GC-MS DETERMINATION OF ORGANOCHLORINE PESTICIDES IN 5 MEDICINAL-PLANTS

Capilllary gas chromatography-mass spectrometry (GC-MS) in the electro n impact (EI) mode and using selected ion monitoring (SIM) has been us ed to determine the main organochlorine pesticides in five commonly us ed medicinal plants (mint, vervain, camomile, lime tree and tea). Soli d-phase extraction (SPE) is proposed for the treatment of these medici nal herbs. Validation of this step using factorial discriminant analys is (FDA) has shown that these plants can not be considered as one homo geneous group with regard to the extraction procedure. Consequently, t wo procedures have been designed. In each procedure, the plant is infu sed prior to SPE. Elution is achieved with n-hexane-dichloromethane (8 5:15, v/v). If necessary, the organic extract is treated with trifluor oacetic acid (TFA) to reduce matrix interferences.