title: Dissipation, transfer and safety evaluation of emamectin benzoate in tea.
abstract: The dissipation and residue of emamectin benzoate in tea leaves and the residue transfer from tea leaves to tea brew were investigated by modified QuEChERS (quick, easy, cheap, effective, rugged and safe) combined with ultra performance liquid chromatography tandem mass (UPLC-MS/MS). The average recoveries ranged 85.3-101.3% with relative standard deviation (RSD) less than 15%. The limits of quantification (LOQ) were 0.005mgkg(-1) in tea leaves and 0.0004mgL(-1) in brew. Emamectin benzoate dissipated rapidly in tea with half-life (t1/2) of 1.0-1.3days. The terminal residues of emamectin benzoate were less than 0.062mgkg(-1). The leaching rate of emamectin benzoate from freshly-made tea to brew was <5%. The risk of emamectin benzoate at the recommended dosage was negligible to humans depending on risk quotient (RQ) value, that was lower than 1 significantly. This study could provide guidance for the safe use of emamectin benzoate and serve as a reference for the establishment of maximum residue limits (MRLs) in China.
authors.affiliation: Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agricultural, Hangzhou 310008, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agricultural, Hangzhou 310008, China.
authors.forename: Fengjian
authors.initials: F
authors.lastname: Luo
authors.affiliation: Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agricultural, Hangzhou 310008, China.
authors.forename: Xinzhong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agricultural, Hangzhou 310008, China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agricultural, Hangzhou 310008, China.
authors.forename: Zhengyun
authors.initials: Z
authors.lastname: Lou
authors.affiliation: Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agricultural, Hangzhou 310008, China. Electronic address: zmchen2006@163.com.
authors.forename: Zongmao
authors.initials: Z
authors.lastname: Chen
mesh_terms: D028241:Camellia sinensis / Q000737:chemistry*; D002681:China; D002853:Chromatography, Liquid; D005506:Food Contamination; D006207:Half-Life; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000032:analysis; D018515:Plant Leaves / Q000737:chemistry*; D053719:Tandem Mass Spectrometry; D013662:Tea / Q000737:chemistry* / Q000592:standards
chemical_list: D013662:Tea; D007559:Ivermectin; C108024:emamectin benzoate
keywords: Dissipation; Emamectin benzoate; Tea; Transfer; Ultra performance liquid chromatography–tandem mass spectrometry