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The chemical composition of atmospheric ultrafine particles

Cass, G. R. and Hughes, L. A. and Bhave, P. and Kleeman, M. J. and Allen, J. O. and Salmon, L. G. (2000) The chemical composition of atmospheric ultrafine particles. Philosophical Transactions A: Mathematical, Physical and Engineering Sciences, 358 (1775). pp. 2581-2592. ISSN 1364-503X.

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Atmospheric ultrafine particles (with diameter less than 0.1 μm) may be responsible for some of the adverse health effects observed due to air–pollutant exposure. To date, little is known about the chemical composition of ultrafine particles in the atmosphere of cities. Ultrafine particle samples collected by inertial separation on the lower stages of cascade impactors can be analysed to determine a material balance on the chemical composition of such samples. Measurements of ultrafine particle mass concentration made in seven Southern California cities show that ultrafine particle concentrations in the size range 0.056–0.1 μm aerodynamic diameter average 0.55–1.16 μg m^(−3). The chemical composition of these ultrafine particle samples averages 50% organic compounds, 14% trace metal oxides, 8.7% elemental carbon, 8.2% sulphate, 6.8% nitrate, 3.7% ammonium ion (excluding one outlier), 0.6% sodium and 0.5% chloride. The most abundant catalytic metals measured in the ultrafine particles are Fe, Ti, Cr, Zn, with Ce also present. A source emissions inventory constructed for the South Coast Air Basin that surrounds Los Angeles shows a primary ultrafine particle emissions rate of 13 tonnes per day. Those ultrafine particle primary emissions arise principally from mobile and stationary fuel combustion sources and are estimated to consist of 65% organic compounds, 7% elemental carbon, 7% sulphate, 4% trace elements, with very small quantities of sodium, chloride and nitrate. This information should assist the community of inhalation toxicologists in the design of realistic exposure studies involving ultrafine particles.

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Additional Information:© 2000 Royal Society. Published 15 October 2000. This research was supported by the US Environmental Protection Agency under agreement R-827354-01-0.
Funding AgencyGrant Number
Environmental Protection Agency (EPA)R-827354-01-0
Subject Keywords:ultrafine particles; atmospheric concentration; chemical composition; emissions rate
Issue or Number:1775
Record Number:CaltechAUTHORS:20160722-081625913
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Official Citation:The chemical composition of atmospheric ultrafine particles Glen R Cass, Lara A. Hughes, Prakash Bhave, Michael J. Kleeman, Jonathan O. Allen, Lynn G. Salmon Phil. Trans. R. Soc. Lond. A 2000 358 2581-2592; DOI: 10.1098/rsta.2000.0670. Published 15 October 2000
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:69155
Deposited By: Ruth Sustaita
Deposited On:26 Mar 2018 22:20
Last Modified:03 Oct 2019 10:19

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