Trends in alkanes and PAHs in airborne particulate matter from Oporto and Vienna: identification and comparison

A total of 56 weekly samples from Oporto and 40 from Vienna were collected and analysed, for 23 n-alkanes and 16 polycyclic aromatic hydrocarbons (PAH ), by CC-MS after extraction with a toluene/methanol mixture. Total and ele mental carbon were in the same range of values for both sampling sites. Alt hough parts of the spectrum of species in both sampling sites were constant over the sampling period there is no evidence for suggesting a universal t racer for alkanes. For both Oporto and Vienna, Principal Component Analysis (PCA) identified two PCs and in both cases the first PC contained only PAH s while the second contained only alkanes. This separation between alkanes and PAHs and the observation of an alternating pattern with higher concentr ations of odd carbon numbered from C-27 to C-30 (natural emissions from bio logical origin) is believed to result from a separation between anthropogen ic and biological contributions associated with the first and second PC, re spectively. (C) 1999 Elsevier Science B.V. All rights reserved.