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Fischer J, Talal GDA, Schnee LS, Otomo PV, Filser J. Clay Types Modulate the Toxicity of Low Concentrated Copper Oxide Nanoparticles Toward Springtails in Artificial Test Soils. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2022; 41:2454-2465. [PMID: 35856869 DOI: 10.1002/etc.5440] [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: 04/08/2022] [Revised: 05/24/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Copper oxide nanoparticles (CuO-NPs) can be applied as an efficient alternative to conventional Cu in agriculture. Negative effects of CuO-NPs on soil organisms were found, but only in clay-rich loamy soils. It is hypothesized that clay-NP interactions are the origin of the observed toxic effects. In the present study, artificial Organisation for Economic Co-operation and Development soils containing 30% of kaolin or montmorillonite as clay type were spiked with 1-32 mg Cu/kg of uncoated CuO-NPs or CuCl2 . We performed 28-day reproduction tests with springtails of the species Folsomia candida and recorded the survival, reproduction, dry weight, and Cu content of adults. In a second experiment, molting frequency and the Cu content of exuviae, as well as the biochemical endpoints metallothionein and catalase (CAT) in springtails, were investigated. In the reproduction assay, negative effects on all endpoints were observed, but only in soils containing montmorillonite and mostly for CuO-NPs. For the biochemical endpoints and Cu content of exuviae, effects were clearly distinct between Cu forms in montmorillonite soil, but a significant reduction compared to the control was only found for CAT activity. Therefore, the reduced CAT activity in CuO-NP-montmorillonite soil might be responsible for the observed toxicity, potentially resulting from reactive oxygen species formation overloading the antioxidant system. This process seems to be highly concentration-dependent, because all endpoints investigated in reproduction and biochemical assays of CuO-NP-montmorillonite treatments showed a nonlinear dose-response relationship and were constantly reduced by approximately 40% at a field-realistic concentration of 3 mg/kg, but not at 32 mg/kg. The results underline that clay-CuO-NP interactions are crucial for their toxic behavior, especially at low, field-realistic concentrations, which should be considered for risk assessment of CuO-NPs. Environ Toxicol Chem 2022;41:2454-2465. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Affiliation(s)
- Jonas Fischer
- Department of General and Theoretical Ecology, University of Bremen, UFT, Bremen, Germany
| | - Ghanem D A Talal
- Department of General and Theoretical Ecology, University of Bremen, UFT, Bremen, Germany
| | - Laura S Schnee
- Department of General and Theoretical Ecology, University of Bremen, UFT, Bremen, Germany
- Institute of Mineralogy, Soil Mineralogy, Gottfried Wilhelm Leibniz University of Hannover, Hannover, Germany
| | - Patricks V Otomo
- Department of Zoology and Entomology, University of The Free State, Phuthaditjhaba, Republic of South Africa
| | - Juliane Filser
- Department of General and Theoretical Ecology, University of Bremen, UFT, Bremen, Germany
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Thit A, Sandgaard MH, Sturve J, Mouneyrac C, Baun A, Selck H. Influence of Aging on Bioaccumulation and Toxicity of Copper Oxide Nanoparticles and Dissolved Copper in the Sediment-Dwelling Oligochaete Tubifex tubifex: A Long-Term Study Using a Stable Copper Isotope. FRONTIERS IN TOXICOLOGY 2022; 3:737158. [PMID: 35295142 PMCID: PMC8915916 DOI: 10.3389/ftox.2021.737158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/16/2021] [Indexed: 11/16/2022] Open
Abstract
For engineered metal nanoparticles (NPs), such as copper oxide (CuO) NPs, the sediment is recognized as a major compartment for NP accumulation. Sediment-dwelling organisms, such as the worm Tubifex tubifex, will be at particular risk of metal and metal NP exposure. However, a range of complex transformation processes in the sediment affects NP bioavailability and toxicity as the contamination ages. The objective of this study was to examine bioaccumulation and adverse effects of CuO NPs in T. tubifex compared to dissolved Cu (administered as CuCl2) and the influence of aging of spiked sediment. This was done in a 28-day exposure experiment with T. tubifex incubated in clean sediment or freshly spiked sediment with different concentrations of dissolved Cu (up to 230 μg g−1 dw) or CuO NPs (up to 40 μg g−1 dw). The experiment was repeated with the same sediments after it had been aged for 2 years. To obtain a distinct isotopic signature compared to background Cu, both Cu forms were based on the stable isotope 65Cu (>99%). The 28-day exposure to sediment-associated dissolved 65Cu and 65CuO NPs resulted in a clear concentration-dependent increase in the T. tubifex65Cu body burden. However, despite the elevated 65Cu body burdens in exposed worms, limited adverse effects were observed in either of the two experiments (e.g., above 80% survival in all treatments, low or no effects on the growth rate, feeding rate, and reproduction). Organisms exposed to aged sediments had lower body burdens of 65Cu than those exposed to freshly spiked sediments and we suggest that aging decreases the bioavailability of both 65Cu forms. In this study, the use of a stable isotope made it possible to use environmentally realistic Cu concentrations and, at the same time, differentiate between newly accumulated 65Cu and background Cu in experimental samples despite the high background Cu concentrations in sediment and T. tubifex tissue. Realistic exposure concentrations and aging of NPs should preferably be included in future studies to increase environmental realism to accurately predict the environmental risk of metal NPs.
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Affiliation(s)
- Amalie Thit
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | | | - Joachim Sturve
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Catherine Mouneyrac
- Faculty of Sciences, BIOSSE, Université Catholique de L'Ouest, Angers, France
| | - Anders Baun
- Department of Environmental Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Henriette Selck
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
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Thit A, Selck H. Biodynamics and adverse effects of CuO nanoparticles and CuCl 2 in the oligochaete T. tubifex: Cu form influence biodynamics in water, but not sediment. Nanotoxicology 2021; 15:673-689. [PMID: 34137642 DOI: 10.1080/17435390.2021.1913657] [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] [Indexed: 10/21/2022]
Abstract
The use of copper oxide (CuO) NPs results in the release of these particles into the aquatic environment. Here, the particles settle out and accumulate in the sediment. However, little is known about the biodynamics of sediment-associated NPs in benthic organisms. We compared the toxicity and biodynamics of CuO NPs (7 nm) and dissolved Cu (CuCl2) in the sediment-dwelling oligochaete, Tubifex tubifex, to gain insights into the relative importance of metal form (CuCl2 vs CuO NPs) and exposure route (water vs sediment). Isotopically enriched 65Cu was used as a tracer to distinguish background from newly accumulated 65Cu in worms. For each exposure route, we conducted three experiments: one uptake, one elimination, and one longer-term net accumulation experiment to parameterize uptake and elimination of 65CuCl2 and 65CuO NPs in T. tubifex. 65Cu accumulation was detected for both 65CuCl2 and 65CuO NPs regardless of whether T. tubifex were exposed in sediment- or water-only setups. Water exposures to 65CuCl2 resulted in tail trauma whereas limited effects were seen for sediment exposures or exposures to 65CuO NPs via either exposure route. Uptake rate constants and accumulation of 65Cu in T. tubifex were higher following 65CuCl2 exposure than 65CuO NPs, in water, but not in sediment. Thus, the relative importance of exposure route and Cu form for uptake dynamics is not straightforward suggesting that findings on bioaccumulation and toxicity in water exposures cannot be directly extrapolated to sediment.
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Affiliation(s)
- Amalie Thit
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | - Henriette Selck
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
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Guo Z, Ye H, Xiao J, Hogstrand C, Zhang L. Biokinetic Modeling of Cd Bioaccumulation from Water, Diet and Sediment in a Marine Benthic Goby: A Triple Stable Isotope Tracing Technique. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:8429-8437. [PMID: 29983045 DOI: 10.1021/acs.est.8b00027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Aquatic animals are often simultaneously exposed to metals through multiple routes in the natural environment. This study explored a triple stable isotope tracing method to quantify simultaneous cadmium (Cd) uptake biokinetics by yellow stripe goby from water (traced by 110Cd), sediment (traced by 111Cd), and diet (traced by 113Cd) when the fish were exposed to Cd for 24 h. The simultaneous uptake of Cd from multiple routes during 4 weeks was then predicted by the modified biokinetic model. The results demonstrated that the uptake rate constant of waterborne 110Cd, sediment-associated 111Cd, and dietary 113Cd was 3.1 L kg-1 d-1, 2.2 × 10-4 g g-1 d-1, and 3.3 × 10-3 g g-1 d-1 in the fish. Sedimentary Cd was less bioavailable than the waterborne and dietary Cd; however, sediment could become the predominant Cd source of the total Cd bioaccumulation when the partition coefficient of Cd between sediment and seawater ( Kd) is larger than 6 × 104 L kg-1. The simultaneous uptake of Cd from the three routes could be successfully predicted by the modified model. The model revealed that the Cd bioaccumulation generally increased with the increase of ambient Cd concentration in all the three routes. Overall, our findings demonstrated that the multiple stable isotopes tracing method and the modified biokinetic model have a wide generality and applicability for predicting Cd bioaccumulation under multiple routes of metal exposure scenario and may have application to other metals.
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Affiliation(s)
- Zhiqiang Guo
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology , Chinese Academy of Sciences , Guangzhou 510301 , China
- State Key Laboratory of Marine Resource Utilization in South China Sea, College of Marine Science , Hainan University , Haikou 570228 , China
| | - Hengzhen Ye
- State Key Laboratory of Marine Resource Utilization in South China Sea, College of Marine Science , Hainan University , Haikou 570228 , China
| | - Juan Xiao
- College of Food Science and Technology , Hainan University , Haikou 570228 , China
| | - Christer Hogstrand
- Metals Metabolism Group, School of Life Course Sciences , King's College London , 150 Stamford Street , London SE1 9NH , U.K
| | - Li Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology , Chinese Academy of Sciences , Guangzhou 510301 , China
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Selck H, Handy RD, Fernandes TF, Klaine SJ, Petersen EJ. Nanomaterials in the aquatic environment: A European Union-United States perspective on the status of ecotoxicity testing, research priorities, and challenges ahead. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:1055-67. [PMID: 27089437 PMCID: PMC4992942 DOI: 10.1002/etc.3385] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 10/12/2015] [Accepted: 12/21/2015] [Indexed: 05/20/2023]
Abstract
The European Union-United States Communities of Research were established in 2012 to provide a platform for scientists to develop a "shared repertoire of protocols and methods to overcome nanotechnology environmental health and safety (nanoEHS) research gaps and barriers" (www.us-eu.org/). Based on work within the Ecotoxicology Community of Research (2012-2015) the present Focus article provides an overview of the state of the art of nanomaterials (NMs) in the aquatic environment by addressing different research questions, with a focus on ecotoxicological test systems and the challenges faced when assessing NM hazards (e.g., uptake routes, bioaccumulation, toxicity, test protocols, and model organisms). The authors' recommendation is to place particular importance on studying the ecological effects of aged/weathered NMs, as-manufactured NMs, and NMs released from consumer products in addressing the following overarching research topics: 1) NM characterization and quantification in environmental and biological matrices; 2) NM transformation in the environment and consequences for bioavailability and toxicity; 3) alternative methods to assess exposure; 4) influence of exposure scenarios on bioavailability and toxicity; 5) development of more environmentally realistic bioassays; and 6) uptake, internal distribution, and depuration of NMs. Research addressing these key topics will reduce uncertainty in ecological risk assessment and support the sustainable development of nanotechnology.
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Affiliation(s)
- Henriette Selck
- Roskilde University, Dept. of Environmental, Social, and Spatial Change, Denmark
| | - Richard D. Handy
- Plymouth University, School of Biological Sciences, United Kingdom
| | | | - Stephen J. Klaine
- Clemson University, Institute of Environmental Toxicology, USA
- Water Research Group (Ecotoxicology), Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Elijah J. Petersen
- Water Research Group (Ecotoxicology), Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
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EU Regulation of Nanobiocides: Challenges in Implementing the Biocidal Product Regulation (BPR). NANOMATERIALS 2016; 6:nano6020033. [PMID: 28344290 PMCID: PMC5302488 DOI: 10.3390/nano6020033] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 01/28/2016] [Accepted: 02/04/2016] [Indexed: 11/17/2022]
Abstract
The Biocidal Products Regulation (BPR) contains several provisions for nanomaterials (NMs) and is the first regulation in the European Union to require specific testing and risk assessment for the NM form of a biocidal substance as a part of the information requirements. Ecotoxicological data are one of the pillars of the information requirements in the BPR, but there are currently no standard test guidelines for the ecotoxicity testing of NMs. The overall objective of this work was to investigate the implications of the introduction of nano-specific testing requirements in the BPR and to explore how these might be fulfilled in the case of copper oxide nanoparticles. While there is information and data available in the open literature that could be used to fulfill the BPR information requirements, most of the studies do not take the Organisation for Economic Co-operation and Development's nanospecific test guidelines into consideration. This makes it difficult for companies as well as regulators to fulfill the BPR information requirements for nanomaterials. In order to enable a nanospecific risk assessment, best practices need to be developed regarding stock suspension preparation and characterization, exposure suspensions preparation, and for conducting ecotoxicological test.
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Juganson K, Ivask A, Blinova I, Mortimer M, Kahru A. NanoE-Tox: New and in-depth database concerning ecotoxicity of nanomaterials. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:1788-804. [PMID: 26425431 PMCID: PMC4578397 DOI: 10.3762/bjnano.6.183] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 07/30/2015] [Indexed: 05/18/2023]
Abstract
The increasing production and use of engineered nanomaterials (ENMs) inevitably results in their higher concentrations in the environment. This may lead to undesirable environmental effects and thus warrants risk assessment. The ecotoxicity testing of a wide variety of ENMs rapidly evolving in the market is costly but also ethically questionable when bioassays with vertebrates are conducted. Therefore, alternative methods, e.g., models for predicting toxicity mechanisms of ENMs based on their physico-chemical properties (e.g., quantitative (nano)structure-activity relationships, QSARs/QNARs), should be developed. While the development of such models relies on good-quality experimental toxicity data, most of the available data in the literature even for the same test species are highly variable. In order to map and analyse the state of the art of the existing nanoecotoxicological information suitable for QNARs, we created a database NanoE-Tox that is available as Supporting Information File 1. The database is based on existing literature on ecotoxicology of eight ENMs with different chemical composition: carbon nanotubes (CNTs), fullerenes, silver (Ag), titanium dioxide (TiO2), zinc oxide (ZnO), cerium dioxide (CeO2), copper oxide (CuO), and iron oxide (FeO x ; Fe2O3, Fe3O4). Altogether, NanoE-Tox database consolidates data from 224 articles and lists altogether 1,518 toxicity values (EC50/LC50/NOEC) with corresponding test conditions and physico-chemical parameters of the ENMs as well as reported toxicity mechanisms and uptake of ENMs in the organisms. 35% of the data in NanoE-Tox concerns ecotoxicity of Ag NPs, followed by TiO2 (22%), CeO2 (13%), and ZnO (10%). Most of the data originates from studies with crustaceans (26%), bacteria (17%), fish (13%), and algae (11%). Based on the median toxicity values of the most sensitive organism (data derived from three or more articles) the toxicity order was as follows: Ag > ZnO > CuO > CeO2 > CNTs > TiO2 > FeO x . We believe NanoE-Tox database contains valuable information for ENM environmental hazard estimation and development of models for predicting toxic potential of ENMs.
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Affiliation(s)
- Katre Juganson
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
- Department of Chemistry, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
| | - Angela Ivask
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
- Mawson Institute, University of South Australia, Mawson Lakes, 5095 South Australia, Australia
| | - Irina Blinova
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Monika Mortimer
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
- Bren School of Environmental Science & Management, University of California Santa Barbara, Santa Barbara, California 93106-5131, United States
| | - Anne Kahru
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
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Choi S, Kim S, Bae YJ, Park JW, Jung J. Size-dependent toxicity of silver nanoparticles to Glyptotendipes tokunagai. ENVIRONMENTAL HEALTH AND TOXICOLOGY 2015; 30:e2015003. [PMID: 26184045 PMCID: PMC4509522 DOI: 10.5620/eht.e2015003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 04/21/2015] [Indexed: 05/02/2023]
Abstract
OBJECTIVES This study aims to evaluate the size-dependent toxicity of spherical silver nanoparticles (Ag NPs) to an endemic benthic organism, Glyptotendipes tokunagai. METHODS Ag nanoparticles of three nominal sizes (50, 100, and 150 nm) capped with polyvinyl pyrrolidone (PVP-Ag NPs) were used. Their physicochemical properties, acute toxicity (48 hours), and bioaccumulation were measured using third instar larvae of G. tokunagai. RESULTS The aggregation and dissolution of PVP-Ag NPs increased with exposure time and concentration, respectively, particularly for 50 nm PVP-Ag NPs. However, the dissolved concentration of Ag ions was not significant compared with the median lethal concentration value for AgNO3 (3.51 mg/L). The acute toxicity of PVP-Ag NPs was highest for the smallest particles (50 nm), whereas bioaccumulation was greatest for the largest particles (150 nm). However, larger PVP-Ag NPs were absorbed and excreted rapidly, resulting in shorter stays in G. tokunagai than the smaller ones. CONCLUSIONS The size of PVP-Ag NPs significantly affects their acute toxicity to G. tokunagai. In particular, smaller PVP-Ag NPs have a higher solubility and stay longer in the body of G. tokunagai, resulting in higher toxicity than larger PVP-Ag NPs.
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Affiliation(s)
- Seona Choi
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, Korea
| | - Soyoun Kim
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, Korea
| | - Yeon-Jae Bae
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, Korea
| | - June-Woo Park
- Ecotoxicology Research Center, Korea Institute of Toxicology, Daejeon, Korea
| | - Jinho Jung
- Division of Environmental Science and Ecological Engineering, Korea University, Seoul, Korea
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Villarreal FD, Das GK, Abid A, Kennedy IM, Kültz D. Sublethal effects of CuO nanoparticles on Mozambique tilapia (Oreochromis mossambicus) are modulated by environmental salinity. PLoS One 2014; 9:e88723. [PMID: 24520417 PMCID: PMC3919801 DOI: 10.1371/journal.pone.0088723] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 01/10/2014] [Indexed: 11/19/2022] Open
Abstract
The increasing use of manufactured nanoparticles (NP) in different applications has triggered the need to understand their putative ecotoxicological effects in the environment. Copper oxide nanoparticles (CuO NP) are toxic, and induce oxidative stress and other pathophysiological conditions. The unique properties of NP can change depending on the characteristics of the media they are suspended in, altering the impact on their toxicity to aquatic organisms in different environments. Here, Mozambique tilapia (O. mossambicus) were exposed to flame synthesized CuO NP (0.5 and 5 mg·L−1) in two environmental contexts: (a) constant freshwater (FW) and (b) stepwise increase in environmental salinity (SW). Sublethal effects of CuO NP were monitored and used to dermine exposure endpoints. Fish exposed to 5 mg·L−1 CuO in SW showed an opercular ventilation rate increase, whereas fish exposed to 5 mg·L−1 in FW showed a milder response. Different effects of CuO NP on antioxidant enzyme activities, accumulation of transcripts for metal-responsive genes, GSH∶GSSG ratio, and Cu content in fish gill and liver also demonstrate that additive osmotic stress modulates CuO NP toxicity. We conclude that the toxicity of CuO NP depends on the particular environmental context and that salinity is an important factor for modulating NP toxicity in fish.
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Affiliation(s)
- Fernando D. Villarreal
- Department of Animal Science, University of California-Davis, Davis, California, United States of America
- * E-mail:
| | - Gautom Kumar Das
- Department of Mechanical and Aerospace Engineering, University of California-Davis, Davis, California, United States of America
| | - Aamir Abid
- Department of Mechanical and Aerospace Engineering, University of California-Davis, Davis, California, United States of America
| | - Ian M. Kennedy
- Department of Mechanical and Aerospace Engineering, University of California-Davis, Davis, California, United States of America
| | - Dietmar Kültz
- Department of Animal Science, University of California-Davis, Davis, California, United States of America
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