title: Analyses of pesticide residues in fruit-based baby food by liquid chromatography/electrospray ionization time-of-flight mass spectrometry.
abstract: A liquid chromatography/electrospray ionization time-of-flight mass spectrometry (LC/ESI-TOFMS) method has been developed for the determination of 12 pesticides (namely, carbendazim, thiabendazole, imazalil, tridemorph, triadimefon, bitertanol, prochloraz, flutriafol, myclobutanil, iprodione, diphenylamine and procymidone) in fruit-based baby food (multi-fruit jars and juices intended for infant consumption). The developed method consists of a sample treatment step based on liquid-liquid extraction using acetonitrile, followed by a clean-up step based on dispersive solid-phase extraction (SPE) with a primary-secondary amine (PSA). Multi-fruit and apple juices were processed by a SPE procedure using Oasis HLB cartridges. Subsequent identification and quantitation was accomplished by LC/ESI-TOFMS analysis: the confirmation of the target pesticides was based on accurate mass measurements of selected ions (protonated molecules ([M+H]+) and fragment ions). Confirmation studies were accomplished at low concentration levels (10 microg kg-1) and accuracy errors lower than 2 ppm were obtained in most cases. Baby food extracts spiked at 10 microg kg-1 fortification level yielded average recoveries in the range 78-105% with relative standard deviations less than 10% for most of the analytes. Limits of detection (LODs) were between 0.1 and 4 microg kg-1 depending on the pesticide studied. Finally, the proposed method was applied to a total of 33 baby food samples from Spain and the United Kingdom. Although imazalil, thiabendazole and carbendazim were detected in a high number--over 60%- of baby food samples, none of the samples tested were found to be above the 0.01 mg kg-1 EU standard.
authors.affiliation: Department of Physical and Analytical Chemistry, University of Jaén, 23071 Jaén, Spain.
authors.forename: Bienvenida
authors.initials: B
authors.lastname: Gilbert-López
authors.forename: Juan F
authors.initials: JF
authors.lastname: García-Reyes
authors.forename: Pilar
authors.initials: P
authors.lastname: Ortega-Barrales
authors.forename: Antonio
authors.initials: A
authors.lastname: Molina-Díaz
authors.forename: Amadeo R
authors.initials: AR
authors.lastname: Fernández-Alba
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D005240:Feasibility Studies; D005638:Fruit / Q000737:chemistry*; D006801:Humans; D007223:Infant; D007225:Infant Food / Q000032:analysis*; D015394:Molecular Structure; D010573:Pesticide Residues / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D010573:Pesticide Residues