Functional and non functional particulate hydrocarbons in urban, rural and forest atmospheres of Northern Algeria

Airborne particulates were collected daily during three year seasons by using medium-volume aspirating systems equipped with PM10 inertial impactors. The organic fraction was solvent extracted with soxhlet, fractioned and cleaned-up through column chromatography, then processed by gas chromatography combined with flame ionisation and mass spectrometry detectors. Chemical analyses allowed characterising a set of groups of compounds, namely n-alkanes, n-alkanoic acids, dicarboxylic acids, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, and highly-polar chemicals. Besides that, the potential sources of pollution were investigated by analysing the n-alkane carbon preference index and selected diagnostic ratios among PAH and NPAH concentrations. Total concentrations of n-alkanes varied widely over the study period (from 48 to 170 ng m−3); PAHs behaved similarly (2 ÷ 24 ng m−3). Caffeine and nicotine accounted together for ∼12% of all identified PM components in the Rouiba urban area during summers and this percentage raised up to ~65% in autumn 2007.