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Attempts have been made in the present study for ascertaining the content of atmospheric polycyclic aromatic hydrocarbons (PAHs) using passive biosamplers in preference to conventional air sampling methods. Mechanical stirring, sonication, Soxhlet technique and microwave-assisted Soxhlet extraction (MASE) were employed to extract PAHs from an evergreen plant (Murraya paniculata) leaves (having long life-span) sampled from polluted places of South Kolkata, India, with dense population. Effects of extraction methods and operational parameters on the recovery levels of PAHs were also investigated. Purified extracts, acquired through adsorption chromatography, were subjected to GC-MS and HPLC-UV analyses for qualitative and quantitative assessment of PAHs. Spatio-temporal distribution of accumulated PAHs across the sampling sites was monitored over premonsoon, postmonsoon and winter supported by pollutant source characterization. The results displayed that the extraction yields of Soxhlet and MASE were highest among the four techniques. Conditions of extraction with toluene for 6 h were found to be most favourable for PAHs. Total concentrations of PAHs in the foliar samples varied from 200.98 ± 2.72−550.79 ± 10.11 µg g− 1 dry weight, highest values being recorded in the samples of Exide More (EXM) because of daylong inexorable traffic flow/crowding increasing the burden of ambient PAHs. Widespread changes in meteorology exerted influence on seasonal concentrations of PAHs in plant leaves. Foliar accretion of PAHs differed in the study sites with diverse sources of emission from motor vehicles, fossil fuel and biomass burning along with other human interferences.

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