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Zhang H, Cui L, Si P, Zhou Y, Zhang Y, Zhang Y, Kong Q. Environmentally relevant concentrations of naphthenic acids initiate intestinal injury and gut microbiota dysbiosis in marine medaka (Oryzias melastigma). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2024; 273:106996. [PMID: 38852546 DOI: 10.1016/j.aquatox.2024.106996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 05/27/2024] [Accepted: 06/06/2024] [Indexed: 06/11/2024]
Abstract
Naphthenic acids (NAs) are important pollutants in marine crude oils and have obvious toxic effects on marine organisms. However, the effects of NAs on the intestine are largely unknown. Thus, we evaluated the effects of NAs exposure in the intestines of marine medaka. Fish were experimentally exposed to NAs (0.5 mg/L, 5 mg/L, and 10 mg/L) for 96 h and monitored for changes in intestinal histology, markers of oxidative stress, and intestinal microbiome responses. Significant mucosal damage, inflammation, and oxidative stress were observed in the intestines of marine medaka after exposure to NAs. In addition, significant changes in the gut microbiota were observed. Specifically, the relative abundance of Proteobacteria decreased, while that of Verrucomicrobiota increased in the high-concentration exposure group. In addition, nutrient synthesis and metabolism in the gut were affected. The results of this study contribute to a better understanding of the ecological risk of different concentrations of NAs to marine organisms. CAPSULE ABSTRACT: Changes in the gut microbial community of marine medaka (Oryzias melastigma) caused by naphthenic acids in the marine environment were investigated through the assessment of gut inflammatory factors and comprehensive analysis using 16S rDNA high-throughput sequencing. The results indicated the induction of intestinal inflammation and changes in the structural composition of the intestinal flora.
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Affiliation(s)
- Huanxin Zhang
- College of Geography and Environment, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong, PR China.
| | - Lihua Cui
- College of Geography and Environment, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong, PR China
| | - Panpan Si
- College of Geography and Environment, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong, PR China
| | - Yumiao Zhou
- College of the Environment and Ecology, Xiamen University, Xiamen 361005, Fujian, PR China
| | - Yu Zhang
- College of Geography and Environment, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong, PR China
| | - Youru Zhang
- College of Geography and Environment, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong, PR China
| | - Qiang Kong
- College of Geography and Environment, Shandong Normal University, 88 Wenhua Donglu, Jinan 250014, Shandong, PR China; Dongying Institute, Shandong Normal University, Dongying 257092, Shandong, PR China
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2
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Paul S, Hussain NAS, Lillico DME, Suara MA, Ganiyu SO, Gamal El-Din M, Stafford JL. Examining the immunotoxicity of oil sands process affected waters using a human macrophage cell line. Toxicology 2023; 500:153680. [PMID: 38006929 DOI: 10.1016/j.tox.2023.153680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/09/2023] [Accepted: 11/21/2023] [Indexed: 11/27/2023]
Abstract
Oil sands process affected water (OSPW) is produced during the surface mining of the oil sands bitumen deposits in Northern Alberta. OSPW contains variable quantities of organic and inorganic components causing toxic effects on living organisms. Advanced Oxidation Processes (AOPs) are widely used to degrade toxic organic components from OSPW including naphthenic acids (NAs). However, there is no established biological procedure to assess the effectiveness of the remediation processes. Our previous study showed that human macrophage cells (THP-1) can be used as a bioindicator system to evaluate the effectiveness of OSPW treatments through examining the proinflammatory gene transcription levels. In the present study, we investigated the immunotoxicological changes in THP-1 cells following exposure to untreated and AOP-treated OSPW. Specifically, using proinflammatory cytokine protein secretion assays we showed that AOP treatment significantly abrogates the ability of OSPW to induce the secretion of IL-1β, IL-6, IL-8, TNF-α, IL-1Ra and MCP-1. By measuring transcriptional activity as well as surface protein expression levels, we also showed that two select immune cell surface markers, CD40 and CD54, were significantly elevated following OSPW exposure. However, AOP treatments abolished the immunostimulatory properties of OSPW to enhance the surface expression of these immune proteins. Finally, a transcriptome-based approach was used to examine the proinflammatory effects of OSPW as well as the abrogation of immunotoxicity following AOP treatments. Overall, this research shows how a human macrophage cell-based biomonitoring system serves as an effective in vitro tool to study the immunotoxicity of OSPW samples before and after targeted remediation strategies.
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Affiliation(s)
- Sunanda Paul
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Nora A S Hussain
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Dustin M E Lillico
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Monsuru A Suara
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Soliu O Ganiyu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - James L Stafford
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.
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Zhang H, Si P, Kong Q, Ma J. Transcriptome reveals the toxicity and genetic response of zebrafish to naphthenic acids and benzo[a]pyrene at ambient concentrations. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 253:114700. [PMID: 36863161 DOI: 10.1016/j.ecoenv.2023.114700] [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: 10/16/2022] [Revised: 02/14/2023] [Accepted: 02/26/2023] [Indexed: 06/18/2023]
Abstract
Naphthenic acids (NAs) are typical contaminants in heavily crude oil. Benzo[a]pyrene (B[a]P) is also a component of crude oil, but their combined effects have not been systematically explored. In this study, zebrafish (Danio rerio) were used as the test organisms, and behavioral indicators and enzyme activities were used as toxicity indicators. Combined with the effects of environmental concentrations, the toxic effects of low concentrations of commercially available NAs (0.5 mg/LNA) and benzo[a]pyrene (0.8 μg/LBaP) at single and compound exposures (0.5 mg/LNA and 0.8 μg/LBaP) were assayed in zebrafish, and transcriptome sequencing technology was used to explore the molecular mechanism of the two compounds affecting zebrafish from the molecular biology level. Sensitive molecular markers that could indicate the presence of contaminants were screened. The results showed that (1) zebrafish in the NA and BaP exposure groups exhibited increased locomotor behavior, and the mixed exposure group exhibited inhibition of locomotor behavior. Oxidative stress biomarkers showed increased activity under single exposure and decreased activity under the mixed exposure. (2) NA stress led to changes in the activity of transporters and the intensity of energy metabolism; BaP directly stimulates the pathway of actin production. When the two compounds are combined, the excitability of neurons in the central nervous system is decreased, and the actin-related genes are down-regulated. (3) After BaP and Mix treatments, genes were enriched in the cytokine-receptor interaction and actin signal pathway, while NA increased the toxic effect on the mixed treatment group. In general, the interaction between NA and BaP has a synergistic effect on the transcription of zebrafish nerve and motor behavior-related genes, resulting in increased toxicity under combined exposure. The changes in expression of various zebrafish genes are manifested in the changes in the normal movement behavior of zebrafish and the intensification of oxidative stress in the apparent behavior and physiological indicators. CAPSULE ABSTRACT: We investigated the toxicity and genetic alterations caused by NA, B[a]P, and their mixtures in zebrafish in an aquatic environment using transcriptome sequencing technology and comprehensive behavioral analysis. These changes involved energy metabolism, the generation of muscle cells, and the nervous system.
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Affiliation(s)
- Huanxin Zhang
- College of Geography and Environment, Shandong Normal University, Jinan 250000, China.
| | - Panpan Si
- College of Geography and Environment, Shandong Normal University, Jinan 250000, China
| | - Qiang Kong
- College of Geography and Environment, Shandong Normal University, Jinan 250000, China
| | - Jinyue Ma
- College of Geography and Environment, Shandong Normal University, Jinan 250000, China
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Robinson CE, Elvidge CK, Frank RA, Headley JV, Hewitt LM, Little AG, Robinson SA, Trudeau VL, Vander Meulen IJ, Orihel DM. Naphthenic acid fraction compounds reduce the reproductive success of wood frogs (Rana sylvatica) by affecting offspring viability. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 316:120455. [PMID: 36270565 DOI: 10.1016/j.envpol.2022.120455] [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: 08/05/2022] [Revised: 10/07/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
Understanding the toxicity of organic compounds in oil sands process-affected water (OSPW) is necessary to inform the development of environmental guidelines related to wastewater management in Canada's oil sands region. In the present study, we investigated the effects of naphthenic acid fraction compounds (NAFCs), one of the most toxic components of OSPW, on mating behaviour, fertility, and offspring viability in the wood frog (Rana sylvatica). Wild adult wood frogs were exposed separately from the opposite sex to 0, 5, or 10 mg/L of OSPW-derived NAFCs for 24 h and then combined in outdoor lake water mesocosms containing the same NAFC concentrations (n = 2 males and 1 female per mesocosm, n = 3 mesocosms per treatment). Mating events were recorded for 48 h and egg masses were measured to determine adult fertility. NAFC exposure had no significant effect on mating behaviour (probability of amplexus and oviposition, amplexus and oviposition latency, total duration of amplexus and number of amplectic events) or fertility (fertilization success and clutch size). Tadpoles (50 individuals per mesocosm at hatching, and 15 individuals per mesocosm from 42 d post-hatch) were reared in the same mesocosms under chronic NAFC exposure until metamorphic climax (61-85 d after hatching). Offspring exposed to 10 mg/L NAFCs during development were less likely to survive and complete metamorphosis, grew at a reduced rate, and displayed more frequent morphological abnormalities. These abnormalities included limb anomalies at metamorphosis, described for the first time after NAFC exposure. The results of this study suggest that NAFCs reduce wood frog reproductive success through declines in offspring viability and therefore raise the concern that exposure to NAFCs during reproduction and development may affect the recruitment of native amphibian populations in the oil sands region.
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Affiliation(s)
- C E Robinson
- Department of Biology, Queen's University; Kingston, Ontario, K7L 3N6, Canada
| | - C K Elvidge
- Department of Biology, Queen's University; Kingston, Ontario, K7L 3N6, Canada
| | - R A Frank
- Water Science and Technology Directorate, Environment and Climate Change Canada, Burlington, Ontario, L7S 1A1, Canada
| | - J V Headley
- Watershed Hydrology and Ecology Research Division, Environment and Climate Change Canada, Saskatoon, Saskatchewan, S7N 3H5, Canada
| | - L M Hewitt
- Water Science and Technology Directorate, Environment and Climate Change Canada, Burlington, Ontario, L7S 1A1, Canada
| | - A G Little
- Department of Biology, Queen's University; Kingston, Ontario, K7L 3N6, Canada
| | - S A Robinson
- Ecotoxicoloy and Wildlife Health Division, Environment and Climate Change Canada, Ottawa, K1A 0H3, Ontario, Canada
| | - V L Trudeau
- Department of Biology, University of Ottawa; Ottawa, Ontario, K1N 6N5, Canada
| | - I J Vander Meulen
- Watershed Hydrology and Ecology Research Division, Environment and Climate Change Canada, Saskatoon, Saskatchewan, S7N 3H5, Canada; Department of Civil, Geological and Environmental Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5A9, Canada
| | - D M Orihel
- Department of Biology, Queen's University; Kingston, Ontario, K7L 3N6, Canada; School of Environmental Studies, Queen's University; Kingston, Ontario, K7L 3N6, Canada.
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Ji X, Li N, Ma M, Li X, Zhu K, Rao K, Wang Z, Wang J, Fang Y. Comparison of the mechanisms of estrogen disrupting effects between triphenyl phosphate (TPhP) and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 229:113069. [PMID: 34890987 DOI: 10.1016/j.ecoenv.2021.113069] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 11/30/2021] [Accepted: 12/05/2021] [Indexed: 06/13/2023]
Abstract
As the typical aryl-organophosphate flame retardants (OPFRs), triphenyl phosphate (TPhP) and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) were reported to be estrogen disruptors. However, estrogen receptor α (ERα) binding experiments could not explain their biological effects. In this study, their action on ERα, G protein-coupled estrogen receptor (GPER) and the synthesis of 17β-estradiol (E2) were investigated using in vitro assays and molecular docking. The results showed that TPhP acted as an ERα agonist and recruited steroid receptor co-activator 1 (SRC1) and 3 (SRC3), which was found for the first time. Unlike TPhP, TDCIPP acted as an ERα antagonist. However, both TPhP and TDCIPP activated the estrogen pathway by GPER in SKBR3 cells which were lack of ERα. Although molecular docking results revealed that both TPhP and TDCIPP could dock into ERα and GPER, their substituent groups and combination mode might affect the receptor activation. In addition, by using estrogen biosynthesis assay in H295R cells, both of TPhP and TDCIPP were found to promote E2 synthesis and E2/T ratio involving their different alteration on levels of progesterone, testosterone and estrone, and expression of various key genes. Our data proposed estrogen-disrupting mechanism frameworks of TPhP and TDCIPP. Moreover, our results will contribute to future construction of adverse outcome pathway (AOP) framework of endocrine disruptors.
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Affiliation(s)
- Xiaoya Ji
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Public Health, Qingdao University, Qingdao 266000, China
| | - Na Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Mei Ma
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Xinyan Li
- Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Kongrui Zhu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaifeng Rao
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zijian Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfeng Wang
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Yanjun Fang
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
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6
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Bhuiyan MNH, Kang H, Choi J, Lim S, Kho Y, Choi K. Effects of 3,4-dichloroaniline (3,4-DCA) and 4,4'-methylenedianiline (4,4'-MDA) on sex hormone regulation and reproduction of adult zebrafish (Danio rerio). CHEMOSPHERE 2021; 269:128768. [PMID: 33153842 DOI: 10.1016/j.chemosphere.2020.128768] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 10/16/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
3,4-dichloroaniline (3,4-DCA) and 4,4'-methylenedianiline (4,4'-MDA) have been widely used in manufacture of many industrial and consumer products, and hence often detected in aquatic environment. Reproductive toxicity of aniline and its derivatives in aquatic organisms has been suggested, however, knowledge on the endocrine disruption potentials and toxicological consequences of both anilines are not well understood, especially in fish. In this study, we aimed to understand the effects of 3,4-DCA and 4,4'-MDA on sex hormone regulation and reproduction of adult zebrafish (Danio rerio). Following 21 d exposure, significant decreases of the reproduction were observed at 0.38 mg/L 3,4-DCA, and 4.6 mg/L 4,4'-MDA. Moreover, plasma concentrations of testosterone (T) and 17β-estradiol (E2) level were significantly decreased in both male and female fish following the exposure. The sex hormone changes could be explained by the regulatory changes of the genes along the hypothalamic-pituitary-gonadal (HPG) axis, including significant down-regulation of steroidogenic acute regulatory protein (star) and cytochrome P450 family 19 subfamily A (cyp19a) genes in the gonad. Moreover, inhibition of gonadotropin hormone signaling and prostaglandin-endoperoxide synthase 2 (ptgs2) gene expression were observed, suggesting potential disruption of oocyte maturation and ovulation by the exposure. Our observations indicate that 3,4-DCA and 4,4'-MDA can impair reproduction of zebrafish potentially through disruption of steroid hormone synthesis and ovulation.
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Affiliation(s)
- Md Nurul Huda Bhuiyan
- Graduate School of Public Health, Seoul National University, Seoul, 08826, Republic of Korea; Bangladesh Council of Scientific and Industrial Research, Dhaka, 1205, Bangladesh
| | - Habyeong Kang
- Graduate School of Public Health, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jiwon Choi
- Graduate School of Public Health, Seoul National University, Seoul, 08826, Republic of Korea
| | - Soyoung Lim
- Graduate School of Public Health, Seoul National University, Seoul, 08826, Republic of Korea
| | - Younglim Kho
- Department of Health, Environment and Safety, Eulji University, Seongnam, 34824, Republic of Korea
| | - Kyungho Choi
- Graduate School of Public Health, Seoul National University, Seoul, 08826, Republic of Korea.
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7
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Lin F, Wang Z, Zhang Z, Xiang L, Yuan D, Yan B, Wang Z, Chen G. Comparative Investigation on Chlorobenzene Oxidation by Oxygen and Ozone over a MnO x/Al 2O 3 Catalyst in the Presence of SO 2. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:3341-3351. [PMID: 33605716 DOI: 10.1021/acs.est.0c07862] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Catalytic oxidation of volatile organic compounds (VOCs) usually encounters complicated components in flue gas causing severe deactivation that restrict its application in specific conditions. The Cl substitution in chlorobenzene further increases poisoning risks. Ozone assistance has unique superiority that can overcome these bottleneck problems. Herein, this study performs a comparative investigation of CB oxidation by oxygen and ozone over a simple Mn/Al2O3 catalyst. CB conversion suffered from slight deactivation in oxygen atmosphere (from 90 to 70%) and more severe deactivation in the presence of SO2 (from 90 to 45%) at 480 °C. Introduction of ozone successfully attained high CB conversion at low temperature (120 °C) with excellent stability and less byproducts. Especially, CB oxidation by ozone maintained its original conversion in the presence of SO2. The deactivation process was simulated by synthesizing several sulfated catalysts. Direct sulfation on Mn/Al2O3 attained more severe deactivation in CB conversion and CO2 formation than sulfation on the Al2O3 support. Ozone with a strong oxidation property promoted the CB oxidation cycle, facilitated desorption of carbonaceous intermediates, and protected MnOx species from severe erosion, thus exhibiting high and stable performance in CB oxidation.
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Affiliation(s)
- Fawei Lin
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, P. R. China
| | - Zhi Wang
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, P. R. China
| | - Zhiman Zhang
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, P. R. China
| | - Li Xiang
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, P. R. China
| | - Dingkun Yuan
- The Institute for Energy Engineering, China Jiliang University, Hangzhou 310000, P. R. China
| | - Beibei Yan
- School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, P. R. China
| | - Zhihua Wang
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, P. R. China
| | - Guanyi Chen
- School of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134, P. R. China
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8
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Raez-Villanueva S, Perono GA, Jamshed L, Thomas PJ, Holloway AC. Effects of dibenzothiophene, a sulfur-containing heterocyclic aromatic hydrocarbon, and its alkylated congener, 2,4,7-trimethyldibenzothiophene, on placental trophoblast cell function. J Appl Toxicol 2020; 41:1367-1379. [PMID: 33314207 DOI: 10.1002/jat.4128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/19/2020] [Accepted: 12/04/2020] [Indexed: 12/31/2022]
Abstract
Worldwide demand for petroleum products has resulted in increased oil and gas activities in many countries. Conventional and unconventional oil and gas extraction, production, and transport lead to increased levels of petroleum-derived polycyclic aromatic hydrocarbons (PAHs) in the environment. PAH exposure has profound effects on reproduction by affecting pathways involved in placental trophoblast cell function and impairing normal placental development and function-key contributors to reproductive success. However, other components found in petroleum and wastewaters from oil and gas extraction, including the sulfur-containing heterocyclic aromatic compounds such as dibenzothiophene (DBT) and its alkylated derivatives, may also impact reproductive success. The goal of this study was to examine the effect of exposure to DBT, a compound commonly detected in the environment, and one of its alkylated analogues, 2,4,7-trimethyldibenzothiophene (2,4,7-DBT), on steroidogenic and angiogenic pathways critical for mammalian development in placental trophoblast cells (HTR-8/SVneo cells). 2,4,7-DBT but not DBT increased estradiol output in association with increased tube-like formation (surrogate for angiogenesis). These changes in angiogenesis did not appear to be related to altered expression of the key placental angiogenic gene targets (ANGPTL4, VEGFA, and PGF). Neither compound showed a concentration related effect on progesterone synthesis or its receptor expression. Our results suggest that 2,4,7-DBT can disrupt key pathways important for placental trophoblast function and highlight the importance of determining the impact of exposure to both parent and alkylated compounds. Further, these data suggest that exposure to sulfur-containing heterocyclic aromatic compounds may lead to placental dysfunction and impact reproductive success at environmentally relevant levels.
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Affiliation(s)
| | - Genevieve A Perono
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada
| | - Laiba Jamshed
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada
| | - Philippe J Thomas
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario, Canada
| | - Alison C Holloway
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada
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9
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Duan C, Fang Y, Sun J, Li Z, Wang Q, Bai J, Peng H, Liang J, Gao Z. Effects of fast food packaging plasticizers and their metabolites on steroid hormone synthesis in H295R cells. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 726:138500. [PMID: 32334352 DOI: 10.1016/j.scitotenv.2020.138500] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/30/2020] [Accepted: 04/04/2020] [Indexed: 06/11/2023]
Abstract
The health risks of exposure to plasticizers have received widespread attention, however, little is known about the effects of fast food packaging plasticizers on steroid hormone synthesis. In the present study, the types and migration of plasticizers in some commonly used fast-food packaging materials were detected by GC-MS, and the interference effects of these plasticizers and their metabolites on steroid hormone synthesis in the human body were evaluated by the H295R steroidogenesis assay. The GC-MS results showed that the main plasticizer compounds that migrated from fast food packaging into food were di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and bis(2-ethylhexyl) adipate (DEHA). Exposure to these chemicals (100-1000 μM) can significantly reduce the viability of H295R cells in a dose-response manner, and these plasticizers and their metabolites that migrated into oily foods at high temperatures (0.25-25 μM) could significantly increase the E2 level and reduce the T level in H295R cells. According to the qRT-PCR data, 0.25 to 25 μM mono(2-ethylhexyl) phthalate (MEHP) significantly upregulated the expression levels of 17β-HSD1 and CYP19A1, and downregulated those of CYP17A1, CYP11A1 and StAR. The Western blot results were consistent with those of qRT-PCR. In summary, these results indicated that even exposure to low concentrations (≤1 mg/l or 2.5 μM) of these chemicals and their metabolites can cause significant endocrine-disrupting effects.
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Affiliation(s)
- Chenhui Duan
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Tianjin 30045, China; Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Yanjun Fang
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Jingran Sun
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Zhenxin Li
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Qiangqiang Wang
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Jialei Bai
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Hui Peng
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Jun Liang
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Tianjin 30045, China.
| | - Zhixian Gao
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China.
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10
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Raez-Villanueva S, Jamshed L, Ratnayake G, Cheng L, Thomas PJ, Holloway AC. Adverse effects of naphthenic acids on reproductive health: A focus on placental trophoblast cells. Reprod Toxicol 2019; 90:126-133. [DOI: 10.1016/j.reprotox.2019.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 09/02/2019] [Accepted: 09/10/2019] [Indexed: 01/09/2023]
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Philibert DA, Lyons DD, Qin R, Huang R, El-Din MG, Tierney KB. Persistent and transgenerational effects of raw and ozonated oil sands process-affected water exposure on a model vertebrate, the zebrafish. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 693:133611. [PMID: 31634996 DOI: 10.1016/j.scitotenv.2019.133611] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 06/10/2023]
Abstract
Exposure to oil sands process-affected water (OSPW), a by-product of Canadian oil sands mining operations, can cause both acute and chronic adverse effects in aquatic life. Ozonation effectively degrades naphthenic acids in OSPW, mitigating some of the toxicological effects of exposure. In this study we examined the effect of developmental exposure to raw and ozonated OSPW had on the breeding success, prey capture, and alarm cue response in fish months/years after exposure and the transgenerational effect exposure had on gene expression, global DNA methylation, and larval basal activity. Exposure to raw and ozonated OSPW had no effect on breeding success, and global DNA methylation. Exposure altered the expression of vtg and nkx2.5 in the unexposed F1 generation. Exposure to both raw and ozonated OSPW had a transgenerational impact on larval activity levels, anxiety behaviors, and maximum swim speed compared to the control population. Prey capture success was unaffected, however, the variability in the behavioral responses to the introduction of prey was decreased. Fish developmentally exposed to either treatment were less active before exposure and did not have an anxiety response to the alarm cue hypoxanthine-3-n-oxide. Though ozonation was able to mitigate some of the effects of OSPW exposure, further studies are needed to understand the transgenerational effects and the implications of exposure on complex fish behaviors.
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Affiliation(s)
- Danielle A Philibert
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
| | - Danielle D Lyons
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Rui Qin
- Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Rongfu Huang
- Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Mohamed Gamal El-Din
- Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Ketih B Tierney
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada; School of Public Health, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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12
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Huda Bhuiyan MN, Kang H, Kim JH, Kim S, Kho Y, Choi K. Endocrine disruption by several aniline derivatives and related mechanisms in a human adrenal H295R cell line and adult male zebrafish. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 180:326-332. [PMID: 31100596 DOI: 10.1016/j.ecoenv.2019.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/27/2019] [Accepted: 05/01/2019] [Indexed: 06/09/2023]
Abstract
Aniline and aniline derivatives have been widely used in the production of pesticides, pharmaceuticals, cosmetic, dyes, rubber, and adhesives products. These chemicals can easily be released into the environment through industrial and municipal discharges or as degradation byproducts. Several studies have suggested that aniline and some of its derivatives could cause reproductive toxicity in aquatic organisms. However, knowledge on the endocrine disruption potentials of these chemicals is limited only to aniline and associated mechanisms are rarely investigated. The objective of this study was to investigate the potential of major aniline derivatives, i.e., 3,4-dichloroaniline (3,4-DCA), 1-naphthylamine (1-NPA), and 4,4'-methylenedianiline (4,4'-MDA), to disrupt sex steroid production and other biological processes. For this purpose, the human adrenal H295R cell line and adult male zebrafish (Danio rerio) were used. In the H295R cell line, all tested aniline derivatives decreased testosterone (T) levels. Regulatory changes of several steroidogenic genes, i.e., down-regulation of StAR or CYP17 genes, and up-regulation of CYP19A, observed in the H295R cells could explain the sex hormone disruption. In male zebrafish, generally similar directions of changes, i.e., decreases in T levels and increased E2/T ratios, were observed. Again, down-regulation of key steroidogenic genes such as cyp17 or 3β-hsd, but slight up-regulation of cyp19a gene observed in the fish could explain the sex hormone changes. The results of our study demonstrate that all tested aniline derivatives could influence steroidogenesis and disrupt sex hormone balance toward reduced androgenicity. Consequences of anti-androgenicity following long-term exposure warrant further investigation.
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Affiliation(s)
- Md Nurul Huda Bhuiyan
- Graduate School of Public Health, Seoul National University, Seoul 08826, Republic of Korea
| | - Habyeong Kang
- Graduate School of Public Health, Seoul National University, Seoul 08826, Republic of Korea
| | - Ji Hyun Kim
- Graduate School of Public Health, Seoul National University, Seoul 08826, Republic of Korea
| | - Sungmin Kim
- Department of Health, Environment and Safety, Eulji University, Seongnam 34824, Republic of Korea
| | - Younglim Kho
- Department of Health, Environment and Safety, Eulji University, Seongnam 34824, Republic of Korea
| | - Kyungho Choi
- Graduate School of Public Health, Seoul National University, Seoul 08826, Republic of Korea.
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13
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Li C, Fu L, Lillico DME, Belosevic M, Stafford JL, Gamal El-Din M. Exposure to Organic Fraction Extracted from Oil Sands Process-Affected Water Has Negligible Impact on Pregnancy and Lactation of Mice. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:7083-7094. [PMID: 31117544 DOI: 10.1021/acs.est.9b01965] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Dissolved organic compounds are major contaminants in oil sands process-affected water (OSPW), of which naphthenic acids (NAs) are one of the main persistent toxicants. In the present study, we explore the toxic effects of the organic fraction extracted from OSPW (OSPW-OF) in mice during pregnancy and lactation. Here, we report that acute oral exposure of female Balb/c mice during gestation, and subchronic exposure throughout gestation and lactation to OSPW-OF (containing naturally occurring levels of NAs found in tailings ponds), had negligible effects on their reproductive performance. Specifically, mating behavior, pregnancy success, embryonic implantation, gestation period, litter size, and offspring viability were not affected by OSPW-OF containing up to 55 mg/L NAs. OSPW-OF exposure also did not affect plasma concentrations of pregnancy-associated hormones or pro- and anti-inflammatory cytokines, and it had minimal effects on liver stress gene expression. This study presents the first comprehensive in vivo analysis of mammalian toxicity associated with OSPW-OF exposure. Overall, our results suggest that the risk of acute and subchronic toxicity to mice exposed to OSPW-OF at environmentally relevant concentrations of NAs in contaminated drinking water is likely negligible.
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Affiliation(s)
- Chao Li
- Department of Civil and Environmental Engineering , University of Alberta , Edmonton , Alberta Canada T6G 1H9
| | - Li Fu
- Department of Civil and Environmental Engineering , University of Alberta , Edmonton , Alberta Canada T6G 1H9
- Department of Biological Sciences , University of Alberta , Edmonton , Alberta Canada T6G 2E9
| | - Dustin M E Lillico
- Department of Biological Sciences , University of Alberta , Edmonton , Alberta Canada T6G 2E9
| | - Miodrag Belosevic
- Department of Biological Sciences , University of Alberta , Edmonton , Alberta Canada T6G 2E9
| | - James L Stafford
- Department of Biological Sciences , University of Alberta , Edmonton , Alberta Canada T6G 2E9
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering , University of Alberta , Edmonton , Alberta Canada T6G 1H9
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14
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Lyons DD, Morrison C, Philibert DA, Gamal El-Din M, Tierney KB. Growth and recovery of zebrafish embryos after developmental exposure to raw and ozonated oil sands process-affected water. CHEMOSPHERE 2018; 206:405-413. [PMID: 29758497 DOI: 10.1016/j.chemosphere.2018.05.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/03/2018] [Accepted: 05/04/2018] [Indexed: 06/08/2023]
Abstract
Due to the increasing volume of oil sands process-affect water (OSPW) and its toxicity to aquatic organisms, it is important to fully understand its effects and study remediation processes that will enable its release to the environment. Ozone treatment is currently being considered as a tool to expedite remediation, as it is known to degrade toxic organic compounds present in OSPW. In this study, we aimed to measure the effects of OSPW exposure on the growth, development and recovery of zebrafish (Danio rerio) embryos. We also used ozone-treated OSPW to determine whether ozonation negated any effects of raw OSPW exposure. As biomarkers of exposure, we assessed the expression of genes involved in neurodevelopment (ngn1, neuroD), estrogenicity (vtg), oxidative stress (sod1), and biotransformation (cyp1a, cyp1b). Our study found that exposure to both raw and ozonated OSPW did not impair growth of zebrafish embryos, however, otoliths of exposed embryos were smaller than those of control embryos. The expression levels of both cyp1a and cyp1b were induced by raw OSPW exposure. However, after the exposure period, expression levels of these genes returned to control levels within two days of residence in clean water. We found no changes in the expression levels of ngn1, neuroD and vtg genes with exposure to treated or untreated OSPW. Overall, our study found that raw OSPW exposure did not have many negative effects on zebrafish embryos and embryos appeared to recover relatively quickly after exposure ended. Furthermore, ozone treatment decreased the induction of cyp1a and cyp1b.
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Affiliation(s)
- Danielle D Lyons
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
| | - Christie Morrison
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Danielle A Philibert
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Mohamed Gamal El-Din
- Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Keith B Tierney
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada; School of Public Health, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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15
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Wangmo C, Jarque S, Hilscherová K, Bláha L, Bittner M. In vitro assessment of sex steroids and related compounds in water and sediments - a critical review. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2018; 20:270-287. [PMID: 29251308 DOI: 10.1039/c7em00458c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Detection of endocrine disrupting compounds in water and sediment samples has gained much importance since the evidence of their effects was reported in aquatic ecosystems in the 1990s. The aim of this review is to highlight the advances made in the field of in vitro analysis for the detection of hormonally active compounds with estrogenic, androgenic and progestogenic effects in water and sediment samples. In vitro assays have been developed from yeast, mammalian and in a few cases from fish cells. These assays are based either on the hormone-mediated proliferation of sensitive cell lines or on the hormone-mediated expression of reporter genes. In vitro assays in combination with various sample enrichment methods have been used with limits of detection as low as 0.0027 ng L-1 in water, and 0.0026 ng g-1 in sediments for estrogenicity, 0.1 ng L-1 in water, and 0.5 ng g-1 in sediments for androgenicity, and 5 ng L-1 in water for progestogenicity expressed as equivalent concentrations of standard reference compounds of 17β-estradiol, dihydrotestosterone and progesterone, respectively. The experimental results and limits of quantification, however, are influenced by the methods of sample collection, preparation, and individual laboratory practices.
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Affiliation(s)
- Chimi Wangmo
- Masaryk University, Research Centre for Toxic Compounds in the Environment - RECETOX, Kamenice 5, 625 00, Brno, Czech Republic.
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16
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Yang X, Song W, Liu N, Sun Z, Liu R, Liu QS, Zhou Q, Jiang G. Synthetic Phenolic Antioxidants Cause Perturbation in Steroidogenesis in Vitro and in Vivo. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:850-858. [PMID: 29236469 DOI: 10.1021/acs.est.7b05057] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Synthetic phenolic antioxidants (SPAs) are closely correlated with human life due to their extensive usages, and increasing concerns have been raised on their biosafety. The previous controversial findings caused continuous debates on their potential endocrine disrupting effects. In the present study, four commonly used SPAs, including butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tert-butyl hydroquinone (TBHQ) and 2,2'-methylenebis(6-tert-butyl-4-methylphenol) (AO2246), were investigated for their estrogenic effects, and the results from in vitro screening assays showed SPAs themselves had negligible estrogen receptor binding affinities. Nevertheless, significant increase in E2 secretion was observed in H295R cells treated with SPAs, especially for BHA. The transcriptional levels of steroidogenic enzymes, including StAR, 3βHSD, CYP11B1, and CYP11B2 were up-regulated via the mediation of protein kinase A (PKA) signaling pathway. In vivo experiment confirmed that waterborne exposure to BHA disturbed E2 and testosterone (T) levels in zebrafish gonad, thus causing potential estrogenic effects through the regulation of hypothalamic-pituitary-gonadal-liver axis (HPGL-axis). Accordingly, this study has provided new insights for SPA-induced endocrine disrupting effects. Considering the allowable maximum level of individual BHA or in combination with TBHQ and BHT in foodstuffs (200 mg kg-1), the perturbation in steroidogenesis observed for relatively low concentrations of SPAs would need more public attention.
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Affiliation(s)
- Xiaoxi Yang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
| | - Wenting Song
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- Medical College, Henan Polytechnic University , Jiaozuo 454000, China
| | - Na Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- School of Life Science, Shanxi University , Taiyuan 030006, China
| | - Zhendong Sun
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
| | - Ruirui Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
| | - Qian S Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
| | - Qunfang Zhou
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
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17
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Petersen K, Hultman MT, Rowland SJ, Tollefsen KE. Toxicity of organic compounds from unresolved complex mixtures (UCMs) to primary fish hepatocytes. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2017; 190:150-161. [PMID: 28711771 DOI: 10.1016/j.aquatox.2017.06.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 06/06/2017] [Accepted: 06/12/2017] [Indexed: 06/07/2023]
Abstract
Many environmental matrices contaminated with organic pollutants derived from crude oil or degraded petroleum contain mixtures so complex that they are typically unresolved by conventional analytical techniques such as gas chromatography. The resulting chromatographic features have become known as 'humps' or unresolved complex mixtures (UCMs). These UCMs often dominate the organic contaminants of polluted environmental samples: for example, in oil sands produced water up to 150mgL-1 of 'naphthenic acids' appear as UCMs when examined by gas chromatography as the esters. In oil-contaminated mussels, aromatic hydrocarbon UCMs may comprise almost all of the total toxic hydrocarbons, with over 7000μgg-1 dry weight reported in some samples. Over the last 25 years, efforts to resolve and thus identify, or at least to produce average structures, for some UCM components, have proved fruitful. Numerous non-polar UCM hydrocarbons and more polar UCM acids have been identified, then synthesised or purchased from commercial suppliers. As UCMs have been proposed to represent a risk to aquatic organisms, the need for assessment of the ecotoxicological effects and characterisation of the mode of action (MoA) of these environmental pollutants has arisen. In the present study, several chemicals with structures typical of those found in some UCMs, were assessed for their potential to disrupt membrane integrity, inhibit metabolic activity, activate the aryl hydrocarbon receptor (AhR), and activate the estrogen receptor (ER) in primary rainbow trout hepatocytes (Oncorhynchus mykiss). These endpoints were determined in order to screen for common toxic modes of action (MoA) in this diverse group of chemicals. The results from the in vitro screening indicated that of the endpoints tested, the predominant toxic MoA was cytotoxicity. EC50 values for cytotoxicity were obtained for 16 compounds and ranged from 77μM-24mM, whereof aliphatic monocyclic acids, monoaromatic acids, polycyclic monoaromatic acids and alkylnaphthalenes were the most toxic. The observed cytotoxicity of the chemicals correlated well with the hydrophobicity (LogKOW) suggesting that the toxicity was predominantly due to a non-specific MoA. Interestingly, two compounds induced the ER-mediated production of vitellogenin (Vtg) and six compounds induced the AhR-mediated Ethoxyresorufin-O-deethylase (EROD) enzymatic activity to >20% of the positive control; by doing so suggesting that they may act as ER or AhR agonists in fish. The heterogeneous group of 'UCM compounds' tested exhibited multiple MoA that may potentially cause adverse effects in fish. Additional studies to determine if these compounds may cause adverse effects in vivo at environmentally relevant concentrations, are warranted to identify if such compounds are indeed of potential environmental concern.
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Affiliation(s)
- Karina Petersen
- Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo, Norway
| | - Maria T Hultman
- Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo, Norway; Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences (NMBU), Post box 5003, N-1432 Ås, Norway
| | - Steven J Rowland
- Petroleum & Environmental Geochemistry Group, Biogeochemistry Research Centre, University of Plymouth, Plymouth, PL4 8AA, Devon, UK
| | - Knut Erik Tollefsen
- Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo, Norway; Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences (NMBU), Post box 5003, N-1432 Ås, Norway.
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