Determination of procymidone in sicilian olive oils by gas chromatography-mass spectrometry (HRGC-MS)

The aim of the present research was to develop an accurate, precise and repeatable method to give information about the concentration of procymidone in olive oils. This pesticide has been used for years as fungicide in agriculture mainly to prevent botrytis cinerea in vineyards, but its uses are not known for the treatment of olive diseases. Procymidone in the studies samples was extracted with acetonitrile; The extract was concentrated and then analyzed by gas chromatography-mass spectrometry (HRGC-MS), using a 5% phenyl-95% methylpolysiloxane-coated fused-silica capillary column. The detection and quantification limits were equal to 0.08 and 0.24 mg/kg, respectively, with linear calibration curve from 0.1 mg/l. Absolute recovery was 93.03% with relative standard deviation of 3.06%. The proposed method was validated with satisfactory results also for the repeatability within a day and between days. Finally, it was applied to analyze 14 Sicilian olive oil samples. Procymidone was identified in 12 samples, although the levels found were very low; In general, the presence of this contaminant in olive oil could result from inadequate treatment or from a phenomenon of "drift" when olive trees are located near areas with vines. Therefore, controlling the levels of procymidone in olive oil also appears to be important when product quality should be ensured.