title: Analysis of pesticides in dried hops by liquid chromatography-tandem mass spectrometry.
abstract: An analytical method was developed for the determination of eleven agrochemicals [abamectin (as B1a), bifenazate, bifenthrin, carfentrazone-ethyl, cymoxanil, hexythiazox, imidacloprid, mefenoxam, pymetrozine, quinoxyfen, and trifloxystrobin] in dried hops. The method utilized polymeric and NH2 solid phase extraction (SPE) column cleanups and liquid chromatography with mass spectrometry (LC-MS/MS). Method validation and concurrent recoveries from untreated dried hops ranged from 71 to 126% for all compounds over three levels of fortification (0.10, 1.0, and 10.0 ppm). Commercially grown hop samples collected from several field sites had detectable residues of bifenazate, bifenthrin, hexythiazox, and quinoxyfen. The control sample used was free of contamination below the 0.050 ppm level for all agrochemicals of interest. The limit of quantitation and limit of detection for all compounds were 0.10 and 0.050 ppm, respectively.
authors.affiliation: Department of Environmental Toxicology, University of California at Davis, One Shields Avenue, Davis, California 95616, USA. mjhengel@ucdavis.edu
authors.forename: Matt J
authors.initials: MJ
authors.lastname: Hengel
authors.forename: Marion
authors.initials: M
authors.lastname: Miller
mesh_terms: D002853:Chromatography, Liquid; D005506:Food Contamination / Q000032:analysis; D027582:Humulus / Q000737:chemistry*; D010575:Pesticides / Q000032:analysis*; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry
chemical_list: D010575:Pesticides