Chinese proprietary medicine in Singapore: regulatory control of toxic heavy metals and undeclared drugs

Perceptions and uses of plants for reproductive health among traditional midwives in Ecuador: moving towards intercultural pharmacological practices

Despite the fact that plants have played an important role in midwifery in many cultures, there are very few in-depth studies on the plants traditionally used by midwives. The aim of this study is to analyse the perceptions and the uses of medicinal plants for reproductive health among indigenous midwives in the city of Otavalo, Ecuador. The article also aims to analyse the perceptions of traditional midwives regarding allopathic drugs for reproductive health and their possible overlapping uses of medicinal plants and allopathic drugs. The data are drawn from an ethnographic study carried out in Ecuador. In total, 20 traditional midwives have been interviewed. Individual and in-depth interviews also took place with a sample of 35 women as well as with five nurses and two doctors working at San Luis Hospital in Otavalo. The study shows that cultural health management and the incorporation of the beliefs and practices relating to women's reproductive health can represent a starting point towards the search for more successful strategies in reproductive health.

Harnessing traditional Chinese medicine to improve cancer therapy: issues for future development

Traditional Chinese medicine (TCM) has recently yielded a number of chemical compounds with clinically significant anticancer activity. The theory of TCM formulas, however, unlike Western medicine, is based on the interactions of the various Chinese medicinal materials in the body, rather than the activity of a single purified chemical compound. Mechanisms for the possible synergistic anticancer effects of components in TCM formulas have recently been postulated. Advanced research on the clinical effects of TCM formulas, however, has been hampered by inconsistent dosage formulations and unreliable quality control. Scientific challenges in dosage formulation and methods for ensuring quality control of TCM products will be discussed.

The Effect of Gu-Sui-Bu (Drynaria fortunei) on Bone Cell Activity

We investigated the effects of Gu-Sui-Bu using in vitro bone cell cultures. Primary rabbit and mouse marrow cells were cultured with or without five different concentrations of Gu-Sui-Bu extract. Osteoclast numbers were assessed using tartrate-resistant acid phosphatase (TRAP) positive cell counts and for function, osteoclast resorption pits on bovine bone slices were performed. Alkaline phosphatase (AP) positive cell counts and mineralized nodule formation were examined to assess osteoblast function with Gu-Sui-Bu. TRAP+ osteoclast numbers increased, as did the number and size of resorption pits with 0.001 mg/ml of extract. Low doses of extract did not alter AP+ colony number or mineralized nodule formation, but both were inhibited by doses of 0.1 mg/ml or higher. The highest dose of extract (10 mg/ml) inhibited proliferation of all cell types. At 0.01 and 0.001 mg/ml doses, RANKL increased over time; however, osteoprotegerin levels only increased at doses ≥0.1 mg/ml. Resorption pit formation was decreased without alteration in mature multinucleated (TRAP+) cell counts only at the highest dose of the putative active ingredient of Gu-Sui-Bu. In summary, lower concentrations of Gu-Sui-Bu extract had positive effects on osteoclast proliferation, survival and resorptive activity that may be mediated through enhanced prostaglandin secretion. However, high doses of extract proved detrimental to osteoclast and osteoblast survival. No effect of low doses of Gu-Sui-Bu extract was seen in osteoblast cultures. High doses of the putative active ingredient of Gu-Sui-Bu showed mild inhibition of mouse osteoclast function.

Methysticin and 7,8-dihydromethysticin are two major kavalactones in kava extract to induce CYP1A1

Kava is a plant traditionally used for making beverages in Pacific Basin countries and has been used for the treatment of nervous disorders in the United States. The pharmacological activity of kava is achieved through kavalactones in kava extract, which include kawain, 7,8-dihydrokawain, yangonin, 5,6-dehydrokawain, methysticin, and 7,8-dihydromethysticin. Recent studies have shown that kava extract induces hepatic CYP1A1 enzyme; however, the mechanisms of CYP1A1 induction have not been elucidated, and the kavalactones responsible for CYP1A1 induction have not yet been identified. Using a combination of biochemical assays and molecular docking tools, we determined the functions of kava extract and kavalactones and delineated the underlying mechanisms involved in CYP1A1 induction. The results showed that kava extract displayed a concentration-dependent effect on CYP1A1 induction. Among the six major kavalactones, methysticin triggered the most profound inducing effect on CYP1A1 followed by 7,8-dihydromethysticin. The other four kavalactones (yangonin, 5,6-dehydrokawain, kawain, and 7,8-dihydrokawain) did not show significant effects on CYP1A1. Consistent with the experimental results, in silico molecular docking studies based on the aryl hydrocarbon receptor (AhR)-ligand binding domain homology model also revealed favorable binding to AhR for methysticin and 7,8-dihydromethysticin compared with the remaining kavalactones. Additionally, results from a luciferase gene reporter assay suggested that kava extract, methysticin, and 7,8-dihydromethysticin were able to activate the AhR signaling pathway. Moreover, kava extract-, methysticin-, and 7,8-dihydromethysticin-mediated CYP1A1 induction was blocked by an AhR antagonist and abolished in AhR-deficient cells. These findings suggest that kava extract induces the expression of CYP1A1 via an AhR-dependent mechanism and that methysticin and 7,8-dihydromethysticin contribute to CYP1A1 induction. The induction of CYP1A1 indicates a potential interaction between kava or kavalactones and CYP1A1-mediated chemical carcinogenesis.

Levels of arsenic, cadmium, lead, manganese and zinc in biological samples of paralysed steel mill workers with related to controls

The determination of essential trace and toxic elements in the biological samples of human beings is an important clinical screening procedure. This study aimed to assess the possible effects of environmental exposure on paralysed male workers (n = 75) belonging to the production and quality control departments of a steel mill. In this investigation, the concentrations of arsenic, cadmium, lead, manganese and zinc were determined in biological samples (blood, urine and scalp hair samples) of exposed paralysis and non-paralysed steel mill workers. For comparative purposes, unexposed healthy subjects of same age group were selected as referents. The elements in the biological samples were measured by atomic absorption spectrophotometry prior to microwave-assisted acid digestion. The validity of the methodology was checked by the biological certified reference materials. The results indicate that the level understudy elements in all three biological samples were significantly higher in paralysed workers of both groups (quality control and production) as compared to referents (p < 0.01). The possible connection of these elements with the aetiology of disease is discussed. The results also show the need for immediate improvements of workplace ventilation and industrial hygiene practices.

Quality of herbal medicines: challenges and solutions

The popularity of herbal medicines has risen worldwide. This increase in usage renders safety issues important. Many adverse events of herbal medicines can be attributed to the poor quality of the raw materials or the finished products. Different types of herbal medicines are associated with different problems. Quality issues of herbal medicines can be classified into two categories: external and internal. In this review, external issues including contamination (e.g. toxic metals, pesticides residues and microbes), adulteration and misidentification are detailed. Complexity and non-uniformity of the ingredients in herbal medicines are the internal issues affecting the quality of herbal medicines. Solutions to the raised problems are discussed. The rigorous implementation of Good Agricultural and Collection Practices (GACP) and Good Manufacturing Practices (GMP) would undoubtedly reduce the risk of external issues. Through the use of modern analytical methods and pharmaceutical techniques, previously unsolved internal issues have become solvable. Standard herbal products can be manufactured from the standard herbal extracts.

Metals and disease: a global primary health care perspective

Metals are an important and essential part of our daily lives. Their ubiquitous presence and use has not been without significant consequences. Both industrial and nonindustrial exposures to metals are characterized by a variety of acute and chronic ailments. Underreporting of illnesses related to occupational and environmental exposures to chemicals including metals is of concern and presents a serious challenge. Many primary care workers rarely consider occupational and environmental exposures to chemicals in their clinical evaluation. Their knowledge and training in the evaluation of health problems related to such exposures is inadequate. This paper presents documented research findings from various studies that have examined the relationship between metal exposures and their adverse health effects both in developing and developed countries. Further, it provides some guidance on essential elements of a basic occupational and environmental evaluation to health care workers in primary care situations.

Heavy metal and pesticide content in commonly prescribed individual raw Chinese Herbal Medicines

Heavy metal and pesticide contamination has previously been reported in Chinese Herbal Medicines (CHMs), in some cases at potentially toxic levels. This study was conducted to determine general patterns and toxicological significance of heavy metal and pesticide contamination in a broad sample of raw CHMs. Three-hundred-thirty-four samples representing 126 species of CHMs were collected throughout China and examined for arsenic, cadmium, chromium, lead, and mercury. Of the total, 294 samples representing 112 species were also tested for 162 pesticides. At least 1 metal was detected in all 334 samples (100%) and 115 samples (34%) had detectable levels of all metals. Forty-two different pesticides were detected in 108 samples (36.7%), with 1 to 9 pesticides per sample. Contaminant levels were compared to toxicological reference values in the context of different exposure scenarios. According to a likely scenario of CHM consumption, only 3 samples (1%) with heavy metals and 14 samples (5%) with pesticides were found with concentrations that could contribute to elevated background levels of contaminant exposure. According to the most conservative scenario of CHM consumption, 231 samples (69%) with heavy metals and 81 samples (28%) with pesticides had contaminants that could contribute to elevated levels of exposure. Wild collected plants had higher contaminant levels than cultivated samples. Cadmium, chromium, lead, and chlorpyrifos contamination showed weak correlations with geographic location. Based on our assumptions of the likely mode of consumption of raw CHMs, the vast majority (95%) of the 334 samples in this study contained levels of heavy metals or pesticides that would be of negligible concern. However, given the number of samples with detectable contaminants and the range between the more likely and more conservative scenarios of contaminant exposure, more research and monitoring of heavy metals (especially cadmium and chromium) and pesticide residues (especially chlorpyrifos) in raw CHMs are advised.

Increased risks of upper tract urothelial carcinoma in male and female chinese herbalists

BACKGROUND/PURPOSE

It has been shown that herbs that contain aristolochic acid induce urological cancer. Chinese herbalists have easy access to such herbs. Our previous mortality study has shown a significantly increased risk of urological cancer in female but not male herbalists. To re-examine this risk in male herbalists, the incidence of urological cancer was analyzed.

METHODS

We enrolled all 6550 Chinese herbalists in Taiwan registered during 1985-2000, and we retrospectively followed the development of cancer until 2001 by analysis of data collected from the Taiwan Cancer Registry. Standardized incidence ratios (SIRs) were calculated for urological cancers in herbalists and compared with those for the general population in Taiwan.

RESULTS

There were 30 newly diagnosed cases of urological cancer and most of them were transitional cell carcinoma (93.1%). The mean age at diagnosis for urothelial carcinoma was 51.6 years, and 51.9% were in the upper urinary tract. After adjustment for age and sex, the SIR for all urological cancers was 3.51 [(95% confidence interval (CI): 2.37-5.01]. When stratified by location, the SIRs for kidney and upper urinary tract cancers and bladder cancer were 4.24 (95% CI: 2.47-6.80) and 2.86 (95% CI: 1.52-4.89), respectively. When analyzed by sex, the SIRs for all urological cancers, kidney and upper urinary tract cancers, and bladder cancer were also significantly increased in male herbalists.

CONCLUSION

The significant risk of urothelial carcinoma noted in male herbalists increases our suspicion that this is an occupational disease that renders regular health assessment of herbalists an urgent necessity.

Rapid detection and identification of counterfeit and [corrected] adulterated products of synthetic phosphodiesterase type-5 inhibitors with an atmospheric solids analysis probe

The market success of the three approved synthetic phosphodiesterase type-5 (PDE-5) inhibitors for the treatment of erectile dysfunction has led to an explosion in counterfeit versions of these drugs. In parallel a large market has developed for herbal products claimed to be natural alternatives to these synthetic drugs. The herbal products are heavily advertised on the internet and are freely available to purchase without prescription. Furthermore, adulteration of these supposed natural medicines is a very common and serious phenomenon. Recent reports have shown that the adulteration has extended to the analogues of the three approved synthetic PDE-5 inhibitors. An Atmospheric Solids Analysis Probe (ASAP) was used for the direct analysis of the counterfeit pharmaceuticals and herbal products. Using the ASAP combined with time-of-flight mass spectrometry (TOF MS) it was possible to detect fraudulent counterfeit tablets. The physical appearance of the pills resembled the pills from the original manufacturer but contained the wrong active pharmaceutical ingredient (API). Detecting adulteration for five herbal supplements marketed as natural alternatives to PDE-5 inhibitors was also possible using the ASAP. Three types of adulteration were found in the five samples: adulteration with tadalafil or sildenafil, mixed adulteration (tadalafil and sildenafil), and adulteration with analogues of these drugs.

Analytical methods for heavy metals in herbal medicines

INTRODUCTION

It is estimated that about 70-80% of the world's population relies on non-conventional medicine, mainly of herbal origin. However, owing to the nature and sources of herbal medicines, they are sometimes contaminated with toxic heavy metals such as lead, arsenic, mercury and cadmium, which impose serious health risks to consumers. It is critical to analyse source materials for heavy metals in order to ensure that their concentrations meet the related standards or regulations limiting their concentrations in herbal medicines. In this review, different analytical methods for analysis of heavy metals in herbal medicines are discussed.

OBJECTIVE

To provide a comprehensive review of the current state of the art in analytical methods used to detect heavy metals in herbal medicines.

METHODOLOGY

We systematically searched and reviewed the research articles regarding analytical methods for heavy metals in herbal medicine from various databases, such as Medline/PubMed, ScienceDirect, SciFinder, Google Scholar, EBSCO, Gale InfoTrac, Ingenta, Ovid, ProQuest and ISI Web of Knowledge.

RESULTS

In this review, we discuss in detail several commonly used and sensitive analytical techniques, including atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry or mass spectrometry, X-ray fluorescence spectrometry, high-performance liquid chromatography, differential pulse polarography, neutron activation analysis and anodic stripping voltammetry. We also provide some application examples of these analytical techniques for heavy metals in herbal medicines.

Detection and characterization of synthetic steroidal and non-steroidal anti-inflammatory drugs in Indian ayurvedic/herbal products using LC-MS/TOF

It is claimed that ayurvedic/herbal healthcare products (AHPs) are safe because of their natural origin. However, several reports exist of adulteration of AHPs with synthetic drugs. In this study, a generalized strategy was developed using LC-MS/TOF for the detection and verification of steroidal and anti-inflammatory drugs in 58 AHPs collected from various parts of India. The strategy involved recording of mass spectral information for standard drugs-including ionization mode (ESI/APCI - ve or + ve), mass spectrum, accurate mass, identification of qualifier fragments (two), extracted ion chromatograms (EICs), isotopic pattern and determination of UV max (nm)-through UV-PDA studies. Adulteration was then detected in AHPs primarily through comparison of EICs at accurate m/z for molecular ion peaks and R(T) matching with the standard. It was confirmed by spiking with the standards, and matching mass spectrum, accurate mass, R(T) of qualifier fragments, isotopic pattern and UV spectrum of the standards with the adulterant peaks in AHPs. Dexamethasone and diclofenac were detected as adulterants in ten AHPs whereas one AHP tested positive for piroxicam and another for dexamethasone. All the adulterated products were sold by the healthcare practitioners, while no product marketed by manufacturers or chemist shops had this problem. The study showed that LC-MS/TOF-based screening could be used as a rapid approach to monitor adulteration of steroids and anti-inflammatory drugs in AHPs.

Preliminary investigation of metal and metalloid contamination of homeopathic products marketed in Croatia

BACKGROUND

Due to their popularity as a complementary therapy in many diseases, homeopathic products of animal, vegetable, mineral and chemical origin should be tested for the presence of contaminants to prevent eventual toxic effects.

OBJECTIVE

Thirty samples of homeopathic products were analyzed to estimate possible contamination with potentially toxic elements: Pb, Cd, As, Hg, Cr, Ni and Zn, and to assess human exposure to these metals/metalloid as a consequence of their consumption.

METHODS

Atomic absorption spectrometry was used to determine metal and metalloid concentrations.

RESULTS

Most tested products had very low metal/metalloid levels (below the limit of quantification of the method), but the metal/metalloid levels in the remaining products were in the following ranges (in microg g(-1)): Pb 0.33-1.29 (6 samples), Cd 2.78 (1 sample), As 0.22 (1 sample), Hg 0.02-0.12 (24 samples), Cr 0.40-10.27 (10 samples), Ni 0.43-55.00 (19 samples), and Zn 2.20-27.80 (11 samples). In the absence of regulatory standards for homeopathic products, the obtained results were compared to maximum allowable levels (MALs) as proposed by USP Ad Hoc Advisory Panel. Some analyzed preparations had metal levels above MALs (Pb: 2 samples; Cd: 1 sample; Ni: 2 samples). However, estimated cumulative daily intakes from tested homeopathic products were in all cases lower than permitted daily exposures for all dosage forms.

CONCLUSION

The risk of bioaccumulation of metals/metalloid from the homeopathic medicines seems to be rather low, due to small quantities of those products prescribed to be applied per day, as well as insignificant metal contamination of the majority of tested products. However, the fact that particular formulations were contaminated by metals above MALs indicates potential risk and points to the necessity of regular monitoring of homeopathic products for metal contamination, due to their frequent and mostly unsupervised use.

Determination of lead content in medicinal plants by pre-concentration flow injection analysis-flame atomic absorption spectrometry

INTRODUCTION

Although medicinal plants are widely used throughout the world, few studies have been carried out concerning the levels of heavy metal contaminants present. Such metals are highly toxic to living organisms even in low concentrations owing to their cumulative effect. The present paper describes the the development of a pre-concentration flow injection analysis-flame atomic absorption spectrometric system to determine the lead content in medicinal plants at the ppb level.

OBJECTIVE

To develop a pre-concentration flow injection analysis-flame atomic absorption spectrometric system to determine the lead content in medicinal plants at the ppb level.

METHODOLOGY

A pre-concentration flow system was coupled to a flame atomic absorption spectrometer. The plant samples were analysed after nitroperchloric digestion. The proposed system was optimised by evaluating the following parameters: nature, concentration and volume of the eluent solution, elution flow rate, elution efficiency, pre-concentration flow rate and pre-concentration time.

RESULTS

The proposed system exhibited good performance with high precision and repeatability (RSD < or = 2.36%), excellent linearity (r = 0.9999), low sample consumption (10.5 mL per determination) and an analytical throughput of 55 samples/h. Lead concentrations ranged from 3.37 + or - 0.25 to 7.03 + or - 0.51 microg/g in dry material. This concentration interval is greater than that previously published in the literature.

CONCLUSION

The inclusion of a pre-concentration column in the flow manifold improved the sensitivity of the spectrometer. Thus, it was possible to determine the analyte at the ng/mL level in sample solutions of medicinal plants. This is a very important accomplishment, especially when the cumulative effect of heavy metals in living organisms is considered.

The state of dietary supplement adverse event reporting in the United States

PURPOSE

The Dietary Supplements Information Expert Committee (DSI-EC; the Committee) of the United States Pharmacopeial Convention (USP) reviews safety profiles of dietary supplements before development of USP-National Formulary (USP-NF) quality monographs. Because the veracity of dietary supplement adverse event reports (DS AERs) directly affects DSI-EC safety reviews, the Committee reviewed the current status of DS AER reporting in the US.

METHODS

DSI-EC reviewed PubMed searches, information from the US Food and Drug Administration's (FDA) MedWatch program, the Toxic Exposure Surveillance System (TESS) of the American Association of Poison Control Centers (AAPCC), and reports from US and other agencies. DSI-EC analyzed this information to identify key factors that affect the quality of DS AERs.

RESULTS

The overall incidence of DS AERs appears generally to be low. However, the primary reporting portal (FDA MedWatch) receives fewer AERs than do poison control centers (PCCs), and limited coordination exists among national and international surveillance programs for evaluating signals that may indicate potential public health risks. Both inadequate and poor-quality reporting of DS AERs are major limitations of DS safety monitoring in the US.

CONCLUSIONS

Based on its assessments, the Committee advances recommendations to improve the quality of reporting, monitoring, and assessing DS AERs. These include (1) enhanced data collection approaches, (2) improved coordination of AER surveillance programs, (3) strengthening of educational programs for public and health care sectors, and (4) conduct of research concerning the safety of DS. If taken, these approaches are expected to improve the health and well-being of DS users.

Herbal and dietary supplement disclosure to health care providers by individuals with chronic conditions

BACKGROUND

Very little is known about herbal and dietary supplement disclosure in adults with chronic medical conditions, especially on a national level.

OBJECTIVE

To examine herbal and dietary supplement disclosure to conventional health care providers by adults with chronic medical conditions.

DESIGN

Data on herbal and dietary supplement use (N = 5456 users) in the previous year were used from the 2002 National Health Interview Survey. Bi-variable analyses compared characteristics between herbal and dietary supplement disclosers and nondisclosers. Multivariable logistic regression identified independent correlates of herbal and dietary supplement disclosure.

RESULTS

Overall, only 33% of herbal and dietary supplement users reported disclosing use of herbal and dietary supplements to their conventional health care provider. Among herbal and dietary supplement users with chronic conditions, less than 51% disclosed use to their conventional health care provider. Hispanic (adjusted odds ratio and 95% confidence interval = 0.70 [0.52, 0.94]) and Asian American (adjusted odds ratio and 95% confidence interval = 0.54 [0.33, 0.89]) adults were much less likely than non-Hispanic white Americans to disclose herbal and dietary supplement use. Having less than a high school education (adjusted odds ratio and 95% confidence interval = 0.61 [0.45, 0.82]) and not having insurance (adjusted odds ratio and 95% confidence interval = 0.77 [0.59, 1.00]) were associated with being less likely to disclose herbal and dietary supplement use.

CONCLUSION

Herbal and dietary supplement disclosure rates are low, even among adults with chronic conditions. These findings raise concerns about the safety of herbal and dietary supplements in combination with allopathic care. Future studies should focus on educating physicians about crosscultural care as well as eliciting information about herbal and dietary supplement use.

Increased mortality risk for cancers of the kidney and other urinary organs among Chinese herbalists

BACKGROUND

A national survey in Taiwan has shown that Chinese herbal therapy increases the risk of chronic kidney disease. However, it is unknown whether herbal therapy will increase the risk of urological cancers. The purpose of this study was to determine whether Chinese herbalists are at higher risk for urological cancers.

METHODS

We studied all Chinese herbalists in Taiwan that were registered in the Chinese Herbalist Labor Union between 1985 and 2000. We retrospectively followed their survival status and causes of death using the National Mortality Registry Database from 1985 to 2004. Standardized mortality ratios (SMRs) for urological cancers in herbalists were calculated and compared with those of the general population of Taiwan.

RESULTS

A total of 6548 Chinese herbalists were enrolled and 88,289 person-years were accrued during the observation period. After adjustment for age and sex, the SMR for urological cancers was significantly higher for Chinese herbalists than for the general population (SMR = 3.10; 95% CI: 1.41-5.87). When further stratified by location, the SMR for kidney cancer and other urinary organ cancers (SMR = 3.81; 95% CI: 1.39-8.28) except bladder cancer (SMR = 2.26; 95% CI: 0.47-6.59) were significantly higher for the Chinese herbalists. The SMR for chronic and unspecified nephritis, renal failure, and renal sclerosis were also significantly higher for herbalists (SMR = 2.40; 95% CI: 1.40-3.84).

CONCLUSIONS

Chinese herbalists have a significantly higher risk for urological cancers. This increased risk among herbalists highlights the urgent need for safety assessments of Chinese herbs.

Assessment of heavy metal exposure via the intake of oriental medicines in Korea

Oriental medical herbs are mainly natural products that are generated by simple processes, and therefore there is the possibility of contamination with various pollutants, including heavy metals. Heavy metals produce adverse effects in humans, and the toxicities of lead (Pb) and cadmium (Cd) are well established. This study evaluated the effects of exposure to Pb and Cd via the intake of the frequent prescriptions of oriental medicines, and assessed the risk to the Korean population based on domestic data. The average daily exposures to Pb and Cd were estimated. This is the first study to evaluate exposure and risk of heavy metal intoxication through intake of oriental medicines in Korea. Despite the uncertainties and limits of the data, these results simulate realistic exposure levels.

Impurities in Herbal Substances, Herbal Preparations and Herbal Medicinal Products, IV. Heavy (Toxic) Metals

The main source of available forms of heavy metals (toxic metals) for the plant kingdom is anthropogenic, resulting from diverse activities such as metallurgic processing of ore, cement plants, uncontrolled discharge of sewage sludge, burning of fossil fuels and waste incineration plants, and leaded petrol. Agricultural chemicals (e.g. phosphate fertilizers containing cadmium) may also contribute to the contamination of cultivated plants. The main threats to human health from toxic metals are associated with exposure to lead, cadmium, mercury (organic forms, especially methylmercury) and arsenic (mineral form only), which have no known vital or beneficial effect on living organisms. As their toxicity often takes years to manifest and may go unsuspected, their toxicological risk is defined on the basis of the so-called Provisional Tolerable Weekly Intake (PTWI) values. Beside anthropogenic causes, the main factors that may lead to high levels of toxic metals in medicinal plants are their availability in the soil with soil pH as the most important parameter for uptake by the plant. Indeed, genetic features of certain plant species show a tendency to accumulate certain trace elements, especially cadmium (“cadmium collector”). A very recent revision draft of the monograph “Herbal drugs” (Ph. Eur., 1433) includes acceptance criteria for lead, cadmium and mercury. This proposal is discussed in detail, based on literature data dealing with terrestrial plants and seaweed. Additionally, the need for inclusion of tests for inorganic impurities in quality control specification is examined, based on a risk assessment. As the daily intake of food supplements is very similar to the one of herbal remedies, it would be advisable to take into account the same acceptance criteria. The specific situation has also been considered of exotic herbal remedies, particularly those of Asian origin, which have been repeatedly reported to contain toxic levels of heavy metals and/or arsenic resulting in heavy metal poisoning.

Fabrication and evaluation of a new composite composed of tricalcium phosphate, gelatin, and Chinese medicine as a bone substitute

This study investigates the biological effects of traditional Chinese medicines on the activities of bone cells using rat bone cells. Then, a mixture of a GGT composite, that is, a novel biodegradable composite containing genipin crosslinked gelatin and tricalcium phosphate, and traditional Chinese medicine (TCM) was prepared as a GGT-TCM composite. A cultured neonatal rat calvarias organ was used to measure the potential of GGT-TCM composite for use in promoting the regeneration of defective bone tissue. The mitochondria activity of the bone cells following exposure to various concentrations of crude extracts of five herbal Chinese medicines was measured by colorimetric assay. Biochemical markers, such as alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) titers were analyzed to evaluate the activities of bone cells. Finally, we examined the organ culture units, which were maintained in cultured medium for 5 weeks. Morphology of tissue was observed, and the quantitative evaluation of the regenerated bone was determined. In a bone cells culture experiment, adding Cuscuta chinensis Lam. (TCM-5) to the bone cells culture clearly promoted the proliferation and differentiation of the osteoblasts from their precursor cells; but the reduced amount of TRAP indicated that the medicine significantly inhibited the osteoclasts activities. Opposite bone cell responses were observed when Loranthus parasiticus Merr. (TCM-3) and Achyranthes bidentata Bl. (TCM-4) were added to the bone cells culture. Eucommia ulmoides Oliv. (TCM-1) and Dipsacus asper Wall. (TCM-2) potentially influence the proliferation and differentiation of the osteoblasts from their precursor cells, but they did not affect the osteoclasts activities. The finding from the organ culture indicated that Chinese medicine effectively increased the rate of tissue regeneration of damaged bones.

A novel bone substitute composite composed of tricalcium phosphate, gelatin and drynaria fortunei herbal extract

The Chinese herb, Gu-Sui-Bu (GSB) (Drynaria fortunei J. Sm.) has been anecdotally reported to enhance bone healing. We had previously confirmed in vitro the efficacy and safety of GSB in bone healing, and showed that it influenced both osteoblast and osteoclast activity. For clinically useful application of these bone regenerative effects, a satisfactory delivery system for GSB is required. In this study, we determined the optimal concentration of GSB for regenerative activity in rat bone cells via MTT, alkaline phosphatase (ALP), nodule formation and TRAP assays, and designed and tested a GSB-rich bone composite material. The composite was fabricated by mixing a biodegradable GGT composite, containing genipin cross-linked gelatin and tricalcium phosphate, with the predetermined concentration of GSB (GGT-GSB). Neonatal rat calvarial culture and animal implantation were employed to evaluate and compare in vitro and in vivo the potential of GGT-GSB and GGT in regeneration of defective bone tissue. The most effective concentration of GSB was 100 mug/mL, which significantly increased osteoblast numbers, intracellular ALP levels and nodule numbers, without influencing osteoclast activity. In vitro and in vivo tests also showed that GGT-GSB accelerated bone regeneration compared to GGT. GGT-GSB thus has great potential for improved bone repair.

Protocols on safety, efficacy, standardization, and documentation of herbal medicine (IUPAC Technical Report)

This Technical Report compiles and analyzes the current scientific knowledge on herbal medicine and highlights the practical ways for ensuring the safety of herbal preparations and evaluating their claimed efficacy. Emphasis has been given to the methods for standardization of herbal medicine and the ways and means for moving forward to achieve the difficult goal of preparing herbal medicines of consistent quality and effects. Pragmatic approaches have been recommended to overcome the difficulties in (i) protecting intellectual property rights (IPR); (ii) producing safe, potent, standardized, and affordable herbal medicine; and (iii) documenting the knowledge base on herbal medicine in an easily accessible format.

Public health risks from heavy metals and metalloids present in traditional Chinese medicines

Out of 247 traditional Chinese medicines (TCM) investigated, a proportion were contaminated with arsenic (5-15%), lead (approximately 5%), and mercury (approximately 65%). Some preparations exceeded the tolerable daily intake (TDI) for males and females for arsenic (4 and 5 products, respectively), lead (1 and 2 products), and mercury (5 and 7 products). These exceedances were as high as 2760-fold, which posed a potential danger to public health. As many users are known to self-prescribe, there is a substantial risk of poisoning from the consumption of these contaminated TCM.

DNA methods for identification of Chinese medicinal materials

As adulterated and substituted Chinese medicinal materials are common in the market, therapeutic effectiveness of such materials cannot be guaranteed. Identification at species-, strain- and locality-levels, therefore, is required for quality assurance/control of Chinese medicine. This review provides an informative introduction to DNA methods for authentication of Chinese medicinal materials. Technical features and examples of the methods based on sequencing, hybridization and polymerase chain reaction (PCR) are described and their suitability for different identification objectives is discussed.

Heavy metal hazards of Nigerian herbal remedies

The uses of herbal products are not regulated in Nigeria and in many low-income countries and are freely available to everyone. The safety of these herbal medicines is poorly understood. This study characterizes the content of cadmium, copper, iron, nickel, selenium, zinc, lead and mercury in a random sample of Nigerian traditional products. Ready-to-use herbal products were purchased from the open market and digested using HNO3.The heavy metal content of the digested filtrate was determined by atomic absorption spectrometry Uni-cam Model 929. The result showed that 100% of the samples contained elevated amounts of heavy metals. These data alert us to the possibility of heavy metal toxicity from herbal products in Nigeria. The public health hazards from ingestion of herbal medicines should be identified and disclosed by in-depth risk assessment studies.

[Lead poisoning from traditional Indian medicines]

BACKGROUND

The use of traditional remedies is spreading rapidly in developed countries. Although it is commonly thought that such medications are not harmful because they are of natural origin, they often contain dangerous ingredients, especially heavy metals. Several cases of poisoning, mainly lead poisoning, have been published, but none to our knowledge in France. We recently observed a case of lead poisoning in a man who had been taking ayurvedic remedies.

CASE

A 32-year-old man was repeatedly hospitalized for paroxysmal abdominal pain with constipation, weight loss, anemia, and mild elevation of liver enzyme levels. Four months after the initial admission, blood lead measurement showed heavy metal poisoning. The patient was treated with a chelating agent and recovered uneventfully. Investigation revealed that the lead source was self-medication with an ayurvedic remedy, a powder used for four weeks before the first hospitalization.

DISCUSSION

To our knowledge this is the first reported French case of lead poisoning due to a traditional remedy. The problem is undoubtedly more widespread, however, for use of traditional remedies is growing more here, and many of them contain dangerous ingredients. Patients from communities known to use traditional medicines or recently returned from countries where such treatments are widespread should be directly questioned about their use of these remedies, because this information will not usually be volunteered. Information directed at populations at risk is also advisable, for most users are unaware that so-called 'natural' medicines can be dangerous.

Anorectic sibutramine detected in a Chinese herbal drug for weight loss

In the presented case, a young healthy woman had ordered a Chinese herbal medicine, called "LiDa Dai Dai Hua Jiao Nang", via internet. She took this product for approximately 1 week, but on the second day she developed severe headache, vertigo and sensation of numbness. After discontinuing medication, symptoms disappeared within 2 days. For identification of the ingredients, a urine sample as well as a sample of the "LiDa" capsule were analysed by GC-MS and HPLC-DAD. One major ingredient was detected in urine as well as in the "LiDa" capsule and was identified as sibutramine. Quantification by HPLC-DAD yielded 27.4 mg sibutramine base, which is approximately two times the amount of the highest authorized single dose available on the pharmaceutical market in Germany. This case demonstrates a common problem with herbal medicines, where adulterations with synthetic therapeutic substances can lead to severe side effects and/or potentially fatal interactions with conventional medicines.

Metal content of ephedra-containing dietary supplements and select botanicals

PURPOSE

The metal content of dietary supplements, including 13 ephedra-containing supplements, was studied.

METHODS

Samples of botanicals (black cohosh, echinacea, goldenseal, kava kava, milk thistle, saw palmetto, Synephrine, and valerian root), ephedra-containing dietary supplements (Amp II, EPH 833, Ephedra, Ephedra 1000, Hydroxycut, Metabolife 356, Metabolift, Ripped Fuel, Ripped Fuel Extreme, Ripped Fuel [ma huang-free], Stacker 2 [two lots], Super Stinger, Virgin Earth, Xenadrine RFA-1 [two lots], Yellow Jacket), and nonprescription reference agents (NoDoz and Primatene) were digested in acid, reacidified, and then spiked with internal standards. Metals were quantified using Environmental Protection Agency quality assurance and quality-control standards 6020 and 200.8. Forty-seven metals were analyzed by inductively coupled plasma-mass spectrometry, with subpart-per-trillion detection limits.

RESULTS

All metals detected were in concentrations below toxic levels or physiological limit levels for the daily doses specified by the products' labeling. Metals found in highest concentrations among all the supplements sampled were sodium, magnesium, calcium, potassium, aluminum, iron, titanium, mercury, strontium, lead, barium, and silver. Of the 27 supplements analyzed, those with the lowest metal concentrations were mostly single-ingredient botanical supplements, while multiple-component, ephedra-containing dietary supplements generally had higher metal concentrations. Significant lot-to-lot variations were found for two ephedra-containing dietary supplements.

CONCLUSION

None of 47 metals was found in highly toxic amounts in 23 brands of dietary supplements and two nonprescription reference preparations.

Herbs or natural substances as complementary therapies for chronic kidney disease: ideas for future studies

Chronic kidney disease (CKD) is an increasingly common condition with limited treatment options that is placing a major financial and emotional burden on the community. The use of complementary and alternative medicines (CAMS) has increased many-fold over the past decade. Although several compelling studies show renal toxicities and an adverse outcome from use of some CAMS, there is also emerging evidence in the literature that some may be renoprotective. Many nephrologists are unaware of these potential therapeutic benefits in treating CKD, or they are reluctant to consider them in research trials for fear of adverse effects (including nephrotoxicity) or deleterious interaction with co-prescribed, conventional medicines. The increased use of self-prescribed CAMS by their patients suggests that practitioners and researchers should keep abreast of the current information on these agents. A primary goal of this article was to review the available scientific evidence for the use of herbs or natural substances as a complementary treatment for patients with CKD. A further goal was to report the literature on herbs that have been reported to cause kidney failure.

Managing nonmalignant chronic abdominal pain and malignant bowel obstruction

Evaluation of abdominal pain requires an understanding of the possible causes(benign or malignant) and recognition of typical patterns and clinical presentation. Abdominal pain has multiple causes; associated signs and symptoms may aid in the diagnosis. Remember that some patients will not have a textbook presentation, and unusual causes for pain must be considered. Those with chronic pancreatitis with structural complications should be operated on early, whereas those with other types of chronic pancreatitis should receive medical therapy focusing on alleviating symptoms. Control of the most troublesome symptoms will provide the best management for IBS. Pharmacologic success in bowel obstruction depends on the level and degree of obstruction. Decision making is based on reasonable expectations of survival, treatment-related success, performance status, and goals of care. Quality of life will be enhanced by appropriate symptom management.

Herbal medicines for treatment of irritable bowel syndrome

BACKGROUND

Traditional herbal therapies have been used for a long time to treat gastrointestinal disorders including irritable bowel syndrome, and their effectiveness from clinical research evidence needs to be systematically reviewed.

OBJECTIVES

To assess the effectiveness and safety of herbal medicines in patients with irritable bowel syndrome.

SEARCH STRATEGY

We searched the following electronic databases till July 2004: The Cochrane Library (CENTRAL), MEDLINE, EMBASE, AMED, LILACS, the Chinese Biomedical Database, combined with hand searches of Chinese journals and conference proceedings till end of 2003. No language restriction was used.

SELECTION CRITERIA

Randomised controlled trials of herbal medicines compared with no treatment, placebo, pharmacological interventions were included.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two authors. The methodological quality of trials was evaluated using the components of randomisation, allocation concealment, double blinding, and inclusion of randomised participants.

MAIN RESULTS

Seventy-five randomised trials, involving 7957 participants with irritable bowel syndrome, met the inclusion criteria. The methodological quality of three double-blind, placebo-controlled trials was high, but the quality of remaining trials was generally low. Seventy-one different herbal medicines were tested in the included trials, in which herbal medicines were compared with placebo or conventional pharmacologic therapy. Herbal medicines were also combined with conventional therapy and compared to conventional therapy alone.Compared with placebo, a Standard Chinese herbal formula, individualised Chinese herbal medicine, STW 5 and STW 5-II, Tibetan herbal medicine Padma Lax, traditional Chinese formula Tongxie Yaofang, and Ayurvedic preparation showed significantly improvement of global symptoms. Compared with conventional therapy in 65 trials testing 51 different herbal medicines, 22 herbal medicines demonstrated a statistically significant benefit for symptom improvement, and 29 herbal medicines were not significantly different than conventional therapy. In nine trials that evaluated herbal medicine combined with conventional therapy, six tested herbal preparations showed additional benefit from the combination therapy compared with conventional monotherapy. No serious adverse events from the herbal medicines were reported.

AUTHORS' CONCLUSIONS

Some herbal medicines may improve the symptoms of irritable bowel syndrome. However, positive findings from less rigorous trials should be interpreted with caution due to inadequate methodology, small sample sizes, and lack of confirming data. Some herbal medicines deserve further examination in high-quality trials.

Application of LC-ESI-MS-MS for detection of synthetic adulterants in herbal remedies

Adulteration of allegedly "natural herbal medicines" with undeclared synthetic drugs is a common and dangerous phenomenon of alternative medicine. The purpose of the study was to develop a procedure for detection of most common synthetic adulterants in herbal remedies, using high-pressure liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS-MS). Eighty drugs belonging to various pharmacological classes were included in the study. For most drugs two transitions were monitored, using protonated or deprotonated molecules as precursor ions. The drugs were isolated from herbal remedies using simple methanol extraction. Chromatographic separation was done in gradient of acetonitrile-10 mM ammonium formate buffer (pH 3.0). Drugs tested were grouped in suites, comprising analgesic drugs, antibiotics, antidiabetic drugs, antiepileptic drugs, aphrodisiacs, hormones and anabolic drugs, psychotropic drugs, and weight reducing compounds. These suites were used according to the declared benefits of examined preparations. Limits of detection ranged from 5 pg to 1 ng per injected sample. Drug-free herbal remedy spiked with eight various pharmaceuticals occurring in adulterated herbal preparations was used for internal proficiency testing. The recoveries of spiked drugs ranged from 63 to 100%. The procedure was applied in everyday casework. Several undeclared drugs were identified in "herbal" remedies, like e.g. sildenafil, tadalafil, testosterone, or glibenclamide. Pharmacological properties of detected drugs always corresponded with the claims of the "natural" remedies. The method presents a valuable extension of standard GC-MS screening used for this purpose.

Simultaneous determination of synthetic phosphodiesterase-5 inhibitors found in a dietary supplement and pre-mixed bulk powders for dietary supplements using high-performance liquid chromatography with diode array detection and liquid chromatography-electrospray ionization tandem mass spectrometry

A high-performance liquid chromatography-diode array detection (HPLC-DAD) method and a liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) method were developed to screen for the presence of synthetic phosphodiesterase-5 (PDE-5) inhibitors and their analogues, namely sildenafil, vardenafil, tadalafil, homosildenafil, acetildenafil and hydroxyhomosildenafil. The methods were applied to pre-market samples submitted to the Health Sciences Authority of Singapore (HSA) for testing. One sample was in the form of capsules while six other samples were pre-mixed bulk powder samples for dietary supplements to be repackaged or formulated into the final dosage forms (usually capsules). Identification of PDE-5 inhibitors and their analogues was achieved by comparing individual peak retention times, UV spectra and mass spectra with those of reference standards. The seven samples were found to contain at least one of the following compounds: sildenafil, vardenafil, hydroxyhomosildenafil, homosildenafil and acetildenafil. The five compounds were simultaneously determined by LC-ESI-MS/MS in multiple reactions monitoring (MRM) scan mode. The method has been validated for accuracy, precision, linearity and sensitivity.

Adulteration of South African traditional herbal remedies

Traditional herbal remedies are used as alternative medicine by a large proportion of people worldwide. Herbals are generally perceived as safe, harmless, and free from side effects, but there have been reports of adulteration of Asian herbal remedies with Western pharmaceuticals, a practice that has not hitherto been observed in Africa. The authors present 2 cases from South Africa in which herbal remedies, consumed by patients admitted to hospital, were found to be adulterated with commercially available Western medicines. The adulterants were identified using high-performance liquid chromatography with a photodiode array detector and gas chromatography-mass spectrometry. The authors alert clinicians to the fact that adulteration of herbal remedies may become more common and should be considered, especially in cases where the symptoms are confusing in light of the history.

NATURAL HEALTH PRODUCTS AND DRUG DISPOSITION

Botanicals such as herbal products (HPs) and nutraceuticals (NCs) are often regarded as low risk because of their long history of human use. Anecdotal and literature reports of adverse drug events (ADEs) and clinical studies with HPs are increasing, but many of the reports are incomplete and contradictory. These reports need to identify confounding factors and explain contradictory findings if they are to help health care professionals or patients understand what risks are involved. HPs are complex botanicals, not single-active ingredient (SAI) products. Studies can be confounded by different manufacturing processes and formulations, including cosmetics and food supplements; environment; chemotypes; misidentification or adulteration; and factors associated with the patient or user population such as use, total drug load, and genetics. Future studies need to be conducted with characterized product that includes all commercially available related products. Clinical trials should be relevant to the user population and take into account the confounding factors that may influence the interpretation of the findings.

Risks of herbal medicinal products

PURPOSE

Herbal medicinal products (HMPs) are again highly popular. Their current popularity renders the assessment of their safety an urgent necessity.

METHOD

Narrative review using examples only.

RESULTS

Constituents of HMPs can be toxic and numerous examples of liver, kidney or other organ damage are on record. All HMPs contain a range of pharmacologically active constituents, and users of HMPs often combine HMPs with prescribed drugs. Thus herb-drug interactions are a real possibility. In most countries, HMPs are not submitted to stringent regulation and control. Thus unreliable quality can be a problem. In particular, this poses a risk when HMPs are contaminated (e.g. with heavy metals) or adulterated (e.g. with prescription drugs). The medical literature holds numerous examples for all of these scenarios and some are used in this article to illustrate the above points. As this area is grossly under-researched, it is rarely possible to define the size of the problem.

CONCLUSIONS

It is concluded that the widespread notion of HMPs being inherently safe is naive at best and dangerous at worst. More research is required to minimise the risk HMPs may pose to consumers' health.

Regulatory control of Chinese Proprietary Medicines in Singapore

In Singapore, there has been a growing public interest in traditional Chinese medicine (TCM), which plays an important role in the healthcare system. With effect from 1 September 1999, the control on Chinese Proprietary Medicines (CPM) was implemented in three phases over a span of 3 years. Under the CPM regulatory framework, CPM importers, wholesalers, manufacturers and re-packers must be licensed and CPM products assessed and listed by the health authority before they are allowed for sale. Product assessment is based on the criteria of safety and quality which include limits of toxic heavy metals and microbial contents. During the 3-year CPM listing exercise, irregularities were detected, including intrinsic toxicity, adulteration, substitution, contamination, misidentification, non-traditional and/or inappropriate usage, incorrect preparation, inappropriate labelling, exaggerated claims and/or advertising. The full implementation of CPM control by September 2001 saw the listing of 7943 CPM products and brought about an improvement in the quality and safety of CPM in Singapore as well as the removal of sub-standard, fake/imitation and adulterated products. The standards of practices by local CPM dealers have also been raised. These improvements have, in turn, increased the level of public confidence in CPM products in Singapore.