title: Validation and uncertainty analysis of a multiresidue method for 67 pesticides in made tea, tea infusion, and spent leaves using ethyl acetate extraction and gas chromatography/mass spectrometry.
abstract: A rapid, specific, and sensitive multiresidue method to determine 67 pesticides in made tea, tea infusion, and spent leaves was developed and validated for routine analysis by GC/MS with an approximately 29 min GC run time. The method was reproducible (HorRat < 0.5 at 50 ng/g) when validated at 50 and 100 ng/g. The samples were extracted with ethyl acetate-cyclohexane (9 + 1, v/v), and the extracts were cleaned up by dispersive SPE with primary-secondary amine sorbent + graphitized carbon black + Florisil. The recoveries of all the pesticides were within 70-120% with an RSD of < 20% at 50 ng/g and R2 > 0.99. The matrix effect on the signals of the compounds was corrected by using matrix-matched calibration standards. The LOQ met the requirements of the maximum residue limits for pesticides in tea as recommended by the European Union.
authors.forename: Bappaditya
authors.initials: B
authors.lastname: Kanrar
authors.forename: Sudeb
authors.initials: S
authors.lastname: Mandal
authors.forename: Anjan
authors.initials: A
authors.lastname: Bhattacharyya
mesh_terms: D000085:Acetates / Q000737:chemistry*; D002138:Calibration; D003510:Cyclohexanes / Q000737:chemistry; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D010573:Pesticide Residues / Q000032:analysis*; D010575:Pesticides / Q000032:analysis; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry; D013662:Tea / Q000378:metabolism*; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D000085:Acetates; D003510:Cyclohexanes; D010573:Pesticide Residues; D010575:Pesticides; D012997:Solvents; D013662:Tea; D014867:Water; C506365:Cyclohexane; C007650:ethyl acetate