||VOCs in Mexico City ambient air /
Seila, R. L. ;
Lonneman, W. A. ;
Santoyo, M. E. R. ;
Ruiz, J. T.
||Environmental Protection Agency, Research Triangle Park, NC. Atmospheric Research and Exposure Assessment Lab. ;Instituto Mexicano del Petroleo, Mexico City.
|| U.S. Environmental Protection Agency, Atmospheric Research and Exposure Assessment Laboratory,
Volatile organic compounds--Measurement. ;
Air--Pollution--Mexico--Mexico City. ;
Air quality management--Mexico--Mexico City.
Volatile organic compounds ;
Air pollution sampling ;
Air pollution standards ;
Motor vehicles ;
Photochemical reactions ;
Gas chromatography ;
Chemical reactions ;
Carbon 14 ;
Carbon monoxide ;
Mexico City(Mexico) ;
Ambient air ;
Flame ionization detection
||Region 4 Library/Atlanta,GA
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
||6 pages : illustrations ; 28 cm
Mexico City, with nearly 20 million people, 3 million vehicles, and 35,000 industrial businesses, has severe photochemical air pollution. The O3 standard of 0.11 ppm is exceeded over 300 days of the year. Because of the role of VOCs in the production of ozone, a study of the concentration and composition of VOCs in ambient air was undertaken. From March 6 to 26, 1992, 68 ambient air samples were collected on week-days in passivated stainless steel spheres at four sites in Mexico City. Most (52) sampling was in the morning from 6:00-9:00 am, however at 2 sites 16, 12:00-3:00 pm afternoon samples were collected. Ten morning samples were also taken at two upwind sites north of the city. The samples were analyzed by capillary gas chromatography/flame ionization detection (gc/fid) for C-2 to C-14 hydrocarbons. CO and CH4 were also determined. Total non-methane organic compound (TNMOC) concentrations were very high. In the 6-9 am period TNMOC ranged from 1.49 to 6.94 ppm. The afternoon results were lower, ranging from 0.48 to 3.06 ppm. TNMOC at the two boundary sites ranged from 0.16 to 1.64 ppm.
Caption title. In cooperation with Instituto Mexicano del Petroleo. Includes bibliographical references (page 4).