Determination and risk assessment of naturally occurring genotoxic and carcinogenic alkenylbenzenes in nutmeg‐based plant food supplements

A risk assessment of nutmeg‐based plant food supplements (PFS) containing different alkenylbenzenes was performed based on the alkenylbenzene levels quantified in a series of PFS collected via the online market. The estimated daily intake (EDI) of the alkenylbenzenes amounted to 0.3 to 312 μg kg⁻¹ body weight (bw) for individual alkenylbenzenes, to 1.5 to 631 μg kg⁻¹ bw when adding up the alkenylbenzene levels assuming equal potency, and to 0.4 to 295 μg kg⁻¹ bw when expressed in safrole equivalents using toxic equivalency factors (TEFs). The margin of exposure approach (MOE) was used to evaluate the potential risks. Independent of the method used for the intake estimate, the MOE values obtained were generally lower than 10000 indicating a priority for risk management. When taking into account that PFS may be used for shorter periods of time and using Haber's rule to correct for shorter than lifetime exposure it was shown that limiting exposure to only 1 or 2 weeks would result in MOE values that would be, with the presently determined levels of alkenylbenzenes and proposed uses of the PFS, of low priority for risk management (MOE > 10000). It is concluded that the results of the present paper reveal that nutmeg‐based PFS consumption following recommendations for daily intake especially for longer periods of time raise a concern. Copyright © 2017 John Wiley & Sons, Ltd.     

Risk assessment for pyrrolizidine alkaloids detected in (herbal) teas and plant food supplements

Pyrrolizidine alkaloids (PAs) are plant metabolites present in some botanical preparations, with especially 1,2-unsaturated PAs being of concern because they are genotoxic carcinogens. This study presents an overview of tumour data on PAs and points of departure (PODs) derived from them, corroborating that the BMDL₁₀ for lasiocarpine represents a conservative POD for risk assessment. A risk assessment using this BMDL₁₀ and mean levels of PAs reported in literature for (herbal) teas, indicates that consumption of one cup of tea a day would result in MOE values lower than 10 000 for several types of (herbal) teas, indicating a priority for risk management for these products A refined risk assessment using interim relative potency (REP) factors showed that based on the mean PA levels, 7(54%) of 13 types of (herbal) teas and 1 (14%) of 7 types of plant food supplements (PFS) resulted in MOE values lower than 10 000, indicating a priority for risk management also for these products in particular. This includes both preparations containing PA-producing and non-PA-producing plants. Our study provides insight in the current state-of-the art and limitations in the risk assessment of PA-containing food products, especially (herbal) teas and PFS, indicating that PAs in food presents a field of interest for current and future risk management.     

Safety concerns of herbal products and traditional Chinese herbal medicines: dehydropyrrolizidine alkaloids and aristolochic acid

In many countries, including the United States, herbal supplements, tisanes and vegetable products, including traditional Chinese medicines, are largely unregulated and their content is not registered, monitored or verified. Consequently, potent plant toxins including dehydropyrrolizidine alkaloids and other potential carcinogens can contaminate these products. As herbal and food supplement producers are left to their own means to determine the safety and purity of their products prior to marketing, disturbingly often good marketing practices currently in place are ignored and content is largely undocumented. Historical examples of poisoning and health issues relating to plant material containing dehydopyrrolizidine alkaloids and aristolochic acids were used as examples to demonstrate the risk and potential toxicity of herbal products, food supplements, or traditional medicines. More work is needed to educate consumers of the potential risk and require the industry to be more responsible to verify the content and insure the safety of their products. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.     

Risk assessment of dietary exposures to compounds that are genotoxic and carcinogenic--an overview

The process of risk assessment of dietary exposures to genotoxic carcinogens is summarised. Exposures to six genotoxic carcinogens in food (acrylamide, aflatoxin B(1), benzo(a)pyrene, dimethylnitrosamine, ethyl carbamate, PhIP) have been used to illustrate the process. The margin of exposure (MOE) approach is seen as a useful method to be used in the risk characterisation step of assessing exposures to genotoxic carcinogens. This approach combines information on animal potency and human exposure, and can be used to indicate levels of concern and also the ranking between various exposures to such agents. Both the T25 and the BMDL10 methods may be used as a reference point. Should a specific MOE value be developed as a cut-off between levels of concern and levels of low concern, the value using T25 data is proposed to be 2.5-times higher than using BMDL10 data. Linear low-dose extrapolation using either T25 or BMDL10, may also be applied. However, it should be understood that this approach should not be interpreted as giving a precise estimate of human risk. For exposures to mutagens in food lacking carcinogenicity data, it is proposed to apply the MOE approach to the lowest effective dose (LED) for in vivo genotoxicity.     

欧盟草药临床安全性和有效性评估指导原则介绍

欧盟（European Union,EU）于2016年7月发布了《在欧盟草药专论编写中评估公认的和传统的草药产品临床安全性和有效性的指导原则（第一次修订版）》。其中最值得注意的是,草药产品申请注册时可用文献资料替代试验资料,并且可根据文献资料科学性不同,获准不同的适应证。介绍该指导原则的主要内容,期望对我国的中药和植物药研究及其监管有所帮助。     

Risk assessment of botanicals and botanical preparations intended for use in food and food supplements: emerging issues

At present there is a growing interest for use of botanicals and botanical ingredients in medicines, for teas or in foods and in food supplements. In addition, a number of plant-derived food items form an integral part of regular human diets. Currently, there is an increasing awareness among safety experts and regulators of risks associated with the use of botanicals and botanical ingredients in food including food supplements. It is becoming clear that "natural" does not equal "safe" and that, in modern society, adverse health effects can occur as a result of (mis)use. With the growing awareness of these issues efforts to ensure safety of botanicals and botanical ingredients are also increasing. Several guidance documents on safety assessment of botanicals and botanical preparations to be used as ingredients in food and food supplements have been published, although, at present, relevant legislative frameworks and guidances for risk assessment are not established yet. Furthermore, when defining possible guidance documents for risk assessment of botanicals, several issues emerge that need to be developed beyond the present state-of-the-art. The present paper describes some of the issues to be considered and developed to a further extent to improve risk assessment of botanicals and botanical preparations, illustrated by examples based on some allylalkoxybenzenes. It is concluded that, for an improved and more accurate future risk assessment of botanicals, it is necessary to further develop and validate: (i) the use of the margin of exposure (MOE) concept for compounds that are both genotoxic and carcinogenic; (ii) new ways to quantify and incorporate matrix effects into risk assessment strategies; (iii) the use of analytical chemistry approaches, enabling complete chemical characterisation of complex mixtures. Defining new approaches in risk assessment would be in line with the inspiring attitude of the late Professor Robert Kroes, who, for example by supporting the threshold of toxicological concern (TTC) concept, was a pioneer for development and implementation of new paradigms in the field of risk assessment and food safety.     

Human health risk assessment of endosulfan: II. Dietary exposure assessment

The California Department of Pesticide Regulation (CDPR) and the United States Environmental Protection Agency (USEPA) performed dietary exposure assessments for endosulfan in 1998 and 2002, respectively. Results of the USEPA assessment showed an increased risk for the population sub-group “Children 1–6 years” (>100% of the Population Adjusted Dose [PAD]). USEPA then required registrants to satisfy database uncertainties by performing subchronic neurotoxicity and developmental neurotoxicity studies and, based on the results, USEPA decreased the Food Quality Protection Act (FQPA, 1996) Safety Factor from 10× to 1×. Additionally, several tolerances on commodities consumed in quantity by children were cancelled in 2006. CDPR re-evaluated the dietary risk initially performed in 1998 after review of these same studies. Based on a review of the revised USEPA tolerances, decreased usage, decreased consumption, cancellations, and prior health protective margins of exposure (MOEs > 100), CDPR determined that it was not necessary to redo the 1998 exposure assessment. In 2007, USEPA conducted a new human health risk assessment for endosulfan combining food + drinking water residues that characterized dietary risk as %PAD = ([Exposure ÷ PAD] × 100). For all relevant USEPA population sub-groups, the %PADs were < 100% (health protective benchmark).     

Risk metrics and cumulative risk assessment methodology for the FQPA

The Food Quality Protection Act (FQPA) of 1996 mandates that the U.S. Environmental Protection Agency consider both aggregate and cumulative risks. Aggregate assessments account for multiple sources and routes of exposure for a single chemical. Cumulative assessments combine exposures to two or more chemicals that share a common mechanism of toxicity. Probabilistic risk assessment methods are described for determining a population's distribution of the dose from exposure and the combination of that exposure characterization with appropriate toxicological information to form a risk assessment. An individual's dose from exposure is characterized as a set of chemical- and route-specific dose profiles over time. For each individual and each chemical and route, a margin of exposure (MOE) is calculated by dividing a toxicologically relevant benchmark dose (e.g., an ED(10)) by the individual's dose from exposure. The set of these MOEs for an individual is combined into the individual's Total MOE. The distribution of the Total MOEs in a population is compared to an Acceptable MOE. Advantages of the Total MOE approach over approaches based on reference doses are discussed. Some general comments on risk metrics are made, and some general guidance for cumulative risk assessments is provided.     

Origin of the TTC values for compounds that are genotoxic and/or carcinogenic and an approach for their re-evaluation

The threshold of toxicological concern (TTC) approach is a resource-effective de minimis method for the safety assessment of chemicals, based on distributional analysis of the results of a large number of toxicological studies. It is being increasingly used to screen and prioritize substances with low exposure for which there is little or no toxicological information. The first step in the approach is the identification of substances that may be DNA-reactive mutagens, to which the lowest TTC value is applied. This TTC value was based on the analysis of the cancer potency database and involved a number of assumptions that no longer reflect the state-of-the-science and some of which were not as transparent as they could have been. Hence, review and updating of the database is proposed, using inclusion and exclusion criteria reflecting current knowledge. A strategy for the selection of appropriate substances for TTC determination, based on consideration of weight of evidence for genotoxicity and carcinogenicity is outlined. Identification of substances that are carcinogenic by a DNA-reactive mutagenic mode of action and those that clearly act by a non-genotoxic mode of action will enable the protectiveness to be determined of both the TTC for DNA-reactive mutagenicity and that applied by default to substances that may be carcinogenic but are unlikely to be DNA-reactive mutagens (i.e. for Cramer class I–III compounds). Critical to the application of the TTC approach to substances that are likely to be DNA-reactive mutagens is the reliability of the software tools used to identify such compounds. Current methods for this task are reviewed and recommendations made for their application.     

Integration of mechanistic and pharmacokinetic information to derive oral reference dose and margin‐of‐exposure values for hexavalent chromium

The current US Environmental Protection Agency (EPA) reference dose (RfD) for oral exposure to chromium, 0.003 mg kg^?1 day^?1, is based on a no‐observable‐adverse‐effect‐level from a 1958 bioassay of rats exposed to ≤25 ppm hexavalent chromium [Cr(VI)] in drinking water. EPA characterizes the confidence in this RfD as “low.” A more recent cancer bioassay indicates that Cr(VI) in drinking water is carcinogenic to mice at ≥30 ppm. To assess whether the existing RfD is health protective, neoplastic and non‐neoplastic lesions from the 2 year cancer bioassay were modeled in a three‐step process. First, a rodent physiological‐based pharmacokinetic (PBPK) model was used to estimate internal dose metrics relevant to each lesion. Second, benchmark dose modeling was conducted on each lesion using the internal dose metrics. Third, a human PBPK model was used to estimate the daily mg kg^?1 dose that would produce the same internal dose metric in both normal and susceptible humans. Mechanistic research into the mode of action for Cr(VI)‐induced intestinal tumors in mice supports a threshold mechanism involving intestinal wounding and chronic regenerative hyperplasia. As such, an RfD was developed using incidence data for the precursor lesion diffuse epithelial hyperplasia. This RfD was compared to RfDs for other non‐cancer endpoints; all RfD values ranged 0.003–0.02 mg kg^?1 day^?1. The lowest of these values is identical to EPA's existing RfD value. Although the RfD value remains 0.003 mg kg^?1 day^?1, the confidence is greatly improved due to the use of a 2‐year bioassay, mechanistic data, PBPK models and benchmark dose modeling.     

Matrix-derived combination effect and risk assessment for estragole from basil-containing plant food supplements (PFS)

Basil-containing plant food supplements (PFS) can contain estragole which can be metabolised into a genotoxic and carcinogenic 1′-sulfoxymetabolite. This study describes the inhibition of sulfotransferase (SULT)-mediated bioactivation of estragole by compounds present in basil-containing PFS. Results reveal that PFS consisting of powdered basil material contain other compounds with considerable in vitro SULT-inhibiting activity, whereas the presence of such compounds in PFS consisting of basil essential oil was limited. The inhibitor in powdered basil PFS was identified as nevadensin. Physiologically based kinetic (PBK) modeling was performed to elucidate if the observed inhibitory effects can occur in vivo. Subsequently, risk assessment was performed using the Margin of Exposure (MOE) approach. Results suggest that the consequences of the in vivo matrix-derived combination effect are significant when estragole would be tested in rodent bioassays with nevadensin at ratios detected in PFS, thereby increasing MOE values. However, matrix-derived combination effects may be limited at lower dose levels, indicating that the importance of matrix-derived combination effects for risk assessment of individual compounds should be done on a case-by-case basis considering dose-dependent effects. Furthermore, this study illustrates how PBK modeling can be used in risk assessment of PFS, contributing to further reduction in the use of experimental animals.     

Risk assessment of substances that are both genotoxic and carcinogenic report of an International Conference organized by EFSA and WHO with support of ILSI Europe.

The European Food Safety Authority (EFSA) and the World Health Organization (WHO), with the support of the International Life Sciences Institute, European Branch (ILSI Europe), organized an international conference on 16-18 November 2005 to discuss how regulatory and advisory bodies evaluate the potential risks of the presence in food of substances that are both genotoxic and carcinogenic. The objectives of the conference were to discuss the possible approaches for risk assessment of such substances, how the approaches may be interpreted and whether they meet the needs of risk managers. ALARA (as low as reasonably achievable) provides advice based solely on hazard identification and does not take into account either potency or human exposure. The use of quantitative low-dose extrapolation of dose-response data from an animal bioassay raises numerous scientific uncertainties related to the selection of mathematical models and extrapolation down to levels of human exposure. There was consensus that the margin of exposure (MOE) was the preferred approach because it is based on the available animal dose-response data, without extrapolation, and on human exposures. The MOE can be used for prioritisation of risk management actions but the conference recognised that it is difficult to interpret it in terms of health risk.     

陕西省12种中药饮片微生物污染调查及风险评估

目的调查陕西省12种常见中药饮片的微生物污染状况,并评估其潜在风险。方法按照《中国药典》2015年版和《食品安全国家标准》方法对金银花等12种中药饮片进行需氧菌总数(TAMC)、霉菌和酵母菌总数(TYMC)、耐热菌数及控制菌检查。结果中药饮片TAMC>104 cfu·g~(-1)的为70%(84/120),TYMC>102 cfu·g~(-1)的为65%(78/120),耐热菌数>102 cfu·g~(-1)的为49.2%(59/120),预培养处理有助于耐胆盐革兰阴性菌的检出,为75.0%(90/120),大肠埃希菌的检出率为3.33%,铜绿假单胞菌的检出率为7.5%。结论中药饮片微生物污染情况比较严重,卫生质量亟待提高,应建立合理的微生物质量控制标准。     

Exposure Assessment of Multiple Mycotoxins and Cumulative Health Risk Assessment: A Biomonitoring-Based Study in the Yangtze River Delta,China

The extensive exposure to multiple mycotoxins has been demonstrated in many countries; however, realistic assessments of the risks related to cumulative exposure are limited. This biomonitoring study was conducted to investigate exposure to 23 mycotoxins/metabolites and their determinants in 227 adults (aged 20–88 years) in the Yangtze River Delta, China. Eight mycotoxins were detected in 110 urine samples, and multiple mycotoxins co-occurred in 51/227 (22.47%) of urine samples, with deoxynivalenol (DON), fumonisin B1 (FB1), and zearalenone (ZEN) being the most frequently occurring. For single mycotoxin risk assessment, FB1, ZEN, aflatoxin B1 (AFB1), and ochratoxin A (OTA) all showed potential adverse effects. However, for the 12 samples containing DON and ZEN, in which none had a hazard risk, the combination of both mycotoxins in two samples was considered to pose potential endocrine disrupting risks to humans by hazard index (HI) method. The combined margin of exposure (MOE_T) for AFB1 and FB1 could constitute a potential health concern, and AFB1 was the main contributor. Our approach provides a blueprint for evaluating the cumulative risks related to different types of mycotoxins and opens a new horizon for the accurate interpretation of epidemiological health outcomes related to multi-mycotoxin exposure.     

Risk assessment strategies for nanoscale and fine-sized titanium dioxide particles: Recognizing hazard and exposure issues

The basic tenets for assessing health risks posed by nanoparticles (NP) requires documentation of hazards and the corresponding exposures that may occur. Accordingly, this review describes the range and types of potential human exposures that may result from interactions with titanium dioxide (TiO₂) particles or NP – either in the occupational/workplace environment, or in consumer products, including food materials and cosmetics. Each of those applications has a predominant route of exposure. Very little is known about the human impact potential from environmental exposures to NP – thus this particular issue will not be discussed further. In the workplace or occupational setting inhalation exposure predominates. Experimental toxicity studies demonstrate low hazards in particle-exposed rats. Only at chronic overload exposures do rats develop forms of lung pathology. These findings are not supported by multiple epidemiology studies in heavily-exposed TiO₂ workers which demonstrate a lack of correlation between chronic particle exposures and adverse health outcomes including lung cancer and noncancerous chronic respiratory effects. Cosmetics and sunscreens represent the major application of dermal exposures to TiO₂ particles. Experimental dermal studies indicate a lack of penetration of particles beyond the epidermis with no consequent health risks. Oral exposures to ingested TiO₂ particles in food occur via passage through the gastrointestinal tract (GIT), with studies indicating negligible uptake of particles into the bloodstream of humans or rats with subsequent excretion through the feces. In addition, standardized guideline-mandated subchronic oral toxicity studies in rats demonstrate very low toxicity effects with NOAELs of >1000 mg/kg bw/day. Additional issues which are summarized in detail in this review are: 1) Methodologies for implementing the Nano Risk Framework – a process for ensuring the responsible development of products containing nanoscale materials; and 2) Safe-handling of nanomaterials in the laboratory.     

Risk assessment of local dermal effects and skin sensitisation under the EU Chemicals Regulation REACH: a proposal for a qualitative, exposure scenario specific, approach

Within the framework of REACH, an assessment regarding local dermal effects and skin sensitisation should be performed for substances. Quantitative hazard information for these effects is often not available. Furthermore, it is difficult to relate the way in which animals are exposed in dermal toxicity studies directly to dermal exposure in practice. In the absence of quantitative information, a qualitative assessment for dermal effects is the most reasonable option. The qualitative approach as proposed in the REACH guidance recommends only general risk management measures (RMM) for three categories with a low, moderate and high identified hazard, without specifying which RMM are needed for a specific exposure scenario. We propose to differentiate frequency of exposure based on differences in activities and to compare measured and estimated local skin exposure levels with rules of thumb for evaluation of control of risks per hazard category. For workers, specific RMM regimes are assigned to each combination of hazard category and process category (PROC). For consumers, a strategy in which RMM are arranged from product-integrated measures to the use of personal protective equipment (PPE) is presented. Our approach may be transferred into automated assessment tools like Chesar and CEFIC GES.     

Modernization of Chinese herbal compound and the high performance liquid chromatography tandem mass spectrometry (HPLC-MS)

Chinese herbal compound is playing an important role on curing human diseases.And it has been a trend that Chinese herbal compound is being used all over the world in 21 century.However,our Chinese herbal compound is facing serious challenge for the lack of canonical system of quality criterion for Chinese herbal compound so it has been a urgent problem to set up the quality control standards and reveal therapeutic basis of Chinese herbal compound.In order to give full play to the advantages of Chinese herbal compound,modern scientific and technological is used to research of Chinese herbal compound,especially the high performance liquid chromatography tandem mass spectrometry(HPLC-MS),because it is high sensitive,rapid,and obtain more information.It is very necessary that HPLC-MS is uesed to elucidate the effective components of basic substances of Chinese Herbal Compound,and endow traditional Chinese medicine with modern scientific connotation.     

The interaction potential of herbal medicinal products: a luminescence-based screening platform assessing effects on cytochrome P450 and its use with devil's claw (Harpagophyti radix) preparations

Objectives Potential interactions between herbal medicinal products and the cytochrome (CYP) P450 system are an important safety concern. We set out to develop a screening panel for assessing such interactions and use it to evaluate the interaction potential of devil's claw. Methods The panel consisted of luminescence‐based inhibition assays for CYP1A2, 2C9, 2C19, 2D6 and 3A4, and a reporter gene (luciferase) assay for pregnane X receptor (PXR) activation and CYP3A4 induction. Caftaric acid and chlorogenic acid, two compounds with strong fluorescence quenching properties, were used to demonstrate the assay's resistance to interference. We tested 10 commercial devil's claw preparations as well as harpagoside and harpagide, two important constituents of devil's claw. Key findings Five preparations were found to weakly inhibit CYP3A4 (IC50 124.2–327.6 µg/ml) and five were found to weakly activate PXR (EC50 10.21–169.3 µg/ml). Harpagoside and harpagide did not inhibit CYP3A4. In agreement with published data, bergamottin, a natural product known to interact with CYP3A4, was shown to inhibit CYP3A4 with an IC50 of 13.63 µm and activate PXR with an EC50 of 6.7 µm . Conclusions Devil's claw preparations are unlikely to have a clinically relevant effect on CYP function. The assay panel proved effective in screening devil's claw preparations, demonstrating its suitability for use with plant extracts. It showed superior sensitivity and resistance to interference.