Abstract: A gas chromatography-tandem mass spectrometry (GC-MS/MS) method was developed for the simultaneous determination of di (2-ethylhexyl) terephthalate and tris (2-ethylhexyl) trimellitate in edible oils. The plasticizers in the samples were extracted with acetonitrile. The extract was purified by freezing at -20 ℃, and determined by GC-MS/MS in selective reaction monitoring mode. For the two compounds, the limit of detection and limit of quantification were 0.03 mg/kg and 0.1 mg/kg, respectively, and the linear range was 0.1-10 mg/kg. The recoveries of the two compounds ranged from 81.04% to 108.31% at three spiked levels (0.1, 0.3, and 1.0 mg/kg), and the relative standard deviation ranged from 0.70% to 9.91%. The method is simple, accurate, and suitable for the determination of di (2-ethylhexyl) terephthalate and tris (2-ethylhexyl) trimellitate in edible oils.

Key words: gas chromatography-tandem mass spectrometry (GC-MS/MS), di-2-ethylhexyl terephthalate, tris (2-ethylhexyl) trimellitate, edible oil