Secondary organic aerosol tracers and related polar organic compounds between urban and rural areas in the Eastern Mediterranean region: source apportionment and the influence of atmospheric oxidants

Abstract

Fine particle samples were collected during summer at an urban (LIM) and a rural/background (AGM) site of Cyprus. They were analyzed for pinene and isoprene secondary organic aerosol (PSOA-ISOA) tracers,...

Hybrid Targeted/Untargeted Screening Method for the Determination of Wildfire and Water-Soluble Organic Tracers in Ice Cores and Snow

“…Among the 10 compounds with the highest intensities (≥3 × 10 8 ), four were identified at Level 4, two were identified at Level 2, while four were identified at Level 1 through the comparison with reference standards (Table 2). Those identified at Level 1 were typical dicarboxylic acids, such as 38 which was also found in the sample. We also identified levulinic acid (C 5 H 8 O 3 ), which is a γ-ketoacid.…”

Analytical methodologies for oxidized organic compounds in the atmosphere

“…The first-generation products have been found to form under atmospheric conditions with OH or ozone and at lower NO x concentrations, while an increase in NO x concentrations has yielded more higher-generation products. 34,44 In smog chamber experiments by Müller et al , 44 cis -pinonic acid was demonstrated to react with OH radicals, as pinic acid was not observed to produce 3-MTBCA. Occurring in the gas phase, cis -pinonic acid was observed to have higher volatility, and its fraction increased at higher chamber temperatures leading to higher 3-MBTCA concentrations.…”

“…13,33 Ozonolysis also contributes to isoprene oxidation in which typical products are formed, albeit less compared to the OH-initiated reactions. 34…”

“…The most commonly monitored IEPOX derivatives have been 2-methylerythritol and 2-methylthreitol (known as 2-methyltetrols, 2-ME), 5,26,27,34 which are formed at low NO x concentrations by the addition of water with acidic catalysis. Recently, 9,36 oxidation products of 2-MEs have been detected and identified, namely 2-methyltartaric acids, 2-methylerythronic acid, 2-methylthreonic acid, and their 3-methyl isomers.…”

“…49,50 Aromatic compounds and unsaturated hydrocarbons containing a double bond react with ozone and OH. 19,34,49–51 Increased concentrations of anthropogenic markers (Fig. S4†) have generally been observed in the winter when biomass burning and other anthropogenic activities are more common.…”