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O'Shaughnessy KL, Sasser AL, Bell KS, Riutta C, Ford JL, Grindstaff RD, Gilbert ME. Bypassing the brain barriers: upregulation of serum miR-495 and miR-543-3p reflects thyroid-mediated developmental neurotoxicity in the rat. Toxicol Sci 2024; 198:128-140. [PMID: 38070162 DOI: 10.1093/toxsci/kfad125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024] Open
Abstract
Evaluating the neurodevelopmental effects of thyroid-disrupting chemicals is challenging. Although some standardized developmental and reproductive toxicity studies recommend serum thyroxine (T4) measures in developing rats, extrapolating between a serum T4 reduction and neurodevelopmental outcomes is not straightforward. Previously, we showed that the blood-brain and blood-cerebrospinal fluid barriers may be affected by developmental hypothyroidism in newborn rats. Here, we hypothesized that if the brain barriers were functionally disturbed by abnormal thyroid action, then small molecules may escape from the brain tissue and into general circulation. These small molecules could then be identified in blood samples, serving as a direct readout of thyroid-mediated developmental neurotoxicity. To address these hypotheses, pregnant rats were exposed to propylthiouracil (PTU, 0 or 3 ppm) to induce thyroid hormone insufficiency, and dams were permitted to give birth. PTU significantly reduced serum T4 in postnatal offspring. Consistent with our hypothesis, we show that tight junctions of the brain barriers were abnormal in PTU-exposed pups, and the blood-brain barrier exhibited increased permeability. Next, we performed serum microRNA Sequencing (miRNA-Seq) to identify noncoding RNAs that may reflect these neurodevelopmental disturbances. Of the differentially expressed miRNAs identified, 7 were upregulated in PTU-exposed pups. Validation by qRT-PCR shows that miR-495 and miR-543-3p were similarly upregulated in males and females. Interestingly, these miRNAs have been linked to cell junction dysfunction in other models, paralleling the identified abnormalities in the rat brain. Taken together, these data show that miR-495 and miR-543-3p may be novel in vivo biomarkers of thyroid-mediated developmental neurotoxicity.
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Affiliation(s)
- Katherine L O'Shaughnessy
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Aubrey L Sasser
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37831, USA
| | - Kiersten S Bell
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37831, USA
| | - Cal Riutta
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37831, USA
| | - Jermaine L Ford
- Chemical Characterization and Exposure Division, Center for Computational Toxicology and Exposure, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Rachel D Grindstaff
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
| | - Mary E Gilbert
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27709, USA
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Kim JY, Park Y, Lee SH, Park E, Lee H. Comparative study on estrogen receptor alpha dimerization and transcriptional activity of parabens. Toxicol Res 2024; 40:153-161. [PMID: 38223674 PMCID: PMC10786792 DOI: 10.1007/s43188-023-00212-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 08/27/2023] [Accepted: 09/21/2023] [Indexed: 01/16/2024] Open
Abstract
Parabens are used as preservatives in various household products, including oral products, cosmetics, and hair/body washes. In recent years, the widespread use of parabens has raised concerns due to the potential health risks associated with their estrogenic effects. In the present study, we evaluated and compared the estrogenic activity of parabens using two cell-based in vitro tests: (1) bioluminescence resonance energy transfer (BRET)-based estrogen receptor alpha (ERα) dimerization using HEK293 cells that were stably transfected with ERα-fused NanoLuc luciferase (Nluc) and HaloTag (HT) expression vector, and (2) stably transfected transcriptional activation (STTA) assays using ERα-HeLa9903 cells. The following parabens were tested using the BRET-based ERα dimerization assay and showed estrogenic activity (PC20 values): methyl paraben (MP, 5.98 × 10-5 M), ethyl paraben (EP, 3.29 × 10-5 M), propylparaben (PP, 3.09 × 10-5 M), butyl paraben (BP, 2.58 × 10-5 M), isopropyl paraben (IsoPP, 1.37 × 10-5 M), and isobutyl paraben (IsoBP, 1.43 × 10-5 M). Except MP, all other parabens tested using the STTA assay also showed estrogenic activity: EP, 7.57 × 10-6 M; PP, 1.18 × 10-6 M; BP, 3.02 × 10-7 M; IsoPP, 3.58 × 10-7 M; and IsoBP, 1.80 × 10-7 M. Overall, EP, PP, BP, IsoPP, and IsoBP tested positive for estrogenic activity using both assays. These findings demonstrate that most parabens, albeit not all, induce ERα dimerization and possess estrogenic activity.
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Affiliation(s)
- Jong-Yeon Kim
- Department of Food Science and Biotechnology, Gachon University, Seongnam, 13120 Republic of Korea
| | - Yooheon Park
- Department of Food Science and Biotechnology, Dongguk University, Goyang, 10326 Republic of Korea
| | - Seok-Hee Lee
- Department of Food Science and Biotechnology, Dongguk University, Goyang, 10326 Republic of Korea
| | - Eun‐Jung Park
- Department of Food and Nutrition, Gachon University, Seongnam, Gyeonggi‐do 13120 Republic of Korea
- Institute for Aging and Clinical Nutrition Research, Gachon University, Seongnam, 13120 Republic of Korea
| | - Hae‐Jeung Lee
- Department of Food Science and Biotechnology, Gachon University, Seongnam, 13120 Republic of Korea
- Department of Food and Nutrition, Gachon University, Seongnam, Gyeonggi‐do 13120 Republic of Korea
- Institute for Aging and Clinical Nutrition Research, Gachon University, Seongnam, 13120 Republic of Korea
- Department of Health Sciences and Technology, GAIHST, Gachon University, Incheon, 21999 Republic of Korea
- Gachon University Gil Medical Center, Incheon, 21565 Republic of Korea
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Melching-Kollmuss S, Bothe K, Charlton A, Gangadharan B, Ghaffari R, Jacobi S, Marty S, Marxfeld HA, McInnes EF, Sauer UG, Sheets LP, Strupp C, Tinwell H, Wiemann C, Botham PA, van Ravenzwaay B. Towards a science-based testing strategy to identify maternal thyroid hormone imbalance and neurodevelopmental effects in the progeny - Part IV: the ECETOC and CLE Proposal for a Thyroid Function-Related Neurodevelopmental Toxicity Testing and Assessment Scheme (Thyroid-NDT-TAS). Crit Rev Toxicol 2023; 53:339-371. [PMID: 37554099 DOI: 10.1080/10408444.2023.2231033] [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: 03/14/2023] [Revised: 06/22/2023] [Accepted: 06/22/2023] [Indexed: 08/10/2023]
Abstract
Following the European Commission Endocrine Disruptor Criteria, substances shall be considered as having endocrine disrupting properties if they (a) elicit adverse effects, (b) have endocrine activity, and (c) the two are linked by an endocrine mode-of-action (MoA) unless the MoA is not relevant for humans. A comprehensive, structured approach to assess whether substances meet the Endocrine Disruptor Criteria for the thyroid modality (EDC-T) is currently unavailable. Here, the European Centre for Ecotoxicology and Toxicology of Chemicals Thyroxine Task Force and CropLife Europe propose a Thyroid Function-Related Neurodevelopmental Toxicity Testing and Assessment Scheme (Thyroid-NDT-TAS). In Tier 0, before entering the Thyroid-NDT-TAS, all available in vivo, in vitro and in silico data are submitted to weight-of-evidence (WoE) evaluations to determine whether the substance of interest poses a concern for thyroid disruption. If so, Tier 1 of the Thyroid-NDT-TAS includes an initial MoA and human relevance assessment (structured by the key events of possibly relevant adverse outcome pathways) and the generation of supportive in vitro/in silico data, if relevant. Only if Tier 1 is inconclusive, Tier 2 involves higher-tier testing to generate further thyroid- and/or neurodevelopment-related data. Tier 3 includes the final MoA and human relevance assessment and an overarching WoE evaluation to draw a conclusion on whether, or not, the substance meets the EDC-T. The Thyroid-NDT-TAS is based on the state-of-the-science, and it has been developed to minimise animal testing. To make human safety assessments more accurate, it is recommended to apply the Thyroid-NDT-TAS during future regulatory assessments.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Ursula G Sauer
- Scientific Consultancy - Animal Welfare, Neubiberg, Germany
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Casas-Rodríguez A, Moyano R, Molina-Hernández V, Cameán AM, Jos A. Potential oestrogenic effects (following the OECD test guideline 440) and thyroid dysfunction induced by pure cyanotoxins (microcystin-LR, cylindrospermopsin) in rats. ENVIRONMENTAL RESEARCH 2023; 226:115671. [PMID: 36907345 DOI: 10.1016/j.envres.2023.115671] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
Potential endocrine-disrupting properties of cyanotoxins, such as microcystin-LR (MC-LR) and cylindrospermopsin (CYN) are of concern due to their increasing occurrence, the scarcity of reports on the topic (particularly for CYN) and the impact of human's health at different levels. Thus, this work performed for the first time the uterotrophic bioassay in rats, following the Organization for Economic Cooperation and Development (OECD) Test Guideline 440, to explore the oestrogenic properties of CYN and MC-LR (75, 150, 300 μg/kg b.w./day) in ovariectomized (OVX) rats. Results revealed neither changes in the wet and blotted uterus weights nor in the morphometric study of uteri. Moreover, among the steroid hormones analysed in serum, the most remarkable effect was the dose-dependent increase in progesterone (P) levels in rats exposed to MC-LR. Additionally, a histopathology study of thyroids and serum levels of thyroids hormones were determined. Tissue affectation (follicular hypertrophy, exfoliated epithelium, hyperplasia) was observed, as well as increased T3 and T4 levels in rats exposed to both toxins. Taken together, these results point out that CYN and MC-LR are not oestrogenic compounds at the conditions tested in the uterotrophic assay in OVX rats, but, however, thyroid disruption effects cannot be discarded.
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Affiliation(s)
- Antonio Casas-Rodríguez
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, Profesor García González n°2, 41012, Seville, Spain
| | - Rosario Moyano
- Departamento de Anatomía y Anatomía Patológica Comparadas y Toxicología, Facultad de Veterinaria, UIC Zoonosis y Enfermedades Emergentes ENZOEM, Universidad de Cordoba, Edificio de Sanidad Animal, Campus de Rabanales, Ctra. Madrid-Cádiz Km 396, 14014, Córdoba, Spain
| | - Verónica Molina-Hernández
- Departamento de Anatomía y Anatomía Patológica Comparadas y Toxicología, Facultad de Veterinaria, UIC Zoonosis y Enfermedades Emergentes ENZOEM, Universidad de Cordoba, Edificio de Sanidad Animal, Campus de Rabanales, Ctra. Madrid-Cádiz Km 396, 14014, Córdoba, Spain
| | - Ana María Cameán
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, Profesor García González n°2, 41012, Seville, Spain.
| | - Angeles Jos
- Area of Toxicology, Faculty of Pharmacy, Universidad de Sevilla, Profesor García González n°2, 41012, Seville, Spain
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Dziwenka M, Coppock R, Davidson MH, Weder MA. Toxicological safety assessment of HempChoice® hemp oil extract; a proprietary extract consisting of a high concentration of cannabidiol (CBD) in addition to other phytocannabinoids and terpenes derived from CannabissativaL. Heliyon 2023; 9:e16913. [PMID: 37313165 PMCID: PMC10258502 DOI: 10.1016/j.heliyon.2023.e16913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 05/30/2023] [Accepted: 06/01/2023] [Indexed: 06/15/2023] Open
Abstract
HempChoice® Hemp Oil Extract (Geocann, LLC) is an extract of the aerial parts of hemp (Cannabis sativa L.) primarily comprised of 55-75% cannabidiol (CBD), 1-15% other phytocannabinoids and 1-15% terpenes. The results of multiple safety studies demonstrated that it was non-mutagenic in an Ames and mammalian cell micronucleus. test and was well tolerated in a 14-day range-finding study at dose levels up to 96.03. mg/kg BW/day. In the 90-day study, no HempChoice® Hemp Oil Extract-related significant changes were noted in weekly BW, daily BW gain, food consumption, functional observational battery or motor activity assessment. In addition, no HempChoice® Hemp Oil Extract related mortalities, abnormal clinical observations and ophthalmological changes were reported. Some HempChoice® Hemp Oil Extract-related changes were reported in the hematology and clinical chemistry parameters evaluated. These changes were not outside the normal range and were considered reversible during the 28-day recovery period. No macroscopic findings were reported, and histopathological changes related to HempChoice® Hemp Oil Extract exposure were limited to adaptive changes in the liver which were not observed in the recovery group animals. The no observed adverse effect level (NOAEL) for HempChoice® Hemp Oil Extract was determined to be 185.90 mg/kg BW/day in male and female Sprague-Dawley rats.
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Affiliation(s)
- Margitta Dziwenka
- GRAS Associates Nutrasource Pharmaceutical and Nutraceutical Services, 120 Research Lane, Suite 101, Guelph, Ontario, Canada, N1G 0B4
| | - Robert Coppock
- Toxicologist and Associates Ltd., PO Box 2031, Vegreville, AB T9C 1T2, Canada
| | - Michael H. Davidson
- Geocann, Innovation, Technology, & Clinical Research Dept., 320 E Vine Drive, Suite 207, Fort Collins, CO, 80524, USA
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Henderson RG, Welsh BT, Rogers JM, Borghoff SJ, Trexler KR, Bonn-Miller MO, Lefever TW. Reproductive and developmental toxicity evaluation of cannabidiol. Food Chem Toxicol 2023; 176:113786. [PMID: 37105390 DOI: 10.1016/j.fct.2023.113786] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023]
Abstract
An important data gap in determining a safe level of cannabidiol (CBD) intake for consumer use is determination of CBD's potential to cause reproductive or developmental toxicity. We conducted an OECD Test Guideline 421 GLP-compliant study in rats, with extended postnatal dosing and hormone analysis, where hemp-derived CBD isolate (0, 30, 100, or 300 mg/kg-bw/d) was administered orally. Treatment-related mortality, moribundity, and decreased body weight and food consumption were observed in high-dose F0 adult animals, consistent with severe maternal toxicity. No effects were observed on testosterone concentrations, F0 reproductive performance, or reproductive organs. Hepatocellular hypertrophy in the 100- and 300 mg/kg-bw/day groups correlated with hypertrophy/hyperplasia in the thyroid gland and changes in mean thyroid hormone concentrations in F0 animals. Mean gestation length was unaffected; however, total litter loss for two females and dystocia for two additional females in the high-dose group occurred. Other developmental effects were limited to lower mean pup weights in the 300 mg/kg-bw/d group than those of controls. The following NOAELs were identified for CBD isolate based on this study: 100 mg/kg-bw/d for F0 systemic toxicity and female reproductive toxicity, 300 mg/kg-bw/d for F0 male reproductive toxicity, and 100 mg/kg-bw/d for F1 neonatal and F1 generation toxicity.
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Affiliation(s)
| | | | - John M Rogers
- ToxStrategies, Inc., Research Triangle Park, NC, 27511, USA
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7
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Kluxen FM, Weber K, Strupp C, Jensen SM, Hothorn LA, Garcin JC, Hofmann T. Using historical control data in bioassays for regulatory toxicology. Regul Toxicol Pharmacol 2021; 125:105024. [PMID: 34364928 DOI: 10.1016/j.yrtph.2021.105024] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/21/2021] [Accepted: 07/30/2021] [Indexed: 12/12/2022]
Abstract
Historical control data (HCD) consist of pooled control group responses from bioassays. These data must be collected and are often used or reported in regulatory toxicology studies for multiple purposes: as quality assurance for the test system, to help identify toxicological effects and their effect-size relevance and to address the statistical multiple comparison problem. The current manuscript reviews the various classical and potential new approaches for using HCD. Issues in current practice are identified and recommendations for improved use and discussion are provided. Furthermore, stakeholders are invited to discuss whether it is necessary to consider uncertainty when using HCD formally and statistically in toxicological discussions and whether binary inclusion/exclusion criteria for HCD should be revised to a tiered information contribution to assessments. Overall, the critical value of HCD in toxicological bioassays is highlighted when used in a weight-of-evidence assessment.
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Affiliation(s)
| | | | | | - Signe M Jensen
- Department of Plant and Efoldnvironmental Sciences, University of Copenhagen, Copenhagen, Denmark
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8
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Murugan S, Solanki H, Purusothaman D, Bethapudi B, Ravalji M, Mundkinajeddu D. Safety Evaluation of Standardized Extract of Curcuma longa (NR-INF-02): A 90-Day Subchronic Oral Toxicity Study in Rats. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6671853. [PMID: 34337042 PMCID: PMC8294958 DOI: 10.1155/2021/6671853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 06/19/2021] [Indexed: 11/18/2022]
Abstract
NR-INF-02 is a standardized extract containing turmerosaccharides from Curcuma longa that has anti-inflammatory, analgesic, and chondroprotective potential. In view of its potential uses, NR-INF-02 was evaluated for its safety in Wistar rats at an oral dose of 250, 500, and 1000 mg/kg in a 90-day repeated dose subchronic toxicity study. NR-INF-02 administered at 250, 500, and 1000 mg/kg for 90 days did not show any mortality or clinical signs of toxicity. Body weight gain, food consumption, ocular and neurological examination, and hematological, blood biochemical, hormone, and urine analysis revealed no evidence of toxicity of NR-INF-02 treatment in rats. Absolute and relative organ weights were comparable to control rats. The study did not reveal any major treatment related gross pathological and histopathological alterations in the tissues or organs examined. Thus, based on study observations, the no-observed adverse effect level (NOAEL) was found to be 1000 mg/kg body weight in albino Wistar rats.
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Affiliation(s)
- Sasikumar Murugan
- R&D Center, Natural Remedies Private Limited, Bengaluru, Karnataka, India
| | | | - Divya Purusothaman
- R&D Center, Natural Remedies Private Limited, Bengaluru, Karnataka, India
| | - Bharathi Bethapudi
- R&D Center, Natural Remedies Private Limited, Bengaluru, Karnataka, India
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9
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Marty S, Beekhuijzen M, Charlton A, Hallmark N, Hannas BR, Jacobi S, Melching-Kollmuss S, Sauer UG, Sheets LP, Strauss V, Urbisch D, Botham PA, van Ravenzwaay B. Towards a science-based testing strategy to identify maternal thyroid hormone imbalance and neurodevelopmental effects in the progeny - part II: how can key events of relevant adverse outcome pathways be addressed in toxicological assessments? Crit Rev Toxicol 2021; 51:328-358. [PMID: 34074207 DOI: 10.1080/10408444.2021.1910625] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The current understanding of thyroid-related adverse outcome pathways (AOPs) with adverse neurodevelopmental outcomes in mammals has been reviewed. This served to establish if standard rodent toxicity test methods and in vitro assays allow identifying thyroid-related modes-of-action potentially leading to adverse neurodevelopmental outcomes, and the human relevance of effects - in line with the European Commission's Endocrine Disruptor Criteria. The underlying hypothesis is that an understanding of the key events of relevant AOPs provides insight into differences in incidence, magnitude, or species sensitivity of adverse outcomes. The rodent studies include measurements of serum thyroid hormones, thyroid gland pathology and neurodevelopmental assessments, but do not directly inform on specific modes-of-action. Opportunities to address additional non-routine parameters reflecting critical events of AOPs in toxicological assessments are presented. These parameters appear relevant to support the identification of specific thyroid-related modes-of-action, provided that prevailing technical limitations are overcome. Current understanding of quantitative key event relationships is often weak, but would be needed to determine if the triggering of a molecular initiating event will ultimately result in an adverse outcome. Also, significant species differences in all processes related to thyroid hormone signalling are evident, but the biological implications thereof (including human relevance) are often unknown. In conclusion, careful consideration of the measurement (e.g. timing, method) and interpretation of additional non-routine parameters is warranted. These findings will be used in a subsequent paper to propose a testing strategy to identify if a substance may elicit maternal thyroid hormone imbalance and potentially also neurodevelopmental effects in the progeny.
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Affiliation(s)
- Sue Marty
- The Dow Chemical Company, Midland, MI, USA
| | | | | | | | | | | | | | - Ursula G Sauer
- Scientific Consultancy - Animal Welfare, Neubiberg, Germany
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10
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Wheeler JR, Gao Z, Lagadic L, Salinas ER, Weltje L, Burden N. Hormone data collection in support of endocrine disruption (ED) assessment for aquatic vertebrates: Pragmatic and animal welfare considerations. ENVIRONMENT INTERNATIONAL 2021; 146:106287. [PMID: 33276311 DOI: 10.1016/j.envint.2020.106287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/19/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Affiliation(s)
- James R Wheeler
- Shell International B.V., Shell Health, Carel van Bylandtlaan 16, 2596 HR The Hague, the Netherlands.
| | - Zhenglei Gao
- Bayer AG Research and Development, Crop Science, Environmental Safety, Environmental Effects, Alfred-Nobel-Straße 50, 40789 Monheim am Rhein, Germany.
| | - Laurent Lagadic
- Bayer AG Research and Development, Crop Science, Environmental Safety, Environmental Effects, Alfred-Nobel-Straße 50, 40789 Monheim am Rhein, Germany.
| | - Edward R Salinas
- BASF SE, Agricultural Solutions - Ecotoxicology, Speyerer Strasse 2, 67117 Limburgerhof, Germany.
| | - Lennart Weltje
- BASF SE, Agricultural Solutions - Ecotoxicology, Speyerer Strasse 2, 67117 Limburgerhof, Germany.
| | - Natalie Burden
- NC3Rs, Gibbs Building, 215 Euston Road, London NW1 2BE, UK.
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11
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Phipps KR, Danielewska-Nikiel B, Mushonganono J, Baldwin N. Reproductive and developmental toxicity screening study of an acetone extract of rosemary. Regul Toxicol Pharmacol 2020; 120:104840. [PMID: 33321148 DOI: 10.1016/j.yrtph.2020.104840] [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] [Received: 08/11/2020] [Revised: 11/13/2020] [Accepted: 12/09/2020] [Indexed: 02/07/2023]
Abstract
In 2017, JECFA requested reproductive and developmental toxicity studies to finalize an acceptable daily intake for solvent rosemary extracts. Thus, an OECD 421 reproductive/developmental toxicity study was conducted using an acetone rosemary extract that complied with JECFA and EFSA food additive specifications. Rosemary extract was provided to rats at dietary concentrations of 0 (control), 2100, 3600, or 5000 mg/kg, for 14 days before mating, during mating, and thereafter (throughout gestation and up to Lactation Day 13 for females) until necropsy. General toxicity (clinical signs, body weight, food consumption) and reproductive/developmental outcomes (fertility and mating performance, estrous cycles, anogenital distance, thyroid hormones, reproductive organ weights, thyroid histopathology) were assessed. There were no signs of general toxicity and no effects on reproduction; thus, the highest concentration tested (equivalent to mean daily intakes of 316 or 401 mg/kg bw/day [149 or 189 mg/kg bw/day carnosol and carnosic acid] for males and females, respectively) was established as the no-observed-adverse-effect level for general and reproductive toxicity. Dose-related reductions in T4 were observed for Day 13 pups (not seen on Day 4) but were not accompanied by thyroid weight changes or histopathological findings; further investigations are required to determine the biological relevance of these T4 reductions.
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Affiliation(s)
- Kirt R Phipps
- Intertek Health Sciences Inc, Room 1036, Building A8, Cody Technology Park, Ively Road, Farnborough, Hampshire, UK.
| | | | - Jessica Mushonganono
- Intertek Health Sciences Inc, 2233 Argentia Road, Suite 201, Mississauga, Ontario, Canada
| | - Nigel Baldwin
- Intertek Health Sciences Inc, Room 1036, Building A8, Cody Technology Park, Ively Road, Farnborough, Hampshire, UK
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12
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Vandenberg LN, Prins GS, Patisaul HB, Zoeller RT. The Use and Misuse of Historical Controls in Regulatory Toxicology: Lessons from the CLARITY-BPA Study. Endocrinology 2020; 161:5613539. [PMID: 31690949 PMCID: PMC7182062 DOI: 10.1210/endocr/bqz014] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/04/2019] [Indexed: 12/14/2022]
Abstract
For many endocrine-disrupting chemicals (EDCs) including Bisphenol A (BPA), animal studies show that environmentally relevant exposures cause harm; human studies are consistent with these findings. Yet, regulatory agencies charged with protecting public health continue to conclude that human exposures to these EDCs pose no risk. One reason for the disconnect between the scientific consensus on EDCs in the endocrinology community and the failure to act in the regulatory community is the dependence of the latter on so-called "guideline studies" to evaluate hazards, and the inability to incorporate independent scientific studies in risk assessment. The Consortium Linking Academic and Regulatory Insights on Toxicity (CLARITY) study was intended to bridge this gap, combining a "guideline" study with independent hypothesis-driven studies designed to be more appropriate to evaluate EDCs. Here we examined an aspect of "guideline" studies, the use of so-called "historical controls," which are essentially control data borrowed from prior studies to aid in the interpretation of current findings. The US Food and Drug Administration authors used historical controls to question the plausibility of statistically significant BPA-related effects in the CLARITY study. We examined the use of historical controls on 5 outcomes in the CLARITY "guideline" study: mammary neoplasms, pituitary neoplasms, kidney nephropathy, prostate inflammation and adenomas, and body weight. Using US Food and Drug Administration-proposed historical control data, our evaluation revealed that endpoints used in "guideline" studies are not as reproducible as previously held. Combined with other data comparing the effects of ethinyl estradiol in 2 "guideline" studies including CLARITY-BPA, we conclude that near-exclusive reliance on "guideline" studies can result in scientifically invalid conclusions.
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Affiliation(s)
- Laura N Vandenberg
- Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts–Amherst, Amherst, Massachusetts
- Correspondence: Laura N. Vandenberg, PhD, Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts–Amherst, 171C Goessmann, 686 North Pleasant Street, Amherst, Massachusetts 01003. E-mail:
| | - Gail S Prins
- Department of Urology, School of Medicine; Division of Epidemiology & Biostatistics, School of Public Health University of Illinois at Chicago, Chicago, Illinois
| | - Heather B Patisaul
- Center for Human Health and the Environment, Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina
| | - R Thomas Zoeller
- Department of Biology, University of Massachusetts–Amherst, Amherst, Massachusetts
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