title: Evaluation of an analytical methodology using QuEChERS and GC-SQ/MS for the investigation of the level of pesticide residues in Brazilian melons.
abstract: A multiresidue method based on the sample preparation by modified QuEChERS and detection by gas chromatography coupled to single quadruple mass spectrometers (GC-SQ/MS) was used for the analysis of 35 multiclass pesticides in melons (Cucumis melo inodorus) produced in Ceara-Brazil. The rates of recovery for pesticides studied were satisfactory (except for the etridiazole), ranging from 85% to 117% with a relative standard deviation (RSD) of less than 15%, at concentrations between 0.05 and 0.20 mg kg(-1). The limit of quantification (LOQ) for most compounds was below the MRLs established in Brazil. The combined relative uncertainty (Uc) and expanded uncertainty (Ue) was determined using repeatability, recovery and calibration curves data for each pesticide. Analysis of commercial melons samples revealed the presence of pesticides bifenthrin and imazalil at levels below the MRLs established by ANVISA, EU and USEPA.
authors.affiliation: Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, Rua Humberto Monte, S/N Campus do Pici, Bl. 935, CEP 60451-970 Fortaleza, CE, Brazil.
authors.forename: Jonas
authors.initials: J
authors.lastname: da Silva Sousa
authors.forename: Rubens Carius
authors.initials: RC
authors.lastname: de Castro
authors.forename: Gilliane
authors.initials: G
authors.lastname: de Albuquerque Andrade
authors.forename: Cleidiane Gomes
authors.initials: CG
authors.lastname: Lima
authors.forename: Lucélia Kátia
authors.initials: LK
authors.lastname: Lima
authors.forename: Maria Aparecida Liberato
authors.initials: MA
authors.lastname: Milhome
authors.forename: Ronaldo Ferreira
authors.initials: RF
authors.lastname: do Nascimento
mesh_terms: D001938:Brazil; D019662:Cucurbitaceae / Q000737:chemistry*; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D007093:Imidazoles / Q000032:analysis / Q000302:isolation & purification; D057230:Limit of Detection; D010573:Pesticide Residues / Q000032:analysis* / Q000302:isolation & purification*; D011722:Pyrethrins / Q000032:analysis / Q000302:isolation & purification; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D007093:Imidazoles; D010573:Pesticide Residues; D011722:Pyrethrins; C099952:bifenthrin; C017435:enilconazole
keywords: GC-SQ/MS; Melon; Multiresidue; QuEChERS; Uncertainty