Abstract: Objective To investigate the distribution patterns and concentration levels of 16 rare earth elements (REEs) in 22 species of medicinal and edible homologous Chinese herbal medicines from the Guangxi. Methods The concentrations of REEs were determined utilizing microwave digestion followed by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). The distribution patterns of these elements were subsequently explored through a combination of correlation analysis,cluster analysis, and principal component analysis (PCA). Results The results indicated that among the 487 samples across 22 species, the mean total REE concentrations in Ganoderma lucidum (2.570 mg/kg), Sophorae Flos (2.569 mg/kg), and Houttuynia cordata (2.265 mg/kg) were significantly elevated compared to other species (all P<0.05). Statistically significant variations in REE content were observed among samples from different geographical origins (P<0.05). Furthermore, principal component analysis revealed that light rare earth elements (LREEs),notably Lanthanum (La) and Cerium (Ce), were the principal contributors to the total variance (explaining 65.13%). Conclusion It was concluded that rare earth elements are ubiquitously present in the medicinal and edible homologous herbal materials from Guangxi. Both the species and the geographical provenance were found to be significant determinants of REE content. This underscores the necessity of establishing a differentiated regulatory framework, including specific maximum permissible limits, based on both species and origin.

Key words: Medicinal and edible homologous materials, Rare earth elements, ICP-MS/MS, Health risk, Guangxi