ABSTRACT
This project was launched to study on the overall residual status of heavy metals of comprehensive understanding in decoction pieces of Bupleuri Radix (DPBR) from different habitats and risk assessment. In this study, inductively coupled plasma mass spectrometry was used to determine the heavy metals of 30 batches of Bupleuri Radix in different producing areas. Simulated gastrointestinal fluid method was used to determine the dissolution rate of heavy metals in the simulated gastrointestinal fluid and the average daily intake Average Daily Dose (ADD) and Hazard Quotient (HQ) index were used to assess the risk of heavy metals in DPBR. The results showed that the contents of copper (Cu), lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg) in the 30 batches of DPBR didn't exceed the limit of Chinese Pharmacopeia, however, the chromium (Cr) in DPBR exeeded the limit set by NSF in USA and the limit for herbal ingredients in Canada. The mean bioaccessible heavy metal concentrations decreased from Cu (5.27 mg·kg⁻¹)>Cr (4.67 mg·kg⁻¹)>As (0.18 mg·kg⁻¹)>Pb (0.12 mg·kg⁻¹)>Cd (0.06 mg·kg⁻¹), and Hg was not detected in this test. In addition, cumulative non-carcinogenic health risks (HI) for adults and children were 0.799 and 0.714, respectively. Both HI values in adults and children for combined trace element and heavy metal element exposures were below the value of 1 (HI<1), indicating very low carcinogenic health risk. Heavy metals toxicity in herbal medicines and its health risk to humans would be overestimated when assessed only by the total concentrations without considering the bioaccessibility. Therefore, bioaccessibility has great significance for evaluating the human health risks induced by heavy metals.