Seven cases of fatal aconite poisoning: forensic experience in China

Toxicological investigation of 25 aconitine-induced deaths from 2005 to 2023

Aconitum herbs contain several highly toxic diester-diterpenoid alkaloids, including aconitine, mesaconitine, and hypaconitine. However, finding the cause of death is rather difficult for forensic pathologists during forensic autopsy of aconitine-induced death. Therefore, the ability to determine Aconitum alkaloids is important in these cases. The aim of this study was to review the data for alkaloids in postmortem specimens from 25 aconitine-induced deaths received by the Academy of Forensic Science from 2005 to 2023. Aconitum alkaloids were analyzed using an LC-MS/MS method, which was validated for blood, urine, and liver tissue. Briefly, 0.5 mL (g) of biological sample was subjected to liquid-liquid extraction with diethyl ether at pH 9.2. In 25 aconitine-induced deaths, the blood levels of aconitine, mesaconitine, and hypaconitine were 2.9-470 ng/mL (n = 22), ＜LOQ-30 ng/mL (n = 10), and ＜LOQ-5.0 ng/mL (n = 10), respectively. In some cases, other biological samples (e.g., urine, gastric contents, and liver tissue) and the materials seized on site (e.g., homemade medicinal liquor) were also analyzed. A significant positive correlation was observed between the biological samples and the seized materials for the concentration ratios of aconitine to mesaconitine and of aconitine to hypaconitine. The risk of aconite poisoning is increased by inappropriate administration, including drinking of homemade medicinal liquors containing Aconitum alkaloids, the use of unprocessed or improperly processed Aconitum plant material, and excessive consumption or misuse without doctors' directions. Accidental death caused by misuse of herbal drugs was the main cause of death in the 25 aconitine-induced deaths studied here.

Detoxification and underlying mechanisms towards toxic alkaloids by Traditional Chinese Medicine processing: A comprehensive review

BACKGROUND

Alkaloids have attracted enduring interest worldwide due to their remarkable therapeutic effects, including analgesic, anti-inflammatory, and anti-tumor properties, thus offering a rich source for lead compound design and new drug discovery. However, some of these alkaloids possess intrinsic toxicity. Processing (Paozhi) is a pre-treatment step before the application of herbal medicines in traditional Chinese medicine (TCM) clinics, which has been employed for centuries to mitigate the toxicity of alkaloid-rich TCMs.

PURPOSE

To explore the toxicity phenotypes, chemical basis, mode of action, detoxification processing methods, and underlying mechanisms, we can gain crucial insights into the safe and rational use of these toxic alkaloid-rich herbs. Such insights have the great potential to offer new strategies for drug discovery and development, ultimately improving the quality of life for millions of people.

METHODS

Literatures published or early accessed until December 31, 2023, were retrieved from databases including PubMed, Web of Science, and CNKI. The following keywords, such as "toxicity", "alkaloid", "detoxification", "processing", "traditional Chinese medicine", "medicinal plant", and "plant", were used in combination or separately for screening.

RESULTS

Toxicity of alkaloids in TCM includes hepatotoxicity, nephrotoxicity, neurotoxicity, cardiotoxicity, and other forms of toxicity, primarily induced by pyrrolizidines, quinolizidines, isoquinolines, indoles, pyridines, terpenoids, and amines. Factors such as whether the toxic-alkaloid enriched part is limited or heat-sensitive, and whether toxic alkaloids are also therapeutic components, are critical for choosing appropriate detoxification processing methods. Mechanisms of alkaloid detoxification includes physical removal, chemical decomposition or transformation, as well as biological modifications.

CONCLUSION

Through this exploration, we review toxic alkaloids and the mechanisms underlying their toxicity, discuss methods to reduce toxicity, and unravel the intricate mechanisms behind detoxification. These offers insights into the quality control of herbs containing toxic alkaloids, safe and rational use of alkaloid-rich TCMs in clinics, new strategies for drug discovery and development, and ultimately helping improve the quality of life for millions of people.

Data Science and Plant Metabolomics

The study of plant metabolism is one of the most complex tasks, mainly due to the huge amount and structural diversity of metabolites, as well as the fact that they react to changes in the environment and ultimately influence each other. Metabolic profiling is most often carried out using tools that include mass spectrometry (MS), which is one of the most powerful analytical methods. All this means that even when analyzing a single sample, we can obtain thousands of data. Data science has the potential to revolutionize our understanding of plant metabolism. This review demonstrates that machine learning, network analysis, and statistical modeling are some techniques being used to analyze large quantities of complex data that provide insights into plant development, growth, and how they interact with their environment. These findings could be key to improving crop yields, developing new forms of plant biotechnology, and understanding the relationship between plants and microbes. It is also necessary to consider the constraints that come with data science such as quality and availability of data, model complexity, and the need for deep knowledge of the subject in order to achieve reliable outcomes.

Advancements and future prospective of DNA barcodes in the herbal drug industry

Ethnopharmacological relevance: The past couple of decades have witnessed the global resurgence of medicinal plants in the field of herbal-based health care. Increased consumption of medicinal plants and their derivative products is the major cause of the adulteration issues in herbal industries. As a result, the quality of herbal products is affected by spurious and unauthorized raw materials. Recent development in molecular plant identification using DNA barcodes has become a robust methodology to identify and authenticate the adulterants in herbal samples. Hence, rapid and accurate identification of medicinal plants is the key to success for the herbal industry. Aim of the study: This paper provides a comprehensive review of the application of DNA barcoding and advanced technologies that have emerged over the past 10 years related to medicinal plant identification and authentication and the future prospects of this technology. Materials and methods: Information on DNA barcodes was compiled from scientific databases (Google Scholar, Web of Science, SciFinder and PubMed). Additional information was obtained from books, Ph.D. thesis and MSc. Dissertations. Results: Working out an appropriate DNA barcode for plants is challenging; the single locus-based DNA barcodes (rbcL, ITS, ITS2, matK, rpoB, rpoC, trnH-psbA) to multi-locus DNA barcodes have become the successful species-level identification among herbal plants. Additionally, multi-loci have become efficient in the authentication of herbal products. Emerging advances in DNA barcoding and related technologies such as next-generation sequencing, high-resolution melting curve analysis, meta barcodes and mini barcodes have paved the way for successful herbal plant/samples identification. Conclusion: DNA barcoding needs to be employed together with other techniques to check and rationally and effectively quality control the herbal drugs. It is suggested that DNA barcoding techniques combined with metabolomics, transcriptomics, and proteomics could authenticate the herbal products. The invention of simple, cost-effective and improved DNA barcoding techniques to identify herbal drugs and their associated products of medicinal value in a fool-proof manner will be the future thrust of Pharmacopoeial monograph development for herbal drugs.

Aconitine induces cardiotoxicity through regulation of calcium signaling pathway in zebrafish embryos and in H9c2 cells

Fuzi, the processed lateral roots of Aconitum carmichaelii Debx., is a traditional herbal medicine that is well known for its excellent pharmacological effects and acute toxicity. Aconitine is one of the diester-diterpene alkaloids and well-known for its arrhythmogenic effects. However, the effects of aconitine in zebrafish have rarely been studied. Therefore, we investigated the effects of aconitine on zebrafish embryos and H9c2 cells. Zebrafish embryos at 48 hours postfertilization were exposed to aconitine, and then, cardiac function and apoptosis were measured. Through transcriptomic analysis, the cardiotoxicity of aconitine in zebrafish embryos was involved in regulating Ca²⁺ signal pathways. A reverse transcription-polymerase chain reaction was performed to verify the expression of Ca²⁺ pathway-related genes after 12, 24, 36 and 48 hours of treatment. Meanwhile, intracellular Ca²⁺ concentrations and cell apoptosis were observed in H9c2 cells treated with half-maximal inhibitory concentration values of aconitine for 30 minutes. The protein levels of troponin T (TnT), caspase 3, Bcl-2 and Bax were detected by western blot analysis. In vivo, 2.0 and 8.0 μm aconitine decreased the heart rate and inhibited the contraction of ventricles and atria in a dose- and time-dependent manner. Furthermore, aconitine increased expression of cacna1c, RYR2, atp2a2b, Myh6, troponin C, p38, caspase 3, Bcl-2 and Bax for 12 hours. In vitro, 1.5 and 4.5 mm aconitine caused intracellular Ca²⁺ ion oscillation, increased rates of apoptosis, inhibited TnT and Bcl-2 protein expression, and promoted caspase 3 and Bax protein expression. These data confirmed that aconitine at various concentrations induced cardiac dysfunction and apoptosis were related to the Ca²⁺ signaling pathway.

Quantitative determination of talatisamine and its pharmacokinetics and bioavailability in mouse plasma by UPLC-MS/MS

Talatisamine, as the efficacy ingredient of Aconitum, was known as a novel specific blocker for the delayed rectifier K⁺ channels in rat hippocampal neurons. In this study, a rapid, selective and reproducible UPLC-MS/MS separation method was established and fully validated for the quantitative determination of talatisamine levels in ICR (Institute of Cancer Research) mouse blood. A total of 24 healthy male ICR mice were divided into four groups that was administered talatisamine via intravenous at a dose of 1 mg/kg and oral administration of three doses (2, 4, 8 mg/kg). All blood samples were protein precipitate by using acetonitrile with an internal standard (IS) deltaline. The effective chromatographic separation was carried out through an UPLC BEH C18 analytical column (2.1 mm × 50 mm, 1.7 μm) with an initial mobile phase that consisted of acetonitrile and 10 mmol/L ammonium acetate aqueous solution (containing 0.1% formic acid) with a gradient elution pumped at a flow rate of 0.4 mL/min. Also, an electrospray ionization (ESI) was applied to quantify the talatisamine in the positive ions mode. The method validation demonstrated good linearity over the range of 1-1000 ng/mL (r² ≥ 0.9993) for talatisamine in mouse blood with a lower limit of quantification (LLOQ) at 1 ng/mL. The accuracy values of the method were within 89.4% to 113.3%, and the matrix effects were between 103.2% and 106.3%. The mean extraction recoveries for talatisamine obtained from four concentrations of QC blood samples were exceeded 71.7%, and the relative standard deviation (RSD) both of intra- and inter-day precision values for replicate quality control samples did not exceed 15% respectively for all analytes during the assay validation. This method was successfully applied to the evaluation of the pharmacokinetic of talatisamine, regardless of intragastric or intravenous administration in mice. Based on the pharmacokinetics data, the bioavailability of talatisamine in mice was >65.0% after oral administration, exhibiting an excellent oral absorption.

Rapid identification of Aconitum plants based on loop-mediated isothermal amplification assay

Objective

Aconitum plants (Ranunculaceae) exhibit toxicity, and accidental ingestion of the plants has been reported in Japan. Identifying the cause of poisoning is important for emergency medical treatment, and a rapid and simple detection technique is required for the identification of poisoning cause. In the present study, we developed a rapid and simple method for detecting Aconitum plant DNA using a loop-mediated isothermal amplification (LAMP) assay.

Results

Specific LAMP primers for Aconitum plants were designed based on the trnL–trnF intergenic spacer region. Using the LAMP primers, the LAMP assay included an initiation reaction of 10 min followed by amplification for 20 min at the isothermal reaction temperature of 65 °C. The LAMP reaction was demonstrated to be specific and highly sensitive to Aconitum plants, given that the assay can be used for 1 pg of purified DNA. Using raw extracted DNA as template, the entire detection procedure from DNA extraction to final detection required only 30 min. Moreover, the protocol identified samples containing approximately 5 mg of Aconitum plants cooked and digested with artificial gastric juice. The currently proposed protocol exhibits good potential as a screening method of Aconitum plant poisoning for emergency medical care.

Electronic supplementary material

The online version of this article (10.1186/s13104-019-4463-1) contains supplementary material, which is available to authorized users.

Metabolomics of Clinical Poisoning by Aconitum Alkaloids Using Derivatization LC-MS

The root of Aconitum kusnezoffii (Caowu in Chinese, CW) is not only commonly used as a traditional Chinese medicine (TCM), but also served as a tonic in China. Due to its high toxicity, clinical poisoning cases induced by CW have frequently been reported. However, the mechanism is still unclear. In this study, Aconitum alkaloids and altered endogenous metabolites in CW poisoning patients were investigated to elucidate the possible intoxication mechanism. Eighteen alkaloids, including 6 toxic diester diterpenoid alkaloids (DDAs), were determined from the sera of patients. At the same time, 5-(diisopropylamino)amylamine (DIAAA) derivatization-ultrahigh performance liquid chromatography- quadrupole-time of flight mass spectrometry (UHPLC-Q-TOF/MS) approach was applied in the metabolomics analysis to find much more carboxyl-containing metabolites (CCMs), which are the essential components for life and critical to elucidate the mechanism of toxicity. As a result, 32 altered metabolites after poisoning were identified. Among them, hydroxyeicosatetraenoic acids (HETEs) and some dicarboxylic acids were first found to be related to Aconitum alkaloids toxicity. Finally, biological pathway analysis indicated that the significantly changed metabolites were primarily involved in amino acid metabolism, TCA cycle, fatty acid metabolism, pyruvate metabolism, arachidonic acid metabolism, sphingolipid metabolism and so on. These results can not only provide more information on the mechanism of CW intoxication but also help the clinical diagnosis of CW poisoning.

Cardiotoxicity evaluation and comparison of diterpene alkaloids on zebrafish

Diterpene alkaloids (DAs) have a broad spectrum of pharmacological activities, but exhibiting extremely serious cardiotoxicity to induce arrhythmia, heart arrest, even death. This study aimed to evaluate the cardiotoxicity of three diester diterpene alkaloids (DDAs) including aconitine (AC), mesaconitine (MAC), hypaconitine (HAC) and three monoester diterpene alkaloids (MDAs) including 14-α-benzoylaconine (BAC), 14-α-benzoylmesaconine (BMAC), 14-α-benzoylhypaconine (BHAC) on zebrafish. Firstly, the zebrafish embryos after a 72-hour post fertilization were treated with different doses of AC, MAC, HAC, and BAC, BMAC and BHAC for 2, 10 and 24 h, respectively. The heart rates of the treated embryos were calculated and the morphological images of body, together with heart fluorescence were obtained. Results demonstrated that AC, MAC, and HAC at low doses (15.6 and 31.3 μM) decreased the heart rates and increased them at high doses (62.5, 125, and 250 μM), while BAC, BMAC, and BHAC decreased the heart rates in the dose range of 31.3-250 μM, but the highest dose (500 μM) of BAC and BMAC increased the heart rates. In addition, AC, MAC, and HAC exhibited serious organic and functional toxicities, while BAC, BMAC, and BHAC did not. It could be induced that DDAs expressed stronger cardiotoxicities than MDAs, which might be due to that they were known as the Na⁺ channel activators and K⁺ channel inhibitors, respectively. The β-acetate at C-8 position, along with the protonated nitrogen on ring A of their chemical structures contributed more for their different cardiotoxicities. This is the first study on cardiotoxicity comparison of DAs, providing references for the rational and safe application of these compounds and some plant species containing them to reduce side effects while retaining therapeutic efficacy.

Using SSR-HRM to Identify Closely Related Species in Herbal Medicine Products: A Case Study on Licorice

Traditional herbal medicines have played important roles in the ways of life of people around the world since ancient times. Despite the advanced medical technology of the modern world, herbal medicines are still used as popular alternatives to synthetic drugs. Due to the increasing demand for herbal medicines, plant species identification has become an important tool to prevent substitution and adulteration. Here we propose a method for biological assessment of the quality of prescribed species in the Chinese Pharmacopoeia by use of high resolution melting (HRM) analysis of microsatellite loci. We tested this method on licorice, a traditional herbal medicine with a long history. Results showed that nine simple sequence repeat (SSR) markers produced distinct melting curve profiles for the five licorice species investigated using HRM analysis. These results were validated by capillary electrophoresis. We applied this protocol to commercially available licorice products, thus enabling the consistent identification of 11 labels with non-declared Glycyrrhiza species. This novel strategy may thus facilitate DNA barcoding as a method of identification of closely related species in herbal medicine products. Based on this study, a brief operating procedure for using the SSR-HRM protocol for herbal authentication is provided.

Herbal medicines: challenges in the modern world. Part 3. China and Japan

INTRODUCTION

Medicinal plants, and formulations prepared from them, have been used in China and Japan for thousands of years. Nowadays, ancient formulations of Traditional Chinese and Kampo (Japanese) Medicines coexist with Western herbal medicines (HMs) and complement each other. HMs are used for the treatment of mild and chronic diseases, as an adjunct therapy, to improve wellbeing and delay aging, or as healthy (functional) foods.

AREAS COVERED

This article, a third part in a series of reviews, is focusing on history, use and regulation of the traditional and modern HMs in Japan and China. Materials available from legislative and governmental websites, PubMed and news media were used. Expert commentary: HMs are heavily regulated in both countries, often in a similar manner as conventional pharmaceutical drugs. The majority of herbal formulations are sold as over-the-counter medications supplied with leaflets describing indications and appropriate dosages for patients of different ages. Medical practitioners prescribe herbal formulations that are tailored to the needs of particular patients. Both countries had problems with adverse drug reactions and toxicity of single herbs and herbal formulations that have been investigated by authorities, and some drugs have been removed from the market.

Case reports of aconite poisoning in mainland China from 2004 to 2015: A retrospective analysis

Aconitum species have long been used in key traditional medicines in China, but cases of fatal aconite poisoning have also been reported. This paper presents a review of 40 single and multi-person cases of fatal aconite poisoning. The cases involved 53 victims in mainland China described in 27 case reports published between January 2004 and September 2015. We summarize the details of the case reports in order to highlight the features of fatal aconite-poisoning cases in China, including victims' sex and age, route of intoxication, clinical symptoms, medicolegal autopsy findings, and results of toxicological analysis. Our results indicate a need for legal medical experts encountering cases of fatal aconite poisoning to pay increased attention to the methods used for collecting biological samples. In addition, prevention strategies should focus on increasing public awareness regarding the potential toxicity of Aconitum, harm caused by medicinal liquors containing aconitine, and possibility of Aconitum alkaloids accumulating in the body.

Panax ginseng inhibits intestinal absorption of toxic Aconitum carmichaeli alkaloids in Vitro

OBJECTIVE

To evaluate the rationality and compatibility of Shenfu Formula (, SFF), a typical Chinese medicine (CM) comprised of Panax ginseng and Aconitum carmichaeli.

METHODS

Caco-2 cells were used to study the permeability of Aconitum carmichaeli marker compounds when the CM preparation was combined with Panax ginseng. P-glycoprotein (P-gp) activity and protein as well as multidrug resistance 1 (MDR1) mRNA were analyzed with rhodamine123 efflflux, western blot and real time quantitative polymerase chain reaction.

RESULTS

Aconitine (AC), mesaconitine (MA), hypaconitine (HA) and fifive other active alkaloids in Aconitum carmichaeli were selected as marker compounds. Panax ginseng inhibited intestinal absorption of highly toxic AC, MA and HA from Aconitum carmichaeli in Caco-2 cells. P-gp and breast cancer resistance protein (BCRP) were observed to be involved in AC, MA and HA efflflux. Panax ginseng induced P-gp activity in Caco-2 cells via increased MDR1/P-gp expression. Thus, Panax ginseng facilitated P-gp-mediated efflflux of toxic Aconitum carmichaeli alkaloids and restricted their intestinal absorption without inflfluencing other active components.

CONCLUSION

Future studies to elucidate mechanism of reduced toxicity of Aconitum carmichaeli when combined with Panax ginseng will guide future formula optimization.

Exploring processing adjuvants' influence on traditional Chinese medicine compatibility of Aconiti Radix Cocta and Pinelliae rhizome using rapid resolution liquid chromatography-quadrupole time-of-flight mass spectrometry

Background:

It is known that when crude Pinelliae rhizome and Pinelliae rhizoma preparatum are combined with Aconiti Radix Cocta respectively, the toxicity of the combination varies. However, the component's transformation between different compatibility have remained unclear.

Objective:

In this paper, a novel approach using rapid resolution liquid chromatography-quadrupole time-of-flight mass spectrometry (RRLC-Q-TOF-MS) coupled with multivariate statistical analysis was established for exploring the influence of processing adjuvants (PAs) on the compatibility of Aconiti Radix Cocta and Pinelliae rhizome.

Materials and Methods:

In order to obtain information about the representative markers between different groups, an exhaustive study of different protocols based on adding or removing different PAs step by step was carried out and the influence of PAs on compatibility was investigated.

Results:

It was found that lime can facilitate diester diterpenoid alkaloids with high toxicity in Aconiti Radix Cocta to be converted into low-toxic or non-toxic derivatives. Glycyrrhizae Radix et Rhizoma had no remarkable effect on the process.

Conclusion:

The established method in this study will be of great significance to process research mechanism and study on traditional Chinese Medicine compatibility and clinical application.

The growing use of herbal medicines: issues relating to adverse reactions and challenges in monitoring safety

The use of herbal medicinal products and supplements has increased tremendously over the past three decades with not less than 80% of people worldwide relying on them for some part of primary healthcare. Although therapies involving these agents have shown promising potential with the efficacy of a good number of herbal products clearly established, many of them remain untested and their use are either poorly monitored or not even monitored at all. The consequence of this is an inadequate knowledge of their mode of action, potential adverse reactions, contraindications, and interactions with existing orthodox pharmaceuticals and functional foods to promote both safe and rational use of these agents. Since safety continues to be a major issue with the use of herbal remedies, it becomes imperative, therefore, that relevant regulatory authorities put in place appropriate measures to protect public health by ensuring that all herbal medicines are safe and of suitable quality. This review discusses toxicity-related issues and major safety concerns arising from the use of herbal medicinal products and also highlights some important challenges associated with effective monitoring of their safety.

A novel concept for detoxification: complexation between aconitine and liquiritin in a Chinese herbal formula ('Sini Tang')

ETHNOPHARMACOLOGICAL RELEVANCE

Sini Tang (SNT) is a traditional Chinese herbal formulation consisting of three different herbs: Aconitum carmichaelii (Fuzi), Zingiber officinale (Ganjiang), and Glycyrrhiza uralensis (Gancao). For this study, we modified this mixture by adding the bark of Cinnamomum cassia (Rougui, ). Aconitum carmichaelii contains aconitine and its derivatives, all of which are highly toxic alkaloids. These compounds are commonly detoxified with pyrolytic and hydrolytic pretreatments, such as Heishunpian, which requires repeated soaking in salt water, boiling until the roots turn black, and drying in the oven. We now demonstrate that Glycyrrhiza uralensis, which is often used in Traditional Chinese Medicine for detoxification, reduces the concentration of free aconitine in decoctions by forming a complex between liquiritin and aconitine.

MATERIALS AND METHODS

Aqueous extracts of SNT, each individual herb or herbal mixture, and methanolic extracts of individual herbs were tested for free aconitine by HPLC coupled with a diode array detector. A detected complex was investigated by NMR and UV/vis spectroscopy. The continuous variations method and (1)H-NMR titrations provided the complex stoichiometry and binding constant. A 2D-ROESY experiment was performed to obtain the structural details of the formed complex.

RESULTS

A fast and simple HPLC method was developed to determine the amounts of aconitine and its derivatives found in herbal extracts. The Heishunpian pretreatment led to nearly complete pyrolysis and hydrolysis of the toxic compounds. However, in some batches, considerable amounts of aconitine remained. The addition of Glycyrrhiza uralensis to Aconitum carmichaelii, or liquiritin to free aconitine, led to a complexation with aconitine. The complex possessed a 1:1 stoichiometry and a binding constant of ca. 3000 L/mol to 4000 L/mol in mixtures of aqueous methanol.

CONCLUSIONS

A new HPLC based method allows the concentration of toxic aconitine and other diester diterpene alkaloids in herbal extracts to be rapidly determined. This method provides a starting point for the development of routine quality control procedures. The complexation of free aconitine by adding an excess of Glycyrrhiza uralensis or free liquiritin to SNT formulations will make these formulations safer.

Quantification of aconitine in post-mortem specimens by validated liquid chromatography-tandem mass spectrometry method: three case reports on fatal 'monkshood' poisoning

The diester-diterpene alkaloid aconitine was quantified by liquid chromatography-tandem mass spectrometry in post-mortem specimens of three cases where suicidal ingestion of Aconitum napellus L. ('monkshood') was supposed. In an attempt at rationalization, sample preparation and chromatographic conditions of plasma/serum drug analysis routine were utilized. Linearity was established from 0.5 to 20 µg L⁻¹ using newborn calf serum (NCS) as a surrogate calibration matrix for all sample types and mesaconitine as an internal standard. Validation (selectivity, sensitivity, precision, accuracy, recovery of the extraction procedure, matrix effect, processed sample stability) confirmed the applicability of the analytical method to various post-mortem matrices. Internal standard selection was based on multi-matrix process efficiency data. In human post-mortem peripheral blood a lower limit of quantification of 0.51 µg L⁻¹ and a limit of detection of 0.13 µg L⁻¹ were accomplished (0.1 ml sample aliquots). Aconitine was degraded to a large extent in different sample types when being stored at +20 °C for 30 days, while at -20 °C and for some matrices also at +4 °C no appreciable degradation occurred. Aconitine concentrations in real samples were 10.3-17.9 µg L⁻¹ (peripheral blood, n = 3), 14.9-87.9 µg L⁻¹ (heart blood, n = 3), 317-481 µg L⁻¹ (urine, n = 2), 609-4040 µg L⁻¹ (stomach content, n = 3), 139-240 µg L⁻¹ (bile, n = 2), 8.4 µg L⁻¹ (vitreous humor, n = 1), 54.7 µg L⁻¹ (pericardial fluid, n = 1), 492 µg kg⁻¹ (liver, n = 1), 15.2-19.7 mg L⁻¹ (unknown liquids secured onsite, n = 3). Together with concomitant circumstances the analytical data provided compelling evidence for acute Aconitum poisoning as being the cause of death.

Evidence-based toxicity evaluation and scheduling of Chinese herbal medicines

ETHNOPHARMACOLOGICAL RELEVANCE

While there is an increasing number of toxicity report cases and toxicological studies on Chinese herbal medicines, the guidelines for toxicity evaluation and scheduling of Chinese herbal medicines are lacking.

AIM

The aim of this study was to review the current literature on potentially toxic Chinese herbal medicines, and to develop a scheduling platform which will inform an evidence-based regulatory framework for these medicines in the community.

MATERIALS AND METHODS

The Australian and Chinese regulations were used as a starting point to compile a list of potentially toxic herbs. Systematic literature searches of botanical and pharmaceutical Latin name, English and Chinese names and suspected toxic chemicals were conducted on Medline, PubMed and Chinese CNKI databases.

RESULTS

Seventy-four Chinese herbal medicines were identified and five of them were selected for detailed study. Preclinical and clinical data were summarised at six levels. Based on the evaluation criteria, which included risk-benefit analysis, severity of toxic effects and clinical and preclinical data, four regulatory classes were proposed: Prohibited for medicinal usage, which are those with high toxicity and can lead to injury or death, e.g., aristolochia; Restricted for medicinal usage, e.g., aconite, asarum, and ephedra; Required warning label, e.g., coltsfoot; and Over-the-counter herbs for those herbs with a safe toxicity profile.

CONCLUSION

Chinese herbal medicines should be scheduled based on a set of evaluation criteria, to ensure their safe use and to satisfy the need for access to the herbs. The current Chinese and Australian regulation of Chinese herbal medicines should be updated to restrict the access of some potentially toxic herbs to Chinese medicine practitioners who are qualified through registration.