Determination of a wide range of volatile and semivolatile organic compounds in snow by use of solid-phase micro-extraction (SPME).

Quantification and transformation of organic compounds are pivotal in understanding atmospheric processes, because such compounds contribute to the oxidative capacity of the atmosphere and drive climate change. It has recently been recognized that chemical reactions in snow play a role in the production or destruction of photolabile volatile organic compounds (VOC). We present an environmentally friendly method for determination of VOC and semi-VOC in snow collected at three sites-remote, urban, and (sub-)arctic. A solid-phase micro-extraction (SPME) procedure was developed and (semi-)VOC were identified by gas chromatography with mass spectrometric detection (GC-MS). A broad spectrum of (semi-)VOC was found in snow samples, including aldehydes, and aromatic and halogenated compounds. Quantification was performed for 12 aromatic and/or oxygenated compounds frequently observed in snow by use of neat standard solutions. The concentrations detected were between 0.12 (styrene and ethylbenzene) and 316 microg L(-1) (toluene) and limits of detection varied between 0.11 (styrene) and 1.93 microg L(-1) (benzaldehyde). These results indicate that the SPME technique presented is a broad but selective, versatile, solvent-free, ecological, economical, and facile method of analysis for (semi-)VOC in natural snow samples.