A temporal/spatial characterization of hazardous air
pollutants in the central
Shar Samy
Graduate Student,
Canister-based VOC sampling in the winters of 2003/2004 was
conducted in the central
For the 2003 sampling, Toluene was found to have the highest overall average ambient concentration of 1.36 parts per billion by volume (ppbv), followed by Benzene (0.84 ppbv), m,p-Xylene (0.38 ppbv), and Ethylbenzene (0.27 ppbv). Overall daytime averages were significantly higher than nighttime averages, and a daily double peak in concentrations was observed in proportion to the local morning/evening rush-hour commutes. The 2004 concentrations were higher for Benzene and Toluene, with similar diurnal trends. These results may have been a function of the different temporal/spatial 2004 sampling regime, relative to 2003.
Source correlation, dispersion, and major sinks are briefly
discussed and evaluated. Daily anthropogenic activities such as auto-traffic
volume and solvent use, do appear to significantly
impact the urban ambient air quality in