Sources of fine organic aerosol. 4. Particulate abrasion products from leaf surfaces of urban plants
Abstract
Green and dead leaves from 62 plant species characteristic of the Los Angeles area were harvested and composited according to the actual leaf mass distribution for that area. To simulate leaf surface abrasion by the wind, the leaf composites were agitated in clean Teflon bags while a purified airstream flowed through. Fine particles (d_p ≤ 2 µm) shed from the leaf surfaces were extracted and analyzed using gas chromatography/mass spectrometry. Organic constituents including n-alkanes, n-alkanoic and n-alkenoic acids, n-alkanols, n-alkanals, terpenoid compounds, and trace amounts of PAH were identified and quantified. n-Alkanes showed similar concentrations in both dead and green leaf surface matter; mono-, sesqui-, and triterpenoids were depleted in dead leaf material while n-alkanoic acids were enriched in dead leaf abrasion products. It is shown that the higher molecular weight n-alkanes (C_(27)-C_(33)), with their pronounced odd/even carbon number predominance, provide a suitable marker compound assemblage for tracing vegetative detritus in the urban atmosphere.
Additional Information
© 1993 American Chemical Society. Received for review October 29, 1992. Revised manuscript received May 28, 1993. Accepted June 1, 1993. We thank Ed Ruth for his assistance with the acquisition of the mass spectrometry data, and the staffs at the Los Angeles County Arboretum, Rancho Santa Ana, and Eaton Canyon Park for assistance in identification of plant species. We thank also Lynn Salmon who helped in preparing the sampling protocol and in collecting the plant leaf samples. This research was supported by the California Air Resources Board under Agreement A932-127. Portions of the work benefited from research supported by the U.S. Environmental Protection Agency under Agreement R-813277-01-0 and by the South Coast Air Quality Management District. Partial funding also was provided by the US. Department of Energy under Contract DE-AC02-76CH00016. The statements and conclusions in the report are those of the contractor and not necessarily those of the California Air Resources Board. The mention of commercial products, their source, or their use in connection with material reported herein is not to be construed as actual or implied endorsement of such products. The manuscript has not been subject to the EPA's peer and policy review and hence does not necessarily reflect the views of the EPA.Additional details
- Eprint ID
- 63242
- Resolver ID
- CaltechAUTHORS:20151224-112718341
- A932-127
- California Air Resources Board (CARB)
- R-813277-01-0
- Environmental Protection Agency (EPA)
- South Coast Air Quality Management District (SCAQMD)
- DE-AC02-76CH00016
- Department of Energy (DOE)
- Created
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2016-01-04Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
- Caltech groups
- Environmental Quality Laboratory