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Lesné L, Desdoits-Lethimonier C, Hug E, Costet N, Raffenne L, Toupin M, Evrard B, Kugathas I, Lavoué V, Chalmel F, Jégou B, Mazaud-Guittot S. Antiepileptic drugs are endocrine disruptors for the human fetal testis ex vivo. Toxicol Sci 2023; 195:169-183. [PMID: 37505509 DOI: 10.1093/toxsci/kfad076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023] Open
Abstract
Valproic acid (VPA) has long been the most widely used antiepileptic drug (AED) for the treatment of epilepsy, bipolar psychiatric disorders, and migraine. However, long-term VPA treatment has several adverse effects on the male reproductive system notably on endocrine functions and/or spermatic parameters. In utero exposure of the fetus to VPA is well known to be associated with a higher risk of several congenital malformations including those of male reproductive organs. Subsequent generations of AEDs, such as carbamazepine (CARB) and lamotrigine (LAM), are considered safer and are currently recommended for women of child-bearing age with epilepsy. Because anomalies of the male genital tract mostly result from endocrine imbalance during fetal life, we hypothesized that AEDs could directly impair testis differentiation. We thus aimed at identifying and characterizing the effects of VPA, CARB, and LAM on the differentiation and function of the different testicular cell types, and at understanding the mechanisms underlying these effects. By using ex vivo culture of first-trimester human fetal testes, we show that VPA induces multiple endocrine disruptive effects, compared with the milder ones caused by CARB and LAM. AED also subtly altered the germ cell lineage in distinct manners. Transcriptomic analysis of VPA-induced alterations highlighted a very broad range of effects on the fetal testis. Overall, our results show that AEDs can behave as endocrine disruptors for the human fetal testis ex vivo. This is consistent with, and likely underlies, the VPA-induced male genital tract masculinization abnormalities observed in patients.
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Affiliation(s)
- Laurianne Lesné
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Christèle Desdoits-Lethimonier
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Elisa Hug
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Nathalie Costet
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Léo Raffenne
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Maryne Toupin
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Bertrand Evrard
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Indusha Kugathas
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Vincent Lavoué
- Univ Rennes, CHU Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Frédéric Chalmel
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
| | - Bernard Jégou
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
- EHESP-School of Public Health, 35043 Rennes, France
| | - Séverine Mazaud-Guittot
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail)-UMR_S 1085, 35000 Rennes, France
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Lotfata A, Moosazadeh M, Helbich M, Hoseini B. Socioeconomic and environmental determinants of asthma prevalence: a cross-sectional study at the U.S. County level using geographically weighted random forests. Int J Health Geogr 2023; 22:18. [PMID: 37563691 PMCID: PMC10413687 DOI: 10.1186/s12942-023-00343-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 08/04/2023] [Indexed: 08/12/2023] Open
Abstract
BACKGROUND Some studies have established associations between the prevalence of new-onset asthma and asthma exacerbation and socioeconomic and environmental determinants. However, research remains limited concerning the shape of these associations, the importance of the risk factors, and how these factors vary geographically. OBJECTIVE We aimed (1) to examine ecological associations between asthma prevalence and multiple socio-physical determinants in the United States; and (2) to assess geographic variations in their relative importance. METHODS Our study design is cross sectional based on county-level data for 2020 across the United States. We obtained self-reported asthma prevalence data of adults aged 18 years or older for each county. We applied conventional and geographically weighted random forest (GWRF) to investigate the associations between asthma prevalence and socioeconomic (e.g., poverty) and environmental determinants (e.g., air pollution and green space). To enhance the interpretability of the GWRF, we (1) assessed the shape of the associations through partial dependence plots, (2) ranked the determinants according to their global importance scores, and (3) mapped the local variable importance spatially. RESULTS Of the 3059 counties, the average asthma prevalence was 9.9 (standard deviation ± 0.99). The GWRF outperformed the conventional random forest. We found an indication, for example, that temperature was inversely associated with asthma prevalence, while poverty showed positive associations. The partial dependence plots showed that these associations had a non-linear shape. Ranking the socio-physical environmental factors concerning their global importance showed that smoking prevalence and depression prevalence were most relevant, while green space and limited language were of minor relevance. The local variable importance measures showed striking geographical differences. CONCLUSION Our findings strengthen the evidence that socio-physical environments play a role in explaining asthma prevalence, but their relevance seems to vary geographically. The results are vital for implementing future asthma prevention programs that should be tailor-made for specific areas.
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Affiliation(s)
- Aynaz Lotfata
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Mohammad Moosazadeh
- Integrated Engineering, Department of Environmental Science and Engineering, College of Engineering, KyungHee University, Yongin, 446-701, Republic of Korea
| | - Marco Helbich
- Department of Human Geography and Spatial Planning, Faculty of Geosciences, University Utrecht, Utrecht, The Netherlands
| | - Benyamin Hoseini
- Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
- Department of Medical Informatics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
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Park YJ, Pang WK, Ryu DY, Adegoke EO, Rahman MS, Pang MG. Bisphenol A exposure increases epididymal susceptibility to infection in mice. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111476. [PMID: 33091778 DOI: 10.1016/j.ecoenv.2020.111476] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 10/07/2020] [Accepted: 10/07/2020] [Indexed: 06/11/2023]
Abstract
Male fertility is linked with several well-orchestrated events including spermatogenesis, epididymal maturation, capacitation, the acrosome reaction, fertilization, and beyond. However, the detrimental effects of bisphenol A (BPA) on sperm maturation compared to spermatogenesis and sperm cells remain unclear. Therefore, this study was to investigate whether pubertal exposure to BPA induces male infertility via interruption of the immune response in the epididymis. CD-1 male mice (5 weeks old) were treated daily with vehicle (corn oil) and 50 mg BPA/kg-BW for 6 weeks by oral gavage. Following BPA exposure, we observed decreased intraepithelial projection of basal cells, indicative of changes to the luminal environment. We also observed decreased projection of macrophages and protrusion of apoptotic cells into the lumen induced by incomplete phagocytosis of apoptotic cells in the caput epididymis. Exposure to BPA also reduced the anti- and pro-inflammatory cytokines IL-10, IL-6, IFN-γ, and IL-7 in the epididymis, while the chemotaxis-associated cytokines CCL12, CCL17, CXCL16, and MCP-1 increased. This study suggests two possible mechanisms for BPA induction of male infertility. First, exposure to BPA may induce an imbalance of immune homeostasis by disrupting the ability of basal cells to perceive environmental changes. Second, exposure to BPA may lead to collapse of macrophage phagocytosis via downregulation of intraepithelial projection and inflammatory-related cytokines. In conclusion, the observed potential pathways can lead to autoimmune disorders such epididymitis and orchitis.
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Affiliation(s)
- Yoo-Jin Park
- Department of Animal Science & Technology and BET Research Institute, Chung-Ang University, Anseong, Gyeonggi-do 17546, Republic of Korea
| | - Won-Ki Pang
- Department of Animal Science & Technology and BET Research Institute, Chung-Ang University, Anseong, Gyeonggi-do 17546, Republic of Korea
| | - Do-Yeal Ryu
- Department of Animal Science & Technology and BET Research Institute, Chung-Ang University, Anseong, Gyeonggi-do 17546, Republic of Korea
| | - Elikanah Olusayo Adegoke
- Department of Animal Science & Technology and BET Research Institute, Chung-Ang University, Anseong, Gyeonggi-do 17546, Republic of Korea
| | - Md Saidur Rahman
- Department of Animal Science & Technology and BET Research Institute, Chung-Ang University, Anseong, Gyeonggi-do 17546, Republic of Korea
| | - Myung-Geol Pang
- Department of Animal Science & Technology and BET Research Institute, Chung-Ang University, Anseong, Gyeonggi-do 17546, Republic of Korea.
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Autrup H, Barile FA, Berry SC, Blaauboer BJ, Boobis A, Bolt H, Borgert CJ, Dekant W, Dietrich D, Domingo JL, Gori GB, Greim H, Hengstler J, Kacew S, Marquardt H, Pelkonen O, Savolainen K, Heslop-Harrison P, Vermeulen NP. Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity. How to evaluate the risk of the S-EDCs? Toxicol Lett 2020; 331:259-264. [PMID: 32360654 DOI: 10.1016/j.toxlet.2020.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 04/08/2020] [Indexed: 12/25/2022]
Affiliation(s)
- Herman Autrup
- Institute of Public Health, University of Aarhus, Aarhus, Denmark
| | - Frank A Barile
- College of Pharmacy and Health Sciences, St John's University, Queens, NY, USA
| | | | - Bas J Blaauboer
- Division of Toxicology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands
| | - Alan Boobis
- National Heart & Lung Institute, Imperial College, London, UK
| | - Herrmann Bolt
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), TU Dortmund, Dortmund, Germany
| | | | - Wolfgang Dekant
- Department of Toxicology, University of Wuerzburg, Wuerzburg, Germany
| | - Daniel Dietrich
- Human and Environmental Toxicology, University of Konstanz, Konstanz, Germany
| | - Jose L Domingo
- Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat 'Rovira i Virgili', Reus, Spain
| | | | - Helmut Greim
- Technical University of Munich, Hohenbachernstrasse 15-17, D-85350, Freising, Weihenstephan, Germany.
| | - Jan Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), TU Dortmund, Dortmund, Germany
| | - Sam Kacew
- McLaughlin Centre for Risk Assessment, University of Ottawa, Ottawa, Canada
| | | | - Olavi Pelkonen
- Department of Pharmacology and Toxicology, University of Oulu, Oulu, Finland
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Helsinki, Finland
| | - Pat Heslop-Harrison
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Nico P Vermeulen
- Department of Chemistry & Pharmaceutical Sciences, Vrije Universiteit, Amsterdam, the Netherlands
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5
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Autrup H, Barile FA, Berry SC, Blaauboer BJ, Boobis A, Bolt H, Borgert CJ, Dekant W, Dietrich D, Domingo JL, Gori GB, Greim H, Hengstler J, Kacew S, Marquardt H, Pelkonen O, Savolainen K, Heslop-Harrison P, Vermeulen NP. Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity. How to evaluate the risk of the S-EDCs? ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2020; 78:103396. [PMID: 32391796 DOI: 10.1016/j.etap.2020.103396] [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: 04/07/2020] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.
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Affiliation(s)
- Herman Autrup
- Institute of Public Health, University of Aarhus, Aarhus, Denmark
| | - Frank A Barile
- College of Pharmacy and Health Sciences, St John's University, Queens, New York, USA
| | | | - Bas J Blaauboer
- Division of Toxicology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Alan Boobis
- National Heart & Lung Institute, Imperial College, London, UK
| | - Herrmann Bolt
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), TU Dortmund, Dortmund, Germany
| | | | - Wolfgang Dekant
- Department of Toxicology, University of Wuerzburg, Wuerzburg, Germany.
| | - Daniel Dietrich
- Human and Environmental Toxicology, University of Konstanz, Konstanz, Germany
| | - Jose L Domingo
- Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat 'Rovira i Virgili', Reus, Spain
| | | | - Helmut Greim
- Institute of Public Health, University of Aarhus, Aarhus, Denmark.
| | - Jan Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), TU Dortmund, Dortmund, Germany
| | - Sam Kacew
- McLaughlin Centre for Risk Assessment, University of Ottawa, Ottawa, Canada
| | | | - Olavi Pelkonen
- Department of Pharmacology and Toxicology, University of Oulu, Oulu, Finland
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Helsinki, Finland
| | - Pat Heslop-Harrison
- Department of Genetics and Genome Biology University of Leicester, Leicester, UK
| | - Nico P Vermeulen
- Department of Chemistry & Pharmaceutical Sciences, Vrije Universiteit, Amsterdam, The Netherlands
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6
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Autrup H, Barile FA, Berry SC, Blaauboer BJ, Boobis A, Bolt H, Hengstler J, Borgert CJ, Dekant W, Dietrich D, Domingo JL, Gori GB, Greim H, Kacew S, Marquardt H, Pelkonen O, Savolainen K, Heslop-Harrison P, Vermeulen NP. Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity. How to evaluate the risk of the S-EDCs? Food Chem Toxicol 2020; 142:111349. [DOI: 10.1016/j.fct.2020.111349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 04/09/2020] [Indexed: 12/17/2022]
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7
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Autrup H, Barile FA, Berry SC, Blaauboer BJ, Boobis A, Bolt H, Borgert CJ, Dekant W, Dietrich D, Domingo JL, Gori GB, Greim H, Hengstler J, Kacew S, Marquardt H, Pelkonen O, Savolainen K, Heslop-Harrison P, Vermeulen NP. Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity. How to evaluate the risk of the S-EDCs? Chem Biol Interact 2020; 326:109099. [DOI: 10.1016/j.cbi.2020.109099] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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8
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Autrup H, Barile FA, Berry SC, Blaauboer BJ, Boobis A, Bolt H, Borgert CJ, Dekant W, Dietrich D, Domingo JL, Gori GB, Greim H, Hengstler J, Kacew S, Marquardt H, Pelkonen O, Savolainen K, Heslop-Harrison P, Vermeulen NP. Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity. How to evaluate the risk of the S-EDCs? JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2020; 83:485-494. [PMID: 32552445 DOI: 10.1080/15287394.2020.1756592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Theoretically, both synthetic endocrine-disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine-disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower than S-EDCs. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea, and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.
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Affiliation(s)
- Herman Autrup
- Institute of Public Health, University of Aarhus , Aarhus, Denmark
| | - Frank A Barile
- College of Pharmacy and Health Sciences, St John's University , Queens, USA
| | | | - Bas J Blaauboer
- Division of Toxicology, Institute for Risk Assessment Sciences, Utrecht University , Utrecht, The Netherlands
| | - Alan Boobis
- National Heart & Lung Institute, Imperial College , London, UK
| | - Herrmann Bolt
- Leibniz Research Centre for Working Environment and Human Factors (Ifado), TU Dortmund , Dortmund, Germany
| | | | - Wolfgang Dekant
- Department of Toxicology, University of Wuerzburg , Wuerzburg, Germany
| | - Daniel Dietrich
- Human and Environmental Toxicology, University of Konstanz , Konstanz, Germany
| | - Jose L Domingo
- Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat 'Rovira I Virgili' , Reus, Spain
| | | | - Helmut Greim
- Technical University of Munich D-85350, Freising-Weihenstephan, Germany
| | - Jan Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (Ifado), TU Dortmund , Dortmund, Germany
| | - Sam Kacew
- McLaughlin Centre for Risk Assessment, University of Ottawa , Ottawa, Canada
| | | | - Olavi Pelkonen
- Department of Pharmacology and Toxicology, University of Oulu , Finland
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health , Helsinki, Finland
| | - Pat Heslop-Harrison
- Department of Genetics and Genome Biology, University of Leicester , Leicester, UK
| | - Nico P Vermeulen
- Department of Chemistry & Pharmaceutical Sciences, Vrije Universiteit , Amsterdam, The Netherlands
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Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity: how to evaluate the risk of the S-EDCs? Arch Toxicol 2020; 94:2549-2557. [PMID: 32514609 PMCID: PMC7367909 DOI: 10.1007/s00204-020-02800-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 05/28/2020] [Indexed: 12/21/2022]
Abstract
Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.
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Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity. How to evaluate the risk of the S-EDCs? Toxicol In Vitro 2020; 67:104861. [PMID: 32360643 DOI: 10.1016/j.tiv.2020.104861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.
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Fountoucidou P, Veskoukis AS, Kerasioti E, Docea AO, Taitzoglou IA, Liesivuori J, Tsatsakis A, Kouretas D. A mixture of routinely encountered xenobiotics induces both redox adaptations and perturbations in blood and tissues of rats after a long-term low-dose exposure regimen: The time and dose issue. Toxicol Lett 2019; 317:24-44. [PMID: 31541690 DOI: 10.1016/j.toxlet.2019.09.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/05/2019] [Accepted: 09/14/2019] [Indexed: 02/08/2023]
Abstract
Exposure of humans to xenobiotic mixtures is a continuous state during their everyday routine. However, the majority of toxicological studies assess the in vivo effects of individual substances rather than mixtures. Therefore, our main objective was to evaluate the impact of the 12- and 18-month exposure of rats to a mixture containing 13 pesticides, food, and life-style additives in three dosage levels (i.e. 0.0025 × NOAEL, 0.01 × NOAEL, and 0.05 × NOAEL), on redox biomarkers in blood and tissues. Our results indicate that the exposure to the mixture induces physiological adaptations by enhancing the blood antioxidant mechanism (i.e., increased glutathione, catalase and total antioxidant capacity and decreased protein carbonyls and TBARS) at 12 months of exposure. On the contrary, exposure to the 0.05 × NOAEL dose for 18 months induces significant perturbations in blood and tissue redox profile (i.e., increased carbonyls and TBARS). This study simulates a scenario of real-life risk exposure to mixtures of xenobiotics through a long-term low-dose administration regimen in rats. The results obtained could support, at least in part, the necessity of introducing testing of combined stimuli at reference doses and long term for the evaluation of the risk from exposure to chemicals.
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Affiliation(s)
- Polyxeni Fountoucidou
- Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500, Larissa, Greece
| | - Aristidis S Veskoukis
- Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500, Larissa, Greece
| | - Efthalia Kerasioti
- Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500, Larissa, Greece
| | - Anca Oana Docea
- Department of Toxicology, University of Medicine and Pharmacy, Faculty of Pharmacy, Craiova, 200349, Romania
| | - Ioannis A Taitzoglou
- School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Greece
| | | | - Aristidis Tsatsakis
- Center of Toxicology Science & Research, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Demetrios Kouretas
- Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, Mezourlo, 41500, Larissa, Greece.
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Combarnous Y, Nguyen TMD. Comparative Overview of the Mechanisms of Action of Hormones and Endocrine Disruptor Compounds. TOXICS 2019; 7:toxics7010005. [PMID: 30682876 PMCID: PMC6468742 DOI: 10.3390/toxics7010005] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 12/23/2022]
Abstract
Endocrine Disruptor Compounds (EDCs) are synthetic or natural molecules in the environment that promote adverse modifications of endogenous hormone regulation in humans and/or in wildlife animals. In the present paper, we review the potential mechanisms of EDCs and point out the similarities and differences between EDCs and hormones. There was only one mechanism, out of nine identified, in which EDCs acted like hormones (i.e. binding and stimulated hormone receptor activity). In the other eight identified mechanisms of action, EDCs exerted their effects either by affecting endogenous hormone concentration, or its availability, or by modifying hormone receptor turn over. This overview is intended to classify the various EDC mechanisms of action in order to better appreciate when in vitro tests would be valid to assess their risks towards humans and wildlife.
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Affiliation(s)
- Yves Combarnous
- CNRS, INRA, Physiologie de la Reproduction & des Comportements, 37380 Nouzilly, France.
| | - Thi Mong Diep Nguyen
- CNRS, INRA, Physiologie de la Reproduction & des Comportements, 37380 Nouzilly, France.
- Faculty of Biology-Agricultural Engineering, Quy Nhon University, Binh Dinh 820000, Vietnam.
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Tsatsakis A, Goumenou M, Liesivuori J, Dekant W, Hernández AF. Toxicology for real-life risk simulation - Editorial preface to this special issue. Toxicol Lett 2018; 309:33-34. [PMID: 30557596 DOI: 10.1016/j.toxlet.2018.12.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Aristidis Tsatsakis
- Centre of Toxicology Science & Research, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Marina Goumenou
- Centre of Toxicology Science & Research, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Jyrki Liesivuori
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
| | - Wolfgang Dekant
- Institute of Toxicology, University of Wuerzburg, Versbacherstrasse 9, 97078 Wuerzburg, Germany
| | - Antonio F Hernández
- Department of Legal Medicine and Toxicology, University of Granada School of Medicine, Granada, Spain
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Olukole SG, Ajani SO, Ola-Davies EO, Lanipekun DO, Aina OO, Oyeyemi MO, Oke BO. Melatonin ameliorates bisphenol A-induced perturbations of the prostate gland of adult Wistar rats. Biomed Pharmacother 2018; 105:73-82. [PMID: 29843047 DOI: 10.1016/j.biopha.2018.05.125] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 05/22/2018] [Accepted: 05/23/2018] [Indexed: 02/04/2023] Open
Abstract
Bisphenol A (BPA) is an endocrine disrupting chemical (EDC) that has been demonstrated to induce alterations in reproductive organs while melatonin (ML), an antioxidant, present in plants and animals, is capable of protecting against EDC-induced alterations. Adult male Wistar rats (average weight, 240 + 10 g) were divided into four groups of ten animals each: Rats in group I (control) received oral 0.2 ml 1% dimethyl sulfoxide (DMSO)/99% canola oil as vehicle; group II received intra-peritoneal 10 mg/kg BW/day ML. Group III received oral BPA dissolved in DMSO and solubilized in canola oil at 10 mg/kg BW/day. Group IV were treated with same dose of BPA as group III with a concomitant intra-peritoneal 10 mg/kg BW/day ML. All treatments lasted for 14 days. BPA significantly increased the prostatic index of the rats while ML ameliorated it. BPA significantly increased serum levels of estrogen as well as prostate-specific antigen but decreased serum testosterone in the rats while concomitant treatment with ML ameliorated these alterations. Also, BPA caused vascular congestion, hyperplasia (functional, reactive and atypical) of prostatic epithelium as well as tubular atrophy the rats while ML attenuated the observed lesions. Decreased localization of αSmooth muscle actin, vimentin and S100 proteins were observed in the BPA-treated rats while these decreases were ameliorated by ML. The present study has shown that sub-acute oral administration of BPA induced alterations in prostatic index, serum hormone levels, down-regulated protein localization and induced morphological lesions of the prostate gland in rats while concomitant treatment with intra-peritoneal ML ameliorated these conditions. Hence, low dose of ML can protect against BPA-induced toxicity of the prostate gland of rats.
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Affiliation(s)
- Samuel Gbadebo Olukole
- Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Ibadan, Nigeria.
| | - Samuel Olumide Ajani
- Department of Theriogenology, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
| | - Eunice Olufunke Ola-Davies
- Department of Veterinary Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
| | | | | | | | - Bankole Olusiji Oke
- Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Ibadan, Nigeria
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Sidorkiewicz I, Zaręba K, Wołczyński S, Czerniecki J. Endocrine-disrupting chemicals-Mechanisms of action on male reproductive system. Toxicol Ind Health 2017; 33:601-609. [PMID: 28464759 DOI: 10.1177/0748233717695160] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Endocrine-disrupting chemicals (EDCs) are exogenous compounds that can cause disturbances in the endocrine system and have multiple harmful effects on health by targeting different organs and systems in the human body. Mass industrial production and widespread use of EDCs have resulted in worldwide contamination. Accumulating evidence suggest that human exposure to EDCs is related to the impairment of male reproductive function and can interrupt other hormonally regulated metabolic processes, particularly if exposure occurs during early development. Investigation of studies absent in previous reviews and meta-analysis of adverse effects of EDCs on functioning of the male reproductive system is the core of this work. Four main modes of action of EDCs on male fertility have been summarized in this review. First, studies describing estrogen- pathway disturbing chemicals are investigated. Second, androgen-signaling pathway alterations and influence on androgen sensitive tissues are examined. Third, evaluation of steroidogenesis dysfunction is discussed by focusing on the steroid hormone biosynthesis pathway, which is targeted by EDCs. Last, the reportedly destructive role of reactive oxygen species (ROS) on sperm function is discussed. Spermatogenesis is a remarkably complex process, hence multiple studies point out various dysfunctions depending on the development state at which the exposure occurred. Collected data show the need to account for critical windows of exposure such as fetal, perinatal and pubertal periods as well as effects of mixtures of several compounds in future research.
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Affiliation(s)
- Iwona Sidorkiewicz
- 1 Department of Reproduction and Gynecological Endocrinology, Medical University of Białystok, Białystok, Poland
| | - Kamil Zaręba
- 1 Department of Reproduction and Gynecological Endocrinology, Medical University of Białystok, Białystok, Poland
| | - Sławomir Wołczyński
- 1 Department of Reproduction and Gynecological Endocrinology, Medical University of Białystok, Białystok, Poland.,2 Department of Biology and Pathology of Human Reproduction, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland
| | - Jan Czerniecki
- 2 Department of Biology and Pathology of Human Reproduction, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland
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Ahbab MA, Barlas N, Karabulut G. The toxicological effects of bisphenol A and octylphenol on the reproductive system of prepubertal male rats. Toxicol Ind Health 2016; 33:133-146. [DOI: 10.1177/0748233715603847] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of the present study was to assess and compare the individual adverse effects of bisphenol A (BPA) and octylphenol (OP) on the reproductive system of prepubertal male rats. Rats were exposed to BPA and OP at doses of 125 and 250 mg/kg/day, by gavage, for 90 days. At the end of the study, the testes, epididymis, prostate gland, and seminal vesicle were removed and examined histopathologically. Also, 3-β-hydroxysteroid dehydrogenase expressions were analyzed and serum testosterone and luteinizing hormone (LH) levels were measured. Sperm head count of caput epididymis was performed using a hemocytometer. Seminiferous and epididymal round tubules were evaluated for tubule diameter, lumen diameter, and height of tubule epithelium. There were significant increases in relative testes weights in BPA125, OP125, and OP250 groups compared with the control. Atrophic tubules, pyknotic tubules, combined tubules, congestion, vacuolization of Sertoli cell, cell debris in the lumen, tubules without sperm, and degeneration of tubules were noted in the tissue specimens obtained from the treatment groups compared with the control group. Sperm head counts were decreased in all treatment groups except for the low-dose BPA group. Testosterone (T) levels decreased in the BPA and high-dose OP treatment groups. LH levels increased in BPA treatment groups and the low-dose OP treatment group and decreased in the high-dose OP group. Epithelial height of high-dose BPA and OP treatment groups increased compared with the control group. Furthermore tubular height of low-dose BPA and high-dose OP groups increased with respect to control levels. In the OP250 treatment group, thyroxine hormone level was increased compared to other groups. Also, in the OP125 treatment group, triiodothyronine hormone level was increased compared with other groups. The results of this study showed that BPA and OP affect the steroidogenic enzyme expression and T production in Leydig cells. In conclusion, BPA and OP have adverse effects on the male reproductive system of prepubertal rats.
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Affiliation(s)
| | - Nurhayat Barlas
- Department of Biology, Faculty of Science, Hacettepe University, Ankara, Turkey
| | - Gözde Karabulut
- Department of Biology, Faculty of Science, Hacettepe University, Ankara, Turkey
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17
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Comparing effect levels of regulatory studies with endpoints derived in targeted anti-androgenic studies: example prochloraz. Arch Toxicol 2016; 91:143-162. [DOI: 10.1007/s00204-016-1678-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 01/28/2016] [Indexed: 01/05/2023]
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Lamb JC, Boffetta P, Foster WG, Goodman JE, Hentz KL, Rhomberg LR, Staveley J, Swaen G, Van Der Kraak G, Williams AL. Comments on the opinions published by Bergman et al. (2015) on Critical Comments on the WHO-UNEP State of the Science of Endocrine Disrupting Chemicals (Lamb et al., 2014). Regul Toxicol Pharmacol 2015; 73:754-7. [PMID: 26550933 DOI: 10.1016/j.yrtph.2015.10.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 10/28/2015] [Indexed: 01/01/2023]
Abstract
Recently Bergman et al. (2015) took issue with our comments (Lamb et al., 2014) on the WHO-UNEP(1) report entitled the "State of the Science of Endocrine Disrupting Chemicals - 2012" (WHO 2013a). We find several key differences between their view and ours regarding the selection of studies and presentation of data related to endocrine disrupting chemicals (EDCs) under the WHO-IPCS(2) definition (2002). In this response we address the factors that we think are most important: 1. the difference between hazard and risk; 2. the different approaches for hazard identification (weight of the evidence [WOE] vs. emphasizing positive findings over null results); and 3. the lack of a justification for conceptual or practical differences between EDCs and other groups of agents.
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Affiliation(s)
- James C Lamb
- Exponent, 1800 Diagonal Road, Suite #500, Alexandria, VA 22314, USA.
| | - Paolo Boffetta
- The Tisch Cancer Institute and Institute for Translational Epidemiology, Icahn School of Medicine at Mount Sinai, 17 East 102 Street Floor West Tower, 5th Floor Room 5-142, New York, NY 10029, USA.
| | - Warren G Foster
- Department of Obstetrics & Gynecology, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada.
| | | | - Karyn L Hentz
- Exponent, 1800 Diagonal Road, Suite #500, Alexandria, VA 22314, USA.
| | | | - Jane Staveley
- Exponent, 1800 Diagonal Road, Suite #500, Alexandria, VA 22314, USA.
| | | | - Glen Van Der Kraak
- Department of Integrative Biology, University of Guelph, Guelph ON N1G 2W1, Canada.
| | - Amy L Williams
- Exponent, 1800 Diagonal Road, Suite #500, Alexandria, VA 22314, USA.
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Autrup H, Barile FA, Blaauboer BJ, Degen GH, Dekant W, Dietrich D, Domingo JL, Gori GB, Greim H, Hengstler JG, Kacew S, Marquardt H, Pelkonen O, Savolainen K, Vermeulen NP. Principles of Pharmacology and Toxicology Also Govern Effects of Chemicals on the Endocrine System. Toxicol Sci 2015; 146:11-5. [PMID: 26026993 DOI: 10.1093/toxsci/kfv082] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The present debate on chemicals with Hormonal activity, often termed 'endocrine disruptors', is highly controversial and includes challenges of the present paradigms used in toxicology and in hazard identification and risk characterization. In our opinion, chemicals with hormonal activity can be subjected to the well-evaluated health risk characterization approach used for many years including adverse outcome pathways. Many of the points arguing for a specific approach for risk characterization of chemicals with hormonal activity are based on highly speculative conclusions. These conclusions are not well supported when evaluating the available information.
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Affiliation(s)
- Herman Autrup
- International Union of Toxicologists, Institute of Public Health, University of Aarhus, Aarhus, Denmark
| | - Frank A Barile
- College of Pharmacy and Health Sciences, St John's University, Queens, New York, USA
| | - Bas J Blaauboer
- Division of Toxicology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Gisela H Degen
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), TU Dortmund, Dortmund, Germany
| | - Wolfgang Dekant
- Department of Toxicology, University of Wuerzburg, Wuerzburg, Germany;
| | - Daniel Dietrich
- Faculty of Biology, University of Konstanz, Konstanz, Germany
| | - Jose L Domingo
- Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat 'Rovira i Virgili', Reus, Spain
| | | | | | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), TU Dortmund, Dortmund, Germany
| | - Sam Kacew
- McLaughlin Centre for Risk Assessment, University of Ottawa, Ottawa, Canada
| | | | - Olavi Pelkonen
- Department of Pharmacology and Toxicology, University of Oulu, Oulu, Finland
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Helsinki Finland
| | - Nico P Vermeulen
- Department of Chemistry & Pharmaceutical Sciences, Vrije Universiteit, Amsterdam, The Netherlands
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20
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Futran Fuhrman V, Tal A, Arnon S. Why endocrine disrupting chemicals (EDCs) challenge traditional risk assessment and how to respond. JOURNAL OF HAZARDOUS MATERIALS 2015; 286:589-611. [PMID: 25646754 DOI: 10.1016/j.jhazmat.2014.12.012] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 12/02/2014] [Accepted: 12/08/2014] [Indexed: 05/11/2023]
Abstract
Endocrine disrupting compounds (EDCs) are a diverse group of "chemicals of emerging concern" which have attracted much interest from the research community since the 1990s. Today there is still no definitive risk assessment tool for EDCs. While some decision making organizations have attempted to design methodology guidelines to evaluate the potential risk from this broadly defined group of constituents, risk assessors still face many uncertainties and unknowns. Until a risk assessment paradigm is designed specifically for EDCs and is vetted by the field, traditional risk assessment tools may be used with caution to evaluate EDCs. In doing so, each issue of contention should be addressed with transparency in order to leverage available information and technology without sacrificing integrity or accuracy. The challenges that EDCs pose to traditional risk assessment are described in this article to assist in this process.
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Affiliation(s)
- Vivian Futran Fuhrman
- Institute for Dryland, Environmental and Desert Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
| | - Alon Tal
- Institute for Dryland, Environmental and Desert Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
| | - Shai Arnon
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
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Felter SP, Daston GP, Euling SY, Piersma AH, Tassinari MS. Assessment of health risks resulting from early-life exposures: Are current chemical toxicity testing protocols and risk assessment methods adequate? Crit Rev Toxicol 2015; 45:219-44. [PMID: 25687245 DOI: 10.3109/10408444.2014.993919] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract Over the last couple of decades, the awareness of the potential health impacts associated with early-life exposures has increased. Global regulatory approaches to chemical risk assessment are intended to be protective for the diverse human population including all life stages. However, questions persist as to whether the current testing approaches and risk assessment methodologies are adequately protective for infants and children. Here, we review physiological and developmental differences that may result in differential sensitivity associated with early-life exposures. It is clear that sensitivity to chemical exposures during early-life can be similar, higher, or lower than that of adults, and can change quickly within a short developmental timeframe. Moreover, age-related exposure differences provide an important consideration for overall susceptibility. Differential sensitivity associated with a life stage can reflect the toxicokinetic handling of a xenobiotic exposure, the toxicodynamic response, or both. Each of these is illustrated with chemical-specific examples. The adequacy of current testing protocols, proposed new tools, and risk assessment methods for systemic noncancer endpoints are reviewed in light of the potential for differential risk to infants and young children.
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Laurenson JP, Bloom RA, Page S, Sadrieh N. Ethinyl estradiol and other human pharmaceutical estrogens in the aquatic environment: a review of recent risk assessment data. AAPS J 2014; 16:299-310. [PMID: 24470211 PMCID: PMC3933577 DOI: 10.1208/s12248-014-9561-3] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 01/02/2014] [Indexed: 11/30/2022] Open
Abstract
Interest in pharmaceuticals in the environment has increased substantially in recent years. Several studies in particular have assessed human and ecological risks from human pharmaceutical estrogens, such as 17α-ethinyl estradiol (EE2). Regulatory action also has increased, with the USA and other countries developing rules to address estrogens and other pharmaceuticals in the environment. Accordingly, the Center for Drug Evaluation and Research at the US Food and Drug Administration has conducted a review and analysis of current data on the long-term ecological exposure and effects of EE2 and other estrogens. The results indicate that mean-flow long-term predicted environmental concentrations (PECs) of EE2 in approximately 99% or more of US surface water segments downstream of wastewater treatment plants are lower than a predicted no-effect concentration (PNEC) for aquatic chronic toxicity of 0.1 ng/L. Exceedances are expected to be primarily in localized, effluent-dominated water segments. The median mean-flow PEC is more than two orders of magnitude lower than this PNEC. Similar results exist for other pharmaceutical estrogens. Data also suggest that the contribution of EE2 more broadly to total estrogenic load in the environment from all sources (including other human pharmaceutical estrogens, endogenous estrogens, natural environmental estrogens, and industrial chemicals), while highly uncertain and variable, appears to be relatively low overall. Additional data and a more comprehensive approach for data collection and analysis for estrogenic substances in the environment, especially in effluent-dominated water segments in sensitive environments, would more fully characterize the risks.
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Affiliation(s)
- James P Laurenson
- Office of Pharmaceutical Science, Center for Drug Evaluation and Research, US Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland, 20903, USA,
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Nohynek GJ, Borgert CJ, Dietrich D, Rozman KK. Endocrine disruption: fact or urban legend? Toxicol Lett 2013; 223:295-305. [PMID: 24177261 DOI: 10.1016/j.toxlet.2013.10.022] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 10/02/2013] [Accepted: 10/21/2013] [Indexed: 10/26/2022]
Abstract
Endocrine disruptors (EDs) are substances that cause adverse health effects via endocrine-mediated mechanisms in an intact organism or its progeny or (sub) populations. Purported EDCs in personal care products include 4-MBC (UV filter) or parabens that showed oestrogenic activity in screening tests, although regulatory toxicity studies showed no adverse effects on reproductive endpoints. Hormonal potency is the key issue of the safety of EDCs. Oestrogen-based drugs, e.g. the contraceptive pill or the synthetic oestrogen DES, possess potencies up to 7 orders of magnitude higher than those of PCP ingredients; yet, in utero exposure to these drugs did not adversely affect fertility or sexual organ development of offspring unless exposed to extreme doses. Additive effects of EDs are unlikely due to the multitude of mechanisms how substances may produce a hormone-like activity; even after uptake of different substances with a similar mode of action, the possibility of additive effects is reduced by different absorption, metabolism and kinetics. This is supported by a number of studies on mixtures of chemical EDCs. Overall, despite of 20 years of research a human health risk from exposure to low concentrations of exogenous chemical substances with weak hormone-like activities remains an unproven and unlikely hypothesis.
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