Extrinsic harmful residues in Chinese herbal medicines: types, detection, and safety evaluation

Chinese herbal medicines (CHMs) are playing important roles in the treatment of diseases and human health care throughout the world. However, the extrinsic harmful residues have been threatening the therapies by destroying CHMs qualtiy which hinders the international trades of CHMs. This review summarized the extrinsic harmful residues contaminating CHMs in types, detection methods, national and international regulations, and made safety evaluations according to their contaminated levels, aiming to establish understanding among nations or organizations and provide references for the formulation or amendment of relative regulations.