Supercritical fluid extraction of pesticides in tomatoes
R. Salghi1*, A. Hormatallah2, M. Boulaid3, L. Bazzi4 , E. Ait Addi4
1Laboratoire d’Ingénierie de Génie des Procédés de l’Energie et de l’Environnement , Ecole Nationale des Sciences Appliquées d’Agadir B. P: 1136 Agadir - Morocco
2Département de protection des plantes, Institut Agronomique et Vétérinaire Hassan II, Complexe Horticole d'Agadir.
Laboratoire des Pesticides, B. P: 18/S Morocco.
3Pesticide Residue Research Group, Faculty of Experimental Sciences, University of Almeria 04071 Almeria, Spain
4Equipe de Chimie Physique Appliquée, Faculté des Sciences Agadir, Morocco
* Corresponding author. E-mail:email@example.com,firstname.lastname@example.org
Received: 12 January 2006; revised version accepted: 29 June 2006
Supercritical fluid extraction (SFE) method has been evaluated for the extraction of chlorothalonil, procymidone, endosulfan I, endosulfan II, endosulfan sulphate, and bifenthrine from tomato, using anhydrous magnesium sulphate as drying agent. The influence of different parameters, such as pressure, supercritical fluid volume and static modifier additions, on SFE recoveries from spiked tomato samples has been studied. Analysis were performed by gas chromatography (GC) with electron capture (ECD) detectors. The recovery of Chlorothalonil, Endosulfan I and Endosulfan sulfate were found to increase with increased pressure from 100 to 400 atm. The recoveries obtained in the experiments carried out on spiked SFE tomato samples were high for all concentrations studied, except for endosulfan sulphate for which the recoivery was estimated to 50 % at 10 µL and 77 % at 25 µL respectively. The recoveries obtained without modifier were less than those obtained using methanol as modifier, except for Endosulfan II and Endosulfan sulphate pesticides for which the recoveries obtained without modifier were slightly higher. The Chlorothalonil and Endosulfan I, gave poor recoveriers in absence of modifier (< 46%).
Keywords: Supercritical fluid extraction; Pesticides; Tomato.