Fate of three Insect Growth Regulators (IGR) Insecticides (Flufenoxuron, Lufenuron and Tebufenozide) in grapes following field application and through the wine making process

Dimitrios T Likas (1) , Nikolaos Tsiropoulos (2)

1 University of Thessaly, Dpt of Agriculture Crop production and rural environment
2 Dpt of Agriculture Crop production and rural environment

Abstract The dissipation of three insecticide flufenoxuron, lufenuron and tebufenozide residues in grapes after field treatments and during the winemaking process was evaluated. Residues were determined in grape, must, centrifuged must and wine samples by HPLC-UV after cyclohexane extraction and clean up on Silica phase cartridges. Vines in vineyards with white and red grapes located in Central Greece were sprayed once with each insecticide's commercial formulation at the recommended doses in experiments carried out in 2004 and repeated in 2006. The insecticide residues in grapes showed slow reduction for a period of 42 days after application following first-order kinetics with dissipation rates ranged from 0.011 to 0.018 mg kg-1 d-1. However, at the recommended pre-harvest interval (PHI) residues did not exceed 0.27±0.03 mg kg-1for flufenoxuron and lufenuron and 0.68±0.07 mg kg-1 for tebufenozide and they were clearly lower than the maximum residue limits (MRLs) set by EU in grape (2 mg Kg-1 for flufenoxuron, 1 mg kg-1 for lufenuron and 3 mg kg-1 for tebufenozide). Grape processing into wine caused an almost complete reduction for flufenoxuron and lufenuron as their residues in wine were below the method LOQs (<0.01 mg L-1), but only a moderate reduction for tebufenozide as concentrations from 0.13 to 0.26 mg L-1 were measured in the produced wines. Mean transfer factors for tebufenozide of 0.45 for white 'Roditis' and 0.34 for red 'Cabernet Sauvignon' were found from grapes into wine for the wines processed without maceration for tebufenozide. The wine-making technique (with or without maceration) had the same influence on tebufenozide residues in wine. Between various clarifying agents studied, charcoal was found the only one to be effective for removing tebufenozide residues from wine. Keywords: IGR insecticides, pesticides, residues, grapes, wine, vinification.

Mots clés: Life Sciences

Dimitrios T Likas, Nikolaos Tsiropoulos. Fate of three Insect Growth Regulators (IGR) Insecticides (Flufenoxuron, Lufenuron and Tebufenozide) in grapes following field application and through the wine making process. Food Additives and Contaminants, 2011, 28 (02), pp.189-197. ⟨10.1080/19440049.2010.542184⟩. ⟨hal-00668581⟩