A Novel Method (Fast and Simple) for Extraction of Pesticide Residues in Medical Plants

Pesticides, such as insecticides, herbicides, fungicides and acaricides, have been widely applied during the cultivation and the post-harvest storage of crops. Their use is intended to prevent the destruction of edible crops by controlling agricultural pests or unwanted plants and thereby improve food production .Although the use of pesticides in agricultural applications provides a wide range of beneficial effects, their inappropriate use can result in unacceptably high levels of compounds in the products that could reach the consumers directly or indirectly .The extensive use of pesticides has been a concern because of their potential harm to the environment and known or suspected toxic effects in humans, such as acute neurological toxicity, neuro developmental impairment, possible dysfunction of the immune, reproductive and endocrine systems, cancer, chronic kidney diseases and other potential diseases .Due to these concerns, the monitoring of pesticide residues in food products, especially in raw Plants(such as medical plants), must be pursued.Pesticides were extracted from each homogenized sample after thawing to room temperature, using a procedure entailing the following steps: 10 g of sample were weighed in a glass volumetric extraction vessel and 1.0 mL of toluene was added. The system apparatus was constructed and operated by a vacuum pump. Under the vacuum (100 mbar), 15 ml of 1,1,1,2-TFE were added to the extractor by using the scale of the extractor. After addition of 15 mL of 1,1,1,2-TFE to the extraction vessel from the solvent tank, the valves connecting the tank to the extraction vessel were closed. The vessel was vortexed thoroughly for 2 min, and the organic phase (1, 1,1,2-TFE and toluene) was drained into a beaker. After 1,1,1,2-TFE was evaporated, the remaining toluene phase was transferred to a vial and injectected to LC/MS.