Dynamics of Chlorpyrifos -Methyl Residues on Cabbage and Soil

A gas liquid chromatographic method for determination of dynamics of di ssipation and final chlorpyrifos -methyl residues in and on cabbage and soil was describ ed.The cabbage was applied with 40%e mulsification of the insecticide at a dose of 720g ·hm -2 and it has been found the initial residues in and on cabbage and soil were 5.82and 2.12mg ·kg -1 ,respectively.Furthermore,the half -lives for the insecticide r esidue in and on the leaf and soil were0.4and 1.4days,respectively.The f inal residue on the cabbage was 0.02mg ·kg -1 for the sample receiving 3times of ap plications and at last application with an interval of 7days from harvest.