| A currently, sensitively, rapidly quanlitive and quantitive method that can be used to determine multiresidues in most of medicine crops was established by studies on the GC condition, NCIMS condition ( including ions detected, ions measured, ionsets) calibration, LODs, LOQs extractive condition and recoveries of 38 pesticides and . Methods of 38 pesticide residues in 48 traditional Chinese medicines were developed.Using heptachlor epoxide as interal standard, the linearity of 38 pesticides were good with r between 0.99～1.000,except phosphamdon with rat 0.981.The RSD for most pesticides were below 10%.Traditional Chinese medicines were classified two kinds according to the main component and different methods were used to extract the pesticide residues : Acetone-water was used for syrum medicines; organoic solvent was used for dry partition and oil-contained medicines. After clean-up with Florisil coloum, the extract was ready for GCNCIMS/SIM analysis. The recoveries of most pesticides in 14 different medicine crops were between 70%～120% with RSD<15%.The LODs were in 0.1～ 10ppb except dichlorvos , chlordimeform, phosphamidon, triazophos(ppm level),The recoveries and LODs of most pesticides were in the range of method validation.The pesticide residuces go beyond the tolerance according to PRC pharmacopoeia(2005) in 434 batches of 48 traditional Chinese medicines plants detected by this method shows : there were 350 batches were detected pesticide residues more or less cover the total batches about 81% and pesticide residuces contented over 100ng/g were 32 batches,cover about 9%.
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