Monitoring of extrinsic harmful residues in herbal paste / 中草药

ABSTRACT

Objective: To monitor the pesticide residues and heavy metal residues in the herbal paste and to provide the basis for the total quality control of the herbal paste. Methods: The contents of benzene hexachloride (BHC, containing α-BHC, β-BHC, γ-BHC, and δ-BHC), dichloro-diphenyl-trichloroethane (DDT, containing PP'-DDE, PP'-DDD, OP'-DDT, and PP'-DDT), and pentachloroni- trobenzene (PCNB) were determined by using the method of gas chromatography. The contents of Pb, Cd, As, Hg, and Cu were determined by using atomic absorption spectrometry. Results: Pesticide residues in four batches of the herbal paste were as follows The total BHC and DDT were less than 20 ng/g, and PCNB was less than 10 ng/g. The heavy metal residues were as follows Pb was less than 0.5 μg/g, Cd was less than 30 ng/g, As and Hg were less than 0.2 μg/g, and Cu was less than 2 μg/g. Conclusion: Pesticide residues and heavy metal residues in the herbal paste accord with the limit standards of Chinese Pharmacopoeia and the EU rules.