title: Dissipation kinetics of emamectin benzoate and lufenuron residues in cabbage grown under field conditions.
abstract: Residue analysis of emamectin benzoate and lufenuron in cabbage matrices and soil was developed using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and ultra high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The samples were extracted with 1% acetic acid in acetonitrile (v/v) or 1% acetic acid in acetonitrile/water (5:1, v/v) and cleaned up by dispersive solid-phase extraction. Mean recoveries and relative standard deviations (RSDs) in all samples ranged 87.8-100.0 % and 3.6-12.6% for emamectin benzoate and 87.8-104.8 % and 6.2-11.5% for lufenuron, respectively. The validated method was used to evaluate the dissipation rate of emamectin benzoate and lufenuron in cabbage and soil as well as the residual levels in harvested cabbage and soil at different preharvest intervals (PHI). The half-lives of emamectin benzoate and lufenuron were 1.08-2.70 and 1.74-5.04 days in cabbage, and 1.42-4.01 and 0.94-6.18 days in soil, respectively. The terminal residues were below the China maximum residue limits (MRLs) at 3 days for emamectin benzoate (0.1 mg kg(-1)) and European Union MRLs at 5 days for lufenuron (0.5 mg kg(-1)), which suggested that 5 days could be recommended as the PHI for the commercial formulation of emamectin benzoate and lufenuron application in the Chinese cabbage field.
authors.affiliation: Lab of Pesticide Residues and Environmental Toxicology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China.
authors.forename: Bizhang
authors.initials: B
authors.lastname: Dong
authors.affiliation: Lab of Pesticide Residues and Environmental Toxicology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Lab of Pesticide Residues and Environmental Toxicology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China. jyhu@ustb.edu.cn.
authors.forename: Jiye
authors.initials: J
authors.lastname: Hu
mesh_terms: D019342:Acetic Acid / Q000737:chemistry; D000097:Acetonitriles / Q000737:chemistry; D001549:Benzamides / Q000032:analysis*; D001937:Brassica / Q000737:chemistry*; D002138:Calibration; D002681:China; D002853:Chromatography, Liquid; D004784:Environmental Monitoring / Q000379:methods*; D006207:Half-Life; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000032:analysis; D007700:Kinetics; D010573:Pesticide Residues / Q000032:analysis*; D010936:Plant Extracts / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry; D005466:Fluorocarbons
chemical_list: D019342:Acetic Acid; D000097:Acetonitriles; D001549:Benzamides; D007559:Ivermectin; D010573:Pesticide Residues; D010936:Plant Extracts; D012987:Soil; D012989:Soil Pollutants; C070364:fluphenacur; D005466:Fluorocarbons; C108024:emamectin benzoate; C032159:acetonitrile
keywords: Cabbage; Dissipation; Emamectin benzoate; Lufenuron; Residues