title: Degradation of imazalil, orthophenylphenol and pyrimethanil in Clementine mandarins under conventional postharvest industrial conditions at 4°C.
abstract: The degradation of the postharvest fungicides imazalil, orthophenylphenol, and pyrimethanil was studied on Clementine mandarins during packinghouse storage for a 28day period at 4°C. Fruits to which orthophenylphenol was applied, were treated with imazalil and pyrimethanil at doses of 1000 and 2000mgL(-1), using cascade application for the later and cascade and wax for the former. The decay of the three fungicides was evaluated using an in-house validated analytical procedure that includes the extraction and dispersive clean up of the samples followed by the GC-MS determination of the pesticide residues. The impact of fruit storage time on pesticide residues concentration was assessed. The residues found for the different application technologies were always below the established Maximum Residue Limits by the Codex Alimentarius and the European Union (5mgkg(-1) for imazalil, 7 and 8mgkg(-1) for pyrimethanil, and 10mgkg(-1) and 5mgkg(-1) for orthophenylphenol). The fungicides dissipated differentially. Pyrimethanil showed little degradation, if any, at both tested concentrations, but the half-life of imazalil on the fruit was 15-18days, independent of the application technology. Orthophenylphenol dissipated with a half-life of 15days. The initial imazalil residue found after cascade treatment was not significantly different between the doses studied (p<0.5), whereas when the fungicide was included in wax as an emulsifiable concentrate the initial and final imazalil residues were significantly different. Final residue levels after 28days of storage were 0.12-0.24mgkg(-1) for imazalil, 0.68mgkg(-1) for 2-phenylphenol and 0.56mgkg(-1) for pyrimethanil for all the evaluated treatments.
authors.affiliation: Departamento de Química del Litoral, CENUR Litoral Norte, PAAP Universidad de la República (UdelaR), Uruguay; Cátedra de Farmacognosia y Productos Naturales, Departamento de Química Orgánica, Facultad de Química, Universidad de la República (UdelaR), Uruguay.
authors.forename: Natalia
authors.initials: N
authors.lastname: Besil
authors.affiliation: Cátedra de Farmacognosia y Productos Naturales, Departamento de Química Orgánica, Facultad de Química, Universidad de la República (UdelaR), Uruguay.
authors.forename: Andrés
authors.initials: A
authors.lastname: Pérez-Parada
authors.affiliation: Cátedra de Farmacognosia y Productos Naturales, Departamento de Química Orgánica, Facultad de Química, Universidad de la República (UdelaR), Uruguay.
authors.forename: Verónica
authors.initials: V
authors.lastname: Cesio
authors.affiliation: Programa Nacional de Investigación en Producción Citrícola, Instituto Nacional de Investigación Agropecuaria (INIA), Estación Experimental Salto Grande, Uruguay.
authors.forename: Pablo
authors.initials: P
authors.lastname: Varela
authors.affiliation: Programa Nacional de Investigación en Producción Citrícola, Instituto Nacional de Investigación Agropecuaria (INIA), Estación Experimental Salto Grande, Uruguay.
authors.forename: Fernando
authors.initials: F
authors.lastname: Rivas
authors.affiliation: Departamento de Química del Litoral, CENUR Litoral Norte, PAAP Universidad de la República (UdelaR), Uruguay; Cátedra de Farmacognosia y Productos Naturales, Departamento de Química Orgánica, Facultad de Química, Universidad de la República (UdelaR), Uruguay. Electronic address: heinzen@fq.edu.uy.
authors.forename: Horacio
authors.initials: H
authors.lastname: Heinzen
mesh_terms: D001713:Biphenyl Compounds / Q000737:chemistry*; D002957:Citrus / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry*; D011743:Pyrimidines / Q000737:chemistry*
chemical_list: D001713:Biphenyl Compounds; D007093:Imidazoles; D011743:Pyrimidines; C108337:pyrimethanil; C017435:enilconazole; C004369:2-phenylphenol
keywords: Citrus; Degradation; Imazalil (PubChem CID: 37175); Orthophenylphenol (PubChem CID: 7017); Postharvest fungicides; Pyrimethanil (PubChem CID: 91650)