PM (w/w) decreased linearly with increasing fuel ethanol content. TE-GC-MS analysis accounted for up to 4% of the fine particle (PM2.5) mass, showing the UDC phase-integrated sum of identified SVOC emissions ranging from 0.703 μg km(-1) to 18.8 μg km(-1). Generally, higher SVOC emissions were associated with low temperature (-7 °C) and engine ignition; mixed regression models suggest these emissions rate differences are significant. Use of e85 significantly reduced the emissions of lower molecular weight PAH. However, a reduction in higher molecular weight PAH entities in PM was not observed. Individual SVOC emissions from the Tier 2 LDVs and fuel technologies tested are substantially lower and distributed differently than those values populating the United States emissions inventories currently. Hence, this study is likely to influence future apportionment, climate, and air quality model predictions that rely on source combustion measurements of SVOCs in PM.

AQMEII3 evaluation of regional NA/EU simulations and ...

EPA Pesticide Factsheets

Through the comparison of several regional-scale chemistry transport modelling systems that simulate meteorology and air quality over the European and American continents, this study aims at i) apportioning the error to the responsible processes using time-scale analysis, ii) helping to detect causes of models error, and iii) identifying the processes and scales most urgently requiring dedicated investigations. The analysis is conducted within the framework of the third phase of the Air Quality Model Evaluation International Initiative (AQMEII) and tackles model performance gauging through measurement-to-model comparison, error decomposition and time series analysis of the models biases for several fields (ozone, CO, SO2, NO, NO2, PM10, PM2.5, wind speed, and temperature). The operational metrics (magnitude of the error, sign of the bias, associativity) provide an overall sense of model strengths and deficiencies, while apportioning the error to its constituent parts (bias, variance and covariance) can help to assess the nature and quality of the error. Each of the error components is analysed independently and apportioned to specific processes based on the corresponding timescale (long scale, synoptic, diurnal, and intra-day) using the error apportionment technique devised in the former phases of AQMEII. The application of the error apportionment method to the AQMEII Phase 3 simulations provides several key insights. In addition to reaffirming the strong impac

[Reconstructed ambient light extinction coefficient and its contribution factors in Beijing in January, 2010].

PubMed

Zhu, Li-Hua; Tao, Jun; Chen, Zhong-Ming; Zhao, Yue; Zhang, Ren-Jian; Cao, Jun-Ji

2012-01-01

Aerosol samples for PM2.5 were collected from 1st January to 31st January 2010, in Beijing. The concentrations of organic carbon, elemental carbon, water-solubile ions and soil elements of all particle samples were determined by thermal/optical carbon analyzer, ion chromatography and X-ray fluorescence spectrometer, respectively. The scattering coefficients (b(sp)), absorbing coefficients (b(ap)) and meteorological parameters for this period were also measured. Ambient light extinction coefficients were reconstructed by IMPROVE formula and were compared with measured light extinction coefficients. The results showed that the average mass concentration of PM2.5 was (144.3 +/- 89.1) microg x m(-3) during campaigning period. The average values of measured b(ap), b(sp) and extinction coefficient (b(ext)) were (67.4 +/- 54.3), (328.5 +/- 353.8) and (395.9 +/- 405.2) Mm(-1), respectively. IMPROVE formula is suitable for source apportionment of light extinction coefficient in campaign period. The average value of calculated b'(ext) was (611 +/- 503) Mm(-1) in January, 2010. The major contributors to ambient light extinction coefficients included (NH4) 2SO4 (24.6%), NH4NO3 (11.6%), OM (45.5%), EC (11.9%) and FS (6.4%), respectively.

Chemical composition, sources and secondary processes of aerosols in Baoji city of northwest China

NASA Astrophysics Data System (ADS)

Wang, Y. C.; Huang, R.-J.; Ni, H. Y.; Chen, Y.; Wang, Q. Y.; Li, G. H.; Tie, X. X.; Shen, Z. X.; Huang, Y.; Liu, S. X.; Dong, W. M.; Xue, P.; Fröhlich, R.; Canonaco, F.; Elser, M.; Daellenbach, K. R.; Bozzetti, C.; El Haddad, I.; Prévôt, A. S. H.; Canagaratna, M. R.; Worsnop, D. R.; Cao, J. J.

2017-06-01

Particulate air pollution is a severe environmental problem in China, affecting visibility, air quality, climate and human health. However, previous studies focus mainly on large cities such as Beijing, Shanghai, and Guangzhou. In this study, an Aerodyne Aerosol Chemical Speciation Monitor was deployed in Baoji, a middle size inland city in northwest China from 26 February to 27 March 2014. The non-refractory submicron aerosol (NR-PM1) was dominated by organics (55%), followed by sulfate (16%), nitrate (15%), ammonium (11%) and chloride (3%). A source apportionment of the organic aerosol (OA) was performed with the Sofi (Source Finder) interface of ME-2 (Multilinear Engine), and six main sources/factors were identified and classified as hydrocarbon-like OA (HOA), cooking OA (COA), biomass burning OA (BBOA), coal combustion OA (CCOA), less oxidized oxygenated OA (LO-OOA) and more oxidized oxygenated OA (MO-OOA), which contributed 20%, 14%, 13%, 9%, 23% and 21% of total OA, respectively. The contribution of secondary components shows increasing trends from clean days to polluted days, indicating the importance of secondary aerosol formation processes in driving particulate air pollution. The formation of LO-OOA and MO-OOA is mainly driven by photochemical reactions, but significantly influenced by aqueous-phase chemistry during periods of low atmospheric oxidative capacity.

Contamination source apportionment and health risk assessment of heavy metals in soil around municipal solid waste incinerator: A case study in North China.

PubMed

Ma, Wenchao; Tai, Lingyu; Qiao, Zhi; Zhong, Lei; Wang, Zhen; Fu, Kaixuan; Chen, Guanyi

2018-08-01

Few studies have comprehensively taken into account the source apportionment and human health risk of soil heavy metals in the vicinity of municipal solid waste incinerator (MSWI) in high population density area. In this study, 8 elements (Cr, Pb, Cu, Ni, Zn, Cd, Hg, and As) in fly ash, soil samples from different functional areas and vegetables collected surrounding the MSWI in North China were determined. The single pollution index, integrated Nemerow pollution index, principal component analysis (PCA), absolute principle component score-multiple linear regression (APCS-MLR) model and dose-response model were used in this study. The results showed that the soils around the MSWI were moderately polluted by Cu, Pb, Zn, and Hg, and heavily polluted by As and Cd. MSWI had a significant influence on the distribution of soil heavy metals in different distances from MSWI. The source apportionment results showed that MSWI, natural source, industrial discharges and coal combustion were the four major potential sources for heavy metals in the soils, with the contributions of 36.08%, 29.57%, 10.07%, and 4.55%, respectively. MSWI had a major impact on Zn, Cu, Pb, Cd, and Hg contamination in soil. The non-carcinogenic risk and carcinogenic risk posed by soil heavy metals surrounding the MSWI were unacceptable. The soil heavy metals concentrations and health risks in different functional areas were distinct. MSWI was the predominate source of non-carcinogenic risk with the average contribution rate of 36.99% and carcinogenic risk to adult male, adult female and children with 4.23×10 -4 , 4.57×10 -4 , and 1.41×10 -4 respectively, implying that the impact of MSWI on human health was apparent. This study provided a new insight for the source apportionment and health risk assessment of soil heavy metals in the vicinity of MSWI. Copyright © 2018. Published by Elsevier B.V.

Temporal trend and source apportionment of water pollution in different functional zones of Qiantang River, China.

PubMed

Su, Shiliang; Li, Dan; Zhang, Qi; Xiao, Rui; Huang, Fang; Wu, Jiaping

2011-02-01

The increasingly serious river water pollution in developing countries poses great threat to environmental health and human welfare. The assignment of river function to specific uses, known as zoning, is a useful tool to reveal variations of water environmental adaptability to human impact. Therefore, characterizing the temporal trend and identifying responsible pollution sources in different functional zones could greatly improve our knowledge about human impacts on the river water environment. The aim of this study is to obtain a deeper understanding of temporal trends and sources of water pollution in different functional zones with a case study of the Qiantang River, China. Measurement data were obtained and pretreated for 13 variables from 41 monitoring sites in four categories of functional zones during the period 1996-2004. An exploratory approach, which combines smoothing and non-parametric statistical tests, was applied to characterize trends of four significant parameters (permanganate index, ammonia nitrogen, total cadmium and fluoride) accounting for differences among different functional zones identified by discriminant analysis. Aided by GIS, yearly pollution index (PI) for each monitoring site was further mapped to compare the within-group variations in temporal dynamics for different functional zones. Rotated principal component analysis and receptor model (absolute principle component score-multiple linear regression, APCS-MLR) revealed that potential pollution sources and their corresponding contributions varied among the four functional zones. Variations of APCS values for each site of one functional zone as well as their annual average values highlighted the uncertainties associated with cross space-time effects in source apportionment. All these results reinforce the notion that the concept of zoning should be taken seriously in water pollution control. Being applicable to other rivers, the framework of management-oriented source apportionment is thus believed to have potentials to offer new insights into water management and advance the source apportionment framework as an operational basis for national and local governments. © 2010 Elsevier Ltd. All rights reserved.

Countering Air and Missile Threats

DTIC Science & Technology

2012-03-23

information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources , gathering... apportionment guidance by the JFC. Functional component commands serve to ease the burden on the theater and joint task force staffs, free the JFC to focus...action (COA) to attain the desired objectives. Counterair requires a combination of OCA and DCA operations based on the JFC’s air apportionment

Source Apportionment of Elemental Carbon in Beijing, China: Insights from Radiocarbon and Organic Marker Measurements.

PubMed

Zhang, Yan-Lin; Schnelle-Kreis, Jürgen; Abbaszade, Gülcin; Zimmermann, Ralf; Zotter, Peter; Shen, Rong-rong; Schäfer, Klaus; Shao, Longyi; Prévôt, André S H; Szidat, Sönke

2015-07-21

Elemental carbon (EC) or black carbon (BC) in the atmosphere has a strong influence on both climate and human health. In this study, radiocarbon ((14)C) based source apportionment is used to distinguish between fossil fuel and biomass burning sources of EC isolated from aerosol filter samples collected in Beijing from June 2010 to May 2011. The (14)C results demonstrate that EC is consistently dominated by fossil-fuel combustion throughout the whole year with a mean contribution of 79% ± 6% (ranging from 70% to 91%), though EC has a higher mean and peak concentrations in the cold season. The seasonal molecular pattern of hopanes (i.e., a class of organic markers mainly emitted during the combustion of different fossil fuels) indicates that traffic-related emissions are the most important fossil source in the warm period and coal combustion emissions are significantly increased in the cold season. By combining (14)C based source apportionment results and picene (i.e., an organic marker for coal emissions) concentrations, relative contributions from coal (mainly from residential bituminous coal) and vehicle to EC in the cold period were estimated as 25 ± 4% and 50 ± 7%, respectively, whereas the coal combustion contribution was negligible or very small in the warm period.

Long-term chemical analysis and organic aerosol source apportionment at nine sites in central Europe: source identification and uncertainty assessment

NASA Astrophysics Data System (ADS)

Daellenbach, Kaspar R.; Stefenelli, Giulia; Bozzetti, Carlo; Vlachou, Athanasia; Fermo, Paola; Gonzalez, Raquel; Piazzalunga, Andrea; Colombi, Cristina; Canonaco, Francesco; Hueglin, Christoph; Kasper-Giebl, Anne; Jaffrezo, Jean-Luc; Bianchi, Federico; Slowik, Jay G.; Baltensperger, Urs; El-Haddad, Imad; Prévôt, André S. H.

2017-11-01

Long-term monitoring of organic aerosol is important for epidemiological studies, validation of atmospheric models, and air quality management. In this study, we apply a recently developed filter-based offline methodology using an aerosol mass spectrometer (AMS) to investigate the regional and seasonal differences of contributing organic aerosol sources. We present offline AMS measurements for particulate matter smaller than 10 µm at nine stations in central Europe with different exposure characteristics for the entire year of 2013 (819 samples). The focus of this study is a detailed source apportionment analysis (using positive matrix factorization, PMF) including in-depth assessment of the related uncertainties. Primary organic aerosol (POA) is separated in three components: hydrocarbon-like OA related to traffic emissions (HOA), cooking OA (COA), and biomass burning OA (BBOA). We observe enhanced production of secondary organic aerosol (SOA) in summer, following the increase in biogenic emissions with temperature (summer oxygenated OA, SOOA). In addition, a SOA component was extracted that correlated with an anthropogenic secondary inorganic species that is dominant in winter (winter oxygenated OA, WOOA). A factor (sulfur-containing organic, SC-OA) explaining sulfur-containing fragments (CH3SO2+), which has an event-driven temporal behaviour, was also identified. The relative yearly average factor contributions range from 4 to 14 % for HOA, from 3 to 11 % for COA, from 11 to 59 % for BBOA, from 5 to 23 % for SC-OA, from 14 to 27 % for WOOA, and from 15 to 38 % for SOOA. The uncertainty of the relative average factor contribution lies between 2 and 12 % of OA. At the sites north of the alpine crest, the sum of HOA, COA, and BBOA (POA) contributes less to OA (POA / OA = 0.3) than at the southern alpine valley sites (0.6). BBOA is the main contributor to POA with 87 % in alpine valleys and 42 % north of the alpine crest. Furthermore, the influence of primary biological particles (PBOAs), not resolved by PMF, is estimated and could contribute significantly to OA in PM10.

Diurnal and seasonal trends and source apportionment of redox-active metals in Los Angeles using a novel online metal monitor and Positive Matrix Factorization (PMF)

NASA Astrophysics Data System (ADS)

Mousavi, Amirhosein; Sowlat, Mohammad H.; Sioutas, Constantinos

2018-02-01

In the present study, we identified the sources of four redox-active metals, including Iron (Fe), Chromium (Cr), Cupper (Cu), and Manganese (Mn) and quantified the contribution of these sources to PM2.5 concentrations in central Los Angeles, California, by employing time-resolved measurements (i.e., a time resolution of 2 h) with a recently developed online metal monitor and Positive Matrix Factorization (PMF). Size distribution of ambient PM (14 nm-10 μm) was measured using the Scanning Mobility Particle Sizer (SMPS) and Optical Particle Sizer (OPS). Auxiliary variables were also collected, including elemental (EC) and organic carbon (OC), gaseous pollutants (NO2 and O3), meteorological parameters (including relative humidity (RH) and temperature), and traffic data (for heavy- (HDVs) and light-duty vehicles (LDVs)). A 4-factor solution was found to be optimum for the chemically-speciated dataset, whereas a 5-factor solution appeared to be most plausible for the size distribution data. The factors included fresh traffic, soil/road dust, urban background aerosol, secondary aerosol, and nucleation (only resolved for the size distribution data). Fresh traffic was the major contributor to Fe and Cu concentrations, whereas Cr was mostly found in the urban background aerosol (reflecting a mixture of small local sources as well as aged traffic emissions), and Mn mostly came from both soil/road dust and was to a lesser degree found in urban background aerosol. Secondary aerosol did not contribute to the concentrations of any of these metals, but was associated with very high loading of OC, as expected. Even though the urban background aerosol and secondary aerosol appeared to be characterized by "aged" particles and have a rather homogeneous spatial distribution, the reactions and processes involved in their formation are entirely different. Our results provide insights into the sources of redox-active metals in central Los Angeles. They also underscore the benefits of novel measurement techniques for PM-bound metals, which could enhance our understanding of the sources of atmospheric aerosols by providing us with measurements with finer time resolutions that otherwise would not have been possible using traditional filter-based measurement techniques.

Variation of polycyclic aromatic hydrocarbons in atmospheric PM2.5 during winter haze period around 2014 Chinese Spring Festival at Nanjing: Insights of source changes, air mass direction and firework particle injection.

PubMed

Kong, Shaofei; Li, Xuxu; Li, Li; Yin, Yan; Chen, Kui; Yuan, Liang; Zhang, Yingjie; Shan, Yunpeng; Ji, Yaqin

2015-07-01

Daily PM2.5 samples were collected at a suburban site of Nanjing around 2014 Chinese Spring Festival (SF) and analyzed for 18 kinds of polycyclic aromatic hydrocarbons (PAHs) by GC-MS. Comparison of PAH concentrations during different periods, with different air mass origins and under different pollution situations was done. Sources were analyzed by diagnostics ratios and principal component analysis (PCA). The threat of PAHs was assessed by BaP equivalent concentrations (BaPeq) and incremental lifetime cancer risk (ILCR). The averaged PAHs for pre-SF, SF and after SF periods were 50.6, 17.2 and 29 ng m(-3), indicating the variations of PAH sources, with reduced traffic, industrial and construction activities during SF and gradually re-starting of them after-SF. According to PAH mass concentrations, their relative abundance to particles, ratio of PAHs (3-ring+4-ring)/PAHs(5-ring+6-ring), mass concentrations of combustion-derived and carcinogenic PAHs, fireworks burning is an important source for PAHs during SF. The ILCR values for Chinese New Year day were 0.68 and 3.3 per 100,000 exposed children and adults. It suggested the necessity of controlling fireworks burning during Chinese SF period which was always companied with serious regional haze pollution. PAH concentrations exhibited decreasing trend when air masses coming from the following directions as North China Plain (63.9 ng m(-3))>Central China (53.0 ng m(-3))>Shandong Peninsula (46.6 ng m(-3))>Northwest China (18.8 ng m(-3))>Sea (15.8 ng m(-3)). For different pollution situations, they decreased as haze (44.5 ng m(-3))>fog-haze (28.4 ng m(-3))>clear (12.2 ng m(-3))>fog day (9.2 ng m(-3)). Coal combustion, traffic emission, industrial processes and petroleum (only for non-SF holiday periodss) were the main sources of PM2.5 associated PAHs. Fireworks burning contributed 14.0% of PAHs during SF period. Directly measurement of PAHs from fireworks burning is urgently needed for source apportionment studies in the future. Copyright © 2015 Elsevier B.V. All rights reserved.

Particulate matter speciation profiles for light-duty gasoline vehicles in the United States.

PubMed

Sonntag, Darrell B; Baldauf, Richard W; Yanca, Catherine A; Fulper, Carl R

2014-05-01

Representative profiles for particulate matter particles less than or equal to 2.5 microm (PM2.5) are developed from the Kansas City Light-Duty Vehicle Emissions Study for use in the US. Environmental Protection Agency (EPA) vehicle emission model, the Motor Vehicle Emission Simulator (MOVES), and for inclusion in the EPA SPECIATE database for speciation profiles. The profiles are compatible with the inputs of current photochemical air quality models, including the Community Multiscale Air Quality Aerosol Module Version 6 (AE6). The composition of light-duty gasoline PM2.5 emissions differs significantly between cold start and hot stabilized running emissions, and between older and newer vehicles, reflecting both impacts of aging/deterioration and changes in vehicle technology. Fleet-average PM2.5 profiles are estimated for cold start and hot stabilized running emission processes. Fleet-average profiles are calculated to include emissions from deteriorated high-emitting vehicles that are expected to continue to contribute disproportionately to the fleet-wide PM2.5 emissions into the future. The profiles are calculated using a weighted average of the PM2.5 composition according to the contribution of PM2.5 emissions from each class of vehicles in the on-road gasoline fleet in the Kansas City Metropolitan Statistical Area. The paper introduces methods to exclude insignificant measurements, correct for organic carbon positive artifact, and control for contamination from the testing infrastructure in developing speciation profiles. The uncertainty of the PM2.5 species fraction in each profile is quantified using sampling survey analysis methods. The primary use of the profiles is to develop PM2.5 emissions inventories for the United States, but the profiles may also be used in source apportionment, atmospheric modeling, and exposure assessment, and as a basis for light-duty gasoline emission profiles for countries with limited data. PM2.5 speciation profiles were developed from a large sample of light-duty gasoline vehicles tested in the Kansas City area. Separate PM2.5 profiles represent cold start and hot stabilized running emission processes to distinguish important differences in chemical composition. Statistical analysis was used to construct profiles that represent PM2.5 emissions from the U.S. vehicle fleet based on vehicles tested from the 2005 calendar year Kansas City metropolitan area. The profiles have been incorporated into the EPA MOVES emissions model, as well as the EPA SPECIATE database, to improve emission inventories and provide the PM2.5 chemical characterization needed by CMAQv5.0 for atmospheric chemistry modeling.

MOLECULAR MARKER ANALYSIS OF DEARS SAMPLES

EPA Science Inventory

Source apportionment based on organic molecular markers provides a promising approach for meeting the Detroit Exposure and Aerosol Research Study (DEARS) objective of comparing source contributions between community air monitoring stations and various neighborhoods. Source appor...