Residue behavior of two novel insecticides in Chaotian pepper and Niujiao pepper during cultivation and processing

To investigate the residue dissipation behavior and processing effects of afidopyropen and broflanilide in peppers with different utilization types and provide a scientific basis for their rational application in pepper production, processing-type Chaotian pepper and fresh-consumption Niujiao pepper were selected as the test materials. A method based on dispersive solid-phase extraction purification combined with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established to analyze the dissipation dynamics of the two pesticides and their related metabolites in peppers. Additionally, the impact of washing, oven-drying, and natural sun-drying on residue levels was assessed. The results showed that the residue dissipation of both pesticides in Chaotian and Niujiao peppers followed first-order kinetics. The initial residues of afidopyropen in Chaotian and Niujiao peppers were 0.250 and 0.102 mg/kg, with half-lives of 3.38 and 6.48 d, respectively. The initial residues of broflanilide were 0.148 and 0.130 mg/kg, with half-lives of 5.73 and 7.37 d, respectively, indicating that both pesticides dissipated more rapidly in Chaotian pepper than in Niujiao pepper. Processing experiments showed that washing reduced residue levels, with processing factors ranging from 0.21 to 0.88 and showing an overall downward trend with prolonged washing time. Both drying treatments resulted in increased residue levels, with PF values ranging from 1.85 to 3.66, all greater than 1. This study provides a reference for the rational application of related pesticides in pepper cultivation and for residue control during processing.