Isotopic (14C) and Chemical Composition of Atmospheric Volatile Organic Compounds-Precursors to Ozone

Published

September 1, 2000

Author(s)

George A. Klouda, C. W. Lewis, R A. Rasmussen, D C. Stiles, W D. Ellenson, J L. Marolf, R. K. Stevens

Abstract

Atmospheric volatile organic compounds (VOCs) are an important factor in the production of ozone near ground level [3]. Many hydrocarbons origanate from auto exhaust. However, a number of VOCs e.g., isoprene, are known to be natural in origin. To develop reliable modelsfor understanding how ozone levels might be controlled, it has been recognized that a key variable is the fractional amount of fossil vs. non-fossil (biogenic, uncontrollable) VOCs [1]. These two source categories are uniquely discriminated from each other based on the ¹⁴C abundance of VOC fractions. Combining isotopic measurements with chemical information will yield greater confidence in source estimates. Over the last 8 years, NIST, OGI and the U.S. EPA have explored sampling methods and analytical procedures to collect enough carbon from atmospheric non-methane VOC fractions to measure the ¹⁴C composition [4,9]. In doing so, this work also provided an opportunity to enhance the sensitivity of GC-FID and GC-MS for chemical identification and quantification. This paper will briefly describe the methods studied and present preliminary ¹⁴C and chemical results from Azusa, CA, Houston, TX, and Nashville, TN, USA.

Proceedings Title

Proceedings of the Third International Conference on Isotopes: Isotope Production and Applications in the 21st Century

Conference Dates

September 6-10, 1999

Conference Location

Vancouver,

Pub Type

Conferences

Keywords

atmospheric, ozone precursors, radiocarbon, sources, volatile organic compounds

Citation

Klouda, G. , Lewis, C. , Rasmussen, R. , Stiles, D. , Ellenson, W. , Marolf, J. and Stevens, R. (2000), Isotopic (¹⁴C) and Chemical Composition of Atmospheric Volatile Organic Compounds-Precursors to Ozone, Proceedings of the Third International Conference on Isotopes: Isotope Production and Applications in the 21st Century , Vancouver, (Accessed December 10, 2024)