PESTICIDE RESIDUES IN TOMATOES GROWN IN GREENHOUSES IN SOUSS MASSA VALLEY IN MOROCCO AND DISSIPATION OF ENDOSULFAN AND DELTAMETHRIN

摘要

Pesticide residue analyses of 20 tomato samples picked up from 10 packinghouses in the area of Souss Valley in the southern part of Morocco showed that 8 samples had residues of 1.01-1.20 mg/kg of endosulfan and 4 samples 0.22-1.00 mg/kg of deltamethrin, which exceeded the European maximum residue limits (MRLs) for tomato fruits. Degradation kinetics of endosulfan were governed by the first order kinetic model with a good correlation and a time of half-life equal to 12.9 days. The study on the dissipation of deltamethrin from tomatoes showed a rapid decrease during the first two weeks, followed by a period of slower residue reduction, and, 16 days after application, the level was below the European tolerance.