摘要:The analytical method for multi-residues of chlorinated phenoxy agricultural chemicals (2, 4-D, 2, 4, 5-T and 2, 4, 5-TP) in several kinds of fruits and vegetables was investigated. These compounds could be analyzed by gas chromatography with ECD (ECD-GC) after methylation of the sample extract with diazomethane followed by clean-up on silica gel column. The minimum detectable residues of 2, 4-D, 2, 4, 5-T and 2, 4, 5-TP in fruits and vegetables (e.g. apple, egg apple, lemon and tomato) by ECD-GC were 0.005 ppm, 0.001 ppm and 0.0005 ppm, respectively. 2, 4-D separated from a lemon sample was methylated with diazomethane and confirmed by comparing the mass spectrnm and mass chromatograms obtained by GC-MS with those of the methyl ester of the authentic sample. Furthermore, in the surveillance of 2, 4-D residues in the citrus fruits imported from U.S.A. in 1979 to 1981, 2, 4-D was never detected in all of grapefruit and navel orange samples, but it was detected at the levels of 0.010 to 0.21 ppm in all of lemon samples.