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Tam N, Kong RYC, Lai KP. Reproductive toxicity in marine medaka (Oryzias melastigma) due to embryonic exposure to PCB 28 or 4'-OH-PCB 65. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 874:162401. [PMID: 36842578 DOI: 10.1016/j.scitotenv.2023.162401] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/15/2023] [Accepted: 02/18/2023] [Indexed: 06/18/2023]
Abstract
Previous studies have shown that juvenile or adult exposure to polychlorinated biphenyls (PCBs) induces alterations in reproductive functions (e.g., reduced fertilization rate) and behavior (e.g., reduced nest maintenance) in fish. Embryonic exposures to other endocrine disrupting chemicals have been reported to induce long-term reproductive toxicity in fish. However, the effects of embryonic exposure to PCBs or their metabolites, OH-PCBs, on long-term reproductive function in fish are unknown. In the present study, we used the marine medaka fish (Oryzias melastigma) as a model to assess the reproductive endpoints in response to embryonic exposure to either PCB 28 or 4'-OH-PCB 65. Our results showed that the sex ratio of marine medaka was feminized by exposure to 4'-OH-PCB 65. Fecundity was decreased in the medaka treated with either PCB 28 or 4'-OH-PCB 65, whereas the medaka from embryonic exposure to 4'-OH-PCB 65 additionally exhibited reduced fertilization and a reduction in the hatching success rate of offspring, as well as decreased sperm motility. Serum 11-KT concentrations were reduced in the PCB 28-treated medaka, and serum estradiol (E2)/testosterone (T) and E2/11-ketotestosterone (11-KT) ratios were decreased in the 4'-OH-PCB 65-treated medaka. To explain these observations at the molecular level, transcriptomic analysis of the gonads was performed. Bioinformatic analysis using Gene Ontology and Ingenuity Pathway Analysis revealed that genes involved in various pathways potentially involved in reproductive functions (e.g., steroid metabolism and cholesterol homeostasis) were differentially expressed in the testes and ovaries of either PCB- or OH-PCB-treated medaka. Thus, the long-term reproductive toxicity in fish due to embryonic exposure to PCB or OH-PCB should be considered for environmental risk assessment.
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Affiliation(s)
- Nathan Tam
- Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong
| | - Richard Yuen Chong Kong
- Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong.
| | - Keng Po Lai
- Key Laboratory of Environmental Pollution and Integrative Omics, Guilin Medical University, Education Department of Guangxi Zhuang Autonomous Region, China; Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong.
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2
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Liu X, Mullin MR, Egeghy P, Woodward KA, Compton KC, Nickel B, Aguilar M, Folk E. Inadvertently Generated PCBs in Consumer Products: Concentrations, Fate and Transport, and Preliminary Exposure Assessment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:12228-12236. [PMID: 35943277 PMCID: PMC9511961 DOI: 10.1021/acs.est.2c02517] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Although commercial polychlorinated biphenyl (PCB) production was banned in 1979 under the Toxics Substance Control Act, inadvertent generation of PCBs through a variety of chemical production processes continues to contaminate products and waste streams. In this research, a total of 39 consumer products purchased from local and online retailer stores were analyzed for 209 PCB congeners. Inadvertent PCBs (iPCBs) were detected from seven products, and PCB-11 was the only congener detected in most of the samples, with a maximum concentration exceeding 800 ng/g. Emission of PCB-11 to air was studied from one craft foam sheet product using dynamic microchambers at 40 °C for about 120 days. PCB-11 migration from the product to house dust was also investigated. The IAQX program was then employed to estimate the emissions of PCB-11 from 10 craft foam sheets to indoor air in a 30 m3 room at 0.5 h-1 air change rate for 30 days. The predicted maximum PCB-11 concentration in the room air (156.8 ng/m3) and the measured concentration in dust (20 ng/g) were applied for the preliminary exposure assessment. The generated data from multipathway investigation in this work should be informative for further risk assessment and management for iPCBs.
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Affiliation(s)
- Xiaoyu Liu
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Measurement & Modeling, Research Triangle Park, NC 27711, USA
| | - Michelle R. Mullin
- U.S. Environmental Protection Agency, Region 10, Land, Chemicals, and Redevelopment Division, Seattle, WA 98101, USA
| | - Peter Egeghy
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Computational Toxicology and Exposure, Research Triangle Park, NC 27711, USA
| | - Katherine A. Woodward
- U.S. Environmental Protection Agency, Region 1, Land, Chemicals, and Redevelopment Division, Boston, MA 02109, USA
| | - Kathleen C. Compton
- U.S. Environmental Protection Agency, Region 10, Land, Chemicals, and Redevelopment Division, Seattle, WA 98101, USA
| | - Brian Nickel
- U.S. Environmental Protection Agency, Region 10, Water Division, Seattle, WA 98101, USA
| | - Marcus Aguilar
- U.S. Environmental Protection Agency, Region 9, Land, Chemicals, and Redevelopment Division, San Francisco, CA 94105, USA
| | - Edgar Folk
- Jacobs, Critical Mission Solutions, EPA - Research Laboratory Support, Research Triangle Park, NC 27711, USA
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3
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Wang S, Wang MY, Shi YF, Han F, Ye HL, Cai YQ, Wu D, Tian LL, Zhang X, Tang YY. Identification of 2,2',4,5,5'-Pentachlorobiphenyl (PCB101) metabolites and their transmission characteristics in silver crucian carp (Carassius auratus gibelio). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 307:119583. [PMID: 35680065 DOI: 10.1016/j.envpol.2022.119583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 05/24/2022] [Accepted: 06/03/2022] [Indexed: 06/15/2023]
Abstract
Polychlorinated biphenyls (PCBs) have been attracting global concern due to their persistence and toxicity. However, the study on the metabolites of PCBs in freshwater fish is limited. In this study, the metabolites of 2,2',4,5,5'-Pentachlorobiphenyl (PCB101) in silver crucian carp (Carassius auratus gibelio) were identified for the first time. After intraperitoneal injection of PCB101 (2 mg/kg), the results showed that it could be metabolized to at least three types of metabolites, including hydroxylated (OH-), methoxylated (MeO-) and methyl sulfonated (MeSO2-) PCB101. The OH- metabolites identified in most tissues were 3-OH-PCB101and 4-OH-PCB101, such as liver, gallbladder, blood and muscle. MeSO2- metabolites identified in gallbladder, blood and brain were 3-MeSO2-PCB101 and 4-MeSO2-PCB101. Meanwhile, the MeO- metabolite identified in liver, gallbladder, blood and spleen of silver crucian carp was 4-MeO-PCB101. The investigation of the types and structures of PCB101 and its metabolites, as well as the tissue distribution and accumulation characteristics in silver crucian carp are beneficial to understand the transformation and metabolic mechanisms of PCBs in aquatic organisms. It is of great significance to identify potential pollution hazards of precursor compounds and their metabolites on aquatic products and ensure the quality and safety of aquatic products.
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Affiliation(s)
- Shuai Wang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China; College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, China; Linquan County Agricultural Product Quality and Safety Inspection Station, Linquan, Anhui province, China
| | - Meng-Yuan Wang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China; College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, China
| | - Yong-Fu Shi
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China.
| | - Feng Han
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China; College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, China
| | - Hong-Li Ye
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China
| | - You-Qiong Cai
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China
| | - Di Wu
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China; College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, China
| | - Liang-Liang Tian
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China
| | - Xuan Zhang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China
| | - Yun-Yu Tang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, No. 300 Jungong Road, Yangpu District, Shanghai, 200090, China
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Mega OO, Edesiri TP, Victor E, Kingsley NE, Rume RA, Faith FY, Simon OI, Oghenetega BO, Agbonifo-Chijiokwu E. d-ribose- l-cysteine abrogates testicular maladaptive responses induced by polychlorinated bisphenol intoxication in rats via activation of the mTOR signaling pathway mediating inhibition of apoptosis, inflammation, and oxidonitrergic flux. J Biochem Mol Toxicol 2022; 36:e23161. [PMID: 35822628 DOI: 10.1002/jbt.23161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 04/12/2022] [Accepted: 07/01/2022] [Indexed: 11/06/2022]
Abstract
Male reproductive maladaptive responses are becoming a global health concern and also a social issue. Polychlorinated biphenyls (PCBs) are a member of halogenated aromatic environmental pollutants with diverse environmental matrices. This study was conducted to explore the mechanisms of PCBs-induced testicular maladaptive responses and the potential reversal effects of d-ribose- l-cysteine (DRLC) on testicular injury induced by administration of PCBs (2 mg/kg) for 30 days. DRLC (50 mg/kg) was administered orally for 15 days starting from Days 16 to 30 after the initial 15 days of treatment with PCB. All assays were carried out using established protocols. Administration of DRLC at 50 mg/kg after treatment with PCBs enhances body and testicular weights, gonadotropins (luteinizing hormone and follicle-stimulating hormone), testosterone and poor sperm quality. DRLC also reduced testicular injury score, improved spermatogenesis scoring, reduced oxidative stress biomarkers (malondialdehyde), as well as restored the reduced activities of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, and catalase) and decreases pro-inflammatory response (tumor necrosis factor-alpha and NO). More so, DRLC treatment abrogates testicular DNA fragmentation and downregulated p53 and caspase 3 activities and upregulated the concentration of autophagy-related protein (mammalian target of rapamycin [mTOR] and Atg7). DRLC abates testicular deficit induced by PCBs intoxicated rats via activation of the mTOR signaling pathway mediating inhibition of apoptosis, Inflammation and oxidative flux.
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Affiliation(s)
- Oyovwi O Mega
- Department of Hunan Physiology, Achievers University, Owo, Ondo State, Nigeria
| | - Tesi P Edesiri
- Department of Science Laboratory Technology, Delta State Polytechnic, Ogwashi-Uku, Delta State, Nigeria
| | - Emojevwe Victor
- Department of Physiology, University of Medical Sciences, Ondo, Ondo State, Nigeria
| | - Nwangwan E Kingsley
- Department of Pharmacology, Faculty of Basic Medical Science, College of Health Sciences, Delta State University, Abraka, Delta State, Nigeria
| | - Rotu A Rume
- Department of Physiology, Faculty of Basic Medical Science, Babcock University, Illisan-Romo, Ogun State, Nigeria
| | - Falajiki Y Faith
- Department of Hunan Physiology, Achievers University, Owo, Ondo State, Nigeria
| | - Ovuakporaye I Simon
- Department of Pharmacology, Faculty of Basic Medical Science, College of Health Sciences, Delta State University, Abraka, Delta State, Nigeria
| | - Bright O Oghenetega
- Department of Physiology, Faculty of Basic Medical Science, Babcock University, Illisan-Romo, Ogun State, Nigeria
| | - Ejime Agbonifo-Chijiokwu
- Department of Pharmacology, Faculty of Basic Medical Science, College of Health Sciences, Delta State University, Abraka, Delta State, Nigeria
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5
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Semkova V, Haupt S, Segschneider M, Bell C, Ingelman-Sundberg M, Hajo M, Weykopf B, Muthukottiappan P, Till A, Brüstle O. Dynamics of Metabolic Pathways and Stress Response Patterns during Human Neural Stem Cell Proliferation and Differentiation. Cells 2022; 11:cells11091388. [PMID: 35563695 PMCID: PMC9100042 DOI: 10.3390/cells11091388] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 03/30/2022] [Accepted: 04/12/2022] [Indexed: 02/05/2023] Open
Abstract
Understanding early nervous system stress response mechanisms is crucial for studying developmental neurotoxicity and devising neuroprotective treatments. We used hiPSC-derived long-term self-renewing neuroepithelial stem (lt-NES) cells differentiated for up to 12 weeks as an in vitro model of human neural development. Following a transcriptome analysis to identify pathway alterations, we induced acute oxidative stress (OS) using tert-butyl hydroperoxide (TBHP) and assessed cell viability at different stages of neural differentiation. We studied NRF2 activation, autophagy, and proteasomal function to explore the contribution and interplay of these pathways in the acute stress response. With increasing differentiation, lt-NES cells showed changes in the expression of metabolic pathway-associated genes with engagement of the pentose phosphate pathway after 6 weeks, this was accompanied by a decreased susceptibility to TBHP-induced stress. Microarray analysis revealed upregulation of target genes of the antioxidant response KEAP1–NRF2–ARE pathway after 6 weeks of differentiation. Pharmacological inhibition of NRF2 confirmed its vital role in the increased resistance to stress. While autophagy was upregulated alongside differentiation, it was not further increased upon oxidative stress and had no effect on stress-induced cell loss and the activation of NRF2 downstream genes. In contrast, proteasome inhibition led to the aggravation of the stress response resulting in decreased cell viability, derangement of NRF2 and KEAP1 protein levels, and lacking NRF2-pathway activation. Our data provide detailed insight into the dynamic regulation and interaction of pathways involved in modulating stress responses across defined time points of neural differentiation.
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Affiliation(s)
- Vesselina Semkova
- Institute of Reconstructive Neurobiology, Medical Faculty & University Hospital Bonn, University of Bonn, 53127 Bonn, Germany
- LIFE & BRAIN GmbH, Cellomics Unit, 53127 Bonn, Germany
| | - Simone Haupt
- LIFE & BRAIN GmbH, Cellomics Unit, 53127 Bonn, Germany
| | | | - Catherine Bell
- Karolinska Institute, Department of Physiology and Pharmacology, 171 77 Stockholm, Sweden
| | | | - Mohamad Hajo
- Institute of Reconstructive Neurobiology, Medical Faculty & University Hospital Bonn, University of Bonn, 53127 Bonn, Germany
| | - Beatrice Weykopf
- Institute of Reconstructive Neurobiology, Medical Faculty & University Hospital Bonn, University of Bonn, 53127 Bonn, Germany
| | - Pathma Muthukottiappan
- Institute of Reconstructive Neurobiology, Medical Faculty & University Hospital Bonn, University of Bonn, 53127 Bonn, Germany
| | - Andreas Till
- Institute of Reconstructive Neurobiology, Medical Faculty & University Hospital Bonn, University of Bonn, 53127 Bonn, Germany
- Correspondence: (A.T.); (O.B.)
| | - Oliver Brüstle
- Institute of Reconstructive Neurobiology, Medical Faculty & University Hospital Bonn, University of Bonn, 53127 Bonn, Germany
- Correspondence: (A.T.); (O.B.)
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6
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Slováčková J, Slavík J, Kulich P, Večeřa J, Kováč O, Paculová H, Straková N, Fedr R, Silva JP, Carvalho F, Machala M, Procházková J. Polychlorinated environmental toxicants affect sphingolipid metabolism during neurogenesis in vitro. Toxicology 2021; 463:152986. [PMID: 34627992 DOI: 10.1016/j.tox.2021.152986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 09/17/2021] [Accepted: 10/05/2021] [Indexed: 10/20/2022]
Abstract
Sphingolipids (SLs) are important signaling molecules and functional components of cellular membranes. Although SLs are known as crucial regulators of neural cell physiology and differentiation, modulations of SLs by environmental neurotoxicants in neural cells and their neuronal progeny have not yet been explored. In this study, we used in vitro models of differentiated neuron-like cells, which were repeatedly exposed during differentiation to model environmental toxicants, and we analyzed changes in sphingolipidome, cellular morphology and gene expression related to SL metabolism or neuronal differentiation. We compared these data with the results obtained in undifferentiated neural cells with progenitor-like features. As model polychlorinated organic pollutants, we used 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3'-dichlorobiphenyl (PCB11) and 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153). PCB153 revealed itself as the most prominent deregulator of SL metabolism and as potent toxicant during early phases of in vitro neurogenesis. TCDD exerted only minor changes in the levels of analysed lipid species, however, it significantly changed the rate of pro-neuronal differentiation and deregulated expression of neuronal markers during neurogenesis. PCB11 acted as a potent disruptor of in vitro neurogenesis, which induced significant alterations in SL metabolism and cellular morphology in both differentiated neuron-like models (differentiated NE4C and NG108-15 cells). We identified ceramide-1-phosphate, lactosylceramides and several glycosphingolipids to be the most sensitive SL species to exposure to polychlorinated pollutants. Additionally, we identified deregulation of several genes related to SL metabolism, which may be explored in future as potential markers of developmental neurotoxicity.
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Affiliation(s)
- Jana Slováčková
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | - Josef Slavík
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | - Pavel Kulich
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | - Josef Večeřa
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | - Ondrej Kováč
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | - Hana Paculová
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | - Nicol Straková
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | - Radek Fedr
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 61265, Brno, Czech Republic
| | - João Pedro Silva
- Laboratory of Toxicology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Portugal
| | - Félix Carvalho
- Laboratory of Toxicology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Portugal
| | - Miroslav Machala
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic.
| | - Jiřina Procházková
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic; Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 61265, Brno, Czech Republic.
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7
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Anh HQ, Watanabe I, Minh TB, Takahashi S. Unintentionally produced polychlorinated biphenyls in pigments: An updated review on their formation, emission sources, contamination status, and toxic effects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 755:142504. [PMID: 33035974 DOI: 10.1016/j.scitotenv.2020.142504] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/31/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
The formation, emission, environmental occurrence, and potential adverse effects of unintentionally produced polychlorinated biphenyls (PCBs) in pigments are reviewed, providing a comprehensive and up-to-date picture on these pollutants. PCBs are typically formed during manufacturing of organic pigments that involve chlorinated intermediates and reaction solvents, rather than those of inorganic pigments. Concentrations and profiles of PCBs vary greatly among pigment types and producers, with total PCB levels ranging from lower than detection limits to several hundred ppm; major components can be low-chlorinated (e.g., CB-11) or high-chlorinated congeners (e.g., CB-209). Pigment-derived PCBs can be released into the environment through different steps including pigment production, application, and disposal. They can contaminate atmospheric, terrestrial, and aquatic ecosystems, and then affect organisms living there. This situation garners scientific and public attention to nonlegacy emissions of PCBs and suggests the need for appropriate monitoring, management, and abatement strategies regarding these pollutants.
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Affiliation(s)
- Hoang Quoc Anh
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 100000, Viet Nam.
| | - Isao Watanabe
- Center of Advanced Technology for the Environment (CATE), Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan
| | - Tu Binh Minh
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19 Le Thanh Tong, Hanoi 100000, Viet Nam
| | - Shin Takahashi
- Center of Advanced Technology for the Environment (CATE), Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Japan.
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8
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Roy MA, Duche PR, Timme-Laragy AR. The sulfate metabolite of 3,3'-dichlorobiphenyl (PCB-11) impairs Cyp1a activity and increases hepatic neutral lipids in zebrafish larvae (Danio rerio). CHEMOSPHERE 2020; 260:127609. [PMID: 32693259 PMCID: PMC7530052 DOI: 10.1016/j.chemosphere.2020.127609] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/02/2020] [Accepted: 07/03/2020] [Indexed: 05/25/2023]
Abstract
The environmental contaminant 3,3'-dichlorobiphenyl (PCB-11) is widely detected in environmental samples, and this parent compound along with its metabolites 4-OH-PCB-11 and 4-PCB-11-Sulfate are detected in human serum. Our previous research in zebrafish (Danio rerio) embryos shows exposure to 20 μM PCB-11 inhibits Cyp1a enzyme activity and perturbs lipid metabolism pathways. In this study, wildtype AB embryos underwent acute exposures from 1 to 4 days post fertilization (dpf) to 0.002-20 μM 4-OH-PCB-11 or 0.2-20 μM 4-PCB-11-Sulfate, with and without co-exposures to 100 μg/L benzo[a]pyrene (B[a]P) or 5 nM 3,3',4,4',5-pentachlorobiphenyl (PCB-126), and were assessed for in vivo EROD activity and morphometrics. Chronic exposures from 1 to 15 dpf to assess lipid accumulation using Oil-Red-O staining were also conducted with 0.2 μM parent or metabolite compounds, alongside a co-exposure experiment of 0.002-0.2 μM 4-PCB-11-Sulfate and 10 μg/L B[a]P. For acute experiments, 2 and 20 μM 4-OH-PCB-11 was lethal but no Cyp1a or morphological effects were observed at lower concentrations; 20 μM 4-PCB-11-Sulfate significantly lowered the Cyp1a activity of B[a]P and PCB-126 but did not alter morphological development. For chronic experiments, 0.2 μM 4-PCB-11-Sulfate significantly increased lipid accumulation 30% in single exposures and 44% in co-exposures with B[a]P. Further long-term studies would better elucidate the effects of this contaminant, particularly in the context of environmentally-relevant mixtures.
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Affiliation(s)
- Monika A Roy
- Department of Environmental Health Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Perseverance R Duche
- Department of Environmental Health Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Alicia R Timme-Laragy
- Department of Environmental Health Sciences, University of Massachusetts Amherst, Amherst, MA, 01003, USA.
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9
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Zhang CY, Flor S, Ruiz P, Dhakal R, Hu X, Teesch LM, Ludewig G, Lehmler HJ. 3,3'-Dichlorobiphenyl Is Metabolized to a Complex Mixture of Oxidative Metabolites, Including Novel Methoxylated Metabolites, by HepG2 Cells. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:12345-12357. [PMID: 32910851 PMCID: PMC7544623 DOI: 10.1021/acs.est.0c03476] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
3,3'-Dichlorobiphenyl (PCB 11) is a byproduct of industrial processes and detected in environmental samples. PCB 11 and its metabolites are present in human serum, and emerging evidence demonstrates that PCB 11 is a developmental neurotoxicant. However, little is known about the metabolism of PCB 11 in humans. Here, we investigated the metabolism of PCB 11 and the associated metabolomics changes in HepG2 cells using untargeted high-resolution mass spectrometry. HepG2 cells were exposed for 24 h to PCB 11 in DMSO or DMSO alone. Cell culture media were analyzed with ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry. Thirty different metabolites were formed by HepG2 cells exposed to 10 μM PCB 11, including monohydroxylated, dihydroxylated, methoxylated-hydroxylated, and methoxylated-dihydroxylated metabolites and the corresponding sulfo and glucuronide conjugates. The methoxylated PCB metabolites were observed for the first time in a human-relevant model. 4-OH-PCB 11 (3,3'-dichlorobiphenyl-4-ol) and the corresponding catechol metabolite, 4,5-di-OH-PCB 11 (3',5-dichloro-3,4-dihydroxybiphenyl), were unambiguously identified based on liquid and gas chromatographic analyses. PCB 11 also altered several metabolic pathways, in particular vitamin B6 metabolism. These results demonstrate that complex PCB 11 metabolite profiles are formed in HepG2 cells that warrant further toxicological investigation, particularly since catechol metabolites are likely reactive and toxic.
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Affiliation(s)
- Chun-Yun Zhang
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Susanne Flor
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Patricia Ruiz
- Divison of Toxicology and Human Health Sciences, Computational Toxicology and Methods Development Lab, Agency for Toxic Substances and Disease Registry, Atlanta, Georgia 30333, United States
| | - Ram Dhakal
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Xin Hu
- Department of Medicine, School of Medicine, Emory University, Atlanta, GA 30303, United States
| | - Lynn M. Teesch
- High Resolution Mass Spectrometry Facility, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Gabriele Ludewig
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
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10
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Saktrakulkla P, Lan T, Hua J, Marek RF, Thorne PS, Hornbuckle KC. Polychlorinated Biphenyls in Food. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:11443-11452. [PMID: 32816464 PMCID: PMC7759298 DOI: 10.1021/acs.est.0c03632] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We measured the concentrations of 205 polychlorinated biphenyl (PCB) congeners in 26 food items: beef steak, butter, canned tuna, catfish, cheese, eggs, french fries, fried chicken, ground beef, ground pork, hamburger, hot dog, ice cream, liver, luncheon meat, margarine, meat-free dinner, milk, pizza, poultry, salmon, sausage, shrimp, sliced ham, tilapia, and vegetable oil. Using Diet History Questionnaire II, we calculated the PCB dietary exposure in mothers and children participating in the AESOP Study in East Chicago, Indiana, and Columbus Junction, Iowa. Salmon had the highest concentration followed by canned tuna, but fish is a minor contributor to exposure. Other animal proteins are more important sources of PCB dietary exposure in this study population. Despite the inclusion of few congeners and food types in previous studies, we found evidence of a decline in PCB concentrations over the last 20 years. We also found strong associations of PCB congener distributions with Aroclors in most foods and found manufacturing byproduct PCBs, including PCB11, in tilapia and catfish. The reduction in PCB levels in food indicates that dietary exposure is comparable to PCB inhalation exposures reported for the same study population.
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Affiliation(s)
- Panithi Saktrakulkla
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA
- Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA
| | - Tuo Lan
- Department of Occupational and Environmental Health, College of Public Health, and The University of Iowa, Iowa City, IA, 52242, USA
| | - Jason Hua
- Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA
| | - Rachel F Marek
- Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA
| | - Peter S Thorne
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA
- Department of Occupational and Environmental Health, College of Public Health, and The University of Iowa, Iowa City, IA, 52242, USA
| | - Keri C Hornbuckle
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA
- Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA
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11
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Matelski L, Keil Stietz KP, Sethi S, Taylor SL, Van de Water J, Lein PJ. The influence of sex, genotype, and dose on serum and hippocampal cytokine levels in juvenile mice developmentally exposed to a human-relevant mixture of polychlorinated biphenyls. Curr Res Toxicol 2020; 1:85-103. [PMID: 34296199 PMCID: PMC8294704 DOI: 10.1016/j.crtox.2020.09.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Polychlorinated biphenyls (PCBs) are pervasive environmental contaminants implicated as risk factors for neurodevelopmental disorders (NDDs). Immune dysregulation is another NDD risk factor, and developmental PCB exposures are associated with early life immune dysregulation. Studies of the immunomodulatory effects of PCBs have focused on the higher-chlorinated congeners found in legacy commercial mixtures. Comparatively little is known about the immune effects of contemporary, lower-chlorinated PCBs. This is a critical data gap given recent reports that lower-chlorinated congeners comprise >70% of the total PCB burden in serum of pregnant women enrolled in the MARBLES study who are at increased risk for having a child with an NDD. To examine the influence of PCBs, sex, and genotype on cytokine levels, mice were exposed throughout gestation and lactation to a PCB mixture in the maternal diet, which was based on the 12 most abundant PCBs in sera from MARBLES subjects. Using multiplex array, cytokines were quantified in the serum and hippocampus of weanling mice expressing either a human gain-of-function mutation in ryanodine receptor 1 (T4826I mice), a human CGG premutation repeat expansion in the fragile X mental retardation gene 1 (CGG mice), or both mutations (DM mice). Congenic wildtype (WT) mice were used as controls. There were dose-dependent effects of PCB exposure on cytokine concentrations in the serum but not hippocampus. Differential effects of genotype were observed in the serum and hippocampus. Hippocampal cytokines were consistently elevated in T4826I mice and also in WT animals for some cytokines compared to CGG and DM mice, while serum cytokines were usually elevated in the mutant genotypes compared to the WT group. Males had elevated levels of 19 cytokines in the serum and 4 in the hippocampus compared to females, but there were also interactions between sex and genotype for 7 hippocampal cytokines. Only the chemokine CCL5 in the serum showed an interaction between PCB dose, genotype, and sex. Collectively, these findings indicate differential influences of PCB exposure and genotype on cytokine levels in serum and hippocampal tissue of weanling mice. These results suggest that developmental PCB exposure has chronic effects on baseline serum, but not hippocampal, cytokine levels in juvenile mice.
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Affiliation(s)
- Lauren Matelski
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA
| | - Kimberly P. Keil Stietz
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA
| | - Sunjay Sethi
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA
| | - Sandra L. Taylor
- Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, School of Medicine, Davis, CA 95616, USA
| | - Judy Van de Water
- MIND Institute, University of California, Davis, School of Medicine, Sacramento, CA 95817, USA,Division of Rheumatology, Allergy, and Clinical Immunology, Department of Internal Medicine, University of California, Davis, School of Medicine, Davis, CA 95616, USA
| | - Pamela J. Lein
- Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, Davis, CA 95616, USA,MIND Institute, University of California, Davis, School of Medicine, Sacramento, CA 95817, USA,Corresponding author at: Department of Molecular Biosciences, University of California, Davis, School of Veterinary Medicine, 1089 Veterinary Medicine Drive, Davis, CA 95616, USA.
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12
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Liu J, Tan Y, Song E, Song Y. A Critical Review of Polychlorinated Biphenyls Metabolism, Metabolites, and Their Correlation with Oxidative Stress. Chem Res Toxicol 2020; 33:2022-2042. [DOI: 10.1021/acs.chemrestox.0c00078] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Jing Liu
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang 550025, People’s Republic of China
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
| | - Ya Tan
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
| | - Erqun Song
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
| | - Yang Song
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
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13
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Grimm FA, Klaren WD, Li X, Lehmler HJ, Karmakar M, Robertson LW, Chiu WA, Rusyn I. Cardiovascular Effects of Polychlorinated Biphenyls and Their Major Metabolites. ENVIRONMENTAL HEALTH PERSPECTIVES 2020; 128:77008. [PMID: 32701041 PMCID: PMC7377239 DOI: 10.1289/ehp7030] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND Xenobiotic metabolism is complex, and accounting for bioactivation and detoxification processes of chemicals remains among the most challenging aspects for decision making with in vitro new approach methods data. OBJECTIVES Considering the physiological relevance of human organotypic culture models and their utility for high-throughput screening, we hypothesized that multidimensional chemical-biological profiling of chemicals and their major metabolites is a sensible alternative for the toxicological characterization of parent molecules vs. metabolites in vitro. METHODS In this study, we tested 25 polychlorinated biphenyls (PCBs) [PCB 3, 11, 52, 126, 136, and 153 and their relevant metabolites (hydroxylated, methoxylated, sulfated, and quinone)] in concentration-response (10 nM-100μM) for effects in human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) and endothelial cells (ECs) (iPSC-derived and HUVECs). Functional phenotypic end points included effects on beating parameters and intracellular Ca2+ flux in CMs and inhibition of tubulogenesis in ECs. High-content imaging was used to evaluate cytotoxicity, mitochondrial integrity, and oxidative stress. RESULTS Data integration of a total of 19 physicochemical descriptors and 36 in vitro phenotypes revealed that chlorination status and metabolite class are strong predictors of the in vitro cardiovascular effects of PCBs. Oxidation of PCBs, especially to di-hydroxylated and quinone metabolites, was associated with the most pronounced effects, whereas sulfation and methoxylation of PCBs resulted in diminished bioactivity. DISCUSSION Risk characterization analysis showed that although in vitro derived effective concentrations exceeded the levels measured in the general population, risks cannot be ruled out due to the potential for population variability in susceptibility and the need to fill data gaps using read-across approaches. This study demonstrated a strategy for how in vitro data can be used to characterize human health risks from PCBs and their metabolites. https://doi.org/10.1289/EHP7030.
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Affiliation(s)
- Fabian A. Grimm
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - William D. Klaren
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa, USA
| | - Moumita Karmakar
- Department of Statistics, College of Science, Texas A&M University, College Station, Texas, USA
| | - Larry W. Robertson
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa, USA
| | - Weihsueh A. Chiu
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
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14
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Wójcik A, Perczyk P, Wydro P, Broniatowski M. Dichlorobiphenyls and chlorinated benzoic acids – Emergent soil pollutants in model bacterial membranes. Langmuir monolayer and Grazing Incidence X-ray Diffraction studies. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112997] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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15
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Dhakal R, Li X, Parkin SR, Lehmler HJ. Synthesis of mono- and dimethoxylated polychlorinated biphenyl derivatives starting from fluoroarene derivatives. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:8905-8925. [PMID: 31893358 PMCID: PMC7098850 DOI: 10.1007/s11356-019-07133-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 11/20/2019] [Indexed: 06/10/2023]
Abstract
Polychlorinated biphenyls (PCBs) are environmental pollutants implicated in a variety of adverse health effects, including cancer and noncancer diseases in animals and humans. PCBs are metabolized to hydroxylated compounds, and some of these PCB metabolites are more toxic than the parent PCBs. Unfortunately, most PCB metabolites needed for toxicological studies are not available from commercial sources. Moreover, it is challenging to synthesize PCB metabolites because starting materials with suitable substitution patterns are not readily available. Here, we report the novel synthesis of a variety of mono- and dimethoxyarene derivatives from commercially available fluoroarenes via nucleophilic aromatic substitution with sodium methoxide. This reaction provided good to excellent yields of the desired methoxylated products. Suzuki coupling of selected mono- and dimethoxy haloarenes with chlorinated phenylboronic acids yielded methoxylated derivatives of PCB 11, 12, 25, 35, and 36 in low to good yields. Crystal structures of 3,3'-dichloro-2,5-dimethoxy-1,1'-biphenyl and 3',5-dichloro-2,3-dimethoxy-1,1'-biphenyl confirmed the substitution pattern of both compounds. This synthesis strategy provides straightforward access to a range of mono- and dimethoxylated PCB derivatives that were not readily accessible previously.
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Affiliation(s)
- Ram Dhakal
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA
| | - Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA
| | - Sean R Parkin
- Department of Chemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA.
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16
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Saktrakulkla P, Dhakal RC, Lehmler HJ, Hornbuckle KC. A semi-target analytical method for quantification of OH-PCBs in environmental samples. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020. [PMID: 31359319 DOI: 10.25820/036e-b439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Hydroxylated polychlorinated biphenyls (OH-PCBs) are oxidative metabolites of PCBs and residuals found in original Aroclors. OH-PCBs are known to play a role as genotoxicants, carcinogens, and hormone disruptors, and therefore it is important to quantify their presence in human tissues, organisms, and environmental matrices. Of 837 possible mono-OH-PCBs congeners, there are only ~ 70 methoxylated PCB (MeO-PCB) standards commercially available. Hence, a semi-target analytical method is needed for unknown OH-PCBs. The mass concentrations of these unknowns are sometimes determined by assuming the peak responses of other available compounds. This can bias the results due to the choices and availabilities of standards. To overcome this issue, we investigated the peak responses of all commercially available MeO-PCB standards with gas chromatography (GC) coupling with triple quadrupole (QqQ) mass spectrometry (MS) system, with positive electron impact (EI) ionization at 20-70 eV in selected ion monitoring (SIM) mode. We found correlations between the relative peak responses (RRFs) and the number of chlorine (#Cl) in the molecules of MeO-PCBs. Among the studied models, the quadratic regression of #Cl is the most suitable model in the RRF prediction (RRF = β1 × #Cl^2 + β0) when the peak responses are captured at 30 eV. We evaluated the performance of the model by analyzing 12 synthesized MeO-PCB standards and a PCB-contaminated sediment collected from a wastewater lagoon. We further demonstrate the utility of the model using a different chromatography column and GC-EI-MS system. We found the method and associated model to be sufficiently simple, accurate, and versatile for use in quantifying OH-PCBs in complex environmental samples.
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Affiliation(s)
- Panithi Saktrakulkla
- Graduate Program in Human Toxicology, Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA
| | - Ram C Dhakal
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, 52242, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, 52242, USA
| | - Keri C Hornbuckle
- Graduate Program in Human Toxicology, Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA.
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17
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Saktrakulkla P, Dhakal RC, Lehmler HJ, Hornbuckle KC. A semi-target analytical method for quantification of OH-PCBs in environmental samples. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:8859-8871. [PMID: 31359319 PMCID: PMC6986979 DOI: 10.1007/s11356-019-05775-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/17/2019] [Indexed: 04/16/2023]
Abstract
Hydroxylated polychlorinated biphenyls (OH-PCBs) are oxidative metabolites of PCBs and residuals found in original Aroclors. OH-PCBs are known to play a role as genotoxicants, carcinogens, and hormone disruptors, and therefore it is important to quantify their presence in human tissues, organisms, and environmental matrices. Of 837 possible mono-OH-PCBs congeners, there are only ~ 70 methoxylated PCB (MeO-PCB) standards commercially available. Hence, a semi-target analytical method is needed for unknown OH-PCBs. The mass concentrations of these unknowns are sometimes determined by assuming the peak responses of other available compounds. This can bias the results due to the choices and availabilities of standards. To overcome this issue, we investigated the peak responses of all commercially available MeO-PCB standards with gas chromatography (GC) coupling with triple quadrupole (QqQ) mass spectrometry (MS) system, with positive electron impact (EI) ionization at 20-70 eV in selected ion monitoring (SIM) mode. We found correlations between the relative peak responses (RRFs) and the number of chlorine (#Cl) in the molecules of MeO-PCBs. Among the studied models, the quadratic regression of #Cl is the most suitable model in the RRF prediction (RRF = β1 × #Cl^2 + β0) when the peak responses are captured at 30 eV. We evaluated the performance of the model by analyzing 12 synthesized MeO-PCB standards and a PCB-contaminated sediment collected from a wastewater lagoon. We further demonstrate the utility of the model using a different chromatography column and GC-EI-MS system. We found the method and associated model to be sufficiently simple, accurate, and versatile for use in quantifying OH-PCBs in complex environmental samples.
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Affiliation(s)
- Panithi Saktrakulkla
- Graduate Program in Human Toxicology, Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA
| | - Ram C Dhakal
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, 52242, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, 52242, USA
| | - Keri C Hornbuckle
- Graduate Program in Human Toxicology, Department of Civil and Environmental Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA, 52242, USA.
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18
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Rodenburg LA, Delistraty DA. Alterations in fingerprints of polychlorinated biphenyls in benthic biota at the Portland Harbor Superfund Site (Oregon, USA) suggest metabolism. CHEMOSPHERE 2019; 223:74-82. [PMID: 30771650 DOI: 10.1016/j.chemosphere.2019.02.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 02/05/2019] [Accepted: 02/09/2019] [Indexed: 06/09/2023]
Abstract
In order to understand the sources and fate of polychlorinated biphenyls (PCBs) in several species of benthic biota, including clams (Corbicula fluminea), oligochaetes (Lumbriculus variegatus), and mussels (Margaritifera falcata and Anodonta nuttalliana) at the Portland Harbor Superfund Site (PHSS), their congener fingerprints were examined. First, diagnostic ratios of congeners known to be metabolizable vs. recalcitrant in the cytochrome P450 (CYP) pathway were significantly lower in biota than in its co-located sediment, indicating metabolism may have occurred. Next, the congener patterns were analyzed using Positive Matrix Factorization (PMF). The dominant fingerprint (by mass) in benthic biota is related to Aroclor 1260 but displays differences in the fingerprint that are consistent with weathering via absorption, distribution, metabolism, and excretion (ADME). This fingerprint is similar to one isolated from PCBs in fish from Washington State, indicative of common metabolic pathways and consistent with CYP metabolism. When metabolism is taken into account, the spatial distribution of the PMF-isolated PCB fingerprints in biota matches well with those from co-located sediment samples, suggesting that the same mix of sources at one location partitions into biota and sediment. In accordance to their higher hydrophobicity, higher molecular weight (MW) PCB formulations were proportionately more abundant in biota than in sediment, although low MW PCBs (e.g., PCBs 4 and 11) do bioaccumulate in benthic organisms and should not be ignored in risk assessment efforts. Finally, fingerprinting suggests potential reasons why lab-based and field-based biota-sediment accumulation factors (BSAFs) differ substantially for bivalves.
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Affiliation(s)
- Lisa A Rodenburg
- Department of Environmental Sciences, Rutgers University, 14 College Farm, Road, New Brunswick, NJ 08901, USA.
| | - Damon A Delistraty
- Washington State Department of Ecology, North 4601 Monroe Street, Spokane, WA 99205, USA
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19
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Vasko T, Hoffmann J, Gostek S, Schettgen T, Quinete N, Preisinger C, Kraus T, Ziegler P. Telomerase gene expression bioassays indicate metabolic activation of genotoxic lower chlorinated polychlorinated biphenyls. Sci Rep 2018; 8:16903. [PMID: 30443001 PMCID: PMC6237825 DOI: 10.1038/s41598-018-35043-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/29/2018] [Indexed: 12/18/2022] Open
Abstract
Polychlorinated biphenyls (PCBs) are ubiquitously occurring pollutants with different chemical and toxicological properties. In this study we evaluated blood plasma samples of two PCB-exposed cohorts for their ability to alter telomerase (hTERT) gene expression. Blood plasma from PCB-exposed individuals inhibited hTERT expression depending solely on the concentration of lower chlorinated PCBs, with the lowest observed adverse effect level (LOAEL) at a plasma concentration between 0.5 and 2 µg/L of LC PCBs. Individual OH-metabolites derived from the WHO indicator congeners PCB 28 and PCB 101 mimicked these effects on hTERT expression in vitro with high toxicity, including DNA damage. However, by the combination of different OH-metabolites, the bio effective PCB concentration was reduced and the respective effects on hTERT expression could be increased. At a concentration which showed no toxic activity in MTT assay, hTERT inhibition reflected the interference of OH-PCBs with the mitochondrial respiratory chain, which could lead to the production of reactive oxygen species (ROS). As individual OH-metabolites already showed a much stronger inhibition of hTERT gene expression at a lower concentration than their parental compounds, the hTERT gene expression bioassay described in this study seems to indicate metabolic activation of LC PCBs rather than the mere effect of LC PCBs on their own. In summary, this study provides dose-response linkages between effects of lower chlorinated PCBs and their concentrations in human plasma.
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Affiliation(s)
- Theresa Vasko
- Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, Aachen, Germany
| | - Jenny Hoffmann
- Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, Aachen, Germany
| | - Sonja Gostek
- Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, Aachen, Germany
| | - Thomas Schettgen
- Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, Aachen, Germany
| | - Natalia Quinete
- Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, Aachen, Germany.,Southeast Environmental Research Center, Florida International University Florida, Florida, USA
| | | | - Thomas Kraus
- Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, Aachen, Germany
| | - Patrick Ziegler
- Institute for Occupational, Social and Environmental Medicine, RWTH Aachen University, Aachen, Germany.
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20
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Alam S, Carter GS, Krager KJ, Li X, Lehmler HJ, Aykin-Burns N. PCB11 Metabolite, 3,3'-Dichlorobiphenyl-4-ol, Exposure Alters the Expression of Genes Governing Fatty Acid Metabolism in the Absence of Functional Sirtuin 3: Examining the Contribution of MnSOD. Antioxidants (Basel) 2018; 7:antiox7090121. [PMID: 30223548 PMCID: PMC6162768 DOI: 10.3390/antiox7090121] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 09/10/2018] [Accepted: 09/13/2018] [Indexed: 01/12/2023] Open
Abstract
Although the production of polychlorinated biphenyls (PCBs) is prohibited, the inadvertent production of certain lower-chlorinated PCB congeners still threatens human health. We and others have identified 3,3’-dichlorobiphenyl (PCB11) and its metabolite, 3,3’-dichlorobiphenyl-4-ol (4OH-PCB11), in human blood, and there is a correlation between exposure to this metabolite and mitochondrial oxidative stress in mammalian cells. Here, we evaluated the downstream effects of 4OH-PCB11 on mitochondrial metabolism and function in the presence and absence of functional Sirtuin 3 (SIRT3), a mitochondrial fidelity protein that protects redox homeostasis. A 24 h exposure to 3 μM 4OH-PCB11 significantly decreased the cellular growth and mitochondrial membrane potential of SIRT3-knockout mouse embryonic fibroblasts (MEFs). Only wild-type cells demonstrated an increase in Manganese superoxide dismutase (MnSOD) activity in response to 4OH-PCB11–induced oxidative injury. This suggests the presence of a SIRT3-mediated post-translational modification to MnSOD, which was impaired in SIRT3-knockout MEFs, which counters the PCB insult. We found that 4OH-PCB11 increased mitochondrial respiration and endogenous fatty-acid oxidation-associated oxygen consumption in SIRT3-knockout MEFs; this appeared to occur because the cells exhausted their reserve respiratory capacity. To determine whether these changes in mitochondrial respiration were accompanied by similar changes in the regulation of fatty acid metabolism, we performed quantitative real-time polymerase chain reaction (qRT-PCR) after a 24 h treatment with 4OH-PCB11. In SIRT3-knockout MEFs, 4OH-PCB11 significantly increased the expression of ten genes controlling fatty acid biosynthesis, metabolism, and transport. When we overexpressed MnSOD in these cells, the expression of six of these genes returned to the baseline level, suggesting that the protective role of SIRT3 against 4OH-PCB11 is partially governed by MnSOD activity.
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Affiliation(s)
- Sinthia Alam
- Division of Radiation Health, Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
| | - Gwendolyn S Carter
- Division of Radiation Health, Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
| | - Kimberly J Krager
- Division of Radiation Health, Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
| | - Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA 52242, USA.
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA 52242, USA.
| | - Nukhet Aykin-Burns
- Division of Radiation Health, Department of Pharmaceutical Sciences, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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21
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Li X, Holland EB, Feng W, Zheng J, Dong Y, Pessah IN, Duffel MW, Robertson LW, Lehmler HJ. Authentication of synthetic environmental contaminants and their (bio)transformation products in toxicology: polychlorinated biphenyls as an example. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16508-16521. [PMID: 29322390 PMCID: PMC6015536 DOI: 10.1007/s11356-017-1162-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 12/26/2017] [Indexed: 04/15/2023]
Abstract
Toxicological studies use "specialty chemicals" and, thus, should assess and report both identity and degree of purity (homogeneity) of the chemicals (or toxicants) under investigation to ensure that other scientists can replicate experimental results. Although detailed reporting criteria for the synthesis and characterization of organic compounds have been established by organic chemistry journals, such criteria are inconsistently applied to the chemicals used in toxicological studies. Biologically active trace impurities may lead to incorrect conclusions about the chemical entity responsible for a biological response, which in turn may confound risk assessment. Based on our experience with the synthesis of PCBs and their metabolites, we herein propose guidelines for the "authentication" of synthetic PCBs and, by extension, other organic toxicants, and provide a checklist for documenting the authentication of toxicants reported in the peer-reviewed literature. The objective is to expand guidelines proposed for different types of biomedical and preclinical studies to include a thorough authentication of specialty chemicals, such as PCBs and their derivatives, with the goal of ensuring transparent and open reporting of scientific results in toxicology and the environmental health sciences.
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Affiliation(s)
- Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA
| | - Erika B Holland
- Department of Biological Sciences, California State University of Long Beach, Long Beach, CA, USA
| | - Wei Feng
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Jing Zheng
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Yao Dong
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Isaac N Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Michael W Duffel
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, USA
| | - Larry W Robertson
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA.
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22
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Pěnčíková K, Svržková L, Strapáčová S, Neča J, Bartoňková I, Dvořák Z, Hýžďalová M, Pivnička J, Pálková L, Lehmler HJ, Li X, Vondráček J, Machala M. In vitro profiling of toxic effects of prominent environmental lower-chlorinated PCB congeners linked with endocrine disruption and tumor promotion. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 237:473-486. [PMID: 29518658 PMCID: PMC5908724 DOI: 10.1016/j.envpol.2018.02.067] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/20/2018] [Accepted: 02/20/2018] [Indexed: 05/18/2023]
Abstract
The mechanisms contributing to toxic effects of airborne lower-chlorinated PCB congeners (LC-PCBs) remain poorly characterized. We evaluated in vitro toxicities of environmental LC-PCBs found in both indoor and outdoor air (PCB 4, 8, 11, 18, 28 and 31), and selected hydroxylated metabolites of PCB 8, 11 and 18, using reporter gene assays, as well as other functional cellular bioassays. We focused on processes linked with endocrine disruption, tumor promotion and/or regulation of transcription factors controlling metabolism of both endogenous compounds and xenobiotics. The tested LC-PCBs were found to be mostly efficient anti-androgenic (within nanomolar - micromolar range) and estrogenic (at micromolar concentrations) compounds, as well as inhibitors of gap junctional intercellular communication (GJIC) at micromolar concentrations. PCB 8, 28 and 31 were found to partially inhibit the aryl hydrocarbon receptor (AhR)-mediated activity. The tested LC-PCBs were also partial constitutive androstane receptor (CAR) and pregnane X receptor (PXR) agonists, with PCB 4, 8 and 18 being the most active compounds. They were inactive towards other nuclear receptors, such as vitamin D receptor, thyroid receptor α, glucocorticoid receptor or peroxisome proliferator-activated receptor γ. We found that only PCB 8 contributed to generation of oxidative stress, while all tested LC-PCBs induced arachidonic acid release (albeit without further modulations of arachidonic acid metabolism) in human lung epithelial cells. Importantly, estrogenic effects of hydroxylated (OH-PCB) metabolites of LC-PCBs (4-OH-PCB 8, 4-OH-PCB 11 and 4'-OH-PCB 18) were higher than those of the parent PCBs, while their other toxic effects were only slightly altered or suppressed. This suggested that metabolism may alter toxicity profiles of LC-PCBs in a receptor-specific manner. In summary, anti-androgenic and estrogenic activities, acute inhibition of GJIC and suppression of the AhR-mediated activity were found to be the most relevant modes of action of airborne LC-PCBs, although they partially affected also additional cellular targets.
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Affiliation(s)
- Kateřina Pěnčíková
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 70, 62100 Brno, Czech Republic
| | - Lucie Svržková
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 70, 62100 Brno, Czech Republic
| | - Simona Strapáčová
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 70, 62100 Brno, Czech Republic
| | - Jiří Neča
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 70, 62100 Brno, Czech Republic
| | - Iveta Bartoňková
- Department of Cell Biology and Genetics, Faculty of Science, Šlechtitelů 11, Palacký University, 78371 Olomouc, Czech Republic
| | - Zdeněk Dvořák
- Department of Cell Biology and Genetics, Faculty of Science, Šlechtitelů 11, Palacký University, 78371 Olomouc, Czech Republic
| | - Martina Hýžďalová
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 70, 62100 Brno, Czech Republic; Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic
| | - Jakub Pivnička
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic
| | - Lenka Pálková
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 70, 62100 Brno, Czech Republic
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, 52242, IA, USA
| | - Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, 52242, IA, USA
| | - Jan Vondráček
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic.
| | - Miroslav Machala
- Department of Chemistry and Toxicology, Veterinary Research Institute, Hudcova 70, 62100 Brno, Czech Republic.
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23
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Parker VS, Squirewell EJ, Lehmler HJ, Robertson LW, Duffel MW. Hydroxylated and sulfated metabolites of commonly occurring airborne polychlorinated biphenyls inhibit human steroid sulfotransferases SULT1E1 and SULT2A1. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2018; 58:196-201. [PMID: 29408762 PMCID: PMC6078096 DOI: 10.1016/j.etap.2018.01.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 01/24/2018] [Indexed: 05/20/2023]
Abstract
Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants that are associated with varied adverse health effects. Lower chlorinated PCBs are prevalent in indoor and outdoor air and can be metabolized to their hydroxylated derivatives (OH-PCBs) followed by sulfation to form PCB sulfates. Sulfation is also a means of signal termination for steroid hormones. The human estrogen sulfotransferase (SULT1E1) and alcohol/hydroxysteroid sulfotransferase (SULT2A1) catalyze the formation of steroid sulfates that are inactive at steroid hormone receptors. We investigated the inhibition of SULT1E1 (IC50s ranging from 7.2 nM to greater than 10 μM) and SULT2A1 (IC50s from 1.3 μM to over 100 μM) by five lower-chlorinated OH-PCBs and their corresponding PCB sulfates relevant to airborne PCB-exposure. Several congeners of lower chlorinated OH-PCBs relevant to airborne PCB exposures were potent inhibitors of SULT1E1 and SULT2A1 and thus have the potential to disrupt regulation of intracellular concentrations of the receptor-active steroid substrates for these enzymes.
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Affiliation(s)
- Victoria S Parker
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, United States
| | - Edwin J Squirewell
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, United States
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, United States
| | - Larry W Robertson
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, United States
| | - Michael W Duffel
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, United States.
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24
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Li X, Zhong Y, Zhao C. Trypsin Binding with Copper Ions Scavenges Superoxide: Molecular Dynamics-Based Mechanism Investigation. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15010139. [PMID: 29342974 PMCID: PMC5800238 DOI: 10.3390/ijerph15010139] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 12/27/2017] [Accepted: 01/07/2018] [Indexed: 12/18/2022]
Abstract
Trypsin is a serine protease, which has been proved to be a novel superoxide scavenger. The burst of superoxide induced by polychlorinated biphenyls can be impeded by trypsin in both wild type and sod knockout mutants of Escherichia coli. The experimental results demonstrated that the activities of superoxide scavenging of trypsin were significantly accelerated by Cu ions. Also, with the addition of Cu ions, a new β-sheet (β7) transited from a random coil in the Cu(II)-trypsin (TP) system, which was favorable for the formation of more contacts with other sheets of trypsin. Residue–residue network analysis and the porcupine plots proved that the Cu ion in trypsin strengthened some native interactions among residues, which ultimately resulted in much greater stability of the Cu(II)-TP system. Moreover, compact and stable trypsin structures with Cu ions might be responsible for significantly provoking the activity of superoxide scavenging.
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Affiliation(s)
- Xin Li
- College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China.
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, Lanzhou University, Lanzhou 730000, China.
| | - Yongliang Zhong
- College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China.
| | - Chunyan Zhao
- School of Pharmacy, Lanzhou University, Lanzhou 730000, China.
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25
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Sethi S, Keil KP, Chen H, Hayakawa K, Li X, Lin Y, Lehmler HJ, Puschner B, Lein PJ. Detection of 3,3'-Dichlorobiphenyl in Human Maternal Plasma and Its Effects on Axonal and Dendritic Growth in Primary Rat Neurons. Toxicol Sci 2017; 158:401-411. [PMID: 28510766 PMCID: PMC5837364 DOI: 10.1093/toxsci/kfx100] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
3,3'-Dichlorobiphenyl (PCB 11), a byproduct of pigment production, is increasingly detected in environmental samples. While more highly chlorinated PCB congeners are known developmental neurotoxicants, nothing is known about the potential developmental neurotoxicity of PCB 11. To address this critical data gap, we measured PCB 11 levels in human maternal plasma and quantified the effects of PCB 11 and its major metabolites on morphometric parameters of neuronal connectivity in cultured primary neurons. Mass spectrometry analyses of plasma from 241 pregnant women enrolled in the MARBLES study (University of California, Davis) detected PCB 11 in all samples at concentrations ranging from 0.005 to 1.717 ng/ml. Morphometric analyses of primary neuron-glia co-cultures dissociated from the neocortices or hippocampi of neonatal Sprague Dawley rats exposed to vehicle or concentrations ranging from 1 attamolar (aM) to 1 micromolar (µM) of PCB 11, OH-PCB 11, or PCB 11 sulfate indicated that PCB 11 and both metabolites significantly increased axonal and dendritic growth in cortical and hippocampal pyramidal neurons. PCB 11 significantly altered neuronal morphogenesis at concentrations as low as 1 femtomolar (fM), which is ∼0.22 ng/ml. These data suggest the potential for the developing human brain to be exposed to PCB 11, and demonstrate that environmentally relevant levels of PCB 11 alter axonal and dendritic growth in neuronal cell types critically involved in cognitive and higher-order behaviors. These findings identify PCB 11 as a potential environmental risk factor for adverse neurodevelopmental outcomes in humans.
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Affiliation(s)
- Sunjay Sethi
- Department of Molecular Biosciences, University of California, Davis, California 95616
| | - Kimberly P. Keil
- Department of Molecular Biosciences, University of California, Davis, California 95616
| | - Hao Chen
- Department of Molecular Biosciences, University of California, Davis, California 95616
| | - Keri Hayakawa
- Department of Molecular Biosciences, University of California, Davis, California 95616
| | - Xueshu Li
- Department of Occupational & Environmental Health, University of Iowa, Iowa City, Iowa 52242
| | - Yanping Lin
- Department of Molecular Biosciences, University of California, Davis, California 95616
| | - Hans-Joachim Lehmler
- Department of Occupational & Environmental Health, University of Iowa, Iowa City, Iowa 52242
| | - Birgit Puschner
- Department of Molecular Biosciences, University of California, Davis, California 95616
| | - Pamela J. Lein
- Department of Molecular Biosciences, University of California, Davis, California 95616
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26
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Quinete N, Esser A, Kraus T, Schettgen T. PCB 28 metabolites elimination kinetics in human plasma on a real case scenario: Study of hydroxylated polychlorinated biphenyl (OH-PCB) metabolites of PCB 28 in a highly exposed German Cohort. Toxicol Lett 2017; 276:100-107. [DOI: 10.1016/j.toxlet.2017.05.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 05/17/2017] [Accepted: 05/23/2017] [Indexed: 02/02/2023]
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27
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Batang ZB, Alikunhi N, Gochfeld M, Burger J, Al-Jahdali R, Al-Jahdali H, Aziz MAM, Al-Jebreen D, Al-Suwailem A. Congener-specific levels and patterns of polychlorinated biphenyls in edible fish tissue from the central Red Sea coast of Saudi Arabia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 572:915-925. [PMID: 27522293 DOI: 10.1016/j.scitotenv.2016.07.207] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 07/29/2016] [Accepted: 07/29/2016] [Indexed: 05/11/2023]
Abstract
All 209 congeners of polychlorinated biphenyls (PCBs) in edible fish tissue from the central Red Sea coast (Jeddah region) of Saudi Arabia were analyzed by isotope dilution high-resolution gas chromatography-mass spectrometry. The upper-bound total PCB (ΣPCB) levels in nine commonly consumed fish species from three areas were 0.2-82.5ng/g wet weight (17-8450ng/g lipid weight), which were at the lower end of reported global range and far below international tolerance limits (500-3000ng/g ww). Dioxin-like congeners contributed up to 12.8% (mean 6.5%) to ΣPCB in tissue samples, with the total PCB toxic equivalencies (TEQs) at a tolerable range (0.05-2.6pgTEQ/g ww or 2-238pgTEQ/g lw) for all species. PCB profiles were dominated by moderately chlorinated homologs, mainly hexachlorobiphenyls, but less chlorinated congeners were also consistently elevated, notably in Siganus rivulatus (Area III) and Mugil cephalus (Area I). It remains to be ascertained if the latter were breakdown products or due to fresh inputs. The top congeners based on dominance by both occurrence and abundance were identified as potential markers of ΣPCB in fish tissue, which can be used for future selective biomonitoring in case of reasonable constraints on full congener approach.
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Affiliation(s)
- Zenon B Batang
- Coastal and Marine Resources Core Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia.
| | - Nabeel Alikunhi
- Coastal and Marine Resources Core Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Michael Gochfeld
- Environmental and Community Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
| | - Joanna Burger
- Division of Life Sciences, Rutgers University, Piscataway, NJ 08554, USA; Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ 08854, USA
| | - Ramzi Al-Jahdali
- Coastal and Marine Resources Core Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Haitham Al-Jahdali
- Coastal and Marine Resources Core Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Mohammed A M Aziz
- Directorate of Aquatic Environment, Ministry of Environment, Water and Agriculture, Riyadh 11564, Saudi Arabia
| | - Dalal Al-Jebreen
- Department of Nutrition and Food Science, Princess Nora bint Abdul Rahman University, Riyadh 11564, Saudi Arabia
| | - Abdulaziz Al-Suwailem
- Coastal and Marine Resources Core Laboratory, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
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28
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Eskenazi B, Rauch SA, Tenerelli R, Huen K, Holland NT, Lustig RH, Kogut K, Bradman A, Sjödin A, Harley KG. In utero and childhood DDT, DDE, PBDE and PCBs exposure and sex hormones in adolescent boys: The CHAMACOS study. Int J Hyg Environ Health 2016; 220:364-372. [PMID: 27876543 DOI: 10.1016/j.ijheh.2016.11.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/30/2016] [Accepted: 11/02/2016] [Indexed: 01/01/2023]
Abstract
Dichlorodiphenyltrichloroethane (DDT), polybrominated diphenyl ether (PBDE) flame retardants, and polychlorinated biphenyls (PCBs) are believed to be endocrine-disrupting chemicals (EDCs) in humans and animals. The purpose of this study is to examine the relationship of in utero and childhood exposure to these purported EDCs and reproductive hormones in adolescent boys who participated in CHAMACOS, an ongoing birth cohort in California's Salinas Valley. We measured o,p'- and p,p'-DDT, p,p'-DDE, PBDEs and PCBs in serum collected from mothers during pregnancy or at delivery and from their sons at 9 years. We measured concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and total testosterone (T) from 234 of their sons at 12 years. In adjusted models, we found that a 10-fold increase in maternal prenatal serum concentrations of BDE-153 was associated with a 22.2% increase (95% CI: 1.0, 47.9) in FSH, a 96.6% increase (95% CI: 35.7, 184.7) in LH, and a 92.4% increase (95% CI: 20.9, 206.2) increase in T. Similarly, BDE-100 concentrations were associated with increases in boys' LH levels. A 10-fold increase in total prenatal ΣPCBs was associated with a 64.5% increase (95% CI: 8.6, 149.0) in FSH, primarily driven by non- dioxin-like congeners. Boys' hormone levels were only marginally associated with prenatal DDT or DDE in primary models, but when boys' Tanner stage at age 12 was added to models, prenatal maternal DDT levels were associated with decreases in LH (adjusted percent change per 10-fold increase=-18.5%, 95% CI: -29.8, -5.4) and T (percent change=-18.2%, 95% CI: -30.2, -4.2) and DDE with LH (percent change=-18.3%, 95% CI: -32.9, -0.6). Exposures measured in the children's serum at 9 years also showed associations between BDE-153 and ΣPCBs. However, there is evidence that these associations appear to be mediated by child BMI. This study suggests associations on male hormones of 12year old boys related to exposure to certain EDC exposure prenatally. The implications on future reproductive function in puberty and adulthood should be determined.
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Affiliation(s)
- Brenda Eskenazi
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA.
| | - Stephen A Rauch
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA
| | - Rachel Tenerelli
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA
| | - Karen Huen
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA
| | - Nina T Holland
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA
| | - Robert H Lustig
- Department of Pediatrics, University of California, San Francisco, CA, USA
| | - Katherine Kogut
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA
| | - Asa Bradman
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA
| | - Andreas Sjödin
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Kim G Harley
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA, USA
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29
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Chai T, Cui F, Mu X, Yang Y, Qi S, Zhu L, Wang C, Qiu J. Stereoselective induction by 2,2',3,4',6-pentachlorobiphenyl in adult zebrafish (Danio rerio): Implication of chirality in oxidative stress and bioaccumulation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 215:66-76. [PMID: 27179325 DOI: 10.1016/j.envpol.2016.04.075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 04/18/2016] [Accepted: 04/21/2016] [Indexed: 06/05/2023]
Abstract
This study aimed to investigate the oxidative stress process and bioaccumulation the racemic/(-)-/(+)- 2,2',3,4',6-pentachlorobiphenyl were administered to adult zebrafish (Danio rerio) after prolonged exposure of 56-days uptake and 49-days depuration experiments. Stereoselective accumulation was observed in adult samples after racemic exposure as revealed by decreased enantiomer fractions. The two enantiomers of PCB91 accumulated at different rates with logBCFk values close to 3.7, suggesting that they were highly hazardous and persistent pollutants. Exposure to racemic/(-)-/(+)- PCB91 stereoselectively induced oxidative stress owing to changes in reactive oxygen species, malondialdehyde contents, antioxidant enzyme activities and gene expressions in brain and liver tissues. In addition, the stereoselective relationship between bioconcentration and oxidative stress were also presented in this study. Our findings might be helpful for elucidating the environmental risk of the two enantiomers of PCB91 that induce toxicity in aquatic organisms.
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Affiliation(s)
- Tingting Chai
- College of Science, China Agricultural University, Beijing 100193, China; Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture, Beijing 100081, China
| | - Feng Cui
- College of Science, China Agricultural University, Beijing 100193, China
| | - Xiyan Mu
- College of Science, China Agricultural University, Beijing 100193, China
| | - Yang Yang
- College of Science, China Agricultural University, Beijing 100193, China
| | - Suzhen Qi
- College of Science, China Agricultural University, Beijing 100193, China
| | - Lizhen Zhu
- College of Science, China Agricultural University, Beijing 100193, China
| | - Chengju Wang
- College of Science, China Agricultural University, Beijing 100193, China.
| | - Jing Qiu
- Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture, Beijing 100081, China.
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30
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AWAD ANDREWM, MARTINEZ ANDRES, MAREK RACHELF, HORNBUCKLE KERIC. Occurrence and Distribution of Two Hydroxylated Polychlorinated Biphenyl Congeners in Chicago Air. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2016; 3:47-51. [PMID: 30246046 PMCID: PMC6148743 DOI: 10.1021/acs.estlett.5b00337] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We measured hydroxylated polychlorinated biphenyls (OH-PCBs) in both gas and particulate phases in 30 Chicago air samples, the first report of OH-PCBs in environmental air samples. Concentrations of 2OH-PCB2 and 6OH-PCB2 in both phases were similar to PCB2 measured in the same samples, from non-detect to 11 pgm-3 and 12 ngg-1 for the gas and particulate phases, respectively. We found that OH-PCB2s sorbed more to particulates than did PCB2; seasonal variability was larger than spatial variability across Chicago; and partial pressure and temperature strongly correlated with the two OH-PCBs (p<0.0001). Similar 6OH-PCB2:2OH-PCB2 ratios were found in our air samples and Aroclors, suggesting that Aroclors are a legacy source of OH-PCB2s to the atmosphere and appear to be volatilizing proportionally to PCBs in Aroclors. Although degradation by the hydroxyl radical has been proposed as an efficient loss process for airborne PCBs, we found no evidence that this mechanism results in the formation of OH-PCB2s.
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Affiliation(s)
- ANDREW M. AWAD
- Department of Civil and Environmental Engineering IIHR-Hydroscience and
Engineering. The University of Iowa, Iowa City, IA 52242 USA
| | - ANDRES MARTINEZ
- Department of Civil and Environmental Engineering IIHR-Hydroscience and
Engineering. The University of Iowa, Iowa City, IA 52242 USA
| | - RACHEL F. MAREK
- Department of Civil and Environmental Engineering IIHR-Hydroscience and
Engineering. The University of Iowa, Iowa City, IA 52242 USA
| | - KERI C. HORNBUCKLE
- Department of Civil and Environmental Engineering IIHR-Hydroscience and
Engineering. The University of Iowa, Iowa City, IA 52242 USA
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31
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Wu X, Lehmler HJ. Effects of thiol antioxidants on the atropselective oxidation of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) by rat liver microsomes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:2081-8. [PMID: 26155892 PMCID: PMC4706823 DOI: 10.1007/s11356-015-4987-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 06/30/2015] [Indexed: 05/20/2023]
Abstract
Chiral polychlorinated biphenyl (PCB) congeners, such as PCB 136, are atropselectively metabolized to various hydroxylated PCB metabolites (HO-PCBs). The present study investigates the effect of two thiol antioxidants, glutathione and N-acetyl-cysteine (NAC), on profiles and chiral signatures of PCB 136 and its HO-PCB metabolites in rat liver microsomal incubations. Liver microsomes prepared from rats pretreated with phenobarbital were incubated with PCB 136 (5 μM) in the presence of the respective antioxidant (0-10 mM), and levels and chiral signatures of PCB 136 and its HO-PCB metabolites were determined. Three metabolites, 5-136 (2,2',3,3',6,6'-hexachlorobiphenyl-5-ol), 4-136 (2,2',3,3',6,6'-hexachlorobiphenyl-4-ol), and 4,5-136 (2,2',3,3',6,6'-hexachlorobiphenyl-4,5-diol), were detected in all incubations, with 5-136 being the major metabolite. Compared to microsomal incubations without antioxidant, levels of 4,5-136 increased with increasing antioxidant concentration, whereas levels of PCB 136 and both mono-HO-PCBs were not affected by the presence of either antioxidant. PCB 136, 4-136, and 5-136 displayed significant atropisomeric enrichment; however, the direction and extent of the atropisomeric enrichment was not altered in the presence of an antioxidant. Because 4,5-136 can either be conjugated to a sulfate or glucuronide metabolite that is readily excreted or further oxidized a potentially toxic PCB 136 quinone, the effect of both thiol antioxidants on 4,5-136 formation suggests that disruptions of glutathione homeostasis may alter the balance between both metabolic pathways and, thus, PCB 136 toxicity in vivo.
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Affiliation(s)
- Xianai Wu
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242-5000, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242-5000, USA.
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Vorkamp K. An overlooked environmental issue? A review of the inadvertent formation of PCB-11 and other PCB congeners and their occurrence in consumer products and in the environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 541:1463-1476. [PMID: 26490526 DOI: 10.1016/j.scitotenv.2015.10.019] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 10/05/2015] [Accepted: 10/05/2015] [Indexed: 05/25/2023]
Abstract
Polychlorinated biphenyls (PCBs) are banned from production and use in most countries as they are persistent organic pollutants (POPs) of concern for environment and health. Recent research has pointed at a new environment issue resulting from the inadvertent formation of PCBs in certain processes, in particular the pigment production. PCB-11 is a major by-product in these processes, but PCB-28, PCB-52, PCB-77 as well as the nonachlorinated PCBs and PCB-209 have been found in pigments and consumer products as well. In addition to environmental emissions via point sources, in particular related to industrial and municipal wastewater, atmospheric transport seems to be important for the global distribution of PCB-11. Thus, PCB-11 has also been detected in the polar regions. Worldwide air concentrations appear relatively uniform, but maxima have been found in urban and industrialised areas. Data on the uptake and accumulation of PCB-11 in the food chain are still inconclusive: Although food web studies do not show biomagnification, PCB-11 has been detected in humans. The human exposure might originate from the direct contact to consumer products as well as from the omnipresence of PCB-11 in the environment.
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Affiliation(s)
- Katrin Vorkamp
- Aarhus University, Department of Environmental Science, Frederiksborgvej 399, 4000 Roskilde, Denmark.
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Gore AC, Chappell VA, Fenton SE, Flaws JA, Nadal A, Prins GS, Toppari J, Zoeller RT. EDC-2: The Endocrine Society's Second Scientific Statement on Endocrine-Disrupting Chemicals. Endocr Rev 2015; 36:E1-E150. [PMID: 26544531 PMCID: PMC4702494 DOI: 10.1210/er.2015-1010] [Citation(s) in RCA: 1244] [Impact Index Per Article: 138.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 09/01/2015] [Indexed: 02/06/2023]
Abstract
The Endocrine Society's first Scientific Statement in 2009 provided a wake-up call to the scientific community about how environmental endocrine-disrupting chemicals (EDCs) affect health and disease. Five years later, a substantially larger body of literature has solidified our understanding of plausible mechanisms underlying EDC actions and how exposures in animals and humans-especially during development-may lay the foundations for disease later in life. At this point in history, we have much stronger knowledge about how EDCs alter gene-environment interactions via physiological, cellular, molecular, and epigenetic changes, thereby producing effects in exposed individuals as well as their descendants. Causal links between exposure and manifestation of disease are substantiated by experimental animal models and are consistent with correlative epidemiological data in humans. There are several caveats because differences in how experimental animal work is conducted can lead to difficulties in drawing broad conclusions, and we must continue to be cautious about inferring causality in humans. In this second Scientific Statement, we reviewed the literature on a subset of topics for which the translational evidence is strongest: 1) obesity and diabetes; 2) female reproduction; 3) male reproduction; 4) hormone-sensitive cancers in females; 5) prostate; 6) thyroid; and 7) neurodevelopment and neuroendocrine systems. Our inclusion criteria for studies were those conducted predominantly in the past 5 years deemed to be of high quality based on appropriate negative and positive control groups or populations, adequate sample size and experimental design, and mammalian animal studies with exposure levels in a range that was relevant to humans. We also focused on studies using the developmental origins of health and disease model. No report was excluded based on a positive or negative effect of the EDC exposure. The bulk of the results across the board strengthen the evidence for endocrine health-related actions of EDCs. Based on this much more complete understanding of the endocrine principles by which EDCs act, including nonmonotonic dose-responses, low-dose effects, and developmental vulnerability, these findings can be much better translated to human health. Armed with this information, researchers, physicians, and other healthcare providers can guide regulators and policymakers as they make responsible decisions.
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Affiliation(s)
- A C Gore
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
| | - V A Chappell
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
| | - S E Fenton
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
| | - J A Flaws
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
| | - A Nadal
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
| | - G S Prins
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
| | - J Toppari
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
| | - R T Zoeller
- Pharmacology and Toxicology (A.C.G.), College of Pharmacy, The University of Texas at Austin, Austin, Texas 78734; Division of the National Toxicology Program (V.A.C., S.E.F.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709; Department of Comparative Biosciences (J.A.F.), University of Illinois at Urbana-Champaign, Urbana, Illinois 61802; Institute of Bioengineering and CIBERDEM (A.N.), Miguel Hernandez University of Elche, 03202 Elche, Alicante, Spain; Departments of Urology, Pathology, and Physiology & Biophysics (G.S.P.), College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; Departments of Physiology and Pediatrics (J.T.), University of Turku and Turku University Hospital, 20520 Turku, Finland; and Biology Department (R.T.Z.), University of Massachusetts at Amherst, Amherst, Massachusetts 01003
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Identification of the retinoblastoma (Rb) gene and expression in response to environmental stressors in the intertidal copepod Tigriopus japonicus. Mar Genomics 2015; 24 Pt 3:387-96. [DOI: 10.1016/j.margen.2015.09.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 09/24/2015] [Accepted: 09/24/2015] [Indexed: 01/10/2023]
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Koh WX, Hornbuckle KC, Thorne PS. Human Serum from Urban and Rural Adolescents and Their Mothers Shows Exposure to Polychlorinated Biphenyls Not Found in Commercial Mixtures. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:8105-12. [PMID: 26053216 PMCID: PMC4774248 DOI: 10.1021/acs.est.5b01854] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Although polychlorinated biphenyls are no longer sold as commercial mixtures, they are still being produced through modern manufacturing processes. We have previously shown that non-Aroclor PCB 11 is prevalent in indoor and outdoor air and sediment and detected in human serum. Here we report the prevalence of non-Aroclor PCB congeners (≤0.20 wt % in Aroclor) in human serum collected from urban and rural adolescents and their mothers. We hypothesized that additional non-Aroclor congeners are present in serum. Sera were extracted and detected for 209 PCBs using gas chromatography-tandem mass spectrometry. A list of 70 non-Aroclor PCB congeners was determined by measurement of original Aroclors. PCB 11, 14, 35, and 209 are the major dominating and most frequently detected congeners. PCB 14 and 35 have not been previously reported for environmental matrices. Adolescents have significantly lower total non-Aroclor PCB concentrations than mothers in East Chicago (p < 0.001) and Columbus Junction (p = 0.008). There are significant differences in non-Aroclor PCBs between East Chicago community and Columbus Junction community (p < 0.001). Non-Aroclor PCBs represent an average of 10% (and up to 50%) of total PCBs measured in serum. An average of 50% (and up to 100%) of these concentrations may be attributed to aryl azo and phthalocyanine paint pigments.
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Affiliation(s)
- Wen Xin Koh
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Keri C. Hornbuckle
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa 52242, United States
- Department of Civil and Environmental Engineering, The University of Iowa, Iowa City, Iowa 52242, United States
- Corresponding Author: Phone: (319) 335-4216 (P.S.T.); 319-384-0789 (K.C.H.). Fax: (319) 384-4138 (P.S.T.); (319) 335-5660 (K.C.H.). (P.S.T.); (K.C.H.)
| | - Peter S. Thorne
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa 52242, United States
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
- Corresponding Author: Phone: (319) 335-4216 (P.S.T.); 319-384-0789 (K.C.H.). Fax: (319) 384-4138 (P.S.T.); (319) 335-5660 (K.C.H.). (P.S.T.); (K.C.H.)
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36
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Rodenburg LA, Delistraty D, Meng Q. Polychlorinated biphenyl congener patterns in fish near the Hanford Site (Washington State, USA). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2767-2775. [PMID: 25621866 DOI: 10.1021/es504961a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
It is well-known that absorption, distribution, metabolism, and excretion (ADME) processes in fish can alter polychlorinated biphenyl (PCB) congener patterns in fish, but these patterns have never been investigated using an advanced source-apportionment tool. In this work, PCB congener patterns in freshwater fish were examined with positive matrix factorization (PMF). PCB congeners were quantified via EPA Method 1668 in fillet and carcass of six species in four study areas in the Columbia River near the Hanford Site. Six factors were resolved with PMF2 software. Depletion and enhancement of PCB congeners in factors, relative to Aroclor 1254, suggested biotransformation (via cytochrome P450) and bioaccumulation in fish, respectively. Notable differences were observed among species and across study locations. For example, sturgeon and whitefish exhibited congener patterns consistent with Aroclor weathering, suggesting potential PCB metabolism in these species. In terms of location, average concentration of total PCBs for all species combined was significantly higher (P < 0.05) at Hanford 100 and 300 areas, relative to upriver and downriver study sites. Furthermore, a distinct PCB signature in sturgeon and whitefish, collected at Hanford study areas, suggests that Hanford is a unique PCB source.
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Affiliation(s)
- Lisa A Rodenburg
- Department of Environmental Science, Rutgers University , 14 College Farm Road, New Brunswick, New Jersey 08901, United States
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Grimm FA, Hu D, Kania-Korwel I, Lehmler HJ, Ludewig G, Hornbuckle KC, Duffel MW, Bergman A, Robertson LW. Metabolism and metabolites of polychlorinated biphenyls. Crit Rev Toxicol 2015; 45:245-72. [PMID: 25629923 PMCID: PMC4383295 DOI: 10.3109/10408444.2014.999365] [Citation(s) in RCA: 280] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 12/11/2014] [Indexed: 11/13/2022]
Abstract
Abstract The metabolism of polychlorinated biphenyls (PCBs) is complex and has an impact on toxicity, and thereby on the assessment of PCB risks. A large number of reactive and stable metabolites are formed in the processes of biotransformation in biota in general, and in humans in particular. The aim of this document is to provide an overview of PCB metabolism, and to identify the metabolites of concern and their occurrence. Emphasis is given to mammalian metabolism of PCBs and their hydroxyl, methylsulfonyl, and sulfated metabolites, especially those that persist in human blood. Potential intracellular targets and health risks are also discussed.
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Affiliation(s)
- FA Grimm
- Interdisciplinary Graduate Program in Human Toxicology, Department of Pharmaceutical Sciences & Experimental Therapeutics, University of Iowa
| | - D Hu
- Department of Civil and Environmental Engineering, University of Iowa
| | - I Kania-Korwel
- Department of Occupational & Environmental Health, University of Iowa
| | - HJ Lehmler
- Interdisciplinary Graduate Program in Human Toxicology, Department of Occupational & Environmental Health, University of Iowa
| | - G Ludewig
- Interdisciplinary Graduate Program in Human Toxicology, Department of Occupational & Environmental Health, University of Iowa
| | - KC Hornbuckle
- Interdisciplinary Graduate Program in Human Toxicology, Department of Civil and Environmental Engineering, University of Iowa
| | - MW Duffel
- Interdisciplinary Graduate Program in Human Toxicology, Department of Pharmaceutical Sciences & Experimental Therapeutics, University of Iowa
| | - A Bergman
- Swedish Toxicology Sciences Research Center (SWETOX), Forskargatan 20, SE-151 36 Södertälje, SWEDEN
| | - LW Robertson
- Interdisciplinary Graduate Program in Human Toxicology, Department of Occupational & Environmental Health, University of Iowa
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Marek R, Thorne PS, DeWall J, Hornbuckle KC. Variability in PCB and OH-PCB serum levels in children and their mothers in urban and rural U.S. communities. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:13459-67. [PMID: 25300024 PMCID: PMC4238695 DOI: 10.1021/es502490w] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 10/01/2014] [Accepted: 10/09/2014] [Indexed: 05/18/2023]
Abstract
Environmental exposures that affect accumulation of polychlorinated biphenyls (PCBs) in humans are complex and not fully understood. One challenge in linking environmental exposure to accumulation is determining variability of PCB concentrations in samples collected from the same person at different times. We hypothesized that PCBs in human blood serum are consistent from year to year in people who live in the same environment between sampling. We analyzed blood serum from children and their mothers from urban and rural U.S. communities (n = 200) for all 209 PCBs (median ∑PCBs = 45 ng/g lw) and 12 hydroxylated PCBs (median ∑OH-PCBs = 0.09 ng/g fw). A subset of these participants (n = 155) also had blood PCB and OH-PCB concentrations analyzed during the previous calendar year. Although many participants had similar levels of PCBs and OH-PCBs in their blood from one year to the next, some participants had surprisingly different levels. Year-to-year variability in ∑PCBs ranged from -87% to 567% and in ∑OH-PCBs ranged from -51 to 358% (5th-95th percentile). This is the first study to report variability of all PCBs and major metabolites in two generations of people and suggests short-term exposures to PCBs may be a significant component of what is measured in human serum.
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Affiliation(s)
- Rachel
F. Marek
- Department
of Civil & Environmental Engineering, The University of Iowa, Iowa City, Iowa 52242, United States
- IIHR-Hydroscience
and Engineering, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Peter S. Thorne
- Department
of Civil & Environmental Engineering, The University of Iowa, Iowa City, Iowa 52242, United States
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
- (P. S. T.) Phone: (319)
335-4216; fax: (319) 384-4138; e-mail:
| | - Jeanne DeWall
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Keri C. Hornbuckle
- Department
of Civil & Environmental Engineering, The University of Iowa, Iowa City, Iowa 52242, United States
- IIHR-Hydroscience
and Engineering, The University of Iowa, Iowa City, Iowa 52242, United States
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
- (K. C. H.) Phone: (319)
384-0789; fax: (319) 335-5660; e-mail:
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Dhakal K, Uwimana E, Adamcakova-Dodd A, Thorne PS, Lehmler HJ, Robertson LW. Disposition of phenolic and sulfated metabolites after inhalation exposure to 4-chlorobiphenyl (PCB3) in female rats. Chem Res Toxicol 2014; 27:1411-20. [PMID: 24988477 PMCID: PMC4137987 DOI: 10.1021/tx500150h] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PCBs, such as PCB3, are air contaminants in buildings and outdoors. Metabolites of PCB3 are potential endocrine disrupting chemicals and genotoxic agents. We studied the disposition of phenolic and sulfated metabolites after acute nose-only inhalation exposure to airborne PCB3 for 2 h in female rats. Inhalation exposure was carried out in three groups. In the first group, rats exposed to an estimated dose of 26 μg/rat were euthanized at 0, 1, 2, and 4 h after exposure. Highest concentrations of phenols and sulfates were observed at 0 h, and the values were 7 ± 1 and 560 ± 60 ng/mL in serum, 213 ± 120 and 842 ± 80 ng/g in liver, 31 ± 27 and 22 ± 7 ng/g in lung, and 27 ± 6 and 3 ± 0 ng/g in brain, respectively. First-order serum clearance half-lives of 0.5 h for phenols and 1 h for sulfates were estimated. In the second group, rats exposed to an estimated dose of 35 μg/rat were transferred to metabolism cages immediately after exposure for the collection of urine and feces over 24 h. Approximately 45 ± 5% of the dose was recovered from urine and consisted mostly of sulfates; the 18 ± 5% of the dose recovered from feces was exclusively phenols. Unchanged PCB3 was detected in both urine and feces but accounted for only 5 ± 3% of the dose. Peak excretion of metabolites in both urine and feces occurred within 18 h postexposure. In the third group, three bile-cannulated rats exposed to an estimated dose of 277 μg/rat were used for bile collection. Bile was collected for 4 h immediately after 2 h exposure. Biliary metabolites consisted mostly of sulfates, some glucuronides, and lower amounts of the free phenols. Control rats in each group were exposed to clean air. Clinical serum chemistry values, serum T4 level, and urinary 8-hydroxy-2'-deoxyguanosine were similar in treated and control rats. These data show that PCB3 is rapidly metabolized to phenols and conjugated to sulfates after inhalation and that both of these metabolites are distributed to liver, lungs, and brain. The sulfates elaborated into bile are either reabsorbed or hydrolyzed in the intestine and excreted in the feces as phenols.
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Affiliation(s)
- Kiran Dhakal
- Interdisciplinary Graduate Program in Human Toxicology and ‡Department of Occupational and Environmental Health, The University of Iowa , Iowa City, Iowa 52242-5000, United States
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Guo J, Capozzi SL, Kraeutler TM, Rodenburg LA. Global distribution and local impacts of inadvertently generated polychlorinated biphenyls in pigments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8573-80. [PMID: 24965012 DOI: 10.1021/es502291b] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The non-Aroclor congener 3,3'-dichlorobiphenyl (PCB 11) has been recently detected in air, water, sediment, and biota. It has been known since at least the 1970s that this congener is produced inadvertently during the production of certain organic pigments. PCB 11 was previously measured at parts-per-billion (ppb) levels in various printed materials obtained in the US. In this work, PCB 11 was detected in samples of common consumer goods including magazines, advertisements, maps, postcards, brochures, napkins, and garments from 26 countries in five continents at concentrations ranging from 0.27 to 86 ppb. Leaching tests confirmed that PCB 11 could be released from these materials into water. We also examined whether the known sources of PCB 11 were large enough to account for the levels of PCB 11 measured in the air, water, soil and sediment of the Delaware River Basin. A mass flow analysis suggests that the outflows and sequestration of PCB 11 in the basin total between 30 and 280 kg y(-1). If PCB 11 concentrations in pigments were at the maximum average (125 ppm) allowed under the Toxic Substances Control Act (TSCA), the estimated input of PCB 11 to the Delaware River Basin would be on the order of 42 kg y(-1). Despite the large uncertainty in these numbers, the results suggest that pigments may plausibly account for the levels of PCB 11 measured in the environment.
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Affiliation(s)
- Jia Guo
- Department of Environmental Science, Rutgers, The State University of New Jersey , New Brunswick, New Jersey 08901, United States
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