Abstract: A gas chromatography-mass spectrometry (GC-MS) method was developed for determining metaldehyde residue in various food matrixes including rice, soybean, spinach, tomato, onion, tea, apple and Chinese chestnut. Metaldehyde residue in samples was extracted with acetone-methylene mixture, and then the extracts were purified with LC-NH2/Envi-carb solid phase extraction (SPE) cartridge. The limit of quantification (LOD) of the developed method was 0.01 mg/kg, and the average recoveries and relative standard deviation (RSD) for metaldehyde in samples spiked in the range of 0.01 to 0.5 mg/kg were in the range of 70.5%－111.7% and 4.4%－11.0%, respectively.

Key words: metaldehyde, plant-derived food, residue, gas chromatography-mass spectrometry (GC-MS)