Quantitative and morphological analysis of five heavy metal elements Cu, As, Cd, Hg, and Pb in hawthorn pill / 中草药

ABSTRACT

Objective: To study Cu, As, Cd, Hg, and Pb in 52 batches of of hawthorn pill samples from four different production enterprises in China. Methods: The residues of five heavy metal elements were determined with microwave digestion-inductively coupled plasma mass spectrometry (ICP-MS). The valence of As and Hg in the contaminated samples was analyzed with HPLC-ICP-MS. The heavy metal pollution in hawthorn pill was evaluated with the single and comprehensive pollution index method. Results: The method had good linear correlation (r ≥ 0.999 4).The detection limit ranges of five heavy metal elements were from 0.4 to 5.6 μg/kg. The recovery values ranged from 92.54% to 102.79%. The relative standard deviations for all elements were less than 3.5%. Green Standards of Foreign Trading Medicinal Plants & Preparations was used as the standard to evaluate the pollution status of Cu, As, Cd, Hg, and Pb in hawthorn pill. The results showed that the residues of Cu, Cd, and Pb were all bellow the limit of the standard, however, the As of some samples (S30, S37) from the production enterprise in Jilin exceeded the limit, Hg in all samples exceeded the limit. The As and Hg mainly existed in the form of arsenous acid (3), arsenic acid (5) and bivalent mercury. After the evaluation, there were 32 batches of safety level samples, two batches of warning level samples (S17, S25) from the production enterprise in Tianjin, which was occupied 7.41% of their samples, one batch of mild level polluted sample (S38), one batch of moderate level polluted sample (S40), and 16 batches of high level polluted samples (S28—S37, S39, S41—S45) from the production enterprise in Jilin, all samples from that enterprise were contaminated. Conclusion: The heavy metal pollution levels of hawthorn pill sold in china shows distinct difference since the different production enterprises, which should attach great importance to it. The study provides a reference for further research on safety of Chinese medicine.