CHEMICAL COMPOSITION OF EXTRACTABLE ORGANIC MATTER OF AIRBORNE PARTICLES IN URBAN AND RURAL ATMOSPHERES OF NORTHERN ALGERIA.

The concentrations of extractable organic fraction of atmospheric particulate matter (PM₁₀) were measured in northern Algeria during summer and autumn 2007. Three monitoring campaigns were done in July, September and October in two urban and one rural areas. The chemical analysis shows that the detected organic groups are n-alkanes, poly- cyclic aromatic hydrocarbons (PAHs), nitrated polycyclic aromatic hydrocarbons (NPAHs) and highly-polar chemicals including caffeine, nicotine and oxygenated-PAHs. In addition to that, the potential sources of pollution were investigated by analyzing the n-alkane carbon preference index (CPI). Also, the selected diagnostic ratios of PAH and NPAH concentrations were studied. The aerial concentrations of the total n-alkanes did not vary widely over the entire period (144 to 170 ng m^-3), while total PAHs ranged from 12 to 24 ng m^-3. Despite their recognized semi-volatile properties caffeine and nicotine, chosen respectively as tracers of recreational drink consumption and tobacco smoke, reached surprisingly high concentration in the air both in summer and autumn. Indeed, they accounted together for ∼12% of the total identified PM components in the Rouiba urban area during summer, and from 37 to 65 % in autumn at all the three sites studied. [ABSTRACT FROM AUTHOR]