Determination of pesticide residues on tomatoes from greenhouses in Boudouaou and Douaouda, Algeria

Abstract

The aim of this study was to assess the use of pesticides (insecticides and fungicides) on tomatoes grown in greenhouses in two important agricultural regions near Algiers, Algeria (Boudouaou and Douaouda). Twenty samples were taken (ten from each region) to measure the residual concentration of nine pesticides (chlorpyrifos-ethyl, fenitrothion, metalaxyl, procymidon, triadimenol, diazinon, lambda-cyhalothrin, cyfluthrin, and indoxacarb). Samples were analysed by the multi-residue method, with solid-phase-extraction purification followed by quantification using gas chromatography-mass spectrometry. Five pesticides were detected in tomato samples from the Douaouda area, including chlorpyrifos-ethyl (0.028±0.001 mg/kg), fenitrothion (0.68±0.004 mg/kg), metalaxyl (0.048±0.015 mg/kg), procymidon (0.046±0.02 mg/kg) and triadimenol (0.035±0.003 mg/kg). In the Boudouaou area, only three pesticides were detected: chlorpyrifos-ethyl (0.43±0.011 mg/kg), triadimenol (0.21±0.002 mg/kg) and procymidon (0.03±0.0055 mg/kg). Synthetic pyrethroids were not found in either region. These results provide important information on pesticide contamination of tomatoes in two key agricultural areas in Algeria, and highlight the need to monitor and control residual pesticide levels to protect consumer health.