| The trace impurities of gutter oils were investigated by gas chromatography-mass spectrometry（GC-MS)with solid phase microextraction（SPME).By comparison of the trace endogenous substances of various pure vegetable oil and the exogenous impurities of the gutter oils from different areas,together with the analysis of the source of exogenous impurities,the characteristic components of the gutter oils from Guangzhou,Guizhou,Shenzhen and Beijing were acquired,which can be used as indicated components for the distinguishment of gutter oils.With high sensitivity and characteristic,this method was recruited in the blind samples evaluation organized by the Ministry of Public Health and the accuracy on positive samples was as high as 95.5%. |