Residue Analysis of Difenoconazole, Emamectin Benzoate and Fenazaquin on Tomatoes Using High Pressure Liquid Chromatography

Abstract

A supervised trial was conducted on tomato fruits to study the dissipation rates of three pesticides, difenoconazole (Score 25%EC), emamectin benzoate (Proclaim 5% SG) and fenazaquin (Pride 200, 20% SC) at Shanessa Village, Dhakahlia Governorate, Egypt. The tested pesticides were sprayed at recommended doses of 50 ml, 60 g and 300 ml in 100 liters water, for difenoconazole, emamectin benzoate and fenazaquin respectively on the tomato plants after three months of cultivation. The treated tomato fruits were randomly sampled in triplicates (100g per field replicate) after 1 hr, 1, 3, 6, 10, and 15 days period after pesticide application. Samples were extracted, cleaned up and then analyzed using HPLC method. The half-life values were calculated to be 3.16, 0.6 and 2.4 days for difenoconazole, emamectin benzoate and fenazaquin, respectively. The pre-harvest intervals (PHI) were determined to be 8, 3 and 1 days for tomatoes treated with difenoconazole, emamectin benzoate and fenazaquin under prevailed local field conditions, respectively.

Dissipation pattern and dietary risk assessment of some commonly used insecticides on tomato (Solanum lycopersicum L.)

“…When tomato fruits were fortified with 0.01 mg/kg, 89.20% of fenazaquin was recovered, with initial deposits of fenazaquin at a concentration of 300 mL/100 L being 0.520 mg/kg, which were not detectable after 15 days of application with half-life and pre-harvest intervals of 2.4 and 1 day, respectively (Nasr et al, 2009). The initial λ-cyhalothrin (20 g a.i./ha) residues on tomato crop were 0.718 mg/ kg, decreasing by 98.81% after 14 days with a half-life value of 3.12 days (Malhat et al, 2016).…”