Sources, formation, reactivity and quantification of polycyclic aromatic hydrocarbons (PAH) in atmosphere.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants whose environmental behavior has been investigated for more than 20 years, The widespread occurrence of PAHs is largely due to the formation and releasing during incomplete combustion of petrol, oil, coal and wood, The atmosphere is a major pathway for transport and deposition of natural and anthropogenic PAHs and other organic chemicals, Motor vehicles are important sources of atmospheric PAHs. They are also emitted by aluminum production plant, forest fires, residential wood combustion, coke manufacturing, power generation and waste incineration, PAHs and derivatives, e.g. nitro-PAHs (NPAHs) and oxi-PAHs, constitute important class of compounds because several are known carcinogenic in animals and mutagenic in bacteria agents, Specially nitroarenes were found to be powerful direct acting mutagens in the Ames-Salmonella test, PAHs may react with NOx or N2O5 in atmosphere, giving NPAHs, being an important route for nitrenes formation, Degradation of PAHs adsorbed on aerosols or in vapor-phase and the dry deposition or wet deposition are important sink for such compounds in the atmosphere, The determination of PAHs and their derivatization products in ambient air is therefore of considerable importance to the characterization of air and life quality.