International Science Community Association Research Journal of Recent Sciences 2277 - 2502 6 6 2017 06 2 Characterization of carbonaceous aerosols in fine and coarse particles at Agra, India 1 4 EN Pachauri Tripti 1 Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra 282 110, India Lakhani Anita 2 Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra 282 110, India Kumari K. Maharaj 3 Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra 282 110, India > Research Paper 2017 4 3 2017 06 2 A continuous measurement of organic carbon (OC) and elemental carbon (EC) in PM2.5 and PM10 was carried out at Agra situated in North central region of India. PM2.5 and PM10 samples were collected from Jan to Dec 2012 and were analyzed for OC and EC using thermal optical transmittance (TOT) protocol. The results showed that the mass concentrations of PM2.5 and PM10 ranged from 25.6 to 164.6µg/m3¬ and 45.5 to 490µg/m3¬ respectively. Both OC and EC exhibited a clear seasonal pattern with highest concentration observed in winter followed by summer and monsoon which may be due to the combined effect of changes in emission rates and different meteorology in various seasons. TCA accounted for an averaged 51.3% of PM2.5 mass and 40.4% of PM10 mass. This indicates that the carbonaceous fraction nearly accounted for more than one third of PM10 mass and about half of PM2.5 mass which shows that fine particles are enriched with carbonaceous species. The annual average OC/EC ratio was found to be 6.6 ± 2.8 and 6.9 ± 3.6 for PM2.5 and PM10 respectively. This ratio is similar to the ratio reported for biomass burning emissions. The SOC concentrations were found to be higher during winter season in both PM2.5 and PM10. During winter season, SEM/EDX analysis revealed the dominance of carbonaceous particles whose origin is mainly anthropogenic in nature. Copyright@ International Science Community Association