Technical guidelines for risk assessment of heavy metals in traditional Chinese medicines.

BACKGROUND: Heavy metals are considered a global concern because they can deteriorate human health. This guideline aims to scientifically evaluate health risk of heavy metals in TCM and to propose a reference for decision making in developing TCM-related health policies. METHODS: Using a multidisciplinary approach, a steering committee oversaw the development of the guideline. To obtain a reasonable and accurate risk assessment, key exposure assessment parameters for TCM, e.g., exposure frequency (EF), exposure duration (ED), and daily ingestion rate (IR) were obtained from surveys. In addition, transfer rates for heavy metals from Chinese medicinal materials (CMM) to decoctions or preparations were examined. RESULTS: Based on the scientific theory of risk control, the guideline was designed systematically, and principles and procedures for the risk assessment of heavy metals in TCM were identified. The guideline can be utilized to assess the risk of heavy metals in CMM and Chinese patent medicines (CPM). CONCLUSION: This guideline may help standardize the risk assessment of heavy metals in TCM, advance regulatory standards for heavy metals in TCM, and ultimately improve human health through scientific TCM usage in clinic.

Novel Integrated Tiered Cumulative Risk Assessment of Heavy Metals in Food Homologous Traditional Chinese Medicine Based on a Real-Life-Exposure Scenario.

In order to serve population health better, the first integrated tiered decision tree for cumulative risk assessment of co-exposure of Pb-, Cd-, and As-associated health risks in food homologous traditional Chinese medicine (TCM) was designed, after measuring their concentrations by inductively coupled plasma-mass spectroscopy (ICP-MS). Basically, our three-step decision tree involving hazard quotient (HQ), hazard index (HI), and target-organ toxicity dose (TTD) modification of the HI method was developed to evaluate the potential risks of 949 batches of 15 types of food homologous TCM. To acquire a real-life exposure scenario, the cumulative risk assessment model was established by optimizing key parameters, such as ingestion rates, frequency, and duration of exposure to food homologous TCM based on questionnaire data. As a result, the mean concentrations of Pb, Cd, and As in 949 batches of food homologous TCM were 0.896, 0.133, and 0.192 mg/kg, respectively. The HQ values of As for Angelica sinensis (Oliv.) Diels and Houttuynia cordata Thunb. were 1.04 and 1.01, respectively, for females. Other HQs of Pb, Cd, or As in food homologous TCM were lower than 1 for both males and females. However, after rapid screening of the co-exposure health risks of heavy metals by the HI method, cumulative risk assessment results acquired by TTD modification of the HI method implied that the potential health risks associated with the co-exposure of Pb, Cd, and As in Lonicera japonica Thunb. and Houttuynia cordata Thunb. ingested as both TCM and food were of concern in the clinic. Additionally, the cumulative risks of Pb, Cd, and As in Mentha canadensis L., Chrysanthemum indicum L., and Zaocys dhumnades (Cantor) only used as food exceeded the human tolerance dose. Collectively, our innovation on the tiered strategy of decision tree based on a real-life exposure scenario provides a novel approach engaging in the cumulative risk assessment of heavy metals in food homologous TCM. All in all, such effort attempts to scientifically guide the rational use of TCM in the treatment of the complex diseases and the improvement of population health.

[Determination and risk assessment of heavy metals and harmful elements residues in Niuhuang Qingwei Pills based on ICP-MS].

To achieve a comprehensive understanding of heavy metals and harmful elements residues in Niuhuang Qingwei Pills,49 samples from 18 manufactures were collected from 31 provinces in China.Risk assessment and control preparations were applied innovatively in evaluation of exogenous pollution in traditional Chinese Medicine.Determination methods for Pb,Cd,As,Hg and Cu were established by inductively coupled plasma mass spectrometry(ICP-MS).Based on the procedures including hazard identification,hazard characterization,exposure assessment and risk characterization,risk assessment was performed and residual limits for Pb,Cd,As,Hg and Cu in the drug were formulated.The results showed that the hazardous quotients(HQ) of the elements were decreased in the following order:Pb>As>Cu>Hg>Cd,and the total hazardous index(HI) of heavy metals and harmful elements in Niuhuang Qingwei Pills was above 1,implying health risk of the drug.Under the proposed limits,5 elements in the control preparation as well as Cd and Cu in the samples were within the limits range,but the excess rates of Pb,As and Hg in the samples were 12%,12% and 14%,respectively.For the first time,basic steps for risk assessment of Chinese patent medicine were established,which provided model and reference for risk assessment and limit formulation of other drugs.