Effect of storage temperature on the stability of chemical and physical properties with determination of malathion and fenitrothion insecticides formulations residues in cucumber fruits [electronic resource].

Includes references.

Two insecticides formulation recommended to be used for pest control in Egypt was subjected to storage conditions at the room temperature (25°C), 54°C and sunny place for 14 days and at 72°C for 3 days. The effect of storage on chemical stability and physical properties of malathion and sumithion (fenitrothion) insecticides were considered results showed that the chemical analysis by GC. fenitrothion insecticide was more stable when storage at different temperatures while malathion insecticide formulation was stable when storage at different temperatures than storage at 72°C and the dissipation % in active ingredient was 2.789% according to FAO/WHO meeting (2002) The used formulations become non conformity when storage at 72 °C . GC/MS analysis gives the same separation peaks after and before at all storage conditions except at sunny place its give a new separation peaks after storage. An IR analysis showed that % match of malathion and sumithion insecticides formulations was more than 90 at different storage temperature. On the other hand results showed that physical properties (Emulsification test) were not affected by storage temperature except in case of storage at 72°C whereas, a cream layers 5ml was found at the tap of the containers. So, the best stability for physic-chemical properties could be achieved if the malathion and sumithion formulations stored at room temperature. 54 °C and in sunny place while storage at 72°C were more effective on malathion and sumithion formulations. Cucumber plants were treated with the recommended rate of malathion and sumithion under the normal field conditions in winter season. Residues analysis showed that the initial deposits (0.5 and0.2ppm) in cucumber fruits. The percentage of loss was (21.9 & 44.10 %) one day after treatment. The residual half life in cucumber was 54.79 and 26.83 hours. For malathion and sumethion respectively. Washing process was effective methods for value 0.42 &0.13 ppm of initial deposits residual of malathion and sumithion respectively on cucumber fruits. The pesticide residues was dissipated to different degrees, with the time elapsed after spraying. The Pre Harvest Interval (PHI) were 14 days post treatment for malathion and sumithion on cucumber fruits, and the residue was low than Acceptable Daily Intake (ADI) after PHI period. These values for malathion and fenitrothion. by CAC/pr 2000 was 0.02 and 0.005 mg/kg (ppm) respectively.

Summary in Arabic.

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