101
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Microbial colonization is required for normal neurobehavioral development in zebrafish. Sci Rep 2017; 7:11244. [PMID: 28894128 PMCID: PMC5593827 DOI: 10.1038/s41598-017-10517-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 08/10/2017] [Indexed: 12/18/2022] Open
Abstract
Changes in resident microbiota may have wide-ranging effects on human health. We investigated whether early life microbial disruption alters neurodevelopment and behavior in larval zebrafish. Conventionally colonized, axenic, and axenic larvae colonized at 1 day post fertilization (dpf) were evaluated using a standard locomotor assay. At 10 dpf, axenic zebrafish exhibited hyperactivity compared to conventionalized and conventionally colonized controls. Impairment of host colonization using antibiotics also caused hyperactivity in conventionally colonized larvae. To determine whether there is a developmental requirement for microbial colonization, axenic embryos were serially colonized on 1, 3, 6, or 9 dpf and evaluated on 10 dpf. Normal activity levels were observed in axenic larvae colonized on 1–6 dpf, but not on 9 dpf. Colonization of axenic embryos at 1 dpf with individual bacterial species Aeromonas veronii or Vibrio cholerae was sufficient to block locomotor hyperactivity at 10 dpf. Exposure to heat-killed bacteria or microbe-associated molecular patterns pam3CSK4 or Poly(I:C) was not sufficient to block hyperactivity in axenic larvae. These data show that microbial colonization during early life is required for normal neurobehavioral development and support the concept that antibiotics and other environmental chemicals may exert neurobehavioral effects via disruption of host-associated microbial communities.
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102
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Mora-Zamorano F, Klingler R, Basu N, Head J, Murphy CA, Binkowski FP, Larson JK, Carvan MJ. Developmental Methylmercury Exposure Affects Swimming Behavior and Foraging Efficiency of Yellow Perch ( Perca flavescens) Larvae. ACS OMEGA 2017; 2:4870-4877. [PMID: 28884165 PMCID: PMC5579541 DOI: 10.1021/acsomega.7b00227] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 07/25/2017] [Indexed: 05/20/2023]
Abstract
Methylmercury (MeHg) is a pervasive and ubiquitous environmental neurotoxicant within aquatic ecosystems, known to alter behavior in fish and other vertebrates. This study sought to assess the behavioral effects of developmental MeHg exposure on larval yellow perch (Perca flavescens)-a nonmodel fish species native to the Great Lakes. Embryos were exposed to MeHg (0, 30, 100, 300, and 1000 nM) for 20 h and then reared to 25 days post fertilization (dpf) for analyses of spontaneous swimming, visual motor response (VMR), and foraging efficiency. MeHg exposures rendered total mercury (THg) body burdens of 0.02, 0.21, 0.95, 3.14, and 14.93 μg/g (wet weight). Organisms exposed to 1000 nM exhibited high mortality; thus, they were excluded from downstream behavioral analyses. All MeHg exposures tested were associated with a reduction in spontaneous swimming at 17 and 25 dpf. Exposure to 30 and 100 nM MeHg caused altered locomotor output during the VMR assay at 21 dpf, whereas exposure to 100 nM MeHg was associated with decreased foraging efficiency at 25 dpf. For the sake of comparison, the second-lowest exposure tested here rendered a THg burden that represents the permissible level of consumable fish in the United States. Moreover, this dose is reported in roughly two-thirds of consumable fish species monitored in the United States, according to the Food and Drug Administration. Although the THg body burdens reported here were higher than expected in the environment, our study is the first to analyze the effects of MeHg exposure on fundamental survival behaviors of yellow perch larvae and advances in the exploration of the ecological relevance of behavioral end points.
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Affiliation(s)
- Francisco
X. Mora-Zamorano
- School
of Freshwater Sciences, University of Wisconsin
at Milwaukee, 600 E Greenfield
Avenue, Milwaukee, Wisconsin 53204, United States
| | - Rebekah Klingler
- School
of Freshwater Sciences, University of Wisconsin
at Milwaukee, 600 E Greenfield
Avenue, Milwaukee, Wisconsin 53204, United States
| | - Niladri Basu
- Department
of Natural Resource Sciences, McGill University, 845 Sherbrooke Street W, Sainte-Anne-de-Bellevue, Quebec H9X 3V9, Canada
| | - Jessica Head
- Department
of Natural Resource Sciences, McGill University, 845 Sherbrooke Street W, Sainte-Anne-de-Bellevue, Quebec H9X 3V9, Canada
| | - Cheryl A. Murphy
- Department
of Fisheries and Wildlife, Michigan State
University, 220 Trowbridge
Road, East Lansing, Michigan 48824, United States
| | - Frederick P. Binkowski
- School
of Freshwater Sciences, University of Wisconsin
at Milwaukee, 600 E Greenfield
Avenue, Milwaukee, Wisconsin 53204, United States
| | - Jeremy K. Larson
- School
of Freshwater Sciences, University of Wisconsin
at Milwaukee, 600 E Greenfield
Avenue, Milwaukee, Wisconsin 53204, United States
| | - Michael J. Carvan
- School
of Freshwater Sciences, University of Wisconsin
at Milwaukee, 600 E Greenfield
Avenue, Milwaukee, Wisconsin 53204, United States
- E-mail: . Tel: +1(414)-382-1700. Fax: +1(414)-382-1705
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103
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Frank CL, Brown JP, Wallace K, Mundy WR, Shafer TJ. From the Cover: Developmental Neurotoxicants Disrupt Activity in Cortical Networks on Microelectrode Arrays: Results of Screening 86 Compounds During Neural Network Formation. Toxicol Sci 2017; 160:121-135. [DOI: 10.1093/toxsci/kfx169] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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104
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Sethi S, Chen X, Kass PH, Puschner B. Polychlorinated biphenyl and polybrominated diphenyl ether profiles in serum from cattle, sheep, and goats across California. CHEMOSPHERE 2017; 181:63-73. [PMID: 28426942 PMCID: PMC5494844 DOI: 10.1016/j.chemosphere.2017.04.059] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/13/2017] [Accepted: 04/13/2017] [Indexed: 05/02/2023]
Abstract
It has been previously been shown by our lab and others that persistent organic pollutants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), are contaminants in milk produced for human consumption. To further this research we determined the concentration of 21 PCB and 14 PBDE congeners in livestock serum, mainly bovine, across California. Congeners were extracted from serum using solid phase extraction (SPE), cleaned up by silica cartridge and quantified using gas chromatography-triple quadruple mass spectrometry. We detected significant differences among species and the production class of cattle (beef or dairy). The sum of all 21 PCB congeners (ΣPCBs) in caprine and ovine sera had a mean value of 9.26 and 9.13 ng/mL, respectively, compared to 3.98 ng/mL in bovine sera. The mean value for the sum of all 14 PBDE congeners (ΣPBDEs) in caprine and ovine sera was 2.82 and 2.39 ng/mL, respectively, compared to 0.91 ng/mL in bovine sera. Mean ΣPCBs in dairy cattle was 5.92 ng/mL compared to 2.70 ng/mL in beef cattle. Mean ΣPBDEs in dairy cattle was 1.33 ng/mL compared to 0.70 ng/mL in beef cattle. There were no regional differences in the ΣPCBs or ΣPBDEs in cattle distributed across California. These results highlight the fact that livestock are still being exposed to these pollutants yet little is known about where this exposure may be coming from.
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Affiliation(s)
- S Sethi
- Department of Molecular Biosciences, University of California, Davis, CA, United States
| | - X Chen
- Department of Molecular Biosciences, University of California, Davis, CA, United States
| | - P H Kass
- Department of Population Health and Reproduction, University of California, Davis, CA, United States
| | - B Puschner
- Department of Molecular Biosciences, University of California, Davis, CA, United States.
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105
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Toxicant induced behavioural aberrations in larval zebrafish are dependent on minor methodological alterations. Toxicol Lett 2017; 276:62-68. [DOI: 10.1016/j.toxlet.2017.05.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 05/10/2017] [Accepted: 05/16/2017] [Indexed: 11/20/2022]
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106
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Dodson RE, Rodgers KM, Carey G, Cedeno Laurent JG, Covaci A, Poma G, Malarvannan G, Spengler JD, Rudel RA, Allen JG. Flame Retardant Chemicals in College Dormitories: Flammability Standards Influence Dust Concentrations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:4860-4869. [PMID: 28406624 DOI: 10.1021/acs.est.7b00429] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Furniture flammability standards are typically met with chemical flame retardants (FRs). FRs can migrate out of products into dust and are linked to cancer, neurological impairment, and endocrine disruption. We collected 95 dust samples from dormitory common areas and student rooms on two U.S. college campuses adhering to two different furniture flammability standards: Technical Bulletin 117 (TB117) and Technical Bulletin 133 (TB133). Because TB133 requires furniture to withstand a much-more-demanding test flame than TB117, we hypothesized that spaces with TB133 furniture would have higher levels of FRs in dust. We found all 47 targeted FRs, including 12 polybrominated diphenyl ether (PBDE) congeners, 19 other brominated FRs, 11 phosphorus FRs (PFRs), 2 Dechlorane-Plus (DP) isomers, and 3 hexabromocyclododecane (HBCDD) isomers in the 95 dust samples. We measured the highest reported U.S. concentrations for a number of FRs, including BDE 209 (up to 990 000 ng/g), which may be used to meet the TB133 standard. We prioritized 16 FRs and analyzed levels in relation to flammability standard as well as presence and age of furniture and electronics. Adherence to TB133 was associated with higher concentrations of BDE 209, decabromodiphenylethane (DBDPE), DPs, and HBCDD compared to adherence to TB117 in univariate models (p < 0.05). Student dormitory rooms tended to have higher levels of some FRs compared to common rooms, likely a result of the density of furniture and electronics. As flammability standards are updated, it is critical to understand their impact on exposure and health risks.
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Affiliation(s)
- Robin E Dodson
- Silent Spring Institute , 320 Nevada Street, Suite 302, Newton, Massachusetts 02460, United States
| | - Kathryn M Rodgers
- Silent Spring Institute , 320 Nevada Street, Suite 302, Newton, Massachusetts 02460, United States
| | - Gale Carey
- University of New Hampshire , Rudman Hall, 46 College Road, Durham, New Hampshire 03824, United States
| | | | - Adrian Covaci
- Toxicological Centre, University of Antwerp , Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium
| | - Giulia Poma
- Toxicological Centre, University of Antwerp , Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium
| | - Govindan Malarvannan
- Toxicological Centre, University of Antwerp , Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium
| | - John D Spengler
- Harvard T.H. Chan School of Public Health , 401 Park Drive, Boston, Massachusetts 02115, United States
| | - Ruthann A Rudel
- Silent Spring Institute , 320 Nevada Street, Suite 302, Newton, Massachusetts 02460, United States
| | - Joseph G Allen
- Harvard T.H. Chan School of Public Health , 401 Park Drive, Boston, Massachusetts 02115, United States
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107
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Glaberman S, Padilla S, Barron MG. Evaluating the zebrafish embryo toxicity test for pesticide hazard screening. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2017; 36:1221-1226. [PMID: 27699829 PMCID: PMC7737843 DOI: 10.1002/etc.3641] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/26/2016] [Accepted: 10/02/2016] [Indexed: 05/23/2023]
Abstract
Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictive of standard, more resource-intensive, juvenile fish acute toxicity tests. However, there is also evidence that fish embryos are less sensitive than juvenile fish for certain types of chemicals, including neurotoxicants. The utility of fish embryos for pesticide hazard assessment was investigated by comparing published zebrafish embryo toxicity data from pesticides with median lethal concentration 50% (LC50) data for juveniles of 3 commonly tested fish species: rainbow trout, bluegill sunfish, and sheepshead minnow. A poor, albeit significant, relationship (r2 = 0.28; p < 0.05) was found between zebrafish embryo and juvenile fish toxicity when pesticides were considered as a single group, but a much better relationship (r2 = 0.64; p < 0.05) when pesticide mode of action was factored into an analysis of covariance. This discrepancy is partly explained by the large number of neurotoxic pesticides in the dataset, supporting previous findings that commonly used fish embryo toxicity test endpoints are particularly insensitive to neurotoxicants. These results indicate that it is still premature to replace juvenile fish toxicity tests with embryo-based tests such as the Organisation for Economic Co-operation and Development Fish Embryo Acute Toxicity Test for routine pesticide hazard assessment, although embryo testing could be used with other screening tools for testing prioritization. Environ Toxicol Chem 2017;36:1221-1226. © 2016 SETAC.
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Affiliation(s)
- Scott Glaberman
- Department of Biology, University of South Alabama, Mobile, Alabama, USA
| | - Stephanie Padilla
- Integrated Systems Toxicology Division, US Environmental Protection Agency, Research Triangle Park, North Carolina, USA
| | - Mace G Barron
- Gulf Ecology Division, US Environmental Protection Agency, Gulf Breeze, Florida, USA
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108
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Ma Y, Jin J, Li P, Xu M, Sun Y, Wang Y, Yuan H. Organophosphate ester flame retardant concentrations and distributions in serum from inhabitants of Shandong, China, and changes between 2011 and 2015. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2017; 36:414-421. [PMID: 27391075 DOI: 10.1002/etc.3554] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 04/15/2016] [Accepted: 07/07/2016] [Indexed: 06/06/2023]
Abstract
The production and use of brominated flame retardants have been increasingly restricted. Organophosphate esters (OPEs) have been widely used as substitutes for brominated flame retardants. However, little is yet known about human exposure to OPEs. The potential health risks posed by OPEs were assessed by determining the concentrations of 6 OPEs in pooled serum samples from residents of Shandong, China. The mean ∑6 OPE concentrations in 2011 and 2015 were 680 ng/g lipid and 709 ng/g lipid, respectively. The most abundant OPE was tri(2-chloroethyl) phosphate, contributing a mean of 82% of the ∑6 OPE concentration. A significant correlation was found between the tri(2-chloroethyl) phosphate and tri-n-butylphosphate concentrations, possibly indicating that these OPEs are used in similar applications and have similar human exposure pathways in the study area. The mean tri(2-chloroethyl) phosphate concentration increased from 536 ng/g lipid in 2011 to 605 ng/g lipid in 2015, but the concentrations of tri-n-butylphosphate, triphenyl phosphate, and tris(methylphenyl) esters decreased between 2011 and 2015. This could indicate that chlorinated OPEs bioaccumulate in humans more strongly than nonchlorinated OPEs do. Environ Toxicol Chem 2017;36:414-421. © 2016 SETAC.
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Affiliation(s)
- Yulong Ma
- College of Life and Environmental Science, Minzu University of China, Beijing, China
| | - Jun Jin
- College of Life and Environmental Science, Minzu University of China, Beijing, China
- Engineering Research Center of Food Environment and Public Health, Beijing, China
| | - Peng Li
- College of Life and Environmental Science, Minzu University of China, Beijing, China
| | - Meng Xu
- College of Life and Environmental Science, Minzu University of China, Beijing, China
| | - Yiming Sun
- College of Life and Environmental Science, Minzu University of China, Beijing, China
| | - Ying Wang
- College of Life and Environmental Science, Minzu University of China, Beijing, China
| | - Haodong Yuan
- College of Life and Environmental Science, Minzu University of China, Beijing, China
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109
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Noyes PD, Garcia GR, Tanguay RL. ZEBRAFISH AS AN IN VIVO MODEL FOR SUSTAINABLE CHEMICAL DESIGN. GREEN CHEMISTRY : AN INTERNATIONAL JOURNAL AND GREEN CHEMISTRY RESOURCE : GC 2016; 18:6410-6430. [PMID: 28461781 PMCID: PMC5408959 DOI: 10.1039/c6gc02061e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Heightened public awareness about the many thousands of chemicals in use and present as persistent contaminants in the environment has increased the demand for safer chemicals and more rigorous toxicity testing. There is a growing recognition that the use of traditional test models and empirical approaches is impractical for screening for toxicity the many thousands of chemicals in the environment and the hundreds of new chemistries introduced each year. These realities coupled with the green chemistry movement have prompted efforts to implement more predictive-based approaches to evaluate chemical toxicity early in product development. While used for many years in environmental toxicology and biomedicine, zebrafish use has accelerated more recently in genetic toxicology, high throughput screening (HTS), and behavioral testing. This review describes major advances in these testing methods that have positioned the zebrafish as a highly applicable model in chemical safety evaluations and sustainable chemistry efforts. Many toxic responses have been shown to be shared among fish and mammals owing to their generally well-conserved development, cellular networks, and organ systems. These shared responses have been observed for chemicals that impair endocrine functioning, development, and reproduction, as well as those that elicit cardiotoxicity and carcinogenicity, among other diseases. HTS technologies with zebrafish enable screening large chemical libraries for bioactivity that provide opportunities for testing early in product development. A compelling attribute of the zebrafish centers on being able to characterize toxicity mechanisms across multiple levels of biological organization from the genome to receptor interactions and cellular processes leading to phenotypic changes such as developmental malformations. Finally, there is a growing recognition of the links between human and wildlife health and the need for approaches that allow for assessment of real world multi-chemical exposures. The zebrafish is poised to be an important model in bridging these two conventionally separate areas of toxicology and characterizing the biological effects of chemical mixtures that could augment its role in sustainable chemistry.
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Affiliation(s)
- Pamela D. Noyes
- Department of Environmental & Molecular Toxicology, Oregon State University, Corvallis, OR 97331
| | - Gloria R. Garcia
- Department of Environmental & Molecular Toxicology, Oregon State University, Corvallis, OR 97331
| | - Robert L. Tanguay
- Department of Environmental & Molecular Toxicology, Oregon State University, Corvallis, OR 97331
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110
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Wang G, Du Z, Chen H, Su Y, Gao S, Mao L. Tissue-Specific Accumulation, Depuration, and Transformation of Triphenyl Phosphate (TPHP) in Adult Zebrafish (Danio rerio). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:13555-13564. [PMID: 27993046 DOI: 10.1021/acs.est.6b04697] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Understanding bioaccumulation and metabolism is critical for evaluating the fate and potential toxicity of compounds in vivo. We recently investigated, for the first time, the bioconcentration and tissue distribution of triphenyl phosphate (TPHP) and its main metabolites in selected tissues of adult zebrafish. To further confirm the metabolites, deuterated TPHP (d15-TPHP) was used in the exposure experiments at an environmentally relevant level (20 μg/L) and at 1/10 LC50 (100 μg/L). After 11-14 days of exposure to 100 μg/L of d15-TPHP, the accumulation and excretion of d15-TPHP reached equilibrium, at which point the intestine contained the highest d15-TPHP (μg/g wet weight, ww) concentration (3.12 ± 0.43), followed by the gills (2.76 ± 0.12) > brain (2.58 ± 0.19) > liver (2.30 ± 0.34) ≫ muscle (0.53 ± 0.04). The major metabolite of d15-TPHP, d10-diphenyl phosphate (d10-DPHP), was detected at significantly higher contents in the liver and intestine, at levels up to 3.0-3.5 times those of d15-TPHP. The metabolic pathways of TPHP were elucidated, including hydrolysis, hydroxylation, and glucuronic acid conjugation after hydroxylation. Finally, a physiologically based toxicokinetic (PBTK) model was used to explore the key factors influencing the bioaccumulation of d15-TPHP in zebrafish. These results provide important information for the understanding of the metabolism, disposition, and toxicology of TPHP in aquatic organisms.
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Affiliation(s)
- Guowei Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210093, China
| | - Zhongkun Du
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210093, China
| | - Hanyan Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210093, China
| | - Yu Su
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210093, China
| | - Shixiang Gao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210093, China
| | - Liang Mao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210093, China
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111
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Krowech G, Hoover S, Plummer L, Sandy M, Zeise L, Solomon G. Identifying Chemical Groups for Biomonitoring. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:A219-A226. [PMID: 27905275 PMCID: PMC5132641 DOI: 10.1289/ehp537] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Regulatory agencies face daunting challenges identifying emerging chemical hazards because of the large number of chemicals in commerce and limited data on exposure and toxicology. Evaluating one chemical at a time is inefficient and can lead to replacement with uncharacterized chemicals or chemicals with structural features already linked to toxicity. The Office of Environmental Health Hazard Assessment (OEHHA) has developed a process for constructing and assessing chemical groups for potential biomonitoring in California. We screen for chemicals with significant exposure potential and propose possible chemical groups, based on structure and function. To support formal consideration of these groups by Biomonitoring California’s Scientific Guidance Panel, we conduct a detailed review of exposure and toxicity data and examine the likelihood of detection in biological samples. To date, 12 chemical groups have been constructed and added to the pool of chemicals that can be selected for Biomonitoring California studies, including p,p´-bisphenols, brominated and chlorinated organic compounds used as flame retardants, non-halogenated aromatic phosphates, and synthetic polycyclic musks. Evaluating chemical groups, rather than individual chemicals, is an efficient way to respond to shifts in chemical use and the emergence of new chemicals. This strategy can enable earlier identification of important chemicals for monitoring and intervention.
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Affiliation(s)
- Gail Krowech
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Sara Hoover
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Laurel Plummer
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Martha Sandy
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, Oakland, California, USA
| | - Gina Solomon
- California Environmental Protection Agency, Sacramento, California, USA
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112
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Li J, Ma X, Su G, Giesy JP, Xiao Y, Zhou B, Letcher RJ, Liu C. Multigenerational effects of tris(1,3-dichloro-2-propyl) phosphate on the free-living ciliate protozoa Tetrahymena thermophila exposed to environmentally relevant concentrations and after subsequent recovery. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 218:50-58. [PMID: 27552037 DOI: 10.1016/j.envpol.2016.08.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 07/29/2016] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is considered a re-emerging environmental pollutant, and exposure to environmentally relevant concentrations has been shown to cause individual developmental toxicity in zebrafish and the water flea (Daphnia magna). However, multigenerational effects during exposure to TDCIPP and after subsequent recovery were unknown. In the present study, individuals of a model aquatic organism, the ciliated protozoan, T. thermophila were exposed to environmentally-relevant concentrations of TDCIPP (0, 300 or 3000 ng/L) for 60 days (e.g., theoretically 372 generations) followed by a 60-day period of recovery, during which T. thermophila were not exposed to TDCIPP. During exposure and after exposure, effects at the molecular, histological, individual and population levels were examined. Multigenerational exposure to 300 or 3000 ng TDCIPP/L for 60 days significantly decreased numbers of individuals, sizes of individuals, expressed as length and width of bodies, number of cilia, and depth and diameter of basal bodies of cilia, and up-regulated expressions of genes related to assembly and maintenance of cilia. Complete or partial recoveries of theoretical sizes of populations as well as sizes of individuals and expressions of genes were observed during the 60-day recovery period. Effects on number of cilia and depth and diameter of basal body of cilia were not reversible and could still be observed long after cease of TDCIPP exposure. Collectedly, and shown for the first time, multigenerational effects to T. thermophila were caused by exposure to environmentally relevant concentrations of TDCIPP. Also, there were multi-generational effects at the population level that were not caused by carry-over exposure to TDCIPP. The "permanent" alterations and their potential significance are discussed.
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Affiliation(s)
- Jing Li
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Hubei Provincial Engineering Laboratory for Pond Aquaculture, China
| | - Xufa Ma
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Guanyong Su
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - John P Giesy
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B3, Canada; School of Biological Sciences, University of Hong Kong, Hong Kong Special Administrative Region; State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210089, China
| | - Yuan Xiao
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Bingsheng Zhou
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Robert J Letcher
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
| | - Chunsheng Liu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Collaborative Innovation Center for Efficient and Health Production of Fisheries in Hunan Province, Hunan, Changde 415000, China.
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113
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Volz DC, Leet JK, Chen A, Stapleton H, Katiyar N, Kaundal R, Yu Y, Wang Y. Tris(1,3-dichloro-2-propyl)phosphate Induces Genome-Wide Hypomethylation within Early Zebrafish Embryos. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:10255-63. [PMID: 27574916 PMCID: PMC5080636 DOI: 10.1021/acs.est.6b03656] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Tris(1,3-dichloro-2-propyl)phosphate (TDCIPP) is a high-production volume organophosphate-based plasticizer and flame retardant widely used within the United States. Using zebrafish as a model, the objectives of this study were to determine whether (1) TDCIPP inhibits DNA methyltransferase (DNMT) within embryonic nuclear extracts; (2) uptake of TDCIPP from 0.75 h postfertilization (hpf, 2-cell) to 2 hpf (64-cell) or 6 hpf (shield stage) leads to impacts on the early embryonic DNA methylome; and (3) TDCIPP-induced impacts on cytosine methylation are localized to CpG islands within intergenic regions. Within this study, 5-azacytidine (5-azaC, a DNMT inhibitor) was used as a positive control. Although 5-azaC significantly inhibited zebrafish DNMT, TDCIPP did not affect DNMT activity in vitro at concentrations as high as 500 μM. However, rapid embryonic uptake of 5-azaC and TDCIPP from 0.75 to 2 hpf resulted in chemical- and chromosome-specific alterations in cytosine methylation at 2 hpf. Moreover, TDCIPP exposure predominantly resulted in hypomethylation of positions outside of CpG islands and within intragenic (exon) regions of the zebrafish genome. Overall, these findings provide the foundation for monitoring DNA methylation dynamics within zebrafish as well as identifying potential associations among TDCIPP exposure, adverse health outcomes, and DNA methylation status within human populations.
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Affiliation(s)
- David C. Volz
- Department
of Environmental Sciences, University of
California, Riverside, Riverside, California 92521, United States
- D. C. Volz. Phone: (951)
827-4450; Fax: (951) 827-3993; E-mail:
| | - Jessica K. Leet
- Department
of Environmental Health Sciences, University
of South Carolina, Columbia, South Carolina 29208, United States
| | - Albert Chen
- Division
of Environmental Sciences and Policy, Duke
University, Durham, North Carolina 27708, United States
| | - Heather
M. Stapleton
- Division
of Environmental Sciences and Policy, Duke
University, Durham, North Carolina 27708, United States
| | - Neerja Katiyar
- Bioinformatics
Facility, Institute for Integrative Genome Biology, University of California, Riverside, Riverside, California 92521, United States
| | - Rakesh Kaundal
- Bioinformatics
Facility, Institute for Integrative Genome Biology, University of California, Riverside, Riverside, California 92521, United States
| | - Yang Yu
- Department
of Chemistry, University of California,
Riverside, Riverside, California 92521, United States
| | - Yinsheng Wang
- Department
of Chemistry, University of California,
Riverside, Riverside, California 92521, United States
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114
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Liu X, Jung D, Jo A, Ji K, Moon HB, Choi K. Long-term exposure to triphenylphosphate alters hormone balance and HPG, HPI, and HPT gene expression in zebrafish (Danio rerio). ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:2288-96. [PMID: 26865342 DOI: 10.1002/etc.3395] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/11/2015] [Accepted: 02/08/2016] [Indexed: 05/28/2023]
Abstract
With the global decline in the use of polybrominated diphenyl ethers, the demand for alternative flame retardants, such as triphenylphosphate (TPP), has increased substantially. Triphenylphosphate is now detected in various environments including aquatic ecosystems worldwide. However, studies on the toxicological consequences of chronic TPP exposure on aquatic organisms are scarce. The zebrafish model was used to investigate the effects of long-term TPP exposure on the endocrine system. Zebrafish embryos were exposed to 5 µg/L, 50 µg/L, or 500 µg/L TPP for 120 d, and hormonal and transcriptional responses were measured along the hypothalamic-pituitary-gonad (HPG) axis, the hypothalamic-pituitary-interrenal (HPI) axis, and the hypothalamic-pituitary-thyroid (HPT) axis. Exposure to TPP significantly increased plasma 17β-estradiol, but decreased 11-ketotestosterone in both sexes. Gene expression data support these changes. In the HPI axis, plasma cortisol and proopiomelanocortin (pomc) and mineralocorticoid receptor transcripts increased in females, but in males cortisol decreased whereas pomc increased (p < 0.05). Thyroxine and triiodothyronine increased, and thyrotrophin-releasing hormone receptor 2 (trhr2) and trh expression were affected only in females (p < 0.05). In summary, long-term exposure to TPP enhanced estrogenicity in both males and females, potentially through influencing the HPG axis, but modulated the HPI, and HPT axes differently by sex, suggesting that both genomic and nongenomic responses might be involved. Environ Toxicol Chem 2016;35:2288-2296. © 2016 SETAC.
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Affiliation(s)
- Xiaoshan Liu
- School of Public Health, Seoul National University, Seoul, Republic of Korea
- School of Public Health, Guangdong Medical University, Dongguan City, Guangdong Province, People's Republic of China
| | - Dawoon Jung
- School of Public Health, Seoul National University, Seoul, Republic of Korea
- Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea
| | - Areum Jo
- School of Public Health, Seoul National University, Seoul, Republic of Korea
- National Institute of Environmental Research, Incheon, Republic of Korea
| | - Kyunghee Ji
- Department of Occupational and Environmental Health, Yongin University, Yongin, Republic of Korea
| | - Hyo-Bang Moon
- Department of Marine Sciences and Convergent Technology, Hanyang University, Ansan, Republic of Korea
| | - Kyungho Choi
- School of Public Health, Seoul National University, Seoul, Republic of Korea
- Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea
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115
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Behl M, Rice JR, Smith MV, Co CA, Bridge MF, Hsieh JH, Freedman JH, Boyd WA. Editor's Highlight: Comparative Toxicity of Organophosphate Flame Retardants and Polybrominated Diphenyl Ethers to Caenorhabditis elegans. Toxicol Sci 2016; 154:241-252. [PMID: 27566445 DOI: 10.1093/toxsci/kfw162] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
With the phasing-out of the polybrominated diphenyl ether (PBDE) flame retardants due to concerns regarding their potential developmental toxicity, the use of replacement compounds such as organophosphate flame retardants (OPFRs) has increased. Limited toxicity data are currently available to estimate the potential adverse health effects of the OPFRs. The toxicological effects of 4 brominated flame retardants, including 3 PBDEs and 3,3',5,5'-tetrabromobisphenol A, were compared with 6 aromatic OPFRs and 2 aliphatic OPFRs. The effects of these chemicals were determined using 3 biological endpoints in the nematode Caenorhabditis elegans (feeding, larval development, and reproduction). Because C. elegans development was previously reported to be sensitive to mitochondrial function, results were compared with those from an in vitro mitochondrial membrane permeabilization (MMP) assay. Overall 11 of the 12 flame retardants were active in 1 or more C. elegans biological endpoints, with only tris(2-chloroethyl) phosphate inactive across all endpoints including the in vitro MMP assay. For 2 of the C. elegans endpoints, at least 1 OPFR had similar toxicity to the PBDEs: triphenyl phosphate (TPHP) inhibited larval development at levels comparable to the 3 PBDEs; whereas TPHP and isopropylated phenol phosphate (IPP) affected C. elegans reproduction at levels similar to the PBDE commercial mixture, DE-71. The PBDEs reduced C. elegans feeding at lower concentrations than any OPFR. In addition, 9 of the 11 chemicals that inhibited C. elegans larval development also caused significant mitochondrial toxicity. These results suggest that some of the replacement aromatic OPFRs may have levels of toxicity comparable to PBDEs.
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Affiliation(s)
- Mamta Behl
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, North Carolina
| | - Julie R Rice
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, North Carolina
| | - Marjo V Smith
- Social & Scientific Systems, Inc., Durham, North Carolina
| | - Caroll A Co
- Social & Scientific Systems, Inc., Durham, North Carolina
| | | | - Jui-Hua Hsieh
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, North Carolina
| | - Jonathan H Freedman
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, Kentucky
| | - Windy A Boyd
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, North Carolina
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116
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Chlebowski AC, Tanguay RL, Simonich SLM. Quantitation and prediction of sorptive losses during toxicity testing of polycyclic aromatic hydrocarbon (PAH) and nitrated PAH (NPAH) using polystyrene 96-well plates. Neurotoxicol Teratol 2016; 57:30-38. [PMID: 27170619 DOI: 10.1016/j.ntt.2016.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 05/02/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
Abstract
Developing zebrafish are increasingly being used for rapid assessments of chemical toxicity, and these assays are frequently conducted in multi-well plastic plates. This study investigated the sorptive behavior of polycyclic aromatic hydrocarbons (PAHs) and nitrated PAHs (NPAHs) to uncoated 96-well polystyrene plates typically used for zebrafish (Danio rerio) testing. We measured the percent sorption in the presence and absence of zebrafish embryos, at two exposure concentrations, as well as using two different procedures (addition of embryos to polystyrene plates either before analyte addition, or allowing 24h of equilibrium between analyte addition and embryo addition to the polystyrene plates). Following exposure, the plates were extracted with hexane and analyzed using gas chromatography coupled with mass spectrometry (GC/MS). Allowing 24h of pre-incubation between the addition of analytes and embryos did not significantly impact the percent sorption. The percent sorption was higher for both PAHs and NPAHs at the lower exposure concentration, and sorption was lower in the presence of zebrafish embryos. A mass balance model was developed to predict the sorption to polystyrene plates, based on the PAH and NPAH mass distribution ratios between polystyrene and water. While PAH sorption was significantly correlated with subcooled liquid solubility, NPAH sorption did not correlate with any of the physical-chemical properties investigated. This indicates the need to better understand the sorptive behavior of hydrophobic analytes to plastics, and to better account for sorptive losses during toxicity testing in polystyrene plates.
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Affiliation(s)
- Anna C Chlebowski
- Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture and Life Sciences Building, Corvallis, OR 97331, United States.
| | - Robert L Tanguay
- Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture and Life Sciences Building, Corvallis, OR 97331, United States.
| | - Staci L Massey Simonich
- Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture and Life Sciences Building, Corvallis, OR 97331, United States; Department of Chemistry, 153A Gilbert Hall, 2100 SW Campus Way, Corvallis, OR 97331, United States.
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117
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Weis CP. The Value of Alternatives Assessment. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:A40. [PMID: 26930551 PMCID: PMC4786994 DOI: 10.1289/ehp.1611248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Affiliation(s)
- Christopher P Weis
- National Institute of Environmental Health Sciences, National Institutes of Health, U.S. Department of Health and Human Services, Bethesda, Maryland, USA
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118
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Neurite outgrowth in human induced pluripotent stem cell-derived neurons as a high-throughput screen for developmental neurotoxicity or neurotoxicity. Neurotoxicology 2016; 53:271-281. [PMID: 26854185 DOI: 10.1016/j.neuro.2016.02.003] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 02/01/2016] [Accepted: 02/02/2016] [Indexed: 11/21/2022]
Abstract
Due to the increasing prevalence of neurological disorders and the large number of untested compounds in the environment, there is a need to develop reliable and efficient screening tools to identify environmental chemicals that could potentially affect neurological development. Herein, we report on a library of 80 compounds screened for their ability to inhibit neurite outgrowth, a process by which compounds may elicit developmental neurotoxicity, in a high-throughput, high-content assay using human neurons derived from induced pluripotent stem cells (iPSC). The library contains a diverse set of compounds including those that have been known to be associated with developmental neurotoxicity (DNT) and/or neurotoxicity (NT), environmental compounds with unknown neurotoxic potential (e.g., polycyclic aromatic hydrocarbons (PAHs) and flame retardants (FRs)), as well as compounds with no documented neurotoxic potential. Neurons were treated for 72h across a 6-point concentration range (∼0.3-100μM) in 384-well plates. Effects on neurite outgrowth were assessed by quantifying total outgrowth, branches, and processes. We also assessed the number ofviable cells per well. Concentration-response profiles were evaluated using a Hill model to derive benchmark concentration (BMC) values. Assay performance was evaluated using positive and negative controls and test replicates. Compounds were ranked by activity and selectivity (i.e., specific effects on neurite outgrowth in the absence of concomitant cytotoxicity) and repeat studies were conducted to confirm selectivity. Among the 80 compounds tested, 38 compounds were active, of which 16 selectively inhibited neurite outgrowth. Of these 16 compounds, 12 were known to cause DNT/NT and the remaining 4 compounds included 3 PAHs and 1 FR. In independent repeat studies, 14/16 selective compounds were reproducibly active in the assay, of which only 6 were selective for inhibition of neurite outgrowth. These 6 compounds were previously shown in the literature to be neurotoxic. These studies shed light on the current status of human iPSCs in DNT/NT screening and their utility in identifying, ranking, and prioritizing compounds with DNT/NT potential for further in vivo testing.
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119
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Use of alternative assays to identify and prioritize organophosphorus flame retardants for potential developmental and neurotoxicity. Neurotoxicol Teratol 2015; 52:181-93. [DOI: 10.1016/j.ntt.2015.09.003] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 09/02/2015] [Accepted: 09/02/2015] [Indexed: 12/26/2022]
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120
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Hendriks HS, Westerink RH. Neurotoxicity and risk assessment of brominated and alternative flame retardants. Neurotoxicol Teratol 2015; 52:248-69. [DOI: 10.1016/j.ntt.2015.09.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 09/01/2015] [Accepted: 09/01/2015] [Indexed: 11/29/2022]
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121
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Moser VC, Phillips PM, Hedge JM, McDaniel KL. Neurotoxicological and thyroid evaluations of rats developmentally exposed to tris(1,3-dichloro-2-propyl)phosphate (TDCIPP) and tris(2-chloro-2-ethyl)phosphate (TCEP). Neurotoxicol Teratol 2015; 52:236-47. [PMID: 26300399 DOI: 10.1016/j.ntt.2015.08.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 08/10/2015] [Accepted: 08/17/2015] [Indexed: 02/03/2023]
Abstract
Tris(1,3-dichloro-2-propyl)phosphate (TDCIPP) and tris(2-chloro-2-ethyl)phosphate (TCEP) are organophosphorous flame retardants with widespread usage and human exposures through food, inhalation, and dust ingestion. They have been detected in human tissues including urine and breast milk. Reports of disrupted neural growth in vitro, abnormal development in larval zebrafish, and altered thyroid hormones in several species have raised concern for neurodevelopmental toxicity. This is especially the case for TDCIPP, which is more potent and has more activity in those assays than does TCEP. We evaluated the potential for developmental neurotoxicity of TDCIPP and TCEP in a mammalian model. Pregnant Long-Evans rats were administered TDCIPP (15, 50, or 150 mg/kg/day) or TCEP (12, 40, 90 mg/kg/day) via oral gavage from gestational day 10 to weaning. Corn oil was the vehicle control in both studies. Body weight and righting reflex development were monitored in all pups. A subset of offspring at culling and weaning, and dams at weaning, were sacrificed for serum and organ collection for measurement of brain, liver, and thyroid weights, serum thyroid levels, and serum and brain acetylcholinesterase activities. Brain weights were also measured in a group of adult TDCIPP-treated offspring. One male and one female from each litter were allocated for behavioral testing at several ages: standard locomotor activity (preweaning, postweaning, adults), locomotor activity including a lighting change mid-way (postweaning, adults), elevated zero maze (postweaning, adults), functional observational battery (FOB; postweaning, adults), and Morris water maze (place learning, reference and working memory; adults). Neither chemical produced changes in maternal body weight or serum thyroid hormones, but relative liver weight was increased at the high doses of both TDCIPP and TCEP. In offspring, there were no effects on viability, litter size, or birth weight. With TDCIPP, absolute liver weights were lower at weaning and weight gain was lower in the high-dose offspring until about two months of age. Thyroid hormones and brain weights were not altered and acetylcholinesterase (both brain and serum) was not inhibited by either chemical. TDCIPP-treated offspring showed slight differences in floating in the water maze, hindlimb grip strength, and altered activity habituation, whereas TCEP-treated rats showed differences in quadrant time (probe) and middle-zone preference in the water maze. Regarding these few changes, the effects were minimal, mostly not related to dose, and did not appear treatment-related or biologically significant. Overall, these data do not support the potential for thyrotoxicity or developmental neurotoxicity produced by TDCIPP or TCEP.
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Affiliation(s)
- Virginia C Moser
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
| | - Pamela M Phillips
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA
| | - Joan M Hedge
- Integrated Systems Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA
| | - Katherine L McDaniel
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA
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