Pesticide Residue Content in Vegetable Bases of Lhasa City

[Objectives] To understand the quality safety of vegetables produced in vegetable planting bases around Lhasa City. [Methods] Four vegetable planting bases in the east, west, south, and north of Lhasa City were randomly selected for testing using rapid measuring instrument for agricultural residues and solid-phase microextraction-gas chromatography-mass spectrometer, with 120 vegetable samples selected. The testing samples included seven categories: green leafy vegetables, eggplants, melons, onions and garlic, root vegetables, beans, and fungi, totaling 29 types of vegetables. The samples were tested for 8 common prohibited and restricted pesticides in organic phosphorus and carbamate esters, including methamidophos, parathion, methyl parathion, monocrotophos, isocarbophos, methamidophos, aldicarb, and carbofuran. [Results] The pesticide inhibition rate of 6 kinds of vegetables detected by the rapid measuring instrument for agricultural residues was relatively high, with green leafy vegetables being the majority, reaching over 25%. By further establishing a solid-phase microextraction-gas chromatography-tandem mass spectrometry method, the accuracy of the data was verified experimentally. The experimental results indicated that the inhibition rate of vegetable samples in this experiment did not exceed 15%, and it was determined as a pollution-free vegetable. [Conclusions] According to the restriction standard of national pesticide use, the inhibition rate of vegetable samples was less than or equal to 40%, indicating that the quality of vegetables was qualified.