Trace heavy metals and harmful elements in roots and rhizomes of herbs: Screening level analysis and health risk assessment

OBJECTIVE: Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines (CHMs), and roots and rhizomes parts showed a higher content than other parts. To investigate the residue level and assess the potential human health risk of heavy metals and harmful elements in roots and rhizomes, 720 batches of the sample representing 20 species of herbs from different sources were collected. METHODS: The content of Pb, Cd, As, Hg, and Cu in the digests was determined using ICP-MS. The chronic hazard index estimate based on non-cancer hazard quotient (HQ) was applied for potential health risk assessment of Pb, Cd, As, Hg, and Cu via consumption of CHMs. RESULTS: Compared with the Chinese limit standard (Chinese Pharmacopoeia Commission, 2020 edition) of Pb, Cd, As, Hg, and Cu in Ginseng Radix et Rhizoma, the exceedance percentage of Pb in total samples was 14.1%, which were generally far higher than Cd, As, Hg, and Cu. Health risk assessment results based on hazard quotient calculating showed that total HQ of Cu, Pb, As, Cd, and Hg in Pulsatillae Radix and Clematidis Radix et Rhizoma exceeded 1, with the value of 1.543 and 1.235. Besides, Arsenic had the highest HQ value (0.957) in Pulsatillae Radix. CONCLUSION: Consuming raw materials of Pulsatillae Radix and Clematidis Radix et Rhizoma may pose a potential risk and Arsenic residues in Pulsatillae Radix deserved special attention.