engleski

Atmospheric deposition of organic compounds

The atmosphere is a carrier by which some natural and anthropogenic pollutants are transported. Deposition events are the most important mechanisms that remove organic compounds from the atmosphere to terrestrial and aquatic ecosystems. A method based on solid phase extraction (SPE), gas chromatography-mass spectrometry (GC-MS/MS) and gas chromatography with electron capture detector (GC-ECD) was developed for the determination of polycyclic aromatic compounds (PAHs) and polychlorinated biphenyls (PCBs) in atmospheric deposition samples. PAH compounds (fluoranthene (FLU), pyrene (PYR), benz(a)anthracene (BaA), chrysene (CHRY), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(j)fluoranthene (BjF), benzo(a)pyrene (BaP), benzo(e)pyrene (BeP), indeno(1, 2, 3- cd)pyrene (IP), dibenz(a, h)anthracene (DahA) and benzo(g, h, i)perylene (BghiP)) were analysed by GC-MS/MS and six indicator PCB congeners (PCB-28, PCB-52, PCB-101, PCB-138, PCB-153 and PCB-180) were analysed by GC-ECD equipped with two micro electron-capture detectors and two gas chromatographic columns. Solid phase extraction on silica sorbent was suitable for accumulation of PAHs and PCBs from deposited matters. The extraction procedure was based by passing the whole sample volume through a silica cartridge with dichloromethane and n-hexane (1:1, v/v) as the eluting solvents. Prior to analysis, the eluate was dried with sodium anhydrous sulphate and evaporated under a stream of nitrogen to 2 mL. The method was applied for analysis of the 12 PAHs and six indicator PCBs in monthly total deposited matters samples collected by bulk method at an urban background station in Zagreb, Croatia during 2018. The levels and occurrence of PCBs corresponded to global environmental pollution with the highest PCB deposition rate determined in December. During the measurement period, the deposition rates of Σ12PAHs varied between 132.2 ng m-2 d-1 and 698.6 ng m-2 d-1.

Bulk ; PAH ; PCB ; Total deposited matter

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