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A multi-residue method using gas chromatography (GC) and gas chromatography!mass spectrometry (GC/MS) was developed for the determination of severalorganochlorine pesticides in three crude drugs: Astragali Radix (黃耆), ZizyphiSativae Fructus (大棗), and Zingiberis Rhizoma (乾薑). The pesticides including ｖ-BHC, β-BHC, γ-BHC, δ-BHC, 2,4'-DDE, 4,4'-DDE, 2,4'-DDT and 4,4'-DDT weredetermined using a modified extraction and refining procedure, separated by acapillary column DB-1, 0.25 μm, 0.25 mm * 30 M), observed with an electron capturedetector (ECD). amid confirmed by GC/MS if necessary. The precision and accuracy weresatisfactory. Calibration graphs of eight pesticides were constructed in the rangeof 0.25-2.0 - μg/ml and their correlation coefficients (r) were in the range of0.995-0.998. - Recovery studies were performed at the 1.0 ppm spike level of eachpesticide in these three crude drugs. Recovery rates were 66.4-98.0% for AstragaliRadix. 36.7-86.9% for Zizyphi Sativae Fructus, and 31.1-109.7% for Zingiberis Rhi