References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-13-803-2013

Characteristics and sources of carbonaceous aerosols from Shanghai, China

Cao

J.-J.

¹ ² Zhu

C.-S.

¹ Tie

X.-X.

¹ ³ Geng

F.-H.

⁴ Xu

H.-M.

¹ Ho

S. S. H.

¹ Wang

G.-H.

¹ Han

Y.-M.

¹ Ho

K.-F.

⁵

Key Lab of Aerosol Science & Technology, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China

Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an, China

National Center for Atmospheric Research, Boulder, CO, USA

Shanghai Meteorological Bureau, Shanghai, China

School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China

22 01 2013

13 2 803 817

This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article is available from http://www.atmos-chem-phys.net/13/803/2013/acp-13-803-2013.html

The full text article is available as a PDF file from http://www.atmos-chem-phys.net/13/803/2013/acp-13-803-2013.pdf

An intensive investigation of carbonaceous PM2.5 and TSP (total suspended particles) from Pudong (China) was conducted as part of the MIRAGE-Shanghai (Megacities Impact on Regional and Global Environment) experiment in 2009. Data for organic and elemental carbon (OC and EC), organic species, including C17 to C40 n-alkanes and 17 polycyclic aromatic hydrocarbons (PAHs), and stable carbon isotopes OC (δ13COC) and EC (δ13CEC) were used to evaluate the aerosols' temporal variations and identify presumptive sources. High OC/EC ratios indicated a large fraction of secondary organic aerosol (SOA); high char/soot ratios indicated stronger contributions to EC from motor vehicles and coal combustion than biomass burning. Diagnostic ratios of PAHs indicated that much of the SOA was produced via coal combustion. Isotope abundances (δ13COC = −24.5 ± 0.8&permil; and δ13CEC = −25.1 ± 0.6&permil;) indicated that fossil fuels were the most important source for carbonaceous PM2.5 (particulate matter less than 2.5 micrometers in diameter), with lesser impacts from biomass burning and natural sources. An EC tracer system and isotope mass balance calculations showed that the relative contributions to total carbon from coal combustion, motor vehicle exhaust, and SOA were 41%, 21%, and 31%; other primary sources such as marine, soil and biogenic emissions contributed 7%. Combined analyses of OC and EC, n-alkanes and PAHs, and stable carbon isotopes provide a new way to apportion the sources of carbonaceous particles.

References 1

Agnihotri, R. Mandal, T. K., Karapurkar, S., Naja, M., Gadi, R., Ahammed, Y. N., Kumar, A., Saud, T., and Saxena, M.: Stable carbon and nitrogen isotopic composition of bulk aerosols over India and northern Indian Ocean, Atmos. Environ., 45, 2828–2835, 2011.

Arimoto, R., Duce, R. A., Savoie, D. L., Prospero, J. M., Talbot, R., Cullen, J. D., Tomza, U., Lewis, N. F., and Ray, B. J.: Relationships among aerosol constituents from Asia and the North Pacific during PEM-West A, J. Geophys. Res., 101, 2011–2023, 1996.

Bi, X. H., Sheng, G. Y., Peng, P. A., Zhang Z. Q., and Fu, J. M.: Extractable organic matter in PM from LiWan district of Guangzhou City, PR China, Sci. Total Environ., 300, 213–228, 2002.

Bi, X. H., Simoneit, R. T. B., Sheng, G. Y., Ma, S. X., and Fu, J. M.: Composition and major sources of organic compounds in urban aerosols, Atmos. Res., 88, 256–265, 2008.

Borras, E. and Tortajada-Genaro, L. A.: Characterisation of polycyclic aromatic hydrocarbons in atmospheric aerosols by gas chromatography-mass spectrometry, Anal. Chim. Acta, 583, 266–276, 2007.

Cachier, H., Buat-Menard, P., and Fontugne, M.: Source terms and source strengths of the carbonaceous aerosol in the tropics, J. Atmos. Chem. 3, 469–489, 1985.

Cachier, H., Buat-Menard, P., Fontugne, M., and Chesselet, R.: Long-range transport of continentally-derived particulate carbon in the marine atmosphere: evidence from stable carbon isotopes studies, Tellus 38B, 161–177, 1986.

Cao, J. J., Lee, S. C., Ho, K. F., Zhang, X. Y., Zou, S. C., Fung, K. K., Chow, J. C., and Watson, J. G.: Characteristics of carbonaceous aerosol in Pearl River Delta Region, China during 2001 winter period, Atmos. Environ., 37, 1451–1460, 2003.

Cao, J. J., Lee, S. C., Ho, K. F., Zou, S. C., Fung, K., Li, Y., Watson, J. G., and Chow, J. C.: Spatial and seasonal variations of atmospheric organic carbon and elemental carbon in Pearl River Delta Region, China, Atmos. Environ., 38, 4447–4456, 2004.

Cao, J. J., Wu, F., Chow, J. C., Lee, S. C., Li, Y., Chen, S. W., An, Z. S., Fung, K. K., Watson, J. G., Zhu, C. S., and Liu, S. X.: Characterization and source apportionment of atmospheric organic and elemental carbon during fall and winter of 2003 in Xi'an, China, Atmos. Chem. Phys., 5, 3127–3137, http://dx.doi.org/10.5194/acp-5-3127-2005doi:10.5194/acp-5-3127-2005, 2005.

Cao, J. J., Lee, S. C., Chow, J. C., Watson, J. G., Ho, K. F., Zhang, R. J., Jin, Z. D., Shen, Z. X., Chen, G. C., Kang, Y. M., Zou, S. C., Zhang, L. Z., Qi, S. H., Dai, M. H., Cheng, Y., and Hu, K.: Spatial and seasonal distributions of carbonaceous aerosols over China, J. Geophys. Res., 112, D22S11, http://dx.doi.org/10.1029/2006JD008205doi:10.1029/2006JD008205, 2007.

Cao, J. J., Zhu, C. S., Chow, J. C., Liu, W. G., Han, Y. M., and Watson, J. G.: Stable carbon and oxygen isotopic composition of carbonate in fugitive dust in the Chinese Loess Plateau, Atmos. Environ., 42, 9118–9122, 2008.

Cao, J. J., Chow, J. C., Tao, J., Lee, S. C., Watson, J. G., Ho, K. F., Wang, G. H., Zhu, C. S., and Han, Y. M.: Stable carbon isotopes in aerosols from Chinese cities: Influence of fossil fuels, Atmos. Environ., 45, 1359–1363, 2011.

Cass, G. R.: Organic molecular tracers for particulate air pollution sources, Trends Anal. Chem., 17, 356–366, 1998.

Castro, L. M., Pio, C. A., Harrison, R. M., and Smith, D. J. T.: Carbonaceous aerosol in urban and rural European atmospheres: estimation of secondary organic carbon concentrations, Atmos. Environ., 33, 2771–2781, 1999.

Charlson, R. J., Scharwtz, S. E., Hales, J. M., Cess, R. D., Coakley Jr., J. A., Hansen, J. E., and Hofman, D. J.: Climate forcing by anthropogenic aerosols, Science, 255, 423–430, 1992.

Chen, Y. J., Feng, Y. L., Xiong, S. C., Liu, D. Y., Wang, G., Sheng, G. Y., and Fu, J. M.: Polycyclic aromatic hydrocarbons in the atmosphere of Shanghai, China, Environ. Monit. Assess., 172, 235–247, 2011.

Chow, J. C., Watson, J. G., Lu, Z., Lowenthal, D. H., Frazier, C. A.,Solomon, P. A., Thuillier, R. H., and Magliano, K. L.: Descriptiveanalysis of PM2.5 and PM10 at regionally representativelocations during SJVAQS/AUSPEX, Atmos. Environ., 30, 2079–2112, 1996.

Chow, J. C., Watson, J. G., Kuhns, H. D., Etyemezian, V., Lowenthal, D. H., Crow, D. J., Kohl, S. D., Engelbrecht, J. P., and Green, M. C.: Source profiles for industrial, mobile, and area sources in the Big Bend Regional Aerosol Visibility and Observational (BRAVO) Study, Chemosphere, 54, 185–208, 2003.

Chow, J. C., Watson, J. G., Pritchett, L. C., Pierson, W. R., Frazier, C. A., and Purcell, R. G.: The DRI thermal/optical reflectance carbon analysis system: Description, evaluation and applications in U.S. air quality studies, Atmos. Environ., 27, 1185–1201, 1993.

Chow, J. C., Watson, J. G., Chen, L. W. A., Arnott, W. P., Moosmuller, H., and Fung, K. K.: Equivalence of elemental carbon by thermal/optical reflectance and transmittance with different temperature protocols, Environ. Sci. Technol., 38, 4414–4422, 2004.

Chow, J. C., Yu, J. Z., Watson, J. G., Ho, S. S. H., Bohannan, T. L., Hays, M. D., and Fung, K. K.: The application of thermal methods for determining chemical composition of carbonaceous aerosols: a review, J. Environ. Sci. Health, Part A, 42, 1521–1541, 2007.

Currie, L. A., Klouda, G. A., Benner, B. A., Garrity, K., and Eglinton, T. I.: Isotopic and molecular fractionation in combustion; three routes to molecular marker validation, including direct molecular dating (GC/AMS), Atmos. Environ., 33, 2789–2806, 1999.

Currie, L. A., Klouda, G. A., Klinedinst, D. B., Sheffield, A. E., Jull, A. J. T., Donahue, D. J., and Connolly, M. V.: Fossil- and bio-mass combustion: C-14 for source identification, chemical tracer development, and model validation, Nucl. Instrum. Methods., B92, 404–409, 1994.

Dockery, D. W., Pope, C. A., Xu, X., Spengler, J. D., Ware, J. H., Fay, M. E., Ferris, B. G., and Speizer, F. E.: An association between air pollution and mortality in six U.S. cities, New Engl. J. Med., 329, 1753–1759, 1993.

Duan, F. K., He, K. B., Ma, Y. L., Yang, F. M., Yu, X. C., Cadle, S. H., Chan, T., and Mulawa, P. A.: Concentration and chemical characteristics of PM$_2.5$ in Beijing, China: 2001–2002, Sci. Total Environ., 355, 264–275, 2006.

Feng, J. L., Chan, C. K., Fang, M., Hu, M., He, L. Y., and Tang. X. Y.: Characteristics of organic matter in PM$_2.5$ in Shanghai, Chemosphere, 64, 1393–1400, 2006a.

Feng, J. L., Hu, M., Chan, C. K., Lau, P. S., Fang, M., He, L. Y., and Tang, X. Y.: A comparative study of the organic matter in PM$_2.5$ from three Chinese megacities in three different climatic zones, Atmos. Environ., 40, 3983–3994, 2006b.

Feng, Y. L., Chen, Y. J., Guo, H., Zhi G. R., Xiong, S. C., Li, J., Sheng, G. Y., and Fu, J. M.: Characteristics of organic and elemental carbon in PM$_2.5$ samples in Shanghai, China, Atmos. Res., 92, 434–442, 2009.

Fraser, M. P., Cass, G. R., and Simoneit, B. R. T.: Gas-phase and particle-phase organic compounds emitted from motor vehicle traffic in a Los Angeles roadway tunnel, Environ. Sci. Technol., 32, 2051–2060, 1998.

Friedli, H. R., Arellano Jr., A. F., Geng, F., Cai, C., and Pan, L.: Measurements of atmospheric mercury in Shanghai during September 2009, Atmos. Chem. Phys., 11, 3781–3788, http://dx.doi.org/10.5194/acp-11-3781-2011doi:10.5194/acp-11-3781-2011, 2011.

Gleason, J. D. and Kyser, T. K.: Stable isotope compositions of gases and vegetation near naturally burning coal, Nature, 307, 254–257, 1984.

Gray, H. A., Cass, G. R., Huntzicker, J. J., Heyerdahl, E. K., and Rau, J. A.: Characterization of atmospheric organic and elemental carbon particle concentrations in Los Angeles, Sci. Total Environ., 20, 580–589, 1986.

Greenberg, A.: Phenomenological study of benzo[a]pyrene and cyclopenteno[cd]pyrene decay in ambient air using winter/summer comparisons, Atmos. Environ., 23, 2797–2799, 1989.

Grimmer, G., Jacob, J., and Naujack, K. W.: Profile of the polycyclic aromatic compounds from crude oils. 3. Inventory by GC, GC/MSPAH in environmental materials, Fresen. Z. Anal. Chem. 316, 29–36, 1983.

Gu, Z. P., Feng, J. L., Han, W. L., Li, L., Wu, M. H., Fu, J. M., and Sheng, G. Y.: Diurnal variations of polycyclic aromatic hydrocarbons associated with PM2.5 in Shanghai, China, J. Environ. Sci., 22, 389–396, 2010.

Guo, Z. G., Lin, T., Zhang, G., Hu, L. M., and Zheng, M.: Occurrence and sources of polycyclic aromatic hydrocarbons and $n$-alkanes in PM$_2.5$ in the roadside environment of a major city in China, J. Hazard. Mater., 170, 888–894, 2009.

Guo, Z. G., Sheng, L. F., Feng, J. L., and Fang, M.: Seasonal variation of solvent extractable organic compounds in the aerosols in Qingdao, China, Atmos. Environ., 37, 1825–1834, 2003.

Han, Y. M., Cao, J. J., Chow, J. C., Watson, J. G., Fung, K. K., Jin, Z. D., Liu, S. X., and An, Z. S.: Evaluation of the thermal/optical reflectance method for discrimination between soot- and char-EC, Chemosphere 69, 569–574, 2007.

Han, Y. M., Lee, S. C., Cao, J. J., Ho, K. F., and An, Z. S.: Spatial distribution and seasonal variation of char-EC and soot-EC in the atmosphere over China, Atmos. Environ., 43, 6066–6073, 2009.

Han, Y. M., Cao, J. J., Lee, S. C., Ho, K. F., and An, Z. S.: Different characteristics of char and soot in the atmosphere and their ratio as an indicator for source identification in Xi'an, China, Atmos. Chem. Phys., 10, 595–607, http://dx.doi.org/10.5194/acp-10-595-2010doi:10.5194/acp-10-595-2010, 2010.

He, L. Y., Hu, M., Huang, X. F., Zhang, Y. H., and Tang, X. Y.: Seasonal pollution characteristics of organic compounds in atmospheric fine particles in Beijing, Sci. Total Environ., 359, 167–176, 2006.

He, K., Yang, F., Ma, Y., Zhang, Q., Yao, X., Chan, C. K., Cadle, S., Chan, T., and Mulawa, P.: The characteristics of PM$_2.5$ in Beijing, China, Atmos. Environ., 35, 4959–4970, 2001.

Ho, K. F., Lee, S. C., Cao, J. J., Li, Y. S., Chow, J. C., Watson, J. G., and Fung, K.: Variability of organic and elemental carbon, water soluble organic carbon, and isotopes in Hong Kong, Atmos. Chem. Phys., 6, 4569–4576, http://dx.doi.org/10.5194/acp-6-4569-2006doi:10.5194/acp-6-4569-2006, 2006.

Ho, S. S. H. and Yu, J. Z.: In-injection port thermal desorption and subsequent gas chromatography-mass spectrometric analysis of polycyclic aromatic hydrocarbons and $n$-alkanes in atmospheric aerosol samples, J. Chromatogr. A., 1059, 121–129, 2004.

Ho, S. S. H, Yu, J. Z., Chow, J. C., Zielinska, B., Watson, J. G., Sit, E. H. L., and Schauer, J. J.: Evaluation of an in-injection port thermal desorption-gas chromatography/mass spectrometry method for analysis of non-polar organic compounds in ambient aerosol samples, J. Chromatogr. A., 1200, 217–227, 2008.

Ho, S. S. H, Chow, J. C., Watson, J. G., Ng, L. P. T., Kwok, Y., Ho, K. F., and Cao, J. J.: Precautions for in-injection port thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) as applied to aerosol filter samples, Atmos. Environ., 45, 1491-1496, 2011.

Hou, X. M., Zhuang, G. S., Sun, Y. L., and An, Z. S.: Characteristics and sources of polycyclic aromatic hydrocarbons and fatty acids in PM$_2.5$ aerosols in dust season in China, Atmos. Environ., 40, 3251–3262, 2006.

Huang, H., Zou, C. W., Cao, J. J., and Tsang, P. K.: Carbonaceous Aerosol Characteristics in Outdoor and Indoor Environments of Nanchang, China, during Summer 2009,J. Air Waste Manage. Assoc., 61, 1262–1272, 2011.

Intergovernmental Panel on Climate Change (IPCC) Climate Change 2007: The Physical Science Basic, in: Changes in atmospheric constituents and in radiative forcing, edited by: Forster, P., Ramaswamy, V., Artaxo, P., Berntsen, T., Betts, R., Fahey, D. W., Haywood, J., Lean, J., Lowe, D. C., Myhre, G., Nganga, J., Prinn, R., Raga, G., Schulz, M., and Dorland, R. V., Cambridge University Press, UK, 129–234, 2007.

Jacobson, M. C., Hansson, H. C., Noone, K. J., and Charlson, R. J.: Organic atmospheric aerosols: review and state of the science, Rev. Geophys., 38, 267–294, 2000.

Khalili, N. R., Scheff, P. A., and Holsen, T. M.: PAH source fingerprints for coke ovens, diesel and gasoline engines, highway tunnels, and wood combustion emissions, Atmos. Environ., 29, 533–542, 1995.

Kim, K. H., Sekiguchi, K., Furuuchi, M., and Sakamoto, K.: Seasonal variation of carbonaceous and ionic components in ultrafine and fine particles in an urban area of Japan. Atmos. Environ., 45, 1581–1590, 2011a.

Kim, K. H., Sekiguchi, K., Kudo, S., and Sakamoto, K.: Characteristics of Atmospheric Elemental Carbon (Char and Soot) in Ultrafine and Fine Particles in a Roadside Environment, Japan. Aerosol Air Qual. Res., 11, 1–12, 2011b.

Kuhlbusch, T. A. J.: Black carbon in soils, sediments, and ice cores, in: Environmental analysis and remediation, edited by: Meyers, R. A., John Wiley & Sons, Toronto, Canada, 813–823, 1997.

Lee, S. C., Ho, K. F., Chan, L. Y., Zielinska, B., and Chow, J. C.: Polycyclic aromatic hydrocarbons (PAHs) and carbonyl compounds in urban atmosphere of Hong Kong, Atmos. Environ., 35, 5949–5960, 2001.

Li, W. F., Peng, Y., and Bai, Z. P.: Distributions and sources of $n$-alkanes in PM$_2.5$ at urban, industrial and coastal sites in Tianjin, China, J. Environ. Sci., 22, 1551–1557, 2010.

Lim, H. J. and B. J. Turpin, Origins of primary and secondary organic aerosol in Atlanta: Results of time-resolved measurements during the Atlanta supersite experiment, Environ. Sci. Technol., 36, 4489–4496, 2002.

Masiello, C. A.: New directions in black carbon organic geochemistry, Mar. Chem., 92, 201–213, 2004.

Mauderly, J. L. and Chow, J. C.: Health effects of organic aerosols, Inhal. Toxicol., 20, 257–288, 2008.

Mori, I., Nishikawa, M., Quan, H., and Iwasaka, Y.: Regional characteristics of Chinese atmospheric aerosols in terms of the stable carbon isotope ratios. In: Abstract of annual meeting of Japan Society for Atmospheric Environment (in Japanese), 40, p. 419, 1999.

Nielsen, T.: The decay of benzo[a]pyrene and cyclopenteno[cd]pyrene in the atmosphere, Atmos. Environ., 22, 2249–2254, 1988.

Okuda, T., Okamoto, K., Tanaka, S., Shen, Z. X., Han, Y. M., and Huo, Z. Q.: Measurement and source identification of polycyclic aromatic hydrocarbons (PAHs) in the aerosol in Xi'an, China, by using automated column chromatography and applying positive matrix factorization (PMF), Sci. Total Environ., 408, 1909–1914, 2010.

Omar, N. Y. M. J., Abas, M. R. B., Ketuly, K. A., and Tahir, N. M.: Concentrations of PAHs in atmospheric particles (PM$_10$) and roadside soil particles collected in Kuala Lumpur, Malaysia, Atmos. Environ., 36, 247–254, 2002.

Peltzer, E. T. and Gagosian, R. B.: Organic geochemistry of aerosols over the Pacific Ocean, in: Chemical Oceanography, edited by: Riley, J. P. and Chester, R., Academic Press, London, 10, 281–338, 1989.

Ramana, M. V., Ramanathan, V., Feng, Y., Yoon, S.-C., Kim, S.-W., Carmichael, G. R., and Schauer, J. J.: Warming influenced by the ratio of black carbon to sulphate and the black-carbon source, Nat. Geosci., 3, 542–545, 2010.

Reid, J. S., Eck, T. F., Christopher, S. A., Koppmann, R., Dubovik, O., Eleuterio, D. P., Holben, B. N., Reid, E. A., and Zhang, J.: A review of biomass burning emissions part III: intensive optical properties of biomass burning particles, Atmos. Chem. Phys., 5, 827–849, http://dx.doi.org/10.5194/acp-5-827-2005doi:10.5194/acp-5-827-2005, 2005.

Santos, F. J. and Galceran, M. T.: Review: Modern developments in gas chromatography-mass spectrometry based environmental analysis, J. Chromatogr. A., 1000, 125–151, 2003.

Seinfeld, J. H. and Pankow, J. F.: Organic atmospheric particulate material, Annu. Rev. Phys. Chem., 54, 121–140, 2003.

Shen, Z. X., Cao, J. J., Arimoto, R., Zhang, R. J., Jie, D. M., Liu, S. X., and Zhu, C. S.: Chemical composition and source characterization of spring aerosol over Horqinsandland in northeastern China, J. Geophys. Res., 112, D14315, http://dx.doi.org/10.1029/2006JD007991doi:10.1029/2006JD007991, 2007.

Shen, Z. X., Cao, J. J., Tong, Z., Liu, S. X., Lingala Siva Sankara Reddy, Han, Y. M., Zhang, T., and Zhou, J.: Chemical characteristics of submicron particles in winter in Xi'an, Aerosol Air Qual. Res., 9, 80–93, 2009.

Sicre, M. A., Marty, J. C., Saliot, A., Aparicio, X., Grimalt, J., and Albaiges, J.: Aliphatic and aromatic hydrocarbons in different sized aerosols over the Mediterranean Sea Occurrence and origin, Atmos. Environ., 21, 2247–2259, 1987.

Simoneit, B. R. T.: Organic matter of the troposphere: Characterization and sources of petroleum and pyrogenic residues in aerosols over the Western United States, Atmos. Environ., 18, 51–67, 1984.

Simoneit, B. R. T.: Application of molecular marker analysis to vehicular exhaust for source reconciliations, Int. J. Anal. Chem., 22, 203–233, 1985.

Turekian, V. C., Macko, S., Ballentine, D., Swap, R. J., and Garstang, M.: Causes of bulk carbon and nitrogen isotopic fractionations in the products of vegetation burns: laboratory studies, Chem. Geol., 152, 181–192, 1998.

Turpin, B. J. and Huntzicker, J. J.: Identification of secondary aerosol episodes and quantification of primary and secondary organic aerosol concentrations during SCAQS. Atmos. Environ., 29, 3527–3544, 1995.

Turpin, B. J. and Lim, H. J.: Species contributions to PM$_2.5$ mass concentrations: revisiting common assumptions for estimating organic mass, Aerosol Sci. Technol., 35, 602–610, 2001.

Turpin, B. J., Saxena, P., and Andrews, E.: Measuring and simulating particulate organics in the atmosphere: Problems and prospects, Atmos. Environ., 34, 2983–3013, 2000.

USEPA, Compendium of methods for the determination of toxic organic compounds in ambient air, Method TO-13A: Determination of polycyclic aromatic hydrocarbons (PAHs) in ambient air using gas chromatography/mass spectrometry (GC-MS), Washington, DC, 1997.

vanDrooge, B. L. Nikolova, I., and Pérez Ballesta, P.: Thermal desorption gas chromatography mass spectrometry as an enhanced method for the quantification of polycyclic aromatic hydrocarbons from ambient air particulate matter, J. Chromatogr. A., 1216, 4030–4039, 2009.

Wang, Y., Zhuang, G., Sun, Y, and An, Z.: The variation of characteristics and formation mechanisms of aerosols in dust, haze, and clear days in Beijing, Atmos. Environ., 40, 6579–6591, 2006.

Wang, G. H., Kawamura, K., Lee, S. C., Ho, K. F., and Cao, J. J.: Molecular, seasonal, and spatial distributions of organic aerosols from fourteen Chinese cities, Environ. Sci. Technol., 40, 4619–4625, 2006.

Watson, J. G., Chow, J. C., and Houck, J. E.: PM$_2.5$ chemical source profiles for vehicle exhaust, vegetative burning, geological material, and coal burning in northwestern Colorado during 1995, Chemosphere, 43, 1141–1151, 2001.

Widory, D.: Combustibles, fuels and their combustion products: a view through carbon isotopes. Combust.Theor.Model 10, 831-841, 2006.

Widory, D., Roy, S., Le Moullec, Y., Goupil, G., Cocherie, A., and Guerrot, C.: The origin of atmospheric particles in Paris: a view through carbon and lead isotopes, Atmos. Environ., 38, 953–961, 2004.

Yang, F., He, K., Ye, B., Chen, X., Cha, L., Cadle, S. H., Chan, T., and Mulawa, P. A.: One-year record of organic and elemental carbon in fine particles in downtown Beijing and Shanghai, Atmos. Chem. Phys., 5, 1449–1457, http://dx.doi.org/10.5194/acp-5-1449-2005doi:10.5194/acp-5-1449-2005, 2005.

Yao, X., Chan, C. K., Fang, M., Cadle, S., Chan, T., Mulawa, P., He, K., and Ye, B.: The water-soluble ionic composition of PM$_2.5$ in Shanghai and Beijing, China, Atmos. Environ., 36, 4223-4234, 2002.

Ye, B. M., Ji, X. L., Yang, H. Z., Yao, X. H., Chan, C. K., Cadle, S. H., Chan, T., and Mulaw, P. A.: Concentration and chemical composition of PM$_2.5$ in Shanghai for a 1-year period, Atmos. Environ., 37, 499–510, 2003.

Zeng, T. and Wang, Y. H.: Nationwide summer peaks of OC/EC ratios in the contiguous United States, Atmos. Environ., 45, 578–586, 2011.

Zhang, M. G., Han, Z. W., and Zhu, L. Y.: Simulation of atmospheric aerosols in East Asia using modeling system RAMS-CMAQ: model evaluation, China Particuol., 5, 321–327, 2007.

Zhang, R. J., Ho, K. F., Cao, J. J., Han, Z. W., Zhang, M. G., Cheng, Y., and Lee, S. C.: Organic carbon and elemental carbon associated with PM$_10$ in Beijing during spring time, J. Hazard Mater., 172, 970–977, 2009.

Zhao, J. P., Zhang, F. W., Chen, J. S., and Xu, Y.: Characterization of polycyclic aromatic hydrocarbons and gas/particle partitioning in a coastal city, Xiamen, Southeast China, J. Environ. Sci., 22, 1014–1022, 2010.

Zheng, M. and Fang M.: Particle-associated polycyclic aromatic hydrocarbons in the atmosphere of Hong Kong, Water Air Soil Pollut., 117, 175–189, 2000.

Zheng, M., Fang, M., Wang, F., and To, K. L.: Characterization of the solvent extractable organic compounds in PM$_2.5$ aerosols in Hong Kong, Atmos. Environ., 342, 691–702, 2000.

Zhu, C. S., Chen, S. C., Cao, J. J., Tsai, C. J., Chou, C. C. K., Liu, S. C., and Roam, G. D.: Characterization of carbon fractions for atmospheric fine particles and nanoparticles in a highway tunnel, Atmos. Environ., 44, 2668–2673, 2010.