[Determination of phthalic acid esters in soil by gas chromatography-tandem mass spectrometry]

A method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the determination of phthalic acid esters (PAEs) in soil. The soil sample was extracted by dichloromethane-acetone (1: 1, v/v) with an ultrasonic instrument, and the extract was cleaned up with a Florisil column. The identification and quantification of the analytes were carried out in the multiple reaction monitoring (MRM) mode after the GC separation on an HP-5MS column (30 m x 0.25 mm x 0.25 microm). The eight point calibration curves showed a good linearity for all the congeners (0.997 3 - 0.997 6). The limits of detection (LODs) ranged from 0.1 to 0.5 microg/kg. The relative standard deviations (RSDs) were not more than 14.3% and the spiked recoveries were in the range of 72.9% - 106.2%. The developed analytical method is rapid and accurate, and suitable for the determination of PAEs in soil.