title: Residue analysis of fipronil and difenoconazole in okra by liquid chromatography tandem mass spectrometry and their food safety evaluation.
abstract: A liquid chromatography tandem mass spectrometry (LC-MS/MS) based method is reported for simultaneous analysis of fipronil (plus its metabolites) and difenoconazole residues in okra. The sample preparation method involving extraction with ethyl acetate provided 80-107% recoveries for both the pesticides with precision RSD within 4-17% estimated at the limits of quantification (LOQ, fipronil=1ngg(-1), difenoconazole=5ngg(-1)) and higher fortification levels. In field, both the pesticides dissipated with half-life of 2.5days. The estimated pre-harvest intervals (PHI) for fipronil and difenoconazole were 15 and 19.5days, and 4 and 6.5days at single and double dose of field applications, respectively. Decontamination of incurred residues by washing and different cooking treatments was quite efficient in minimizing the residue load of both the chemicals. Okra samples harvested after the estimated PHIs were found safe for human consumption.
authors.affiliation: National Referral Laboratory, ICAR-National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India; Department of Agrochemicals and Pest Management, Shivaji University, Kolhapur 416 004, India.
authors.forename: Sandip
authors.initials: S
authors.lastname: Hingmire
authors.affiliation: National Referral Laboratory, ICAR-National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India.
authors.forename: Dasharath P
authors.initials: DP
authors.lastname: Oulkar
authors.affiliation: National Referral Laboratory, ICAR-National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India.
authors.forename: Sagar C
authors.initials: SC
authors.lastname: Utture
authors.affiliation: National Referral Laboratory, ICAR-National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India.
authors.forename: T P
authors.initials: TP
authors.lastname: Ahammed Shabeer
authors.affiliation: National Referral Laboratory, ICAR-National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India. Electronic address: kbgrape@yahoo.com.
authors.forename: Kaushik
authors.initials: K
authors.lastname: Banerjee
mesh_terms: D028483:Abelmoschus / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000379:methods*; D004148:Dioxolanes / Q000737:chemistry*; D005506:Food Contamination / Q000032:analysis; D059022:Food Safety / Q000379:methods*; D010573:Pesticide Residues / Q000032:analysis*; D011720:Pyrazoles / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014230:Triazoles / Q000737:chemistry*
chemical_list: D004148:Dioxolanes; D010573:Pesticide Residues; D011720:Pyrazoles; D014230:Triazoles; C115058:difenoconazole; C082360:fipronil
keywords: Decontamination; Difenoconazole residues in okra; Dissipation kinetics; Fipronil residues in okra; LC–MS/MS; Pre-harvest interval