title: Dissipation kinetics of organophosphorus pesticides in milled toasted maize and wheat flour (gofio) during storage.
abstract: The dissipation/degradation of the pesticides dimethoate, terbufos, disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio) during three months of storage. Their dissipation kinetics and residual levels were determined, as well as their possible decomposition into some of their main transformation products (disulfoton sulfoxide, terbufos sulfone and disulfoton sulfone). For this purpose, pesticide-free milled toasted maize and wheat samples were spiked with the pesticides, and they were then stored in the darkness at ambient temperature in a closed container to simulate current storage conditions of such packed food. A multiresidue analysis based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was performed for the simultaneous determination of these pesticides and their metabolites. After three months of storage, the dissipation of residues ranged between 34% (pirimiphos-methyl) and 86% (disulfoton) for maize gofio and between 69% (terbufos) and 92% (disulfoton and pirimiphos-methyl) for wheat gofio. The results demonstrated that the degradation was slower in gofio than in wheat gofio and that none of the selected metabolites were detected in any of the samples. Dissipation curves of all studied pesticides fitted to a first-order decay curve in both types of cereals.
authors.affiliation: Departamento de Ciencias Básicas, Facultad de Ingeniería, Universidad EAN, Calle 79 n° 11-45, Bogotá D.C., Colombia.
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: González-Curbelo
authors.affiliation: Departamento de Química, Unidad Departamental de Química Analítica, Facultad de Ciencias, Universidad de La Laguna (ULL), Avda. Astrofísico Fco. Sánchez, s/n°, 38206 San Cristóbal de La Laguna, Spain.
authors.forename: Bárbara
authors.initials: B
authors.lastname: Socas-Rodríguez
authors.affiliation: Instituto de Investigación en Ciencias de Alimentación (CIAL-CSIC), Nicolás Cabrera 9, Campus Cantoblanco UAM, 28049 Madrid, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Herrero
authors.affiliation: Instituto Universitario de BioOrgánica Antonio González, Universidad de La Laguna (ULL), Avda. Astrofísico Fco. Sánchez, 2, 38206 San Cristóbal de La Laguna, Tenerife, Spain.
authors.forename: Antonio V
authors.initials: AV
authors.lastname: Herrera-Herrera
authors.affiliation: Departamento de Química, Unidad Departamental de Química Analítica, Facultad de Ciencias, Universidad de La Laguna (ULL), Avda. Astrofísico Fco. Sánchez, s/n°, 38206 San Cristóbal de La Laguna, Spain. Electronic address: jhborges@ull.edu.es.
authors.forename: Javier
authors.initials: J
authors.lastname: Hernández-Borges
mesh_terms: D002849:Chromatography, Gas / Q000379:methods; D002523:Edible Grain / Q000737:chemistry; D005433:Flour / Q000032:analysis*; D061353:Food Storage / Q000379:methods; D007700:Kinetics; D009943:Organophosphorus Compounds; D010573:Pesticide Residues / Q000032:analysis* / Q000378:metabolism; D010575:Pesticides / Q000032:analysis / Q000378:metabolism; D014908:Triticum / Q000737:chemistry* / Q000378:metabolism; D003313:Zea mays / Q000737:chemistry* / Q000378:metabolism
chemical_list: D009943:Organophosphorus Compounds; D010573:Pesticide Residues; D010575:Pesticides
keywords: Degradation; Gas chromatography-nitrogen phosphorus detection; Pesticides; Processed cereals; QuEChERS