B. Zielinska et E. Fujita, THE COMPOSITION AND CONCENTRATION OF HYDROCARBONS IN THE RANGE OF C2 TO C18 IN DOWNTOWN LOS-ANGELES, CA, Research of chemical intermediates, 20(3-5), 1994, pp. 321-334
Ambient air samples were collected in the downtown Los Angeles (Califo
rnia) area and analyzed for non-methane hydrocarbons in the range of C
2 to C18. Two daily samples were collected, using stainless steel cani
sters and Tenax-TA solid adsorbent cartridges, over four days in Augus
t 1991. The samples were analyzed using high resolution gas chromatogr
aphic separation and Fourier transform infrared/mass spectrometric det
ection (GC/IRD/MSD) or flame ionization detection (FID) of individual
hydrocarbons. The comparison of hydrocarbon concentrations found in th
e Tenax and canister samples and the assessment of the contribution of
semivolatile hydrocarbons (C10-C18 range) to the sum of non-methane h
ydrocarbons (C2-C10 or C2-C12), as measured by the canister method, is
presented. This contribution ranges from approximately 7% to 15% (for
C10-C18 range) and approximately 3% to 8% (for C12-C18 range). The se
mivolatile hydrocarbons also contribute approximately 16% to the total
ozone forming potential of non-methane hydrocarbons.