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Dubreil E, Darney K, Delignette-Muller ML, Barranger A, Huet S, Hogeveen K, Léger T, Fessard V, Hégarat LL. Modeling HepaRG metabolome responses to pyrrolizidine alkaloid exposure for insight into points of departure and modes of action. JOURNAL OF HAZARDOUS MATERIALS 2024; 474:134721. [PMID: 38843629 DOI: 10.1016/j.jhazmat.2024.134721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 05/12/2024] [Accepted: 05/22/2024] [Indexed: 06/26/2024]
Abstract
The new challenges in toxicology demand novel and innovative in vitro approaches for deriving points of departure (PODs) and determining the mode of action (MOA) of chemicals. Therefore, the aim of this original study was to couple in vitro studies with untargeted metabolomics to model the concentration-response of extra- and intracellular metabolome data on human HepaRG cells treated for 48 h with three pyrrolizidine alkaloids (PAs): heliotrine, retrorsine and lasiocarpine. Modeling revealed that the three PAs induced various monotonic and, importantly, biphasic curves of metabolite content. Based on unannotated metabolites, the endometabolome was more sensitive than the exometabolome in terms of metabolomic effects, and benchmark concentrations (BMCs) confirmed that lasiocarpine was the most hepatotoxic PA. Regarding its MOA, impairment of lipid metabolism was highlighted at a very low BMC (first quartile, 0.003 µM). Moreover, results confirmed that lasiocarpine targets bile acids, as well as amino acid and steroid metabolisms. Analysis of the endometabolome, based on coupling concentration-response and PODs, gave encouraging results for ranking toxins according to their hepatotoxic effects. Therefore, this novel approach is a promising tool for next-generation risk assessment, readily applicable to a broad range of compounds and toxic endpoints.
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Affiliation(s)
- Estelle Dubreil
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Toxicology of Contaminants Unit, 10 B rue Claude Bourgelat, 35306 Fougères, France.
| | - Keyvin Darney
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Risk Assessment Department, 14 Rue Pierre et Marie Curie, 94701 Maisons-Alfort, France
| | - Marie-Laure Delignette-Muller
- University of Lyon 1, CNRS, VetAgro Sup, UMR 5558, Laboratoire de Biométrie et Biologie Evolutive, 69622 Villeurbanne, France
| | - Audrey Barranger
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Toxicology of Contaminants Unit, 10 B rue Claude Bourgelat, 35306 Fougères, France
| | - Sylvie Huet
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Toxicology of Contaminants Unit, 10 B rue Claude Bourgelat, 35306 Fougères, France
| | - Kevin Hogeveen
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Toxicology of Contaminants Unit, 10 B rue Claude Bourgelat, 35306 Fougères, France
| | - Thibaut Léger
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Toxicology of Contaminants Unit, 10 B rue Claude Bourgelat, 35306 Fougères, France
| | - Valérie Fessard
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Toxicology of Contaminants Unit, 10 B rue Claude Bourgelat, 35306 Fougères, France
| | - Ludovic Le Hégarat
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Fougères Laboratory, Toxicology of Contaminants Unit, 10 B rue Claude Bourgelat, 35306 Fougères, France
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Letsyo E, Madilo FK, Effah-Manu L. Pyrrolizidine alkaloid contamination of food in Africa: A review of current trends and implications. Heliyon 2024; 10:e24055. [PMID: 38230234 PMCID: PMC10789634 DOI: 10.1016/j.heliyon.2024.e24055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 12/13/2023] [Accepted: 01/03/2024] [Indexed: 01/18/2024] Open
Abstract
Pyrrolizidine alkaloids (PAs) contamination of foodstuffs has become a topical issue in recent years on account of its potential hepatotoxicity to consumers. This review therefore highlights human exposure to PAs across Africa, focusing on their occurrence, current trends of food contamination, and their associated health implications. A comprehensive search of peer-scientific literature and relevant databases, PubMed, Google Scholar, Science Direct, Web of Science and Scopus, was conducted from 2001 to 2023 focusing mainly on foodstuffs, including grains, herbs, teas, honey, and livestock products. The findings revealed that PA contamination is a prevalent issue in several African countries, with the primary sources of contamination attributed to the consumption of honey and the use of PA plants as herbs in food preparations. Additionally, poor farming practices have been found to influence the presence and levels of PAs in foodstuffs. To mitigate PA contamination in food and safeguarding public health across the continent, several strategies are proposed, including the implementation of stringent regulatory and quality control measures, adoption of Good Agricultural Practices, and public awareness campaigns to educate producers, consumers and beekeepers about the risks associated with PA-contaminated food products.
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Affiliation(s)
- Emmanuel Letsyo
- Department of Food Science and Technology, Faculty of Applied Sciences and Technology, Ho Technical University, P.O Box HP 217, Ho, Ghana
| | - Felix Kwashie Madilo
- Department of Food Science and Technology, Faculty of Applied Sciences and Technology, Ho Technical University, P.O Box HP 217, Ho, Ghana
| | - Liticia Effah-Manu
- Department of Food Science and Technology, Faculty of Applied Sciences and Technology, Ho Technical University, P.O Box HP 217, Ho, Ghana
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3
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Eckert E, Lepper H, Hintzsche H. Risk assessment of short-term intake of pyrrolizidine alkaloids in food: derivation of an acute reference dose. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2023; 40:588-596. [PMID: 36794362 DOI: 10.1080/19440049.2023.2178828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Pyrrolizidine alkaloids (PA) are phytochemicals that are known to act as human hepatotoxins and are also considered to be genotoxic carcinogens. Several plant-derived foods are frequently contaminated with PA, like teas and herbal infusions, spices and herbs or certain food supplements. With respect to the chronic toxicity of PA, the carcinogenic potential of PA is generally regarded as the critical toxicological effect. The risk assessment of the short-term toxicity of PA, however, is internationally less consistent. The characteristic pathological syndrome of acute PA toxicity is hepatic veno-occlusive disease. High PA exposure levels may lead to liver failure and even death as documented by several case reports. In the present report, we suggest a risk assessment approach for the derivation of an acute reference dose (ARfD) for PA of 1 µg/kg body weight per day based on a sub-acute animal toxicity study in rats after oral PA administration. The derived ARfD value is further supported by several case reports describing acute human poisoning following accidental PA intake. The here derived ARfD value may be used for PA risk assessment in cases where the short-term toxicity of PA is of interest in addition to the assessment of the long-term risks.
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Affiliation(s)
- Elisabeth Eckert
- Department of Risk Assessment, Bavarian Health and Food Safety Authority, Erlangen, Germany.,Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Hans Lepper
- Department of Risk Assessment, Bavarian Health and Food Safety Authority, Erlangen, Germany
| | - Henning Hintzsche
- Department of Risk Assessment, Bavarian Health and Food Safety Authority, Erlangen, Germany.,Department of Food Safety, Institute of Food and Nutritional Sciences, University of Bonn, Bonn, Germany
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4
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Schrenk D, Fahrer J, Allemang A, Fu P, Lin G, Mahony C, Mulder PPJ, Peijnenburg A, Pfuhler S, Rietjens IMCM, Sachse B, Steinhoff B, These A, Troutman J, Wiesner J. Novel Insights into Pyrrolizidine Alkaloid Toxicity and Implications for Risk Assessment: Occurrence, Genotoxicity, Toxicokinetics, Risk Assessment-A Workshop Report. PLANTA MEDICA 2022; 88:98-117. [PMID: 34715696 DOI: 10.1055/a-1646-3618] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This paper reports on the major contributions and results of the 2nd International Workshop of Pyrrolizidine Alkaloids held in September 2020 in Kaiserslautern, Germany. Pyrrolizidine alkaloids are among the most relevant plant toxins contaminating food, feed, and medicinal products of plant origin. Hundreds of PA congeners with widespread occurrence are known, and thousands of plants are assumed to contain PAs. Due to certain PAs' pronounced liver toxicity and carcinogenicity, their occurrence in food, feed, and phytomedicines has raised serious human health concerns. This is particularly true for herbal teas, certain food supplements, honey, and certain phytomedicinal drugs. Due to the limited availability of animal data, broader use of in vitro data appears warranted to improve the risk assessment of a large number of relevant, 1,2-unsaturated PAs. This is true, for example, for the derivation of both toxicokinetic and toxicodynamic data. These efforts aim to understand better the modes of action, uptake, metabolism, elimination, toxicity, and genotoxicity of PAs to enable a detailed dose-response analysis and ultimately quantify differing toxic potencies between relevant PAs. Accordingly, risk-limiting measures comprising production, marketing, and regulation of food, feed, and medicinal products are discussed.
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Affiliation(s)
- Dieter Schrenk
- Food Chemistry and Toxicology, Technical University of Kaiserslautern, Kaiserslautern, Germany
| | - Jörg Fahrer
- Food Chemistry and Toxicology, Technical University of Kaiserslautern, Kaiserslautern, Germany
| | | | - Peter Fu
- National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR, USA
| | - Ge Lin
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR
| | - Catherine Mahony
- Procter & Gamble, Technical Centres Limited, Weybridge, Surrey, United Kingdom
| | - Patrick P J Mulder
- Wageningen Food Safety Research, Wageningen University & Research, Wageningen, the Netherlands
| | - Ad Peijnenburg
- Wageningen Food Safety Research, Wageningen University & Research, Wageningen, the Netherlands
| | | | | | - Benjamin Sachse
- German Federal Institute of Risk Assessment (BfR), Berlin, Germany
| | | | - Anja These
- German Federal Institute of Risk Assessment (BfR), Berlin, Germany
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Rutz L, Gao L, Küpper JH, Schrenk D. Structure-dependent genotoxic potencies of selected pyrrolizidine alkaloids in metabolically competent HepG2 cells. Arch Toxicol 2020; 94:4159-4172. [PMID: 32910235 PMCID: PMC7655576 DOI: 10.1007/s00204-020-02895-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 08/27/2020] [Indexed: 11/23/2022]
Abstract
1,2-unsaturated pyrrolizidine alkaloids (PAs) are natural plant constituents comprising more than 600 different structures. A major source of human exposure is thought to be cross-contamination of food, feed and phytomedicines with PA plants. In humans, laboratory and farm animals, certain PAs exert pronounced liver toxicity and can induce malignant liver tumors in rodents. Here, we investigated the cytotoxicity and genotoxicity of eleven PAs belonging to different structural classes. Although all PAs were negative in the fluctuation Ames test in Salmonella, they were cytotoxic and induced micronuclei in human HepG2 hepatoblastoma cells over-expressing human cytochrome P450 3A4. Lasiocarpine and cyclic diesters except monocrotaline were the most potent congeners both in cytotoxicity and micronucleus assays with concentrations below 3 μM inducing a doubling in micronuclei counts. Other open di-esters and all monoesters exhibited weaker or much weaker geno- and cytotoxicity. The findings were in agreement with recently suggested interim Relative Potency (iREP) factors with the exceptions of europine and monocrotaline. A more detailed micronuclei analysis at low concentrations of lasiocarpine, retrorsine or senecionine indicated that pronounced hypolinearity of the concentration–response curves was evident for retrorsine and senecionine but not for lasiocarpine. Our findings show that the genotoxic and cytotoxic potencies of PAs in a human hepatic cell line vary in a structure-dependent manner. Both the low potency of monoesters and the shape of prototype concentration–response relationships warrant a substance- and structure-specific approach in the risk assessment of PAs.
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Affiliation(s)
- Lukas Rutz
- Food Chemistry and Toxicology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Lan Gao
- Food Chemistry and Toxicology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Jan-Heiner Küpper
- Institute of Biotechnology, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Dieter Schrenk
- Food Chemistry and Toxicology, University of Kaiserslautern, Kaiserslautern, Germany.
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López-González R, Gnecco D, Juárez JR, Orea ML, Gómez-Calvario V, Bernès S, Aparicio DM, Terán JL. Synthesis of (+)- and (−)-Geissman-Waiss lactone from chiral sulfonium salts. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.151697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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7
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Schrenk D, Gao L, Lin G, Mahony C, Mulder PP, Peijnenburg A, Pfuhler S, Rietjens IM, Rutz L, Steinhoff B, These A. Pyrrolizidine alkaloids in food and phytomedicine: Occurrence, exposure, toxicity, mechanisms, and risk assessment - A review. Food Chem Toxicol 2020; 136:111107. [DOI: 10.1016/j.fct.2019.111107] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Revised: 12/26/2019] [Accepted: 12/29/2019] [Indexed: 02/03/2023]
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Bandini TB, Siani AC, Spisso BF. A botanical census on pyrrolizidine alkaloid-producing species in Brazilian herbaria: data set for a potential health risk indication. RODRIGUÉSIA 2020. [DOI: 10.1590/2175-7860202071118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract This study accessed the informational potential of herbaria collections as a tool for establishing an indication of the distribution of species that produce pyrrolizidine alkaloids (PAs), which are considered natural toxins, in Brazil. A total of 55,480 registered exsiccates were recorded, comprising species belonging to 17 genera, including Ipomoea (33.2%) (Convolvulaceae), Crotalaria (23.8%) (Fabaceae), Eupatorium (16.4%), Senecio (13.4%), Erechtites (3.97%) (Asteraceae) and Pleurothallis (8.28%) (Orchidaceae). These records were more densely distributed in the herbaria of the southeastern (30%), southern (28%) and northeastern (24%) Brazilian states. PAs are toxic to animals in general and display high potential for contamination of human food-production chains. A qualitative relationship was evidenced when carrying out a simultaneous compilation of cases of livestock intoxicated by the ingestion of these species, evidencing risks associated with PA-contaminated foodstuffs such as cereals, meats, milks and honey. The botanical census carried out herein is aimed at supporting a prospective study on the health risk presented by PA-producing species while bringing about indicators for their distribution in Brazil. This previously unpublished approach highlights the value of multidisciplinary information incorporated into herbaria botanical collections, with possible impacts on public health.
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9
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Prinsloo G, Steffens F, Vervoort J, Rietjens IM. Risk assessment of herbal supplements containing ingredients that are genotoxic and carcinogenic. Crit Rev Toxicol 2019; 49:567-579. [DOI: 10.1080/10408444.2019.1686456] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Gerhard Prinsloo
- Division of Toxicology, Wageningen University, Wageningen, Netherlands
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Sciences, University of South Africa, Florida, Johannesburg, South Africa
| | - Francois Steffens
- Department of Consumer Science, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Jacques Vervoort
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Sciences, University of South Africa, Florida, Johannesburg, South Africa
- Laboratory of Biochemistry, Wageningen University, Wageningen, Netherlands
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10
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Parvez MK, Rishi V. Herb-Drug Interactions and Hepatotoxicity. Curr Drug Metab 2019; 20:275-282. [PMID: 30914020 DOI: 10.2174/1389200220666190325141422] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/02/2019] [Accepted: 03/11/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND In recent times, herbals or phytomedicines have become very popular due to their global acceptance as a complementary and alternative remedy. While modern drugs are commercially available only after laboratory validations, clinical trials, as well as approval from drug regulatory authorities, majority of the marketed herbal products lack such scientific evidence of efficacy and safety. This results in herb or herb-drug interaction induced unfavorable clinical outcomes without crucial documentation on their temporal relations and concomitant use. METHODS An online literature search for peer-reviewed articles was conducted on the PubMed, Europe PMC, Medline and Google Scholar portals, using the phrases: complementary & alternative medicine, traditional Chinese medicine, herb-drug interaction, mechanisms of herb-drug interaction, herb-induced toxicity, herbal hepatotoxicity and causality, traditional medicine, viral hepatitis, etc. Results The retrieved data showed that globally, patients are attracted to herbal remedies with the misconception that these are completely safe and therefore, use them simultaneously with prescription drugs. Notably, there exists a potential risk of herb-drug interactions leading to some adverse side effects, including hepatotoxicity. The toxicological effect of a drug or herb is due to the inhibition of drug metabolizing enzymes (e.g., cytochrome P450), including interactions with certain prescription drugs through various mechanisms. Several cases of hepatotoxicity due to use of herbals in viral hepatitis-related liver diseases have been recently reported. However, limited experimental data and clinical evidence on herbal pharmacokinetics hamper the evaluation and reporting of adverse reactions and the underlying mechanisms. CONCLUSION Herb-drug interaction related morbidity is thus an emerging serious public health issue with broad implications for clinicians, pharmaceutical industries and health authorities. Nonetheless, despite increasing recognition of herb-drug interaction, a standard system for interaction prediction and evaluation is still nonexistent. This review article discusses the herb-drug interactions related hepatotoxicity and underlying mechanisms, including drug metabolizing enzymes and their regulation.
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Affiliation(s)
- Mohammad K Parvez
- Department of Pharmacognosy, King Saud University College of Pharmacy, Riyadh 11451, Saudi Arabia
| | - Vikas Rishi
- National Agri-Food Biotechnology Institute, Mohali, Punjab 140306, India
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11
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He X, Xia Q, Wu Q, Tolleson WH, Lin G, Fu PP. Primary and secondary pyrrolic metabolites of pyrrolizidine alkaloids form DNA adducts in human A549 cells. Toxicol In Vitro 2018; 54:286-294. [PMID: 30366057 DOI: 10.1016/j.tiv.2018.10.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 09/14/2018] [Accepted: 10/19/2018] [Indexed: 10/28/2022]
Abstract
Humans and animals can be exposed to carcinogenic pyrrolizidine alkaloids (PAs) through consumption of plants commonly found in many parts of the world. Although the liver is the primary target organ for carcinogenic PAs, they have also induced lung tumors in rodents. Hepatic cytochrome P450 activity converts PAs into dehydro-PAs that can be hydrolyzed to dehydropyrrolizidine (DHP); these reactive pyrrolic metabolites can produce four characteristic DNA adducts associated with PA-induced liver tumor initiation in laboratory animals. We reported recently that these four DNA adducts are also formed when 7-glutathione-DHP (7-GS-DHP) or 7-cysteine-DHP is incubated with calf thymus DNA. Here we showed that the four characteristic DNA adducts were formed when human A549 brochoalveolar carcinoma cells were treated with three dehydro-PAs (dehydroriddelliine, dehydromonocrotaline, or dehydroretronecine) or with 7-GS-DHP or 7-cysteine-DHP. For comparison, two parent PAs (riddelliine and monocrotaline) and 7,9-di-glutathionine-DHP were studied. No DHP-DNA adducts were detected with these incubations, confirming that A549 lung carcinoma cells do not express cytochrome P450 enzymes required for metabolic activation of PAs. Our results show that primary and secondary pyrrolic metabolites of carcinogenic PAs produce characteristic DHP-containing DNA adducts in A549 lung cancer cells, suggesting that they are DNA reactive metabolites.
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Affiliation(s)
- Xiaobo He
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Qingsu Xia
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Qiangen Wu
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - William H Tolleson
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Ge Lin
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Peter P Fu
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA.
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Gottschalk C, Huckauf A, Dübecke A, Kaltner F, Zimmermann M, Rahaus I, Beuerle T. Uncertainties in the determination of pyrrolizidine alkaloid levels in naturally contaminated honeys and comparison of results obtained by different analytical approaches. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2018; 35:1366-1383. [DOI: 10.1080/19440049.2018.1468929] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Christoph Gottschalk
- Chair of Food Safety, Veterinary Faculty, Ludwig-Maximilians-University Munich (LMU), Oberschleissheim, Germany
| | - Aiko Huckauf
- Nature Conservation Foundation Schleswig-Holstein, Tansy Ragwort Competence Centre, Molfsee, Germany
| | - Arne Dübecke
- QSI – Quality Services International GmbH, Bremen, Germany
| | - Florian Kaltner
- Chair of Food Safety, Veterinary Faculty, Ludwig-Maximilians-University Munich (LMU), Oberschleissheim, Germany
| | - Matthias Zimmermann
- Chair of Food Safety, Veterinary Faculty, Ludwig-Maximilians-University Munich (LMU), Oberschleissheim, Germany
| | - Ines Rahaus
- Institut für Pharmazeutische Biologie, Technische Universität Braunschweig (TUB), Braunschweig, Germany
| | - Till Beuerle
- Institut für Pharmazeutische Biologie, Technische Universität Braunschweig (TUB), Braunschweig, Germany
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13
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Mulder PPJ, López P, Castellari M, Bodi D, Ronczka S, Preiss-Weigert A, These A. Occurrence of pyrrolizidine alkaloids in animal- and plant-derived food: results of a survey across Europe. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2017; 35:118-133. [PMID: 28942718 DOI: 10.1080/19440049.2017.1382726] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Pyrrolizidine alkaloids (PAs) are secondary metabolites of plant families such as Asteraceae or Boraginaceae and are suspected to be genotoxic carcinogens. Recent investigations revealed their frequent occurrence in honey and particularly in tea. To obtain a comprehensive overview of the PA content in animal- and plant-derived food from the European market, and to provide a basis for future risk analysis, a total of 1105 samples were collected in 2014 and 2015. These comprised milk and milk products, eggs, meat and meat products, (herbal) teas, and (herbal) food supplements collected in supermarkets, retail shops, and via the internet. PAs were detected in a large proportion of plant-derived foods: 91% of the (herbal) teas and 60% of the food supplements contained at least one individual PA. All types of (herbal) teas investigated were found to contain PAs, with a mean concentration of 460 µg kg-1 dry tea (corresponding to 6.13 µg L-1 in [herbal] tea infusion). The highest mean concentrations were found in rooibos tea (599 µg kg-1 dry tea, 7.99 µg L-1 tea infusion) and the lowest in camomile tea (274 µg kg-1 dry tea, 3.65 µg L-1 tea infusion). Occurrence of PAs in food supplements was found to be highly variable, but in comparable ranges as for (herbal) tea. The highest concentrations were present in supplements containing plant material from known PA-producing plants. In contrast, only 2% of the animal-derived products, in particular 6% of milk samples and 1% of egg samples, contained PAs. Determined levels in milk were relatively low, ranged between 0.05 and 0.17 µg L-1 and only trace amounts of 0.10-0.12 µg kg-1 were found in eggs. No PAs were detected in the other animal-derived products.
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Affiliation(s)
- Patrick P J Mulder
- a RIKILT Wageningen University & Research , Wageningen , The Netherlands
| | - Patricia López
- a RIKILT Wageningen University & Research , Wageningen , The Netherlands
| | - Massimo Castellari
- b Institute for Research and Technology in Food and Agriculture (IRTA) , Monells , Spain
| | - Dorina Bodi
- c Department of Safety in the Food Chain , Federal Institute for Risk Assessment , Berlin , Germany
| | - Stefan Ronczka
- c Department of Safety in the Food Chain , Federal Institute for Risk Assessment , Berlin , Germany
| | - Angelika Preiss-Weigert
- c Department of Safety in the Food Chain , Federal Institute for Risk Assessment , Berlin , Germany
| | - Anja These
- c Department of Safety in the Food Chain , Federal Institute for Risk Assessment , Berlin , Germany
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14
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Penetration of lycopsamine from a comfrey ointment through human epidermis. Regul Toxicol Pharmacol 2017; 83:1-4. [PMID: 27840092 DOI: 10.1016/j.yrtph.2016.11.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 11/03/2016] [Accepted: 11/08/2016] [Indexed: 11/22/2022]
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15
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Diaz JH. Poisoning by Herbs and Plants: Rapid Toxidromic Classification and Diagnosis. Wilderness Environ Med 2017; 27:136-52. [PMID: 26948561 DOI: 10.1016/j.wem.2015.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/28/2015] [Accepted: 11/15/2015] [Indexed: 02/05/2023]
Abstract
The American Association of Poison Control Centers has continued to report approximately 50,000 telephone calls or 8% of incoming calls annually related to plant exposures, mostly in children. Although the frequency of plant ingestions in children is related to the presence of popular species in households, adolescents may experiment with hallucinogenic plants; and trekkers and foragers may misidentify poisonous plants as edible. Since plant exposures have continued at a constant rate, the objectives of this review were (1) to review the epidemiology of plant poisonings; and (2) to propose a rapid toxidromic classification system for highly toxic plant ingestions for field use by first responders in comparison to current classification systems. Internet search engines were queried to identify and select peer-reviewed articles on plant poisonings using the key words in order to classify plant poisonings into four specific toxidromes: cardiotoxic, neurotoxic, cytotoxic, and gastrointestinal-hepatotoxic. A simple toxidromic classification system of plant poisonings may permit rapid diagnoses of highly toxic versus less toxic and nontoxic plant ingestions both in households and outdoors; direct earlier management of potentially serious poisonings; and reduce costly inpatient evaluations for inconsequential plant ingestions. The current textbook classification schemes for plant poisonings were complex in comparison to the rapid classification system; and were based on chemical nomenclatures and pharmacological effects, and not on clearly presenting toxidromes. Validation of the rapid toxidromic classification system as compared to existing chemical classification systems for plant poisonings will require future adoption and implementation of the toxidromic system by its intended users.
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Affiliation(s)
- James H Diaz
- Department of Environmental and Occupational Health Sciences, School of Public Health; Department of Anesthesiology/Critical Care, School of Medicine, Louisiana State University Health Sciences Center (LSUHSC) in New Orleans, New Orleans, LA.
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Interim relative potency factors for the toxicological risk assessment of pyrrolizidine alkaloids in food and herbal medicines. Toxicol Lett 2016; 263:44-57. [PMID: 27157086 DOI: 10.1016/j.toxlet.2016.05.002] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/29/2016] [Accepted: 05/02/2016] [Indexed: 11/21/2022]
Abstract
Pyrrolizidine alkaloids (PAs) are among the most potent natural toxins occurring in a broad spectrum of plant species from various families. Recently, findings of considerable contamination of teas/herbal infusions prepared from non-PA plants have been reported. These are obviously due to cross-contamination with minor amounts of PA plants and can affect both food and herbal medicines. Another source of human exposure is honey collected from PA plants. These findings illustrate the requirement for a comprehensive risk assessment of PAs, hampered by the enormous number of different PA congeners occurring in nature. Up to now, risk assessment is based on the carcinogenicity of certain PAs after chronic application to rats using the sum of detected PAs as dose metric. Because of the well-documented large structure-dependent differences between sub-groups of PA congeners with respect to their genotoxicity and (cyto)toxicity, however, this procedure is inadequate. Here we provide an overview of recent attempts to assess the risk of PA exposure and the available literature on the toxic effects and potencies of different congeners. Based on these considerations, we have derived interim Relative Potency (REP) factors for a number of abundant PAs suggesting a factor of 1.0 for cyclic di-esters and open-chain di-esters with 7S configuration, of 0.3 for mono-esters with 7S configuration, of 0.1 for open-chain di-esters with 7R configuration and of 0.01 for mono-esters with 7R configuration. For N-oxides we suggest to apply the REP factor of the corresponding PA. We are confident that the use of these values can provide a more scientific basis for PA risk assessment until a more detailed experimental analysis of the potencies of all relevant congeners can be carried out.
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Mulder PP, Sánchez PL, These A, Preiss‐Weigert A, Castellari M. Occurrence of Pyrrolizidine Alkaloids in food. ACTA ACUST UNITED AC 2015. [DOI: 10.2903/sp.efsa.2015.en-859] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
| | | | - Anja These
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | | | - Massimo Castellari
- Institute for Research and Technology in Food and Agriculture (IRTA), Monells, Spain
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Schulz M, Meins J, Diemert S, Zagermann-Muncke P, Goebel R, Schrenk D, Schubert-Zsilavecz M, Abdel-Tawab M. Detection of pyrrolizidine alkaloids in German licensed herbal medicinal teas. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2015; 22:648-656. [PMID: 26055130 DOI: 10.1016/j.phymed.2015.03.020] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 02/26/2015] [Accepted: 03/23/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND Because of the hepatotoxic, mutagenic, and cancerogenic effects of pyrrolizidine alkaloids (PAs) the German Federal Institute for Risk Assessment (BfR) recommends not to exceed a daily PA intake of 0.007 µg/kg body weight (0.42 µg/60 kg adult). In a recent study conducted by the BfR, up to 5647 µg PA/kg dried herbal material were detected in tea products marketed as food. PURPOSE The present study aimed at elucidating whether medicinal teas licensed or registered as medicinal products contain PAs as well. STUDY DESIGN One hundred sixty-nine different commercially available medicinal teas, i.e. 19 nettle (Urtica dioica L.), 12 fennel (Foeniculum vulgare Mill.), 14 chamomile (Matricaria recutita L.), 11 melissa (Melissa officinalis L.) and 4 peppermint (Mentha piperita L.) teas as well as 109 tea mixtures were analyzed for the presence of 23 commercially available PAs. METHOD LC/MS was used for the determination of the PAs RESULTS In general, the total PA contents ranging 0-5668 µg/kg. Thirty percent of the tested single-ingredient tea products and 56.9% of the tested medicinal tea mixtures were found to contain PA concentrations above the limit of quantification (LOQ) of 10 µg/kg. In 11 medicinal teas PA contents >300 µg/kg dry herb were determined thus exceeding the recommended limit for PA intake by BfR. In addition three products of the investigated tea mixtures revealed extremely high PA contents of 4227, 5137, and 5668 µg/kg. Generally, single-ingredient tea products contained much less or even no detectable amounts of PAs when compared to the tea mixtures. PAs in the range between 13 and 1080 µg/kg were also detected in five analyzed aqueous herbal infusions of the medicinal tea mixture products with the highest PA content. Two out of the five investigated herbal infusions exceeded the recommended BfR limit for PA intake. CONCLUSION This study demonstrates clearly that also medicinal teas licensed as medicinal products may partly contain high amounts of PAs exceeding current recommendations. For that reason manufacturers are advised to carry out more rigorous quality control tests devoted to the detection of PAs. This is very important to minimize PAs in medicinal teas accounting for possible additional exposure of the consumer to PAs from other food sources (e.g. honey).
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Affiliation(s)
- M Schulz
- Drug Commission of German Pharmacists (AMK), Jaegerstrasse 49/50, 10117 Berlin, Germany
| | - J Meins
- Central Laboratory of German Pharmacists, Carl-Mannich-Strasse 20, 65760 Eschborn, Germany
| | - S Diemert
- Drug Commission of German Pharmacists (AMK), Jaegerstrasse 49/50, 10117 Berlin, Germany
| | - P Zagermann-Muncke
- Drug Commission of German Pharmacists (AMK), Jaegerstrasse 49/50, 10117 Berlin, Germany
| | - R Goebel
- Drug Commission of German Pharmacists (AMK), Jaegerstrasse 49/50, 10117 Berlin, Germany
| | - D Schrenk
- Department of Food Chemistry and Toxicology, Technische Universität Kaiserslautern, Erwin-Schrödinger-Strasse, 67663 Kaiserslautern, Germany
| | - M Schubert-Zsilavecz
- Central Laboratory of German Pharmacists, Carl-Mannich-Strasse 20, 65760 Eschborn, Germany; Department of Pharmaceutical Chemistry, Goethe-University Frankfurt, Max-von-Laue Strasse 9, 60438 Frankfurt am Main, Germany
| | - M Abdel-Tawab
- Central Laboratory of German Pharmacists, Carl-Mannich-Strasse 20, 65760 Eschborn, Germany.
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Griffin CT, Gosetto F, Danaher M, Sabatini S, Furey A. Investigation of targeted pyrrolizidine alkaloids in traditional Chinese medicines and selected herbal teas sourced in Ireland using LC-ESI-MS/MS. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2014; 31:940-61. [PMID: 24645695 DOI: 10.1080/19440049.2014.900193] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Publications linking hepatotoxicity to the use of herbal preparations are escalating. Herbal teas, traditional Chinese medicines (TCMs) and dietary supplements have been shown to contain pyrrolizidine alkaloids (PAs). Acute PA toxicosis of the liver can result in sinusoidal-obstruction syndrome, also known as veno-occlusive disease (VOD). This paper describes a sensitive and robust method for the detection of targeted PAs and their N-oxides (PANOs) in herbal products (selected herbal teas and TCMs) sourced within Ireland. The sample preparation includes a simple acidic extraction with clean-up via solid-phase extraction (SPE). Sample extracts were accurately analysed by using LC-ESI-MS/MS applying for the first time a pentafluorophenyl (PFP) core-shell column to the chromatographic separation of PAs and PANOs. The method was validated for selectivity, taking into consideration matrix effects, specificity, linearity, precision and trueness. Limits of detection (LOD) and limits of quantitation (LOQ) were quantified for all PAs and PANOs ranging from 0.4 to 1.9 µg kg⁻¹ and from 1.3 to 6.3 µg kg⁻¹, respectively. In this study 10 PAs and four PANOs were targeted because they are commercially available as reference standards. Therefore, this study can only report the levels of these PAs and PANOs analysed in the herbal teas and TCMs. The results reported represent the minimum levels of PAs and PANOs present in the samples analysed; commercially available herbal teas (n = 18) and TCMs (n = 54). A total of 50% herbal teas and 78% Chinese medicines tested positive for one or more PAs and/or PANOs included within this study, ranging from 10 to 1733 and from 13 to 3668 µg kg⁻¹, respectively.
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Affiliation(s)
- Caroline T Griffin
- a Department of Chemistry, Cork Institute of Technology (CIT) , Mass Spectrometry Research Centre (MSRC) and Team Elucidate Research Groups , Cork , Ireland
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Abstract
Hepatic sinusoidal obstruction syndrome (HSOS), characterized by hepatomegaly, ascites and hyperbilirubinemia, is caused by toxic injury to hepatic sinusoidal endothelial cells. One major etiology of HSOS in China is the intake of products containing pyrrolizidine alkaloids (PA) such as Tusanqi. The manifestations of patients with HSOS are usually non-specific, presenting with abnormal liver function and portal hypertension. Diagnosis of the disease depends mostly on liver histopathology when clinical and imaging data are not sufficient. A history of Tusanqi intake is mostly important for the diagnosis. Due to a lack of effective, evidence-based treatments for HSOS, avoiding the mistaken use of PA-containing products including Tusanqi is important for the prevention of HSOS.
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Affiliation(s)
- Ji Yao Wang
- Department of Gastroenterology, Zhongshan Hospital and Center of Evidence-Based Medicine, Fudan University, Shanghai, China
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Brambilla M, Davies SG, Fletcher AM, Thomson JE. Asymmetric and enantiospecific syntheses of 1-hydroxymethyl pyrrolizidine alkaloids. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.tetasy.2014.02.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Kim EJY, Chen Y, Huang JQ, Li KM, Razmovski-Naumovski V, Poon J, Chan K, Roufogalis BD, McLachlan AJ, Mo SL, Yang D, Yao M, Liu Z, Liu J, Li GQ. Evidence-based toxicity evaluation and scheduling of Chinese herbal medicines. JOURNAL OF ETHNOPHARMACOLOGY 2013; 146:40-61. [PMID: 23286904 DOI: 10.1016/j.jep.2012.12.027] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 12/19/2012] [Accepted: 12/19/2012] [Indexed: 05/19/2023]
Abstract
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.
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Affiliation(s)
- Ellie J Y Kim
- Faculty of Pharmacy, The University of Sydney, Sydney, NSW 2006, Australia
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Abstract
The One Health concept promotes collaboration among veterinarians, physicians, scientists, and other professions to promote human, animal, and ecosystem health. One Health illustrates the interconnectedness and interdependence of human, animal, and ecosystem health. This concept has traditionally focused on zoonoses that are infectious diseases, not on chemical- or poison-related illnesses in animals and their relationship to the detection and prevention of human illness. The purpose of this article is to describe key experiences of scientists in the Health Studies Branch within the National Center for Environmental of Health of the Centers for Disease Control and Prevention in which the study of animal illness facilitated a public health investigation into an outbreak of chemical-associated human disease. The experiences highlight how utilizing the One Health approach may improve chemical-associated outbreak investigations and facilitate appropriate intervention strategies. An appropriate One Health approach in toxicology and environmental health in outbreak settings should include consideration of the common environments and food sources shared by humans and animals and consideration of the potential for contaminated animal products as food sources in human exposures.
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Affiliation(s)
- Danielle E Buttke
- National Center for Environmental Health, Division of Environmental Hazards and Health Effects, Centers for Disease Control and Prevention, Chamblee, GA 30341, USA.
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Boppré M. The ecological context of pyrrolizidine alkaloids in food, feed and forage: an overview. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2011; 28:260-81. [DOI: 10.1080/19440049.2011.555085] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Gulumian M. The Perception and Practice of Toxicology in South Africa. Chem Res Toxicol 2008; 22:3-5. [DOI: 10.1021/tx800387j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mary Gulumian
- National Institute for Occupational Health andDepartment of Haematology and Molecular MedicineFaculty of Health SciencesUniversity of the WitwatersrandP.O. Box 4788Johannesburg 2000, South AfricaTel: E-mail:
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Kleiman R, Rentz ED, Teshale E, Thompson N, Schurz-Rogers H. Update on research and activities at the Centers for Disease Control and Prevention, and the agency for toxic substances and disease registry. J Med Toxicol 2008; 4:197-200. [PMID: 18821495 DOI: 10.1007/bf03161201] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Richard Kleiman
- Division of Toxicology and Environmental Medicine, Agency for Toxic Substances and Disease Registry (ATSDR)
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Dieter RK, Chen N, Watson RT. Copper mediated scalemic organolithium reagents in alkaloid syntheses. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.01.094] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Batey RG, Salmond SJ, Bensoussan A. Complementary and alternative medicine in the treatment of chronic liver disease. Curr Gastroenterol Rep 2005; 7:63-70. [PMID: 15701301 DOI: 10.1007/s11894-005-0068-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
Interest in and use of complementary and alternative medicines (CAM) in the treatment of chronic liver diseases has increased in the past decade. However, this has not been supported by a significant increase in sound clinical research evidence for their efficacy. The research literature is growing, providing improved knowledge on population use of CAM, possible mechanisms of action of a large range of complementary and alternative medications, and possible specific indications for these agents in patients with liver disease. Although curative potential for CAM has not been documented consistently in any liver disorder, it is possible to identify anti-inflammatory activity and cytoprotective capacity for a number of agents from different branches of the world of CAM. Evidence grows for potential harm from an increasing number of compounds. Concurrently, clarity is increasing in relation to which specific constituents cause the harm and the mechanisms by which damage is produced.
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Affiliation(s)
- Robert G Batey
- Faculty of Health, University of Newcastle, Australia, PO Box 119, Wallsend NSW 2287, Australia.
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Scherber C, Crawley MJ, Porembski S. The effects of herbivory and competition on the invasive alien plant Senecio inaequidens (Asteraceae). DIVERS DISTRIB 2003. [DOI: 10.1046/j.1472-4642.2003.00049.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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