|
32.
Chemical Characterization of Atmospheric Aerosol in Support of
Atlanta Health Study: Particle and Multiphase Organics
Hazem
S. EL-Zanan and Barbara Zielinska, Ph.D.
Desert
Research Institute, Division of Atmospheric Sciences, 2215 Raggio
Pkwy, Reno, NV 89512
In order to evaluate the hazardous air pollutants
in Atlanta, GA, samples of PM2.5 were collected for 24 hours using
the DRI sequential fine particulate/semi-volatile organic sampler.
Ninety-five samples including 78 combined dichloromethane (DCM)
and acetone extracts plus 17 water extracts were selected from
the 2-year sampling period for detailed chemical analysis. Analyses
of polycyclic aromatic hydrocarbons (PAHs), hopanes and steranes
and polar organic compounds were performed for all combined DCM
and acetone fractions, while the water extracts were analyzed
for polar organics only.
Results showed that the concentration of the total
PAHs including gas-phase PAHs (with the exception of naphthalene)
ranged from 0.06 - 4.3 µg/m3 which constitutes approximately
1 – 46% of the organic carbon concentration, and the particle-phase
PAHs constituted 1.4 – 8 % of the total PAHs mass concentrations.
The average total concentration of hopanes and steranes for all
samples was 10.5 ng/m3, which constitutes < 0.1 % of the average
organic carbon concentration of all samples. Hopanes constituted
62.5% of the total hopanes and steranes mass concentration and
it was found that the sum of the concentrations of 17a(H),12ß(H)-30-norhopane,
17ß(H),21a(H)-30-norhopane and 17a(H),21ß(H)-hopane
was about 25.6% of the total hopanes and steranes concentration
of the total polar organics for all samples. The mean polar compounds
concentration for all samples was 4.2 µg/m3 (with the exception
of hexanoic acid), which constitutes about 52% of the average
organic carbon concentration. The mean levoglucosan concentration
for all samples was about 52 ng/m3 and constitutes 1.3% of the
total polar organic compounds measured.
|
