Comparative Study of Gas and Particulate Phase Concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) at Two Sites in Agra

Polycyclic Aromatic Hydrocarbons (PAHs) are present in both the gas and particulate phase in the atmosphere. Samples of aerosols were collected simultaneously at a rural and traffic dominated site in Agra during winter season to measure the gas and particulate phase concentrations of PAHs. An air sampler (Model TE-1000X) was used for sampling. To collect the particulate PAHs quartz micro fiber filter papers were used and polyurethane foam plugs were used for the gas phase. Samples were extracted in a mixture of dichloromethane (DCM) and n-hexane (4:1 ratio). The 16 priority PAHs were analyzed by Gas Chromatograph -Mass Spectrophotometer (GC-MS) (Bruker Scion SQ). Gas + particulate phase concentration of individual PAH ranged from 38 to 4112 ng m−3 at the traffic site while it ranged from 18 to 1316 ng m−3 at the rural site. The partitioning of PAHs between both the gas and particulate phase was investigated. The influence of meteorological parameters on the gas-particle partitioning of these compounds has been studied.