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Mirazi N, Amini E, Hosseini A, Izadi Z, Nourian A. Maternal long-term inhalation exposure to perchloroethylene and prenatal teratogenicity: morphometric, hormonal, and histological study. Toxicol Mech Methods 2023; 33:206-214. [PMID: 35941716 DOI: 10.1080/15376516.2022.2111675] [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: 10/15/2022]
Abstract
Some commonly used chemicals have teratogenic effects. Perchloroethylene (PCE) is a liquid that is widely used in various industries and drying clothes. In this study, the teratogenic effects of PCE in rat embryos were investigated. In this experimental study, 32 adult Wistar female rats in the weight range of 230-250 g were used. Female rats were randomly divided into 4 groups (n = 8). Control group (without PCE inhalation), experimental group G(I) (exposed to PCE 18 days prior to mating), experimental group G(II) (exposed to PCE 18 days after mating) and experimental group G(III) (exposed to PCE 18 days before and 18 days after mating). Pregnant rats were anesthetized on the 18th day of gestation and then serum and embryos were removed for the required studies. Embryos were examined for number, weight, sex, morphometric parameters of organs, and tissue samples were prepared for histological studies. Serum isolated from dams were evaluated for sexual and gonadal hormones. The results of this study showed that PCE has teratogenic effects on rat embryos. Infertility and reduced birth rate were other effects of PCE in rats. PCE has teratogenic effects and impairs the reproductive system of rats.
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Affiliation(s)
- Naser Mirazi
- Department of Biology, Faculty of Basic Sciences, Bu-Ali Sina University, Hamedan, Iran
| | - Elham Amini
- Department of Biology, Faculty of Basic Sciences, Bu-Ali Sina University, Hamedan, Iran
| | - Abdolkarim Hosseini
- Department of Animal Sciences and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran
| | - Zahra Izadi
- Department of Horticulture, Faculty of Agriculture, University of Nahavand, Nahavand, Iran
| | - Alireza Nourian
- Department of Pathobiology, Faculty of Veterinary Science, Bu-Ali Sina University, Hamedan, Iran
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Elkin ER, Su AL, Kilburn BA, Bakulski KM, Armant DR, Loch-Caruso R. Toxicity assessments of selected trichloroethylene and perchloroethylene metabolites in three in vitro human placental models. Reprod Toxicol 2022; 109:109-120. [PMID: 35304307 PMCID: PMC9107309 DOI: 10.1016/j.reprotox.2022.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 03/07/2022] [Accepted: 03/10/2022] [Indexed: 01/25/2023]
Abstract
Residential and occupational exposures to the industrial solvents perchloroethylene (PERC) and trichloroethylene (TCE) present public health concerns. In humans, maternal PERC and TCE exposures can be associated with adverse birth outcomes. Because PERC and TCE are biotransformed to toxic metabolites and placental dysfunction can contribute to adverse birth outcomes, the present study compared the toxicity of key PERC and TCE metabolites in three in vitro human placenta models. We measured cell viability and caspase 3 + 7 activity in the HTR-8/SVneo and BeWo cell lines, and caspase 3 + 7 activity in first trimester villous explant cultures. Cultures were exposed for 24 h to 5-100 µM S-(1,2-dichlorovinyl)-L-cysteine (DCVC) and S-(1,2,2-trichlorovinyl)-L-cysteine (TCVC), or 5-200 µM trichloroacetate (TCA) and dichloroacetate (DCA). DCVC significantly reduced cell viability and increased caspase 3 + 7 activity in HTR-8/SVneo cells at a lower concentration (20 µM) compared with concentrations toxic to BeWo cells and villous explants. Similarly, TCVC reduced cell viability and increased caspase 3 + 7 activity in HTR-8/SVneo cells but not in BeWo cells. TCA and DCA had only negligible effects on HTR-8/SVneo or BeWo cells. This study advances understanding of potential risks of PERC and TCE exposure during pregnancy by identifying metabolites toxic in placental cells and tissues.
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Affiliation(s)
- Elana R Elkin
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan, USA; Department of Nutritional Sciences, University of Michigan, Ann Arbor, Michigan, USA.
| | - Anthony L Su
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan, USA; Department of Nutritional Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Brian A Kilburn
- Department of Nutritional Sciences, University of Michigan, Ann Arbor, Michigan, USA; Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Kelly M Bakulski
- Department of Epidemiology, University of Michigan, Ann Arbor, Michigan, USA; Department of Nutritional Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - D Randall Armant
- Department of Nutritional Sciences, University of Michigan, Ann Arbor, Michigan, USA; Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, Michigan, USA; Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Rita Loch-Caruso
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan, USA
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3
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Liu Z, Wang M, Yu P, Li X, Lin Y, Duan Y, Tian Y, Zhu J, Deng Y, Li N. Maternal trichloroethylene exposure and metabolic gene polymorphisms may interact during fetal cardiovascular malformation. Reprod Toxicol 2021; 106:1-8. [PMID: 34555461 DOI: 10.1016/j.reprotox.2021.09.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 09/09/2021] [Accepted: 09/16/2021] [Indexed: 10/20/2022]
Abstract
This study aimed to analyze the potential association between trichloroethylene (TCE) exposure and congenital heart disease (CHD) and to explore the effect of metabolic enzyme gene polymorphisms on heart development. A multicenter case-control study was conducted. The trichloroethylene concentrations were measured by UPLC-MSMS in urine. Fourteen SNPs in the GSTA1, GSTP1, MPO, NAT1, NAT2, CYP1A1, CYP1A2, CYP2E1 and EPHX1 genes were genotyped using an improved multiplex ligation detection reaction (iMLDR) technique. A total of 283 cases and 331 controls with maternal urine and/or venous blood were included in the present study. The median NAcDCVC was 7.65 ng/mL in the case group and 7.43 ng/mL in the control group. There was no significant difference in the NAcDCVC concentration between the CHD subtypes and controls (P > 0.05). The GA/AA of GSTA1 rs3957357 could increase the risk of CHDs under the dominant model (aOR = 2.26, 95 % CI: 1.31, 3.90), but other SNPs were not associated with CHDs (P > 0.05). GA or AA genotypes of GSTA1 rs3957357 with lower levels of TCE exposure were 3.53 times at risk relative to mothers carrying the wild type genotype. In conclusion, maternal exposure to trichloroethylene alone is not associated with the occurrence of fetal CHD and CHD subtypes. Maternal GSTA1 rs3957357 may increase the risk of CHD in offspring. TCE exposure and metabolic gene polymorphisms probably interact with each other to induce fetal cardiovascular malformation, but larger sample size studies are needed to confirm this hypothesis.
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Affiliation(s)
- Zhen Liu
- National Center for Birth Defect Monitoring, Department of Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China; Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China
| | - Meixian Wang
- National Center for Birth Defect Monitoring, Department of Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China; Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China
| | - Ping Yu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China; Development and Related Diseases of Women and Children Key Laboratory of Sichuan Province, Chengdu, Sichuan, China
| | - Xiaohong Li
- National Center for Birth Defect Monitoring, Department of Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yuan Lin
- Department of Obstetrics & Gynecology, Fujian Provincial Maternal and Child Health Care Hospital, Fuzhou, Fujian, China
| | - Yinghong Duan
- Department of Obstetrics & Gynecology, Huize Maternal and Child Health Care Hospital, Qujing, Yunnan, China
| | - Yan Tian
- Department of Obstetrics & Gynecology, Maternal and Child Health Hospital of Liupanshui, Liupanshui, Guizhou, China
| | - Jun Zhu
- National Center for Birth Defect Monitoring, Department of Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China; Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China; Development and Related Diseases of Women and Children Key Laboratory of Sichuan Province, Chengdu, Sichuan, China
| | - Ying Deng
- National Center for Birth Defect Monitoring, Department of Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China; Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China.
| | - Nana Li
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, China; Development and Related Diseases of Women and Children Key Laboratory of Sichuan Province, Chengdu, Sichuan, China.
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DeSesso JM, Coder PS, York RG, Budinsky RA, Pottenger LH, Sen S, Lucarell JM, Bevan C, Bus JS. Trichloroethylene in drinking water throughout gestation did not produce congenital heart defects in Sprague Dawley rats. Birth Defects Res 2019; 111:1217-1233. [PMID: 31197966 PMCID: PMC7432160 DOI: 10.1002/bdr2.1531] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/23/2019] [Accepted: 05/09/2019] [Indexed: 02/05/2023]
Abstract
BACKGROUND Trichloroethylene (TCE) was negative for developmental toxicity after inhalation and oral gavage exposure of pregnant rats but fetal cardiac defects were reported following drinking water exposure throughout gestation. Because of the deficiencies in this latter study, we performed another drinking water study to evaluate whether TCE causes heart defects. METHODS Groups of 25 mated Sprague Dawley rats consumed water containing 0, 0.25, 1.5, 500, or 1,000 ppm TCE from gestational day 1-21. TCE concentrations were measured at daily formulation, when placed into water bottles each day and when water bottles were removed from cages. Four additional mated rats per group were used for plasma measurements. At termination, fetal hearts were carefully dissected fresh and examined. RESULTS All TCE concentrations were >90% of target when initially placed in water bottles and when bottles were placed on cages. All dams survived with no clinical signs. Rats in the two higher dose groups consumed less water/day than other groups but showed no changes in maternal or fetal weights. The only fetal cardiac observation was small (<1 mm) membranous ventricular septal defect occurring in all treated and water control groups; incidences were within the range of published findings for naive animals. TCE was not detected in maternal blood, but systemic exposure was confirmed by detecting its primary oxidative metabolite, trichloroacetic acid, although only at levels above the quantitation limit in the two higher dose groups. CONCLUSIONS Ingesting TCE in drinking water ≤1,000 ppm throughout gestation does not cause cardiac defects in rat offspring.
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Affiliation(s)
- John M. DeSesso
- ExponentAlexandriaVirginia
- Georgetown University School of MedicineWashingtonDistrict of Columbia
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5
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DeSesso JM, Coder PS, York RG, Budinsky RA, Pottenger LH, Sen S, Lucarell JM, Bevan C, Bus JS. Response to the comments of Runyan et al. on "Trichloroethylene in drinking water throughout gestation did not produce congenital heart defects in Sprague Dawley rats". Birth Defects Res 2019; 111:1237-1239. [PMID: 31419071 DOI: 10.1002/bdr2.1577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 07/27/2019] [Indexed: 11/10/2022]
Affiliation(s)
- John M DeSesso
- Exponent, Alexandria, Virginia.,Georgetown University School of Medicine, Washington, DC
| | | | | | | | - Lynn H Pottenger
- Olin Corporation, Midland, Michigan.,LHP Tox Consult, LLC, Midland, Michigan
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Arts J, Kellert M, Pottenger L, Theuns-van Vliet J. Evaluation of developmental toxicity of Methyl Chloride (Chloromethane) in rats, mice, and rabbits. Regul Toxicol Pharmacol 2019; 103:274-281. [DOI: 10.1016/j.yrtph.2019.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/04/2019] [Indexed: 11/26/2022]
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7
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Bolden AL, Schultz K, Pelch KE, Kwiatkowski CF. Exploring the endocrine activity of air pollutants associated with unconventional oil and gas extraction. Environ Health 2018; 17:26. [PMID: 29558955 PMCID: PMC5861625 DOI: 10.1186/s12940-018-0368-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 02/20/2018] [Indexed: 05/17/2023]
Abstract
BACKGROUND In the last decade unconventional oil and gas (UOG) extraction has rapidly proliferated throughout the United States (US) and the world. This occurred largely because of the development of directional drilling and hydraulic fracturing which allows access to fossil fuels from geologic formations that were previously not cost effective to pursue. This process is known to use greater than 1,000 chemicals such as solvents, surfactants, detergents, and biocides. In addition, a complex mixture of chemicals, including heavy metals, naturally-occurring radioactive chemicals, and organic compounds are released from the formations and can enter air and water. Compounds associated with UOG activity have been linked to adverse reproductive and developmental outcomes in humans and laboratory animal models, which is possibly due to the presence of endocrine active chemicals. METHODS Using systematic methods, electronic searches of PubMed and Web of Science were conducted to identify studies that measured chemicals in air near sites of UOG activity. Records were screened by title and abstract, relevant articles then underwent full text review, and data were extracted from the studies. A list of chemicals detected near UOG sites was generated. Then, the potential endocrine activity of the most frequently detected chemicals was explored via searches of literature from PubMed. RESULTS Evaluation of 48 studies that sampled air near sites of UOG activity identified 106 chemicals detected in two or more studies. Ethane, benzene and n-pentane were the top three most frequently detected. Twenty-one chemicals have been shown to have endocrine activity including estrogenic and androgenic activity and the ability to alter steroidogenesis. Literature also suggested that some of the air pollutants may affect reproduction, development, and neurophysiological function, all endpoints which can be modulated by hormones. These chemicals included aromatics (i.e., benzene, toluene, ethylbenzene, and xylene), several polycyclic aromatic hydrocarbons, and mercury. CONCLUSION These results provide a basis for prioritizing future primary studies regarding the endocrine disrupting properties of UOG air pollutants, including exposure research in wildlife and humans. Further, we recommend systematic reviews of the health impacts of exposure to specific chemicals, and comprehensive environmental sampling of a broader array of chemicals.
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Affiliation(s)
- Ashley L. Bolden
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
| | - Kim Schultz
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
| | - Katherine E. Pelch
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
| | - Carol F. Kwiatkowski
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado USA
- Biological Sciences, North Carolina State University, Raleigh, North Carolina USA
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8
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Wikoff D, Urban JD, Harvey S, Haws LC. Role of Risk of Bias in Systematic Review for Chemical Risk Assessment: A Case Study in Understanding the Relationship Between Congenital Heart Defects and Exposures to Trichloroethylene. Int J Toxicol 2018; 37:125-143. [PMID: 29357719 PMCID: PMC5888777 DOI: 10.1177/1091581818754330] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The National Academy of Science has recommended that a risk of bias (RoB; credibility of the link between exposure and outcome) assessment be conducted on studies that are used as primary data sources for hazard identification and dose-response assessment. Few applications of such have been conducted. Using trichloroethylene and congenital heart defects (CHDs) as a case study, we explore the role of RoB in chemical risk assessment using the National Toxicology Program's Office of Health Assessment and Translation RoB tool. Selected questions were tailored to evaluation of CHD and then applied to 12 experimental animal studies and 9 epidemiological studies. Results demonstrated that the inconsistent findings of a single animal study were likely explained by the limitations in study design assessed via RoB (eg, lack of concurrent controls, unvalidated method for assessing outcome, unreliable statistical methods, etc). Such limitations considered in the context of the body of evidence render the study not sufficiently reliable for the development of toxicity reference values. The case study highlights the utility of RoB as part of a robust risk assessment process and specifically demonstrates the role RoB can play in objectively selecting candidate data sets to develop toxicity values.
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9
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Harris AP, Ismail KA, Nunez M, Martopullo I, Lencinas A, Selmin OI, Runyan RB. Trichloroethylene perturbs HNF4a expression and activity in the developing chick heart. Toxicol Lett 2018; 285:113-120. [PMID: 29306027 DOI: 10.1016/j.toxlet.2017.12.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 12/23/2017] [Accepted: 12/29/2017] [Indexed: 12/11/2022]
Abstract
Exposure to trichloroethylene (TCE) is linked to formation of congenital heart defects in humans and animals. Prior interactome analysis identified the transcription factor, Hepatocyte Nuclear Factor 4 alpha (HNF4a), as a potential target of TCE exposure. As a role for HNF4a is unknown in the heart, we examined developing avian hearts for HNF4a expression and for sensitivity to TCE and the HNF4a agonist, Benfluorex. In vitro analysis using a HNF4a reporter construct showed both TCE and HFN4a to be antagonists of HNF4a-mediated transcription at the concentrations tested. HNF4a mRNA is expressed transiently in the embryonic heart during valve formation and cardiac development. Embryos were examined for altered gene expression in the presence of TCE or Benfluorex. TCE altered expression of selected mRNAs including HNF4a, TRAF6 and CYP2C45. There was a transition between inhibition and induction of marker gene expression in embryos as TCE concentration increased. Benfluorex was largely inhibitory to selected markers. Echocardiography of exposed embryos showed reduced cardiac function with both TCE and Benfluorex. Cardiac contraction was reduced by 29% and 23%, respectively at 10 ppb. The effects of TCE and Benfluorex on autocrine regulation of HNF4a, selected markers and cardiac function argue for a functional interaction of TCE and HNF4a. Further, the dose-sensitive shift between inhibition and induction of marker expression may explain the nonmonotonic-like dose response observed with TCE exposure in the heart.
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Affiliation(s)
- Alondra P Harris
- Department of Cellular & Molecular Medicine, University of Arizona, Tucson, AZ 85724-5044, United States
| | - Kareem A Ismail
- Department of Cellular & Molecular Medicine, University of Arizona, Tucson, AZ 85724-5044, United States
| | - Martha Nunez
- Department of Cellular & Molecular Medicine, University of Arizona, Tucson, AZ 85724-5044, United States
| | - Ira Martopullo
- Department of Cellular & Molecular Medicine, University of Arizona, Tucson, AZ 85724-5044, United States
| | - Alejandro Lencinas
- Department of Cellular & Molecular Medicine, University of Arizona, Tucson, AZ 85724-5044, United States
| | - Ornella I Selmin
- Department of Nutritional Sciences, University of Arizona, Tucson, AZ 85724-5044, United States
| | - Raymond B Runyan
- Department of Cellular & Molecular Medicine, University of Arizona, Tucson, AZ 85724-5044, United States.
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10
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Elkin ER, Harris SM, Loch-Caruso R. Trichloroethylene metabolite S-(1,2-dichlorovinyl)-l-cysteine induces lipid peroxidation-associated apoptosis via the intrinsic and extrinsic apoptosis pathways in a first-trimester placental cell line. Toxicol Appl Pharmacol 2018; 338:30-42. [PMID: 29129777 PMCID: PMC5741094 DOI: 10.1016/j.taap.2017.11.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 11/07/2017] [Accepted: 11/08/2017] [Indexed: 12/31/2022]
Abstract
Trichloroethylene (TCE), a prevalent environmental contaminant, is a potent renal and hepatic toxicant through metabolites such as S-(1, 2-dichlorovinyl)-l-cysteine (DCVC). However, effects of TCE on other target organs such as the placenta have been minimally explored. Because elevated apoptosis and lipid peroxidation in placenta have been observed in pregnancy morbidities involving poor placentation, we evaluated the effects of DCVC exposure on apoptosis and lipid peroxidation in a human extravillous trophoblast cell line, HTR-8/SVneo. We exposed the cells in vitro to 10-100μM DCVC for various time points up to 24h. Following exposure, we measured apoptosis using flow cytometry, caspase activity using luminescence assays, gene expression using qRT-PCR, and lipid peroxidation using a malondialdehyde quantification assay. DCVC significantly increased apoptosis in time- and concentration-dependent manners (p<0.05). DCVC also significantly stimulated caspase 3, 7, 8 and 9 activities after 12h (p<0.05), suggesting that DCVC stimulates the activation of both the intrinsic and extrinsic apoptotic signaling pathways simultaneously. Pre-treatment with the tBID inhibitor Bl-6C9 partially reduced DCVC-stimulated caspase 3 and 7 activity, signifying crosstalk between the two pathways. Additionally, DCVC treatment increased lipid peroxidation in a concentration-dependent manner. Co-treatment with the antioxidant peroxyl radical scavenger (±)-α-tocopherol attenuated caspase 3 and 7 activity, suggesting that lipid peroxidation mediates DCVC-induced apoptosis in extravillous trophoblasts. Our findings suggest that DCVC-induced apoptosis and lipid peroxidation in extravillous trophoblasts could contribute to poor placentation if similar effects occur in vivo in response to TCE exposure, indicating that further studies into this mechanism are warranted.
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Affiliation(s)
- Elana R Elkin
- Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
| | - Sean M Harris
- Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
| | - Rita Loch-Caruso
- Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
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11
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DeSesso JM, Risotto SP. Review of TCE cardiac defects data by Makris et al. is not systematic. Reprod Toxicol 2017; 71:134. [PMID: 28577896 DOI: 10.1016/j.reprotox.2017.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/25/2017] [Indexed: 11/26/2022]
Affiliation(s)
- John M DeSesso
- Center for Health Sciences, Exponent, 1800 Diagonal Road, Suite 500, Alexandria, Virginia 22314, United States; Department of Biochemistry and Molecular & Cellular Biology Georgetown University School of Medicine Washington DC 20057, United States.
| | - Stephen P Risotto
- Chemical Products & Technology Division, American Chemistry Council, Washington DC, 20002, United States
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12
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Makris SL. The systematic review of TCE cardiac defects (Makris et al., 2016). Reprod Toxicol 2017; 71:124-125. [PMID: 28571977 DOI: 10.1016/j.reprotox.2017.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 05/25/2017] [Indexed: 11/17/2022]
Affiliation(s)
- Susan L Makris
- U.S. Environmental Protection Agency, Office of Research and Development, National Center for Environmental Assessment, 1200 Pennsylvania Avenue, NW (MC 8623P), Washington, DC 20460, United States.
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13
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Makris SL, Scott CS, Fox J, Knudsen TB, Hotchkiss AK, Arzuaga X, Euling SY, Powers CM, Jinot J, Hogan KA, Abbott BD, Hunter ES, Narotsky MG. A systematic evaluation of the potential effects of trichloroethylene exposure on cardiac development. Reprod Toxicol 2016; 65:321-358. [PMID: 27575429 PMCID: PMC9113522 DOI: 10.1016/j.reprotox.2016.08.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 07/27/2016] [Accepted: 08/25/2016] [Indexed: 11/26/2022]
Abstract
The 2011 EPA trichloroethylene (TCE) IRIS assessment, used developmental cardiac defects from a controversial drinking water study in rats (Johnson et al. [51]), along with several other studies/endpoints to derive reference values. An updated literature search of TCE-related developmental cardiac defects was conducted. Study quality, strengths, and limitations were assessed. A putative adverse outcome pathway (AOP) construct was developed to explore key events for the most commonly observed cardiac dysmorphologies, particularly those involved with epithelial-mesenchymal transition (EMT) of endothelial origin (EndMT); several candidate pathways were identified. A hypothesis-driven weight-of-evidence analysis of epidemiological, toxicological, in vitro, in ovo, and mechanistic/AOP data concluded that TCE has the potential to cause cardiac defects in humans when exposure occurs at sufficient doses during a sensitive window of fetal development. The study by Johnson et al. [51] was reaffirmed as suitable for hazard characterization and reference value derivation, though acknowledging study limitations and uncertainties.
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14
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Wirbisky SE, Damayanti NP, Mahapatra CT, Sepúlveda MS, Irudayaraj J, Freeman JL. Mitochondrial Dysfunction, Disruption of F-Actin Polymerization, and Transcriptomic Alterations in Zebrafish Larvae Exposed to Trichloroethylene. Chem Res Toxicol 2016; 29:169-79. [PMID: 26745549 DOI: 10.1021/acs.chemrestox.5b00402] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Trichloroethylene (TCE) is primarily used as an industrial degreasing agent and has been in use since the 1940s. TCE is released into the soil, surface, and groundwater. From an environmental and regulatory standpoint, more than half of Superfund hazardous waste sites on the National Priority List are contaminated with TCE. Occupational exposure to TCE occurs primarily via inhalation, while environmental TCE exposure also occurs through ingestion of contaminated drinking water. Current literature links TCE exposure to various adverse health effects including cardiovascular toxicity. Current studies aiming to address developmental cardiovascular toxicity utilized rodent and avian models, with the majority of studies using relatively higher parts per million (mg/L) doses. In this study, to further investigate developmental cardiotoxicity of TCE, zebrafish embryos were treated with 0, 10, 100, or 500 parts per billion (ppb; μg/L) TCE during embryogenesis and/or through early larval stages. After the appropriate exposure period, angiogenesis, F-actin, and mitochondrial function were assessed. A significant dose-response decrease in angiogenesis, F-actin, and mitochondrial function was observed. To further complement this data, a transcriptomic profile of zebrafish larvae was completed to identify gene alterations associated with the 10 ppb TCE exposure. Results from the transcriptomic data revealed that embryonic TCE exposure caused significant changes in genes associated with cardiovascular disease, cancer, and organismal injury and abnormalities with a number of targets in the FAK signaling pathway. Overall, results from our study support TCE as a developmental cardiovascular toxicant, provide molecular targets and pathways for investigation in future studies, and indicate a need for continued priority for environmental regulation.
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Affiliation(s)
- Sara E Wirbisky
- School of Health Sciences, ‡Agricultural and Biological Engineering, §Department of Forestry and Natural Resources, ∥Purdue Center for Cancer Research, Purdue University , West Lafayette, Indiana 47907, United States
| | - Nur P Damayanti
- School of Health Sciences, ‡Agricultural and Biological Engineering, §Department of Forestry and Natural Resources, ∥Purdue Center for Cancer Research, Purdue University , West Lafayette, Indiana 47907, United States
| | - Cecon T Mahapatra
- School of Health Sciences, ‡Agricultural and Biological Engineering, §Department of Forestry and Natural Resources, ∥Purdue Center for Cancer Research, Purdue University , West Lafayette, Indiana 47907, United States
| | - Maria S Sepúlveda
- School of Health Sciences, ‡Agricultural and Biological Engineering, §Department of Forestry and Natural Resources, ∥Purdue Center for Cancer Research, Purdue University , West Lafayette, Indiana 47907, United States
| | - Joseph Irudayaraj
- School of Health Sciences, ‡Agricultural and Biological Engineering, §Department of Forestry and Natural Resources, ∥Purdue Center for Cancer Research, Purdue University , West Lafayette, Indiana 47907, United States
| | - Jennifer L Freeman
- School of Health Sciences, ‡Agricultural and Biological Engineering, §Department of Forestry and Natural Resources, ∥Purdue Center for Cancer Research, Purdue University , West Lafayette, Indiana 47907, United States
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15
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Swartz MD, Cai Y, Chan W, Symanski E, Mitchell LE, Danysh HE, Langlois PH, Lupo PJ. Air toxics and birth defects: a Bayesian hierarchical approach to evaluate multiple pollutants and spina bifida. Environ Health 2015; 14:16. [PMID: 25971584 PMCID: PMC4429479 DOI: 10.1186/1476-069x-14-16] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 01/29/2015] [Indexed: 05/28/2023]
Abstract
BACKGROUND While there is evidence that maternal exposure to benzene is associated with spina bifida in offspring, to our knowledge there have been no assessments to evaluate the role of multiple hazardous air pollutants (HAPs) simultaneously on the risk of this relatively common birth defect. In the current study, we evaluated the association between maternal exposure to HAPs identified by the United States Environmental Protection Agency (U.S. EPA) and spina bifida in offspring using hierarchical Bayesian modeling that includes Stochastic Search Variable Selection (SSVS). METHODS The Texas Birth Defects Registry provided data on spina bifida cases delivered between 1999 and 2004. The control group was a random sample of unaffected live births, frequency matched to cases on year of birth. Census tract-level estimates of annual HAP levels were obtained from the U.S. EPA's 1999 Assessment System for Population Exposure Nationwide. Using the distribution among controls, exposure was categorized as high exposure (>95(th) percentile), medium exposure (5(th)-95(th) percentile), and low exposure (<5(th) percentile, reference). We used hierarchical Bayesian logistic regression models with SSVS to evaluate the association between HAPs and spina bifida by computing an odds ratio (OR) for each HAP using the posterior mean, and a 95% credible interval (CI) using the 2.5(th) and 97.5(th) quantiles of the posterior samples. Based on previous assessments, any pollutant with a Bayes factor greater than 1 was selected for inclusion in a final model. RESULTS Twenty-five HAPs were selected in the final analysis to represent "bins" of highly correlated HAPs (ρ > 0.80). We identified two out of 25 HAPs with a Bayes factor greater than 1: quinoline (ORhigh = 2.06, 95% CI: 1.11-3.87, Bayes factor = 1.01) and trichloroethylene (ORmedium = 2.00, 95% CI: 1.14-3.61, Bayes factor = 3.79). CONCLUSIONS Overall there is evidence that quinoline and trichloroethylene may be significant contributors to the risk of spina bifida. Additionally, the use of Bayesian hierarchical models with SSVS is an alternative approach in the evaluation of multiple environmental pollutants on disease risk. This approach can be easily extended to environmental exposures, where novel approaches are needed in the context of multi-pollutant modeling.
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Affiliation(s)
- Michael D Swartz
- />Division of Biostatistics, University of Texas School of Public Health, Houston, TX USA
| | - Yi Cai
- />Division of Biostatistics, University of Texas School of Public Health, Houston, TX USA
| | - Wenyaw Chan
- />Division of Biostatistics, University of Texas School of Public Health, Houston, TX USA
| | - Elaine Symanski
- />Division of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health, Houston, TX USA
| | - Laura E Mitchell
- />Division of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health, Houston, TX USA
| | - Heather E Danysh
- />Department of Pediatrics, Section of Hematology-Oncology and Texas Children’s Cancer Center, Baylor College of Medicine, Houston, TX USA
| | - Peter H Langlois
- />Birth Defects Epidemiology and Surveillance Branch, Texas Department of State Health Services, Austin, TX USA
| | - Philip J Lupo
- />Department of Pediatrics, Section of Hematology-Oncology and Texas Children’s Cancer Center, Baylor College of Medicine, Houston, TX USA
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Brender JD, Shinde MU, Zhan FB, Gong X, Langlois PH. Maternal residential proximity to chlorinated solvent emissions and birth defects in offspring: a case-control study. Environ Health 2014; 13:96. [PMID: 25406847 PMCID: PMC4247650 DOI: 10.1186/1476-069x-13-96] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 11/05/2014] [Indexed: 05/10/2023]
Abstract
BACKGROUND Some studies have noted an association between maternal occupational exposures to chlorinated solvents and birth defects in offspring, but data are lacking on the potential impact of industrial air emissions of these solvents on birth defects. METHODS With data from the Texas Birth Defects Registry for births occurring in 1996-2008, we examined the relation between maternal residential proximity to industrial air releases of chlorinated solvents and birth defects in offspring of 60,613 case-mothers and 244,927 control-mothers. Maternal residential exposures to solvent emissions were estimated with metrics that took into account residential distances to industrial sources and annual amounts of chemicals released. Logistic regression was used to generate odds ratios and 95% confidence intervals for the associations between residential proximity to emissions of 14 chlorinated solvents and selected birth defects, including neural tube, oral cleft, limb deficiency, and congenital heart defects. All risk estimates were adjusted for year of delivery and maternal age, education, race/ethnicity, and public health region of residence. RESULTS Relative to exposure risk values of 0, neural tube defects were associated with maternal residential exposures (exposure risk values >0) to several types of chlorinated solvents, most notably carbon tetrachloride (adjusted odds ratio [aOR] 1.42, 95% confidence interval [CI] 1.09, 1.86); chloroform (aOR 1.40, 95% CI 1.04, 1.87); ethyl chloride (aOR 1.39, 95% CI 1.08, 1.79); 1,1,2-trichloroethane (aOR 1.56, 95% CI 1.11, 2.18); and 1,2,3-trichloropropane (aOR 1.49, 95% CI 1.08, 2.06). Significant associations were also noted between a few chlorinated solvents and oral cleft, limb deficiency, and congenital heart defects. We observed stronger associations between some emissions and neural tube, oral cleft, and heart defects in offspring of mothers 35 years or older, such as spina bifida with carbon tetrachloride (aOR 2.49, 95% CI 1.09, 5.72), cleft palate with 1,2-dichloroethane (aOR 1.93, 95% 1.05, 3.54), cleft lip with or without cleft palate with ethyl chloride (aOR 1.81, 95% CI 1.06, 3.07), and obstructive heart defects with trichloroethylene (aOR 1.43, 95% CI 1.08, 1.88). CONCLUSIONS These findings suggest that maternal residential proximity to industrial emissions of chlorinated solvents might be associated with selected birth defects in offspring, especially among older mothers.
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Affiliation(s)
- Jean D Brender
- />Department of Epidemiology & Biostatistics, Texas A&M Health Science Center School of Public Health, College Station, TX 77843-1266 USA
| | - Mayura U Shinde
- />Department of Epidemiology & Biostatistics, Texas A&M Health Science Center School of Public Health, College Station, TX 77843-1266 USA
| | - F Benjamin Zhan
- />Department of Geography, Texas Center for Geographic Information Science, Texas State University, San Marcos, TX 78666 USA
| | - Xi Gong
- />Department of Geography, Texas Center for Geographic Information Science, Texas State University, San Marcos, TX 78666 USA
| | - Peter H Langlois
- />Texas Department of State Health Services, Birth Defects Epidemiology and Surveillance Branch, MC 1964, PO Box 149347, Austin, TX 78714-9347 USA
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Chiu WA, Jinot J, Scott CS, Makris SL, Cooper GS, Dzubow RC, Bale AS, Evans MV, Guyton KZ, Keshava N, Lipscomb JC, Barone S, Fox JF, Gwinn MR, Schaum J, Caldwell JC. Human health effects of trichloroethylene: key findings and scientific issues. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:303-11. [PMID: 23249866 PMCID: PMC3621199 DOI: 10.1289/ehp.1205879] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 12/17/2012] [Indexed: 05/19/2023]
Abstract
BACKGROUND In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) completed a toxicological review of trichloroethylene (TCE) in September 2011, which was the result of an effort spanning > 20 years. OBJECTIVES We summarized the key findings and scientific issues regarding the human health effects of TCE in the U.S. EPA's toxicological review. METHODS In this assessment we synthesized and characterized thousands of epidemiologic, experimental animal, and mechanistic studies, and addressed several key scientific issues through modeling of TCE toxicokinetics, meta-analyses of epidemiologic studies, and analyses of mechanistic data. DISCUSSION Toxicokinetic modeling aided in characterizing the toxicological role of the complex metabolism and multiple metabolites of TCE. Meta-analyses of the epidemiologic data strongly supported the conclusions that TCE causes kidney cancer in humans and that TCE may also cause liver cancer and non-Hodgkin lymphoma. Mechanistic analyses support a key role for mutagenicity in TCE-induced kidney carcinogenicity. Recent evidence from studies in both humans and experimental animals point to the involvement of TCE exposure in autoimmune disease and hypersensitivity. Recent avian and in vitro mechanistic studies provided biological plausibility that TCE plays a role in developmental cardiac toxicity, the subject of substantial debate due to mixed results from epidemiologic and rodent studies. CONCLUSIONS TCE is carcinogenic to humans by all routes of exposure and poses a potential human health hazard for noncancer toxicity to the central nervous system, kidney, liver, immune system, male reproductive system, and the developing embryo/fetus.
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Affiliation(s)
- Weihsueh A Chiu
- National Center for Environmental Assessment, U.S. Environmental Protection Agency (EPA), Washington, DC, USA.
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18
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Brown Dzubow R, Makris S, Siegel Scott C, Barone S. Early lifestage exposure and potential developmental susceptibility to tetrachloroethylene. ACTA ACUST UNITED AC 2010; 89:50-65. [PMID: 20041493 DOI: 10.1002/bdrb.20222] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Tetrachloroethylene, also known as perchloroethylene or "perc", is a highly volatile and lipophilic solvent widely used in dry cleaning, textile processing, and metal-cleaning operations. The limited epidemiological and toxicological data available for exposure to perc during developmental lifestages, as well as the evidence for critical windows of exposure, highlight early life as a period of potential susceptibility. METHODS A literature search was performed to identify all peer-reviewed epidemiological and toxicologial studies examining outcomes from early lifestage exposure to perc, and reviewed by developmental stage for both exposure and outcome. RESULTS Exposure scenarios to perc unique to early lifestages include transplacental and breast milk intake, along with inhalation, ingestion, or dermal exposure. Toxicokinetics factors that may influence early lifestage susceptibility to perc, along with existing physiologically based pharmacokinetic (PBPK) models, are described. Adverse outcomes examined include: reproductive outcomes examined prior to conception including reduced fertility, adverse effects on sperm, or altered reproductive hormones; prenatal outcomes examined after exposure prior to conception or prenatally including fetal death, birth defects, and decreased birth weight; postnatal outcomes examined after exposure prior to conception, prenatally, or during childhood including neurotoxicity, immunotoxicity, cancer, hepatotoxicity, congential anomalies and mortality; and adult schizophrenia examined after exposure prior to conception. CONCLUSIONS The limited evidence on early lifestage exposure to perc does not provide sufficient evidence of this sensitive period as being more or less important than exposure at a later lifestage, such as during adulthood. However, there are a number of adverse health effects observed uniquely in early lifestages, and increased sensitivity to visual system deficits is suggested in children. Other outcomes observed in adults may not have been adequately assessed in children to directly compare sensitivity.
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Affiliation(s)
- Rebecca Brown Dzubow
- National Center for Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, Mailcode 8623-P, Washington, DC 20460, USA.
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Rufer ES, Hacker TA, Flentke GR, Drake VJ, Brody MJ, Lough J, Smith SM. Altered cardiac function and ventricular septal defect in avian embryos exposed to low-dose trichloroethylene. Toxicol Sci 2009; 113:444-52. [PMID: 19910388 DOI: 10.1093/toxsci/kfp269] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Trichloroethylene (TCE) is the most frequently reported organic groundwater contaminant in the United States. It is controversial whether gestational TCE exposure causes congenital heart defects. The basis for TCE's proposed cardiac teratogenicity is not well understood. We previously showed that chick embryos exposed to 8 ppb TCE during cardiac morphogenesis have reduced cardiac output and increased mortality. To further investigate TCE's cardioteratogenic potential, we exposed in ovo chick embryos to TCE and evaluated the heart thereafter. Significant mortality was observed following TCE exposures of 8-400 ppb during a narrow developmental period (Hamburger-Hamilton [HH] stages 15-20, embryo day ED2.3-3.5) that is characterized by myocardial expansion, secondary heart looping, and endocardial cushion formation. Of the embryos that died, most did so between ED5.5 and ED6.5. Echocardiography of embryos at ED5.5 found that TCE-exposed hearts displayed significant functional and morphological heterogeneity affecting heart rate, left ventricular mass, and wall thickness. Individual embryos were identified with cardiac hypertrophy as well as with hypoplasia. Chick embryos exposed to 8 ppb TCE at HH17 that survived to hatch exhibited a high incidence (38%, p < 0.01, n = 16) of muscular ventricular septal defects (VSDs) as detected by echocardiography and confirmed by gross dissection; no VSDs were found in controls (n = 14). The TCE-induced VSDs may be secondary to functional impairments that alter cardiac hemodynamics and subsequent ventricular foramen closure, an interpretation consistent with recent demonstrations that TCE impairs calcium handling in cardiomyocytes. These data demonstrate that TCE is a cardiac teratogen for chick.
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Affiliation(s)
- Echoleah S Rufer
- Molecular and Environmental Toxicology Center, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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Tabrez S, Ahmad M. Toxicity, biomarkers, genotoxicity, and carcinogenicity of trichloroethylene and its metabolites: a review. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, ENVIRONMENTAL CARCINOGENESIS & ECOTOXICOLOGY REVIEWS 2009; 27:178-196. [PMID: 19657920 DOI: 10.1080/10590500903091340] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Trichloroethylene (TCE) is a prevalent occupational and environmental contaminant that has been reported to cause a variety of toxic effects. This article reviews toxicity, mutagenicity, and carcinogenicity caused by the exposure of TCE and its metabolites in the living system as well as on their (TCE and its metabolites) toxicity biomarkers.
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Williams AL, DeSesso JM. Trichloroethylene and ocular malformations: analysis of extant literature. Int J Toxicol 2008; 27:81-95. [PMID: 18293215 DOI: 10.1080/10915810701876760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
An evaluation of the scientific literature for trichloroethylene (TCE) identified two reports of ocular defects, specifically microphthalmia/anophthalmia, following prenatal TCE exposure in rats. Herein, these reports are analyzed in detail and interpreted within the context of other developmental TCE exposure studies. The ocular findings following prenatal TCE exposure are reported in studies that were not designed specifically for developmental safety assessment, and thus did not use standard experimental practices. Furthermore, these findings most commonly occurred at TCE doses associated with considerable maternal toxicity. Among the 18 published studies using developmental TCE exposures, only 3 used doses sufficiently high enough to result in maternal toxicity, and of these, only the 2 discussed in detail in this paper demonstrated ocular defects in the offspring. Furthermore, statistically significant effects were only observed at doses that were above the currently accepted guideline limit dose of 1000 mg/kg body weight. All other TCE developmental exposure studies failed to demonstrate ocular defects as a result of prenatal exposure. These results suggest that the micro-/anophthalmia findings were likely a consequence of delivery of an extremely high bolus TCE dose that is irrelevant to human environmental exposure scenarios.
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