Degradation Pattern and Safety Evaluation of Azoxystrobin in Tomato Fruit

Tomato is one of the most important vegetables affected by various diseases. Owing to its effectiveness and safe in use, azoxystrobin is used in controlling major fungal diseases in tomato. An ethyl acetate method was validated for determining azoxystrobin in tomato using LC-MS/MS. The average recoveries ranged from 79.56% (±3.28) and 89.28% (±4.71) %. The dissipation and residue of azoxystrobin in tomato at good agricultural practice conditions were investigated. The dissipation results indicated that the half-life of azoxystrobin in tomato fitted in 1st+1st order was 1.818 and 2.32 at recommended dose double recommended dose respectively. The dissipation rates of azoxystrobin in tomato were almost the same at both doses. Terminal residues in tomato (0.004 mg kg-1) were all below the maximum residue limit (3 mg kg-1 by European Union). The results demonstrated the safety of using azoxystrobin at the recommended dosage to protect tomato from diseases. Moreover, the postharvest intervals estimated will be useful for farmers to ensure their field applications in a judicious manner and, in turn minimizing the residue loads within Maximum residue limit compliance, at harvest.