The temporal and seasonal organic carbon (OC) and elemental carbon (EC) mass concentrations of PM2.5 were studied. The relationship and distribution for the carbonaceous fractions were investigated. The secondary organic aerosols formation and factors affecting carbonaceous fractions in the Monterrey Metropolitan Area (MMA)were identified. The sampling site was impacted mainly by traffic and emissions from a wide range of industrial activities. For the spring, strong correlations between the CO and EC were found in the MMA during the daytime, and weak correlations were found during the nighttime. These results are indicators of primary emission sources, e.g., traffic and industry, and they are in line with the OC/EC ratios obtained that were lower in the daytime than in the nighttime during the spring. For fall, weak correlations were obtained for both the daytime and nighttime. In contrast, no defined tendency was found for the NOx and SO2 correlations.Some strong and weak correlations between the carbonaceous species and gaseous pollutants indicated the presence of anthropogenic emissions. This is an abstract of a paper presented at the AWMA's 107th Annual Conference & Exhibition (Long Beach, CA 6/24-27/2014).
