Paper ID : 20100703 Emission Characterization of Organic Compounds from Combustion of Fossil Fuels and Biomass in Delhi: Assessment of Associated Health Risks

Description of the Paper The growing urbanization and industrialization has considerably deteriorated the air quality of major cities in the World. Organic pollutants such as Polycyclic Aromatic Hydrocarbons (PAHs) and Volatile Organic Compounds (VOCs) are of special concern as they are ubiquitous in nature and some of them are among the strongest known carcinogenic and mutagenic species. Combustion generated emissions from automobiles along with biomass fuels are the dominant contributors of ambient PAHs and VOCs in the environment. The main objective of this study is to monitor PAHs and VOCs from exhaust of automobiles (private vehicles, light and heavy commercial vehicles) and biomass being used as a source of energy in the National Capital region of Delhi to estimate the contribution of these emissions from transport and domestic sector and also to assess their health effects. Applications High concentrations of PAHs and VOCs in ambient air of urban areas stress the need to control PAH and VOC emissions due to their toxic and carcinogenic nature. VOCs are the major gaseous precursors; their vapours also actively participate in photochemical reactions and contribute to the formation of secondary aerosols. Conclusion PAHs are higher from the exhaust of diesel fuelled vehicles than gasoline fuelled vehicles. The most common PAHs associated with vehicle exhausts are pyrene, phenanthrene, acenaphthylene, fluoranthene, benzo[b]fluoranthene, benzo[ghi]perylene and Indeno[123-cd]pyrene. The predominant PAH from various biomass fuels are fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene. The most abundant VOCs from vehicle exhausts and biomass combustion are benzene, toluene, ethyl benzene and xylene followed by 1,2,4- and 1,3,5trimethylbenzene, styrene and 1,4-dichlorobenzene. Compared with other metropolitan cities, Delhi has much higher levels of PAHs and VOCs in the ambient atmosphere. The results of this study underlined the importance of local emission sources, especially vehicular traffic and usage of biomass in domestic sector. Technical Contribution The extent of annual emissions, thus estimated, forms the basis to devise a strategy to minimize such emissions & assessing policy enforced by the government for the improvement of air quality and hence better livelihood. Such studies are of particular importance for developing countries where rapid urbanization and economic growth has lead to the increase in vehicle density and fuel consumption in large metropolitan cities.