Monitoring of priority pesticides using SPME (solid phase microextraction) in river water from Greece

A solid phase microextraction (SPME) method was applied for the extended monitoring survey of priority pesticides for the European Union, for 12 months, in Kalamas River water samples (Epirus region in northwestern Greece) to determine their concentration levels and seasonal variations. For this purpose, polydimethylsiloxane-coated fiber has been utilized. The samples were screened using gas chromatography with flame thermionic detection. Detections were confirmed by gas chromatography-mass spectroscopy (MS). The most frequently detected pesticides were some of the more commonly used herbicides such as EPTC, trifluralin, atrazine, desethylatrazine, terbuthylazine, alachlor and insecticides such as carbofuran, diazinon, disulfoton, methyl parathion, ethyl parathion, fenthion and ethion. Concentrations of individual compounds ranged from 0.050 to 0.3 μg/L. Greater pesticide concentrations occurred during application seasons. A comparison with a well established SPE (C18-disks) procedure was performed for the samples of high season application (May-September) to confirm the effectiveness of the SPME technique. The results demonstrate the suitability of the SPME method for routine screening multi-residue analysis in natural waters.