Abstract. Particulate matter was collected at an urban site in Göteborg (Sweden) in February/March 2005 and in June/July 2006. Additional samples were collected at a rural site for the winter period. Total carbon (TC) concentrations were 2.1–3.6 μg m−3, 1.8–1.9 μg m−3, and 2.2–3.0 μg m−3 for urban/winter, rural/winter, and urban/summer conditions, respectively. Elemental carbon (EC), organic carbon (OC), water-insoluble OC (WINSOC), and water-soluble OC (WSOC) were analyzed for 14C in order to distinguish fossil from non-fossil emissions. As wood burning is the single major source of non-fossil EC, its contribution can be quantified directly. For non-fossil OC, the wood-burning fraction was determined independently by levoglucosan and 14C analysis and combined using Latin-hypercube sampling (LHS). For the winter period, the relative contribution of EC from wood burning to the total EC was >3 times higher at the rural site compared to the urban site, whereas the absolute concentrations of EC from wood burning were elevated only moderately at the rural compared to the urban site. Thus, the urban site is substantially more influenced by fossil EC emissions. For summer, biogenic emissions dominated OC concentrations most likely due to secondary organic aerosol (SOA) formation. During both seasons, a more pronounced fossil signal was observed for Göteborg than has previously been reported for Zurich, Switzerland. Analysis of air mass origin using back trajectories suggests that the fossil impact was larger when local sources dominated, whereas long-range transport caused an enhanced non-fossil signal. In comparison to other European locations, concentrations of levoglucosan and other monosaccharide anhydrides were low for the urban and the rural site in the area of Göteborg during winter.

The chemical composition of aerosols has been determined in 30 size-resolved samples collected using a Berner lowpressure impactor during two campaigns conducted at a coastal site in the Eastern Mediterranean in July 2000 and in January 2001. Sulfate ðSO 4 accounting for up to 38% of the total fine mass and up to 65% of the total ionic mass during both seasons. On the other hand, nitrate ðNO À 3 Þ; chloride ðCl À Þ; sodium ðNa þ Þ and calcium ðCa 2þ Þ were identified as the main components of the super-micron mode. The ionic organic compounds (including carboxylic, dicarboxylic and ketoacids) were distributed both between sub-micron and super-micron mode, indicating origin from both gas-to-particle conversion and heterogeneous reactions on pre-existing particles. The total water-soluble ionic organic fraction although accounting for only up to 1-2% of both coarse ð> 1 mmÞ and fine ðo1 mmÞ mass fractions, accounts for up to 15% of the organic carbon (OC) mass. NH þ 4 was found to be significantly correlated to non-sea-salt sulfate (nss-SO 2À 4 ), with NH þ 4 =nss-SO 2À 4 molar ratio ranging from 1.3 to 2, the lower ratio associated with transport from the W sector. Chloride depletion was observed mainly during summer and was significantly correlated with NO À 3 concentrations, with a molar ratio of 0.80, indicating the reaction of nitric acid with NaCl as the main source of NO À 3 in the area. Total ionic mass both in the fine and coarse fraction accounted for up to 58% of the total aerosol mass during both seasons. An attempt to perform a mass closure analysis indicates that nss-SO 2À 4 and organic carbon are the main components of the fine fraction with relative contributions of 38% and 16%, respectively. In the coarse fraction, the ionic part accounts for 58%, mineral dust for 32% and the remaining non-identified part of 12-30% could be partly attributed to water. r

Abstract. Sugars and sugar-alcohols are demonstrated to be important constituents of the ambient aerosol water-soluble organic carbon fraction, and to be tracers for primary biological aerosol particles (PBAP). In the present study, levels of four sugars (fructose, glucose, sucrose, trehalose) and three sugar-alcohols (arabitol, inositol, mannitol) in ambient aerosols have been quantified using a novel HPLC/HRMS-TOF (High Performance Liquid Chromatography in combination with High Resolution Mass Spectrometry -Time of Flight) method to assess the contribution of PBAP to PM 10 and PM 2.5 . Samples were collected at four sites in Norway at different times of the year in order to reflect the various contributing sources and the spatial and seasonal variation of the selected compounds.Sugars and sugar-alcohols were present at all sites investigated, underlining the ubiquity of these highly polar organic compounds. The highest concentrations were reported for sucrose, reaching a maximum concentration of 320 ng m −3 in PM 10 and 55 ng m −3 in PM 2.5 . The mean concentration of sucrose was up to 10 times higher than fructose, glucose and the dimeric sugar trehalose. The mean concentrations of the sugar-alcohols were typically lower, or equal, to that of the monomeric sugars and trehalose. Peak concentrations of arabitol and mannitol did not exceed 30 ng m −3 in PM 10 , and for PM 2.5 all concentrations were below 6 ng m −3 .Sugars and sugar-alcohols were associated primarily with coarse aerosols except during wintertime at the suburban site in Elverum, where a shift towards sub micron aerosols was observed. It is proposed that this shift was due to the intensive use of wood burning for residential heating at this site during winter, confirmed by high concurrent concentrations of levoglucosan. Elevated concentrations of sugars in PM 2.5 were observed during spring and early summer at the rural background site Birkenes. It is hypothesized that this was due to ruptured pollen.

Abstract. In the present study, ambient aerosol (PM 10

Ion trap multiple fragmentation mass spectrometry (MS(n)()) combined with high-performance liquid chromatography (HPLC) has been used for the structure elucidation and identification of 2,4-dinitrophenylhydrazone derivatives of carbonyl compounds in ambient air samples. Atmospheric pressure chemical ionization in the negative ion mode was the most suitable detection method. Different measures are described to decrease the MS background originating from the HPLC system. Low-picogram quantities were detectable in extracted mass chromatograms generated from full-scan records. Fragment ions produced by MS/MS allowed identification of substructures of the carbonyls. Detailed fragmentation paths were studied by MS(3) to MS(4) using reference compounds. A fragmentation scheme was established which enabled a structure confirmation and identification with 1-10 ng by HPLC/MS/MS. The identification of a compound coeluting with n-pentanal-DNPH and of a dimerization byproduct are given as examples.