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A complete reliable methodology including several extraction and chromatographic techniques has been developed for the determination of selected organic compounds in atmospheric aerosol particles. Size separated ultrafine particles (Dp ≤ 50nm) and total suspended particles (TSP) were collected in a urban and forest environment. One third of the samples contained TS particles and the rest of the samples were size-separated (30, 40 or 50 nm particles) with a differential mobility analyzer (DMA). Gas chromatography-mass spectrometric and liquid chromatography-mass spectrometric methods were developed for the analysis of the target compounds and the sample pretreatment was shortened by exploiting ultrasonic energy. The investigated compounds included seven amines (average concentrations ranged between 0.1 and 10.9 ng m−3), eight aldehydes (0.1–11.9 ng m−3), two polyols (0.1–81.5 ng m−3) and sixteen acids (0.1–47.2 ng m−3). The whole methodology including sample preparation and analysis methods was carefully validated by comparison of the results obtained with those provided by a conventional extraction method, non-assisted by ultrasound and by standard addition methodology, respectively. There were clear differences, up to two orders of magnitude, in the concentrations of the target compounds in aerosol samples with different sizes collected from an urban and forest environment.

Nonylphenol ethoxylates (NPEOx) are surfactants which are used worldwide and can be transformed in the environment by microorganisms to form nonylphenol (NP). Analysis of these compounds was carried out with micellar electrokinetic capillary chromatography (MEKC). Different parameters such as background electrolyte (BGE) solution, pH, type of surfactant, and sample stacking were optimized. The use of CHES (20 mM, pH 9.1) in combination with 50 mM sodium cholate as a surfactant as BGE solution, together with sample stacking using 50 mM NaCl in the sample and an injection time of 20 s, provided the best separation of the compounds studied. The method was applied to the determination of target analytes in two types of sludge water coming from two steps of a wastewater treatment plant. Liquid–liquid extraction was carried out using toluene as solvent, resulting in recoveries around 100% for all studied analytes. The presence of NPEOxwas observed in the first step of the sludge water treatment, based on migration time and UV spectra. Identification was confirmed using tandem MS. LOQs of the studied compounds were in the range of 12.7 to 30.8 ng/mL, which is satisfactory for the analysis of real wastewater samples.