Size‐resolved fine and ultrafine particle composition in Baltimore, Maryland

[1] The third-generation real-time single-particle mass spectrometer (RSMS-3) was deployed from March to December 2002 in Baltimore, Maryland, as part of the Baltimore Particulate Matter Supersite. The site was located to the east of the downtown area and northwest of many local industrial emission sites. RSMS-3 actively sampled and analyzed over 380,000 individual particles within the 48–770 nm size range. The resulting positive and negative ion spectra for each particle were classified using a neural network algorithm, adaptive resonance theory ART 2-a. A subset of these data, particles analyzed between 1 April and 30 November 2003, is presented here. Over 99% of these particles could be described by 10 major composition types. Ambient number concentrations were determined for each type and correlated with particle size, wind direction, and time of day/year. On the basis of this information, local and regional sources of different composition classes are postulated. Almost 40% of all particles in the Baltimore aerosol are internally mixed, consisting primarily of organic carbon, ammonium nitrate, and ammonium sulfate. Most of these particles are likely derived from regional sources. The remaining particles appear to be derived mainly from local sources and processes and include elemental carbon (almost 30%), ammonium nitrate (over 10%), and various metals (over 20%). The particle composition types found in Baltimore aerosol are compared to previous measurements in Houston and Atlanta.

[1]  Bernhard Spengler,et al.  Chemical classes of atmospheric aerosol particles at a rural site in Central Europe during winter , 2002 .

[2]  Halûk Özkaynak,et al.  Continuous measurement of fine and ultrafine particulate matter, criteria pollutants and meteorological conditions in urban El Paso, texas , 2003 .

[3]  K. Prather,et al.  Real-time measurements of the chemical composition of size-resolved particles during a Santa Ana wind episode, California USA , 2001 .

[4]  H. Burtscher,et al.  Real-time characterization of ultrafine and accumulation mode particles in ambient combustion aerosols , 2002 .

[5]  K. Deboudt,et al.  European isotopic signatures for lead in atmospheric aerosols: a source apportionment based upon 206Pb/207Pb ratios. , 2002, The Science of the total environment.

[6]  High Speed Particle Beam Generation: A Dynamic Focusing Mechanism for Selecting Ultrafine Particles , 2000 .

[7]  Performance of a Single Ultrafine Particle Mass Spectrometer , 2002 .

[8]  Nanoparticle Detection by Aerosol Mass Spectrometry , 2001 .

[9]  J. Chow,et al.  The Treasure Valley secondary aerosol study I : measurements and equilibrium modeling of inorganic secondary aerosols and precursors for southwestern Idaho , 2003 .

[10]  Ulf Kirchner,et al.  Identification of diesel exhaust particles at an Autobahn, urban and rural location using single-particle mass spectrometry , 2003 .

[11]  A S Wexler,et al.  Application of the ART-2a algorithm to laser ablation aerosol mass spectrometry of particle standards. , 2001, Analytical chemistry.

[12]  A. Wexler,et al.  Size‐resolved ultrafine particle composition analysis 2. Houston , 2003 .

[13]  A. Espinosa,et al.  A chemical speciation of trace metals for fine urban particles , 2002 .

[14]  P. Paatero,et al.  Receptor modeling of ambient and personal exposure samples: 1998 Baltimore Particulate Matter Epidemiology-Exposure Study , 2003 .

[15]  D. Murphy,et al.  Observations of organic material in individual marine particles at Cape Grim during the First Aerosol Characterization Experiment (ACE 1) , 1998 .

[16]  Juan Jimenez,et al.  An approach to characterization of sources of urban airborne particles through heavy metal speciation , 2000 .

[17]  A. Wexler,et al.  Ultrafine nitrate particle events in Baltimore observed by real-time single particle mass spectrometry , 2004 .

[18]  L. Chen,et al.  Origins of fine aerosol mass in the Baltimore–Washington corridor: implications from observation, factor analysis, and ensemble air parcel back trajectories , 2002 .

[19]  Noble,et al.  Real-time single particle mass spectrometry: a historical review of a quarter century of the chemical analysis of aerosols , 2000, Mass spectrometry reviews.

[20]  F. Divita,et al.  Size Spectra and Atmospheric Growth of V-Containing Aerosol in Washington, DC , 1996 .

[21]  Mahoney,et al.  In situ measurements of organics, meteoritic material, mercury, and other elements in aerosols at 5 to 19 kilometers , 1998, Science.

[22]  A. Wexler,et al.  Mass spectrometry of individual particles between 50 and 750 nm in diameter at the Baltimore Supersite. , 2003, Environmental science & technology.

[23]  G. Cass,et al.  The Magnitude of Bias in the Measurement of PM25 Arising from Volatilization of Particulate Nitrate from Teflon Filters. , 1999, Journal of the Air & Waste Management Association.

[24]  Allen,et al.  Direct observation of heterogeneous chemistry in the atmosphere , 1998, Science.

[25]  Jeffrey R. Whiteaker,et al.  Hydroxymethanesulfonate as a tracer for fog processing of individual aerosol particles , 2003 .

[26]  Ilhan Olmez,et al.  Physical and Chemical Characterization of Atmospheric Ultrafine Particles in the Los Angeles Area , 1998 .

[27]  S. Kreidenweis,et al.  A Method for Single Particle Mass Spectrometry of Ice Nuclei , 2003 .

[28]  Mun Young Choi,et al.  MEASUREMENT OF FRACTAL PROPERTIES OF SOOT AGGLOMERATES IN LAMINAR COFLOW DIFFUSION FLAMES USING THERMOPHORETIC SAMPLING IN CONJUNCTION WITH TRANSMISSION ELECTRON MICROSCOPY AND IMAGE PROCESSING , 2001 .

[29]  Detection of negative ions from individual ultrafine particles. , 2002, Analytical chemistry.

[30]  J. Seinfeld,et al.  The distribution of ammonium salts among a size and composition dispersed aerosol , 1990 .

[31]  K. Prather,et al.  Aerosol time‐of‐flight mass spectrometry during the Atlanta Supersite Experiment: 1. Measurements , 2003 .

[32]  J. Chow,et al.  The Treasure Valley secondary aerosol study II: modeling of the formation of inorganic secondary aerosols and precursors for southwestern Idaho , 2003 .

[33]  Peter Brimblecombe,et al.  Thermodynamic Model of the System H+−NH4+−SO42-−NO3-−H2O at Tropospheric Temperatures , 1998 .

[34]  K. Prather,et al.  Real-time measurements of the chemical composition of size-resolved particles during a Santa Ana wind episode, , 2001 .

[35]  D. Murphy,et al.  Chemical components of single particles measured with Particle Analysis by Laser Mass Spectrometry (PALMS) during the Atlanta SuperSite Project: Focus on organic/sulfate, lead, soot, and mineral particles , 2002 .

[36]  Daniel M. Murphy,et al.  On-line single-particle analysis by laser desorption mass spectrometry , 1991 .

[37]  John H. Seinfeld,et al.  Nitrate formation in atmospheric aerosols , 1977 .

[38]  A. Wexler,et al.  Number concentrations of fine and ultrafine particles containing metals , 2004 .

[39]  A. Wexler,et al.  The character of single particle sulfate in Baltimore , 2004 .

[40]  M. Johnston.  Sampling and analysis of individual particles by aerosol mass spectrometry. , 2000, Journal of mass spectrometry : JMS.

[41]  P. Paatero,et al.  Corrigendum to “Receptor modeling of ambient and personal exposure samples: 1998 Baltimore particulate matter epidemiology-exposure study”: [Atmospheric Environment 37 (23) (2003) 3289–3302] , 2003 .

[42]  Da-Ren Chen,et al.  Measurement of Atlanta Aerosol Size Distributions: Observations of Ultrafine Particle Events , 2001 .

[43]  G R Cass,et al.  Quantification of ATOFMS data by multivariate methods. , 2001, Analytical chemistry.

[44]  A. Wexler,et al.  Size-resolved ultrafine particle composition analysis, 1. Atlanta , 2003 .

[45]  Ronald W. Williams,et al.  Personal exposures to PM2.5 mass and trace elements in Baltimore, MD, USA , 2001 .

[46]  D. Murphy,et al.  Nitrate and oxidized organic ions in single particle mass spectra during the 1999 Atlanta Supersite Project , 2003 .