Survey of Four Groups of Cumulative Pesticide Residues in 12 Vegetables in 15 Provinces in China.

The present study investigated the concentrations of residues of four groups of pesticides in the People's Republic of China: organophosphorus, carbamate, pyrethroid, and triazine pesticides. Twenty-six pesticides were examined using gas chromatography-tandem mass spectrometry and liquid chromatography-tandem mass spectrometry in 2,169 samples of 12 typical vegetables collected from 15 provinces in China. The results showed that 908 (41.9%) samples were positive, with 133 (6.1%) samples exceeding the limit legal in China. Leafy vegetables showed higher positive rates than fruits and root vegetables. Organophosphorus, carbamate, pyrethroid, and triazine pesticides were found in 11.8, 7.7, 13.9, and 10.9% of the samples, respectively, which provided important information on current concentrations of cumulative assessment group pesticide residues for vegetables in China. Of the positive samples, a slight violation rate of 1.9% for the organophosphorus pesticide category exceeded China's maximum residue limits. Positive rates for chlorpyrifos in celery, pak-choi, and leeks were higher, but fewer exceeded China's maximum residue limits.