title: Validation of a GC-MS method for the estimation of dithiocarbamate fungicide residues and safety evaluation of mancozeb in fruits and vegetables.
abstract: A sensitive and rugged residue analysis method was validated for the estimation of dithiocarbamate fungicides in a variety of fruit and vegetable matrices. The sample preparation method involved reaction of dithiocarbamates with Tin(II) chloride in aqueous HCl. The CS2 produced was absorbed into an isooctane layer and estimated by GC-MS selected ion monitoring. Limit of quantification (LOQ) was ⩽40μgkg(-1) for grape, green chilli, tomato, potato, brinjal, pineapple and chayote and the recoveries were within 75-104% (RSD<15% at LOQ). The method could be satisfactorily applied for analysis of real world samples. Dissipation of mancozeb, the most-used dithiocarbamate fungicide, in field followed first+first order kinetics with pre-harvest intervals of 2 and 4days in brinjal, 7 and 10days in grapes and 0day in chilli at single and double dose of agricultural applications. Cooking practices were effective for removal of mancozeb residues from vegetables.
authors.affiliation: National Referral Laboratory, National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India.
authors.forename: Sumaiyya
authors.initials: S
authors.lastname: Mujawar
authors.affiliation: National Referral Laboratory, 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: Centro de Investigación en Contaminación Ambiental (CICA), Universidad de Costa Rica, P.O. 2060 San José, Costa Rica.
authors.forename: Eddie
authors.initials: E
authors.lastname: Fonseca
authors.affiliation: Centro de Investigación en Contaminación Ambiental (CICA), Universidad de Costa Rica, P.O. 2060 San José, Costa Rica.
authors.forename: Jessie
authors.initials: J
authors.lastname: Matarrita
authors.affiliation: National Referral Laboratory, 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: D003296:Cooking; D005506:Food Contamination / Q000032:analysis*; D059022:Food Safety; D005638:Fruit / Q000737:chemistry* / Q000254:growth & development; D005659:Fungicides, Industrial / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D008344:Maneb / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D013997:Time Factors; D014675:Vegetables / Q000737:chemistry*; D015038:Zineb / Q000032:analysis*
chemical_list: D005659:Fungicides, Industrial; D010573:Pesticide Residues; D008344:Maneb; C013099:mancozeb; D015038:Zineb
keywords: Dithiocarbamate fungicides; GC–MS; Mancozeb; Method validation; Pre-harvest interval; Selected ion monitoring