Study on the Residues of Dimethoate in Chinese Cabbage (Brassica campestris)

The residues of dimethoate in Chinese cabbage (Brassica campestris) were studied by the gas chromatography. The results showed that the metabolic velocity of dimethoate in Chinese cabbage was very slow.The residues of dimethoate were higher than the safe standard in five days after pouring dimethoate on the samples in natural condition and in six days under plastic cover. The man made rainfall had great effect on the residues of dimethoate. The three different washing methods had no obvious effect on decreasing residues of the pesticide to the safe level.