Abstract:

An analytical method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was presented for the determination of metalaxyl residue in 2 animal-derived foods, namely pigeon meat and duck kidney and 6 plant-derived foods, namely multiple vegetable juice, apple, sweet orange, grape, lemon and kiwifruit. The analyte was quantified by the external standard method. Mean spike recoveries of metalaxyl ranged from 95.9% to 102.0% for animal-derived foods (represented by duck kidney), and 116.4% and 141.0% for plant-derived foods (represented by sweet orange), with relative standard deviations ranging from 2.13% to 12.7% for duck kidney and from 0.37% to 4.09% for sweet orange. The limits of detection of the method for duck kidney and apple were 0.002 mg/kg and 0.001 mg/kg, respectively.

Key words: metalaxyl, liquid chromatography-tandem mass spectrometry (LC-MS/MS), food, pesticide residue