ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-10193-2011 Technical Note: On the effect of water-soluble compounds removal on EC quantification by TOT analysis in urban aerosol samples Piazzalunga A. 1 3 Bernardoni V. 2 Fermo P. 1 Valli G. 2 Vecchi R. 2 Department of Inorganic, Metallorganic and Analytical Chemistry, Università degli Studi di Milano, Via Venezian 22, 20133 Milan, Italy Department of Physics, Università degli Studi di Milano, Via Celoria 16, 20133 Milan, Italy now at: Department of Environmental and Territorial Sciences, Università di Milano-Bicocca, Piazza della Scienza 1, 20126 Milan, Italy 11 10 2011 11 19 10193 10203 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/11/10193/2011/acp-11-10193-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/10193/2011/acp-11-10193-2011.pdf

In this work, three different thermal protocols were tested on untreated and water-washed aerosol samples to study the influence of soluble organic and inorganic compounds on EC measurements. Moreover, analyses on the water soluble extracts were carried out. The aim was to find out the most suitable protocol to analyse samples collected in a heavily polluted area. Indeed, the tests were performed on real samples collected at an urban background station in the Po Valley, which is one of the main pollution hot-spots in Europe. <br><br> The main differences among the tested protocols were the maximum temperature of the He step (i.e. 870 °C, 650 °C, and 580 °C) and the duration of the plateaus during the heating procedure. Our measurements evidenced the presence of a significant amount of weakly light-absorbing carbonaceous aerosol evolving during the highest temperature step in He (i.e. 870 °C), which makes lower temperature protocols not suitable for EC determination in samples collected in heavily polluted areas like Milan.

 References Andreae, M. O. and Crutzen, P. J.: Atmospheric Aerosols: Biogeochemical Sources and Role in Atmospheric Chemistry, Science, 276, 1052–1058, 1997. Andreae, M. O. and Gelencsér, A.: Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols, Atmos. Chem. Phys., 6, 3131–3148, http://dx.doi.org/10.5194/acp-6-3131-2006doi:10.5194/acp-6-3131-2006, 2006. Bernardoni, V., Vecchi, R., Valli, G., Piazzalunga, A., and Fermo, P.: PM$_10$ source apportionment in Milan (Italy) using time-resolved data, Sci. Total Environ., 409, 4788-4795, 2011.. Birch, M. E. and Cary, R. A.: Elemental Carbon–Based Method for Monitoring Occupational Exposures to Particulate Diesel Exhaust, Aerosol Sci. Tech., 25, 221–241, 1996. Boparai, P., Lee, J., and Bond, T. C.: Revisiting Thermal-Optical Analyses of Carbonaceous Aerosol Using a Physical Model, Aerosol Sci. Tech., 42, 930–948, 2008. Cavalli, F., Viana, M., Yttri, K. E., Genberg, J., and Putaud, J.-P.: Toward a standardised thermal-optical protocol for measuring atmospheric organic and elemental carbon: the EUSAAR protocol, Atmos. Meas. Tech., 3, 79–89, http://dx.doi.org/10.5194/amt-3-79-2010doi:10.5194/amt-3-79-2010, 2010. 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 US Air Quality Studies, Atmos. Environ. A-Gen., 27, 1185–1201, 1993. Chow, J. C., Watson, J. G., Crow, D., Lowental, D. H., and Merrifield, T.: Comparison of IMPROVE and NIOSH Carbon Measurements, Aerosol Sci. Technol., 34, 23–34, 2001. Chow, J. C., Watson, J. G., Chen, L.-W. A., Arnott, W. P., and Moosmüller, H.: Equivalence of Elemental Carbon by Thermal/Optical Reflectance and Transmittance with Different Temperature Protocols, Environ. Sci. Technol., 38, 4414–4122, 2004. Chow, J. C., Watson, J. G., Chen, L. W., Chang, M. C., Robinson, N. F., Trimble, D., and Kohl, S.: The IMPROVE_A temperature protocol for thermal/optical carbon analysis: maintaining consistency with a long-term database, J. Air Waste Manage, 57, 1014–1023, 2007. Conny, J. M., Klinedinst, D. B., Wight, S. A., and Paulsen, J. L.: Optimizing Thermal-Optical Methods for Measuring Atmospheric Elemental (Black) Carbon: A Response Surface Study, Aerosol Sci. Technol., 37, 703–723, 2003. Cuccia, E., Piazzalunga, A., Bernardoni, V., Brambilla, L., Fermo, P., Massabò, D., Molteni, U., Prati, P., Valli, G., Vecchi, R.: Carbonate measurements in PM$_10$ near the marble quarries of Carrara (Italy) by infrared spectroscopy (FT-IR) and source apportionment by positive matrix factorization (PMF), Atmos. Environ., 45, 6481–6487, 2011. Fermo, P., Piazzalunga, A., Tuccillo, F., Brambilla, L., Cazzuli, O., Vecchi, R., and Valli, G.: Analytical methods for quantification and characterization of HULIS (HUmic Like Substances) in atmospheric aerosol, European Aerosol Conference, Karlsruhe, Germany, 6–11 September 2009, T022A18, 2009. Gilardoni, S., Vignati, E., Marmer, E., Cavalli, F., Belis, C., Gianelle, V., Loureiro, A., and Artaxo, P.: Sources of carbonaceous aerosol in the Amazon basin, Atmos. Chem. Phys., 11, 2747–2764, http://dx.doi.org/10.5194/acp-11-2747-2011doi:10.5194/acp-11-2747-2011, 2011. Hitzenberger, R. and Rosati, B.: Laboratory investigation of interferences in thermal and optical carbon analysis, International Aerosol Conference, Helsinki, Finland, 29 August–3 September 2010, 3A3, 2010. Iinuma, Y., Brüggemann, E., Gnauk, T., Andreae, M. O., Helas, G., Müller, K., Parmar, R., and Herrmann, H.: Source characterization of biomass burning particles: The combustion of selected European conifers, African hardwood, savannah grass, German peat and Indonesian peat, J. Geophys. Res., 112, D08209, http://dx.doi.org/10.1029/2006JD007120doi:10.1029/2006JD007120, 2007. Kuhlbusch, T. A. J., Borowiak, A., Gelenscer, A., Genberg, J., Gladtke, D., Maenhaut, W., Pio, C., Popoviecheva, O., Putaud, J.-P., Quincy, P., Sciare, J., ten Brink, H., Viana, M., and Yttri, K.E.: Measurement of Elemental and Organic carbon in Europe, JRC Scientific and Technical Reports (EUR collection), EUR23992 EN, available at http://publications.jrc.ec.europa.eu/repository/handle/111111111/7803/, 2009. Maenhaut, W. and Clayes, M.: Characterisation and sources of carbonaceous atmospheric aerosol, in: Scientific support plan for a sustainable development policy (SPSD~II), Belgian Science Policy, Bruxelles, Belgium, 2007. Novakov, T. and Corrigan, C. E.: Thermal Characterization of Biomass Smoke Particles, Mikrochim. Acta, 119, 157–166, 1995. Perrone, M. R., Piazzalunga, A., Prato, M., and Carofalo, I.: Composition of Fine and Coarse Particles in a coastal site of the Central Mediterranean: carbonaceous specie contributions, Atmos. Environ., http://dx.doi.org/10.1016/j.atmosenv.2011.04.030doi:10.1016/j.atmosenv.2011.04.030, in press, 2011. Piazzalunga, A., Abate, C., Bernardoni, V., Bianchi, F., Fermo, P., Paganelli, C., Valli, G., and Vecchi, R.: BC/EC assessment on real samples by optical/thermal methods with and without WSOC removal and using different protocols, International Aerosol Conference, Helsinki, Finland, 29 August–3 September 2010, 11D4, 2010a. Piazzalunga, A., Fermo, P., Bernardoni, V., Vecchi, R., Valli, G., and De Gregorio, M. A.: A simplified method for levoglucosan quantification in wintertime atmospheric particulate matter by high performance anion-exchange chromatography coupled with pulsed amperometric detection, Int. J. Environ. An. Ch., 90, 934–947, 2010b. Piazzalunga, A., Belis, C., Bernardoni, V., Cazzuli, O., Fermo, P., Valli, G., Vecchi, R.: Estimates of wood burning contribution to PM by the macro-tracer method using tailored emission factors, Atmos. Environ., http://dx.doi.org/10.1016/j.atmosenv.2011.09.008doi:10.1016/j.atmosenv.2011.09.008, in press, 2011. Querol, X., Pey, J., Pandolfi, M., Alastuey, A., Cusack, M., Pérez, N., Moreno, T., Viana, M., Mihalopoulos, N., Kallos, G., and Kleanthous, S.: African dust contributions to mean ambient PM$_10$ mass-levels across the Mediterranean Basin, Atmos. Environ., 43, 4266–4277, 2009. Schauer, J. J., Mader, B. T., Deminter, J. T., Heidmann, G., Bae, M. S., Seinfeld, J. H., Flagan, R. C., Cary, R. A., Smith, D., Huebert, B. J., Bertram, T., Howell, S., Kline, J. T., Quinn, P., Bates, T., Turpin, B., Lim, H. J., Yu, J. Z., Yang, H., and Keywood, M. D.: ACE-Asia Intercomparison of a Thermal-Optical Method for the Determination of Particle-Phase Organic and Elemental Carbon, Environ. Sci. Technol., 37, 993–1001, 2003. Schmid, H., Laskus, L., Abraham, H. J., Baltensperger, U., Lavanchy, V., Bizjak, M., Burba, P., Cachier, H., Crow, D., Chow, J., Gnauk, T., Even, A., ten Brink, H. M., Giesen, K.-P., Hitzenberger, R., Hueglin, C., Maenhaut, W., Pio, C., Carvalho, A., Putaud, J.-P., Toom-Sauntry, D., and Puxbaum H.: Results of the "carbon conference" international aerosol carbon round robin test stage I, Atmos. Environ., 35, 2111–2121, 2001. Schmidl, C., Bauer, H., Dattler, A., Hitzenberger, R., Weissenboeck, G., Marr, I. L., and Puxbaum, H.: Chemical characterisation of particle emissions from burning leaves, Atmos. Environ., 42, 9070–9079, 2008. Simoneit, B. R. T. and Elias, V. O.: Detecting organic tracers from biomass burning in the atmosphere, Mar. Pollut. Bull., 42, 805–810, 2001. Sillanpää, M., Frey, A., Hillamo, R., Pennanen, A. S., and Salonen, R. O.: Organic, elemental and inorganic carbon in particulate matter of six urban environments in Europe, Atmos. Chem. Phys., 5, 2869–2879, http://dx.doi.org/10.5194/acp-5-2869-2005doi:10.5194/acp-5-2869-2005, 2005. Subramanian, R., Khlystov, A. Y., and Robinson, A. L.: Effect of Peak Inert-Mode Temperature on Elemental Carbon Measured Using Thermal-Optical Analysis, Aerosol Sci. Technol., 40, 763–780, 2006. ten Brink, H., Maenhaut, W., Hitzenberger, R., Gnauk, T., Spindler, G., Even, A., Chi, H., Bauer, H., Puxbaum, H., Putaud, J.-P., Tursic, T., and Berner, A.: INTERCOMP2000: the comparability of methods in use in Europe for measuring the carbon content of aerosol, Atmos. Environ., 38, 6507–6519, 2004. Varga, B., Kiss, G., Ganszky, I., Gelencsér, A., and Krivàcsy, Z.: Isolation of water-soluble organic matter in atmospheric aerosol, Talanta, 55, 561–572, 2001. Vecchi, R., Valli, G., Fermo, P., D'Alessandro, A., Piazzalunga, A., and Bernardoni, V.: Organic and inorganic sampling artefacts assessment, Atmos. Environ., 43, 1713–1720, 2009. Wallén, A., Lidén, G., and Hansson, H.-C.: Measured Elemental Carbon by Thermo-Optical Transmittance Analysis in Water-Soluble Extracts from Diesel Exhaust, Woodsmoke, and Ambient Particulate Samples, J. Occup. Environ. Hyg., 7, 35–45, 2010. Wang, Y., Chung, A., and Paulson, S. E.: The effect of metal salts on quantification of elemental and organic carbon in diesel exhaust particles using thermal-optical evolved gas analysis, Atmos. Chem. Phys., 10, 11447–11457, http://dx.doi.org/10.5194/acp-10-11447-2010doi:10.5194/acp-10-11447-2010, 2010. Watson, J. G., Chow, J. C., and Chen, L.-W. A.: Summary of Organic and Elemental carbon/Black Carbon Analysis Methods and Intercomparisons, Aerosol Air Qual. Res., 5, 65–102, 2005. Yang, H. and Yu, J. Z.: Uncertainties in Charring Correction in the Analysis of Elemental and Organic Carbon in Atmospheric Particles by Thermal/Optical Methods, Environ. Sci. Technol., 36, 5199–5204, 2002. Yttri, K. E., Dye, C., Braathen, O.-A., Simpson, D., and Steinnes, E.: Carbonaceous aerosols in Norwegian urban areas, Atmos. Chem. Phys., 9, 2007–2020, http://dx.doi.org/10.5194/acp-9-2007-2009doi:10.5194/acp-9-2007-2009, 2009. Yu, J. Z., Xu, J. H., and Yang, H.: Charring Characteristics of Atmospheric Organic Particulate Matter in Thermal Analysis, Environ. Sci. Technol., 36, 754–761, 2002. Zhi, G., Chen, Y., Sheng, G., and Fu, J.: Effects of temperature parameters on thermal-optical analysis of organic and elemental carbon in aerosol, Environ. Monit. Assess., 154, 253–261, 2009.