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Rodina D, Roth C, Wohlleben W, Pfohl P. An innovative microplastic extraction technique: The switchable calcium chloride density separation column tested for biodegradable polymers, polyethylene, and polyamide. MethodsX 2024; 12:102560. [PMID: 38292316 PMCID: PMC10825483 DOI: 10.1016/j.mex.2024.102560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/06/2024] [Indexed: 02/01/2024] Open
Abstract
Extracting microplastics from complex matrices poses challenges due to the potential impact of harsh chemical treatments on microplastic properties. For fate and hazard assessment reliable techniques are needed to not only quantify the particle number but also to assess the physicochemical properties of environmental microplastics with minimum changes induced by extraction. Here we present the method development for an innovative and non-destructive extraction protocol based on a switchable calcium chloride density separation column. In contrast to commonly reported extraction protocols, the presented technique is suitable for targeted microplastic property analysis (e.g., surface chemistry and texture) by keeping chemical treatments (such as oxidation and enzymatic digestion) to a minimum. By adjusting the temperature we can control the aggregate state of the highly concentrated salt solution, allowing to separate the microplastics from matrix by cutting of purified, solidified samples. Harsh chemical treatments are avoided, as well as obstruction of microplastic extraction by adsorption to matrix components when passing the tap at the bottom of traditional density separation funnels. The use of microplastics that were prelabeled with a fluorescence dye helped to solve difficulties observed during method development by visual inspection before measurement of extraction efficiency: We spiked a blank compost with low-density polyethylene (LDPE) and polyamide (PA). Additionally, UV aged LDPE was used to demonstrate applicability to more hydrophilic, more environmentally relevant microplastics. The obtained initial results show high recovery of both unaged and aged LDPE over 97 wt.-% and an efficient compost removal but a lower and less robust recovery (between 68 and 18 wt.-%) for PA particles that are more challenging to extract due to an unfortunate synergistic combination of smaller particle size and higher density. Method adaptation to other microplastic types may still be necessary. In short:•A low-cost and simple approach without oxidation to extract (pre-aged) microplastics from compost•Method development by visual observation using fluorescent labelled microplastics and method validation by spike-recovery tests.
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Affiliation(s)
- Darya Rodina
- Department of Chemistry, University of Rochester, Rochester, NY 14627, United States
- BASF SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
| | - Christian Roth
- BASF SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
| | | | - Patrizia Pfohl
- BASF SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
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2
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Pfohl P, Roth C, Wohlleben W. The power of centrifugation: How to extract microplastics from soil with high recovery and matrix removal efficiency. MethodsX 2024; 12:102598. [PMID: 38333546 PMCID: PMC10850752 DOI: 10.1016/j.mex.2024.102598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 01/31/2024] [Indexed: 02/10/2024] Open
Abstract
Understanding the occurrence and transformation of microplastics when released into the environment is essential for risk assessment. The use of biodegradable polymers in agriculture can help to reduce microplastic accumulation in soil, since released fragments of such materials are not persistent and are further transformed into CO2 and biomass (Wohlleben et al., 2023). To be able to monitor the fragmentation and biodegradation of these materials in soil, a validated extraction protocol is needed, which does not induce changes in the chemical and particle properties, additionally it should show high recoveries and matrix removal efficiency. A density-based extraction method in the centrifuge has the potential to remove a high amount of the soil matrix and is very selective for the polymer at the same time. Here we developed an efficient and non-destructive extraction protocol for biodegradable fragments from different soils using sequential centrifugation steps with varying densities and a freezing approach for sample collection. Although the focus of the present study was on biodegradable fragments, the technique can also be used for other types of microplastics with similar or lower density than the one tested for the method validation, but additional recovery tests for the target analyte are recommended.•A density-based extraction method for microplastics from soil, validated by recovery and stability tests using biodegradable polymers•Vessel changes and harsh chemical treatments are kept to a minimum.
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3
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Di Battista V, Ribalta C, Vilsmeier K, Singh D, Demokritou P, Günther E, Jensen KA, Dekkers S, Adam V, Wohlleben W. A Screening Approach to the Safe-and-Sustainable-by-Design Development of Advanced Insulation Materials. Small 2024:e2311155. [PMID: 38516961 DOI: 10.1002/smll.202311155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 02/27/2024] [Indexed: 03/23/2024]
Abstract
Herein, a Safe-and-Sustainable-by-Design (SSbD) screening strategy on four different inorganic aerogel mats and two conventional mineral wools for ranking purposes is demonstrated. Given that they do not consist of particles, the release is first simulated, addressing three occupational exposure scenarios, realistic for their intended use as building insulators. No exposure to consumers nor to the environment is foreseen in the use phase, however, aerosols may be released during mat installation, posing an inhalation risk for workers. All four aerogel mats release more respirable dust than the benchmark materials and 60% thereof deposits in the alveolar region according to modelling tools. The collected aerogel dust allows for subsequent screening of hazard implications via two abiotic assays: 1) surface reactivity in human blood serum; 2) biodissolution kinetics in lung simulant fluids. Both aerogels and conventional insulators show similar surface reactivity. Differences in biodissolution are influenced by the specifically designed organic and inorganic structural modifications. Aerogel mats are better-performing insulators (2-fold lower thermal conductivity than the benchmark) However, this work demonstrates how investment decisions can be balanced with safety and sustainability aspects. Concepts of analogy and similarity thus support easily accessible methods to companies for safe and economically viable innovation with advanced materials.
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Affiliation(s)
- Veronica Di Battista
- Department of Analytical and Material Science and Department of Experimental Toxicology and Ecology, BASF SE, 67063, Ludwigshafen, Germany
- DTU, Department of Environmental and Resource Engineering, Kgs. Lyngby, Denmark
| | - Carla Ribalta
- National Research Centre for the Working Environment, Lerso Parkallé 105, Copenhagen, 2100, Denmark
| | - Klaus Vilsmeier
- Department of Analytical and Material Science and Department of Experimental Toxicology and Ecology, BASF SE, 67063, Ludwigshafen, Germany
| | - Dilpreet Singh
- Center for Nanotechnology and Nanotoxicology, Harvard T.H. Chan School of Public Health, Harvard University, 665 Huntington Ave., Boston, MA, 02115, USA
| | | | - Eva Günther
- BASF Construction Additives GmbH, Dr.-Albert-Frank-Str. 32, 83033, Trostberg, Germany
| | - Keld Alstrup Jensen
- National Research Centre for the Working Environment, Lerso Parkallé 105, Copenhagen, 2100, Denmark
| | - Susan Dekkers
- TNO, Unit Health Living & Work, Risk Analysis for Products in Development, Princetonlaan 6, Utrecht, 3584 CB, The Netherlands
| | - Veronique Adam
- TEMAS Solutions GmbH, Lätterweg 5, Hausen, 5212, Switzerland
| | - Wendel Wohlleben
- Department of Analytical and Material Science and Department of Experimental Toxicology and Ecology, BASF SE, 67063, Ludwigshafen, Germany
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Albergamo V, Wohlleben W, Plata DL. Tracking Dynamic Chemical Reactivity Networks with High-Resolution Mass Spectrometry: A Case of Microplastic-Derived Dissolved Organic Carbon. Environ Sci Technol 2024; 58:4314-4325. [PMID: 38373233 DOI: 10.1021/acs.est.3c08134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
Chemical degradation testing often involves monitoring the loss of a chemical or the evolution of a single diagnostic product through time. Here, we demonstrate a novel approach to tracing complex degradation networks using mass-spectrometry-based methods and open cheminformatics tools. Ester- and ether-based thermoplastic polyurethane (TPU_Ester and TPU_Ether) microplastics (350 μm) and microplastics-derived dissolved organic carbon (MP-DOC) were photoweathered in a simulated marine environment and subsequently analyzed by liquid chromatography coupled to high-resolution mass spectrometry. We formula-annotated 1342 and 2344 unique features in the MP-DOC of TPU_Ester and TPU_Ether, respectively. From these, we extracted 199 and 568 plausible parent-transformation product pairs via matching of features (a) with complementary increasing and decreasing trends (Spearman's correlation coefficient between normalized intensity and time), (b) spectral similarities of at least three accurate mass MS2 fragments, and (c) at least 3 ppm agreement between the theoretical and measured change in m/z between the parent-transformation product formula. Molecular network analysis revealed that both chain scission and cross-linking reactions occur dynamically rather than degradation proceeding in a monotonic progression to smaller or more oxygenated structures. Network nodes with the highest degree of centrality were tentatively identified using in silico fragmentation and can be prioritized for toxicity screening or other physicochemical properties of interest. This work has important implications for chemical transformation tracking in complex mixtures and may someday enable improved elucidation of environmental transformation rules (i.e., structure-reactivity relationships) and fate modeling.
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Affiliation(s)
- Vittorio Albergamo
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Wendel Wohlleben
- Department of Analytical and Material Science, BASF SE, 67056 Ludwigshafen, Germany
| | - Desirée L Plata
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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Di Cristo L, Keller JG, Leoncino L, Marassi V, Loosli F, Seleci DA, Tsiliki G, Oomen AG, Stone V, Wohlleben W, Sabella S. Critical aspects in dissolution testing of nanomaterials in the oro-gastrointestinal tract: the relevance of juice composition for hazard identification and grouping. Nanoscale Adv 2024; 6:798-815. [PMID: 38298600 PMCID: PMC10825926 DOI: 10.1039/d3na00588g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 11/07/2023] [Indexed: 02/02/2024]
Abstract
The dissolution of a nanomaterial (NM) in an in vitro simulant of the oro-gastrointestinal (OGI) tract is an important predictor of its biodurability in vivo. The cascade addition of simulated digestive juices (saliva, stomach and intestine), including inorganic/organic biomacromolecules and digestive enzymes (complete composition, referred to as "Type 1 formulation"), strives for realistic representation of chemical composition of the OGI tract. However, the data robustness requires consideration of analytical feasibility, such as the use of simplified media. Here we present a systematic analysis of the effects exerted by different digestive juice formulations on the dissolution% (or half-life values) of benchmark NMs (e.g., zinc oxide, titanium dioxide, barium sulfate, and silicon dioxide). The digestive juices were progressively simplified by removal of components such as organic molecules, enzymes, and inorganic molecules (Type 2, 3 and 4). The results indicate that the "Type 1 formulation" augments the dissolution via sequestration of ions by measurable factors compared to formulations without enzymes (i.e., Type 3 and 4). Type 1 formulation is thus regarded as a preferable option for predicting NM biodurability for hazard assessment. However, for grouping purposes, the relative similarity among diverse nanoforms (NFs) of a NM is decisive. Two similarity algorithms were applied, and additional case studies comprising NFs and non NFs of the same substance were included. The results support the grouping decision by simplified formulation (Type 3) as a robust method for screening and grouping purposes.
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Affiliation(s)
- Luisana Di Cristo
- Istituto Italiano Di Tecnologia, Nanoregulatory Group, D3PharmaChemistry Genova Italy
| | - Johannes G Keller
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE Ludwigshafen Germany
| | - Luca Leoncino
- Electron Microscopy Facility, Istituto Italiano di Tecnologia Genova Italy
| | | | - Frederic Loosli
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE Ludwigshafen Germany
- University of Vienna Vienna Austria
| | - Didem Ag Seleci
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE Ludwigshafen Germany
| | - Georgia Tsiliki
- Institute for the Management of Information Systems, Athena Research Center Marousi Greece
| | - Agnes G Oomen
- National Institute for Public Health and the Environment (RIVM) Bilthoven The Netherlands
- University of Amsterdam Amsterdam The Netherlands
| | - Vicki Stone
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University Edinburgh UK
| | - Wendel Wohlleben
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE Ludwigshafen Germany
| | - Stefania Sabella
- Istituto Italiano Di Tecnologia, Nanoregulatory Group, D3PharmaChemistry Genova Italy
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Otte JC, Hollnagel HM, Nagel C, Gerhardt RF, Wohlleben W, Vallotton N, Schowanek D, Sanders G, Frasca JM, Mahale T, Pemberton M, Hidding B, Landsiedel R. Three-tiered approach for standard information requirements for polymers requiring registration under REACH. Regul Toxicol Pharmacol 2023; 144:105495. [PMID: 37730194 DOI: 10.1016/j.yrtph.2023.105495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 09/05/2023] [Accepted: 09/13/2023] [Indexed: 09/22/2023]
Abstract
Polymers are a very large class of chemicals comprising often complex molecules with multiple functions used in everyday products. The EU Commission is seeking to develop environmental and human health standard information requirements (SIRs) for man-made polymers requiring registration (PRR) under a revised Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) Regulation. Conventional risk assessment approaches currently used for small molecules may not apply to most polymers. Therefore, we propose a conceptual three-tiered regulatory approach for data generation to assess individual and groups of polymers requiring registration (PRR). A key element is the grouping of polymers according to chemistry, physico-chemical properties and hazard similarity. The limited bioavailability of many polymers is a prominent difference to many small molecules and is a key consideration of the proposed approach. Methods assessing potential for systemic bioavailability are integral to Tier 1. Decisions for further studies are based on considerations of properties and effects, combined with systemic bioavailability and use and exposure considerations. For many PRRs, Tier 1 data on hazard, use and exposure will likely be sufficient for achieving the protection goals of REACH. Vertebrate animal studies in Tiers 2 and 3 can be limited to targeted testing. The outlined approach aims to make use of current best scientific evidence and to reduce animal testing whilst providing data for an adequate level of protection.
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Affiliation(s)
- Jens C Otte
- BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen am Rhein, Germany
| | | | - Christiane Nagel
- BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen am Rhein, Germany
| | | | - Wendel Wohlleben
- BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen am Rhein, Germany
| | | | - Diederik Schowanek
- Procter&Gamble, Brussels Innovation Centre, Temselaan 100, B-1853, Strombeek-Bever, Belgium
| | - Gordon Sanders
- Givaudan International SA, 5, Ch. de la Parfumerie, 1214, Vernier, Switzerland
| | - Joe M Frasca
- ExxonMobil Biomedical Sciences, Inc., Annandale, NJ, USA
| | - Tushar Mahale
- The Lubrizol Corporation, Advanced Materials India Pvt Ltd, 5th, 6th Floor, Jaswanti Landmark, Vikhroli, Mumbai (W), India
| | - Mark Pemberton
- Systox Limited, Sutton, Sutton Grange, Parvey Lane, SK11 0HX, Cheshire, United Kingdom
| | - Bjoern Hidding
- BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen am Rhein, Germany
| | - Robert Landsiedel
- BASF SE, Carl-Bosch-Strasse 38, 67056, Ludwigshafen am Rhein, Germany; Free University of Berlin, Pharmacy, Pharmacology and Toxicology, 14195, Berlin, Germany.
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7
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Hirth S, Wohlleben W, Waindok H. Reply to comment on "which fraction of stone wool fibre surface remains uncoated by binder? A detailed analysis by time-of-flight secondary ion mass spectrometry and X-ray photoelectron spectroscopy" by Hirth et al., 2021, RSC Adv., 11, 39545, DOI: 10.1039/d1ra06251d". RSC Adv 2023; 13:19721-19724. [PMID: 37448780 PMCID: PMC10336475 DOI: 10.1039/d3ra02232c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 05/25/2023] [Indexed: 07/15/2023] Open
Abstract
This is a reply to the Comment of Okhrimenko et al. in the same issue of RSC Advances. We discuss the arguments brought forward by said authors, oppose their objections and show the unchanged validity of our results.
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Affiliation(s)
- Sabine Hirth
- Dept. Materials Physics and Analytics, BASF SE 67056 Ludwigshafen Germany
| | - Wendel Wohlleben
- Dept. Materials Physics and Analytics, BASF SE 67056 Ludwigshafen Germany
| | - Hubert Waindok
- Dept. Materials Physics and Analytics, BASF SE 67056 Ludwigshafen Germany
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8
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Wohlleben W, Mehling A, Landsiedel R. Lessons Learned from the Grouping of Chemicals to Assess Risks to Human Health. Angew Chem Int Ed Engl 2023; 62:e202210651. [PMID: 36254879 DOI: 10.1002/anie.202210651] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 10/15/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022]
Abstract
In analogy to the periodic system that groups elements by their similarity in structure and chemical properties, the hazard of chemicals can be assessed in groups having similar structures and similar toxicological properties. Here we review case studies of chemical grouping strategies that supported the assessment of hazard, exposure, and risk to human health. By the EU-REACH and the US-TSCA New Chemicals Program, structural similarity is commonly used as the basis for grouping, but that criterion is not always adequate and sufficient. Based on the lessons learned, we derive ten principles for grouping, including: transparency of the purpose, criteria, and boundaries of the group; adequacy of methods used to justify the group; and inclusion or exclusion of substances in the group by toxicological properties. These principles apply to initial grouping to prioritize further actions as well as to definitive grouping to generate data for risk assessment. Both can expedite effective risk management.
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Affiliation(s)
- Wendel Wohlleben
- Department of Analytical and Material Science, BASF SE, 67056, Ludwigshafen am Rhein, Germany
- Department of Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany
| | - Annette Mehling
- Dept. of Advanced Formulation and Performance Technology, BASF Personal Care and Nutrition GmbH, 40589, Duesseldorf, Germany
| | - Robert Landsiedel
- Department of Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany
- Free University of Berlin, Biology, Chemistry and Pharmacy-Pharmacology and Toxicology, 14195, Berlin, Germany
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9
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Albergamo V, Wohlleben W, Plata DL. Photochemical weathering of polyurethane microplastics produced complex and dynamic mixtures of dissolved organic chemicals. Environ Sci Process Impacts 2023; 25:432-444. [PMID: 36691826 DOI: 10.1039/d2em00415a] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Sunlight exposure can naturally mitigate microplastics pollution in the surface ocean, however it results in emissions of dissolved organic carbon (DOC) whose characteristics and fate remain largely unknown. In this work, we investigated the effects of solar radiation on polyether (TPU_Ether) and polyester (TPU_Ester) thermoplastic polyurethane, and on a thermoset polyurethane (PU_Hardened). The microplastics were irradiated with simulated solar light with a UV dose of 350 MJ m-2, which corresponds to roughly 15 months outdoor exposure at 31° N latitude. The particles were characterized using ATR-FTIR and elemental analysis. The DOC released to the aqueous phase was quantified by total organic carbon analysis and characterized by nontarget liquid chromatography coupled to high-resolution mass spectrometry. Polyurethane microplastics were degraded following mechanisms reconcilable with UV photo-oxidation. The carbon mass fraction released to the aqueous phase was 8.5 ± 0.5%, 3.7 ± 0.2%, and 2.8 ± 0.2% for TPU_Ether, TPU_Ester, and PU_Hardened, respectively. The corresponding DOC release rates, expressed as mg carbon per UV dose were 0.023, 0.013, and 0.010 mg MJ-1 for TPU_Ether, TPU_Ester and PU_Hardened, respectively. Roughly three thousand unique by-products were released from photo-weathered TPUs, whereas 540 were detected in the DOC of PU_Hardened. This carbon pool was highly complex and dynamic in terms of physicochemical properties and susceptibility to further photodegradation after dissolution from the particles. Our results show that plastics photodegradation in the ocean requires chemical assessment of the DOC emissions in addition to the analysis of aged microplastics and that polymer chemistry influences the chain scission products.
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Affiliation(s)
- Vittorio Albergamo
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 15 Vassar Street, Cambridge, Massachusetts 02139, USA.
| | - Wendel Wohlleben
- Department of Material Physics and Analytics, Advanced Materials Research, BASF SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
- Department of Experimental Toxicology and Ecology, Advanced Materials Research, BASF SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
| | - Desirée L Plata
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 15 Vassar Street, Cambridge, Massachusetts 02139, USA.
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Brüngel R, Rückert J, Müller P, Babick F, Friedrich CM, Ghanem A, Hodoroaba VD, Mech A, Weigel S, Wohlleben W, Rauscher H. NanoDefiner Framework and e-Tool Revisited According to the European Commission's Nanomaterial Definition 2022/C 229/01. Nanomaterials (Basel) 2023; 13:990. [PMID: 36985884 PMCID: PMC10056892 DOI: 10.3390/nano13060990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/28/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
The new recommended definition of a nanomaterial, 2022/C 229/01, adopted by the European Commission in 2022, will have a considerable impact on European Union legislation addressing chemicals, and therefore tools to implement this new definition are urgently needed. The updated NanoDefiner framework and its e-tool implementation presented here are such instruments, which help stakeholders to find out in a straightforward way whether a material is a nanomaterial or not. They are two major outcomes of the NanoDefine project, which is explicitly referred to in the new definition. This work revisits the framework and e-tool, and elaborates necessary adjustments to make these outcomes applicable for the updated recommendation. A broad set of case studies on representative materials confirms the validity of these adjustments. To further foster the sustainability and applicability of the framework and e-tool, measures for the FAIRification of expert knowledge within the e-tool's knowledge base are elaborated as well. The updated framework and e-tool are now ready to be used in line with the updated recommendation. The presented approach may serve as an example for reviewing existing guidance and tools developed for the previous definition 2011/696/EU, particularly those adopting NanoDefine project outcomes.
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Affiliation(s)
- Raphael Brüngel
- Department of Computer Science, University of Applied Sciences and Arts Dortmund (FH Dortmund), 44227 Dortmund, Germany
- Institute for Medical Informatics, Biometry and Epidemiology (IMIBE), University Hospital Essen, 45122 Essen, Germany
- Institute for Artificial Intelligence in Medicine (IKIM), University Hospital Essen, 45131 Essen, Germany
| | - Johannes Rückert
- Department of Computer Science, University of Applied Sciences and Arts Dortmund (FH Dortmund), 44227 Dortmund, Germany
| | - Philipp Müller
- Analytical and Material Science, BASF SE, 67056 Ludwigshafen, Germany
| | - Frank Babick
- Institute of Process Engineering and Environmental Technology, Technische Universität Dresden (TU Dresden), 01062 Dresden, Germany
| | - Christoph M. Friedrich
- Department of Computer Science, University of Applied Sciences and Arts Dortmund (FH Dortmund), 44227 Dortmund, Germany
- Institute for Medical Informatics, Biometry and Epidemiology (IMIBE), University Hospital Essen, 45122 Essen, Germany
| | - Antoine Ghanem
- R&I Centre Brussels, Solvay S.A., 1120 Brussels, Belgium
| | - Vasile-Dan Hodoroaba
- Division 6.1 Surface Analysis and Interfacial Chemistry, Bundesanstalt für Materialforschung und -prüfung (BAM), 12205 Berlin, Germany
| | - Agnieszka Mech
- European Commission, Joint Research Centre (JRC), 21027 Ispra, Italy
| | - Stefan Weigel
- Department Safety in the Food Chain, German Federal Institute for Risk Assessment (BfR), 10589 Berlin, Germany
| | - Wendel Wohlleben
- Analytical and Material Science, BASF SE, 67056 Ludwigshafen, Germany
| | - Hubert Rauscher
- European Commission, Joint Research Centre (JRC), 21027 Ispra, Italy
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11
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Murphy FA, Johnston HJ, Dekkers S, Bleeker EAJ, Oomen AG, Fernandes TF, Rasmussen K, Jantunen P, Rauscher H, Hunt N, di Cristo L, Braakhuis HM, Haase A, Hristozov D, Wohlleben W, Sabella S, Stone V. How to formulate hypotheses and IATAs to support grouping and read-across of nanoforms. ALTEX 2023; 40:125-140. [PMID: 35796348 DOI: 10.14573/altex.2203241] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 06/20/2022] [Indexed: 01/20/2023]
Abstract
Manufacturing and functionalizing materials at the nanoscale has led to the generation of a whole array of nanoforms (NFs) of substances varying in size, morphology, and surface characteristics. Due to financial, time, and ethical considerations, testing every unique NF for adverse effects is virtually impossible. Use of hypothesis-driven grouping and read-across approaches, as supported by the GRACIOUS Framework, represents a promising alternative to case-by-case testing that will make the risk assessment process more efficient. Through application of appropriate grouping hypotheses, the Framework facilitates the assessment of similarity between NFs, thereby supporting grouping and read-across of information, minimizing the need for new testing, and aligning with the 3R principles of replacement, reduction, and refinement of animals in toxicology studies. For each grouping hypothesis an integrated approach to testing and assessment (IATA) guides the user in data gathering and acquisition to test the hypothesis, following a structured format to facilitate efficient decision-making. Here we present the template used to generate the GRACIOUS grouping hypotheses encompassing information relevant to “Lifecycle, environmental release, and human exposure”, “What they are: physicochemical characteristics”, “Where they go: environmental fate, uptake, and toxicokinetics”, and “What they do: human and environmental toxicity”. A summary of the template-derived hypotheses focusing on human health is provided, along with an overview of the IATAs generated by the GRACIOUS project. We discuss the application and flexibility of the template, providing the opportunity to expand the application of grouping and read-across in a logical, evidence-based manner to a wider range of NFs and substances.
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Affiliation(s)
- Fiona A Murphy
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, UK
| | - Helinor J Johnston
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, UK
| | - Susan Dekkers
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Eric A J Bleeker
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Agnes G Oomen
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.,Institute for Biodiversity & Ecosystem Dynamics (IBED), Faculty of Science, University of Amsterdam, Amsterdam, The Netherlands
| | - Teresa F Fernandes
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, UK
| | | | - Paula Jantunen
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Hubert Rauscher
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Neil Hunt
- Yordas Group, Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Luisana di Cristo
- Nanoregulatory Group, Drug Discovery and Development Department, Italian Institute of Technology, Genova, Italy
| | - Hedwig M Braakhuis
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Andrea Haase
- German Federal Institute for Risk Assessment (BfR), Department of Chemicals and Product Safety, Berlin, Germany
| | | | - Wendel Wohlleben
- BASF SE, Dept. Material Physics and Dept of Experimental Toxicology & Ecology, Ludwigshafen, Germany
| | - Stefania Sabella
- Nanoregulatory Group, Drug Discovery and Development Department, Italian Institute of Technology, Genova, Italy
| | - Vicki Stone
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh, UK
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12
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Keller JG, Persson M, Müller P, Ma-Hock L, Werle K, Arts J, Landsiedel R, Wohlleben W. Corrigendum to variation in dissolution behavior among different nanoforms and its implication for grouping approaches in inhalation toxicity [NanoImpact 23 (2021) 100341]. NanoImpact 2023; 29:100455. [PMID: 36801377 DOI: 10.1016/j.impact.2023.100455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Affiliation(s)
- Johannes G Keller
- BASF SE, Department Experimental Toxicology and Ecology, and Department Material Physics, Ludwigshafen 67056, Germany.
| | - Michael Persson
- Nouryon Pulp and Performance Chemicals AB, Bohus S-445 80, Sweden.
| | - Philipp Müller
- BASF SE, Department Experimental Toxicology and Ecology, and Department Material Physics, Ludwigshafen 67056, Germany.
| | - Lan Ma-Hock
- BASF SE, Department Experimental Toxicology and Ecology, and Department Material Physics, Ludwigshafen 67056, Germany
| | - Kai Werle
- BASF SE, Department Experimental Toxicology and Ecology, and Department Material Physics, Ludwigshafen 67056, Germany.
| | - Josje Arts
- Nouryon Pulp and Performance Chemicals AB, Bohus S-445 80, Sweden.
| | - Robert Landsiedel
- BASF SE, Department Experimental Toxicology and Ecology, and Department Material Physics, Ludwigshafen 67056, Germany.
| | - Wendel Wohlleben
- BASF SE, Department Experimental Toxicology and Ecology, and Department Material Physics, Ludwigshafen 67056, Germany.
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13
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Pfohl P, Bahl D, Rückel M, Wagner M, Meyer L, Bolduan P, Battagliarin G, Hüffer T, Zumstein M, Hofmann T, Wohlleben W. Effect of Polymer Properties on the Biodegradation of Polyurethane Microplastics. Environ Sci Technol 2022; 56:16873-16884. [PMID: 36394826 PMCID: PMC9731262 DOI: 10.1021/acs.est.2c05602] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/19/2022] [Accepted: 10/26/2022] [Indexed: 06/01/2023]
Abstract
The release of fragments from plastic products, that is, secondary microplastics, is a major concern in the context of the global plastic pollution. Currently available (thermoplastic) polyurethanes [(T)PU] are not biodegradable and therefore should be recycled. However, the ester bond in (T)PUs might be sufficiently hydrolysable to enable at least partial biodegradation of polyurethane particles. Here, we investigated biodegradation in compost of different types of (T)PU to gain insights into their fragmentation and biodegradation mechanisms. The studied (T)PUs varied regarding the chemistry of their polymer backbone (aromatic/aliphatic), hard phase content, cross-linking degree, and presence of a hydrolysis-stabilizing additive. We developed and validated an efficient and non-destructive polymer particle extraction process for partially biodegraded (T)PUs based on ultrasonication and density separation. Our results showed that biodegradation rates and extents decreased with increasing cross-linking density and hard-segment content. We found that the presence of a hydrolysis stabilizer reduced (T)PU fragmentation while not affecting the conversion of (T)PU carbon into CO2. We propose a biodegradation mechanism for (T)PUs that includes both mother particle shrinkage by surface erosion and fragmentation. The presented results help to understand structure-degradation relationships of (T)PUs and support recycling strategies.
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Affiliation(s)
- Patrizia Pfohl
- BASF
SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
- Centre
for Microbiology and Environmental Systems Science, University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
- Doctoral
School in Microbiology and Environmental Science, University of Vienna, Vienna 1030, Austria
| | - Daniel Bahl
- BASF
SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
| | - Markus Rückel
- BASF
SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
| | - Marion Wagner
- BASF
SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
| | - Lars Meyer
- BASF
SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany
| | | | | | - Thorsten Hüffer
- Centre
for Microbiology and Environmental Systems Science, University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
| | - Michael Zumstein
- Centre
for Microbiology and Environmental Systems Science, University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
| | - Thilo Hofmann
- Centre
for Microbiology and Environmental Systems Science, University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
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14
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Di Cristo L, Ude VC, Tsiliki G, Tatulli G, Romaldini A, Murphy F, Wohlleben W, Oomen AG, Pompa PP, Arts J, Stone V, Sabella S. Grouping of orally ingested silica nanomaterials via use of an integrated approach to testing and assessment to streamline risk assessment. Part Fibre Toxicol 2022; 19:68. [PMID: 36461106 PMCID: PMC9719179 DOI: 10.1186/s12989-022-00508-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 11/21/2022] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Nanomaterials can exist in different nanoforms (NFs). Their grouping may be supported by the formulation of hypotheses which can be interrogated via integrated approaches to testing and assessment (IATA). IATAs are decision trees that guide the user through tiered testing strategies (TTS) to collect the required evidence needed to accept or reject a grouping hypothesis. In the present paper, we investigated the applicability of IATAs for ingested NFs using a case study that includes different silicon dioxide, SiO2 NFs. Two oral grouping hypotheses addressing local and systemic toxicity were identified relevant for the grouping of these NFs and verified through the application of oral IATAs. Following different Tier 1 and/or Tier 2 in vitro methods of the TTS (i.e., in vitro dissolution, barrier integrity and inflammation assays), we generated the NF datasets. Furthermore, similarity algorithms (e.g., Bayesian method and Cluster analysis) were utilized to identify similarities among the NFs and establish a provisional group(s). The grouping based on Tier 1 and/or Tier 2 testing was analyzed in relation to available Tier 3 in vivo data in order to verify if the read-across was possible and therefore support a grouping decision. RESULTS The measurement of the dissolution rate of the silica NFs in the oro-gastrointestinal tract and in the lysosome identified them as gradually dissolving and biopersistent NFs. For the local toxicity to intestinal epithelium (e.g. cytotoxicity, membrane integrity and inflammation), the biological results of the gastrointestinal tract models indicate that all of the silica NFs were similar with respect to the lack of local toxicity and, therefore, belong to the same group; in vivo data (although limited) confirmed the lack of local toxicity of NFs. For systemic toxicity, Tier 1 data did not identify similarity across the NFs, with results across different decision nodes being inconsistent in providing homogeneous group(s). Moreover, the available Tier 3 in vivo data were also insufficient to support decisions based upon the obtained in vitro results and relating to the toxicity of the tested NFs. CONCLUSIONS The information generated by the tested oral IATAs can be effectively used for similarity assessment to support a grouping decision upon the application of a hypothesis related to toxicity in the gastrointestinal tract. The IATAs facilitated a structured data analysis and, by means of the expert's interpretation, supported read-across with the available in vivo data. The IATAs also supported the users in decision making, for example, reducing the testing when the grouping was well supported by the evidence and/or moving forward to advanced testing (e.g., the use of more suitable cellular models or chronic exposure) to improve the confidence level of the data and obtain more focused information.
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Affiliation(s)
- Luisana Di Cristo
- grid.25786.3e0000 0004 1764 2907D3 PharmaChemistry, Nanoregulatory Group, Italian Institute of Technology, Via Morego, 30, 16163 Genoa, Italy
| | - Victor C. Ude
- grid.9531.e0000000106567444Nano Safety Research Group, School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh, EH14 4AS UK
| | - Georgia Tsiliki
- grid.19843.370000 0004 0393 5688Institute for the Management of Information Systems, Athena Research Center, Marousi, Greece
| | - Giuseppina Tatulli
- grid.25786.3e0000 0004 1764 2907Nanobiointeractions & Nanodiagnostics, Istituto Italiano Di Tecnologia (IIT), Via Morego, 30, 16163 Genoa, Italy
| | - Alessio Romaldini
- grid.25786.3e0000 0004 1764 2907D3 PharmaChemistry, Nanoregulatory Group, Italian Institute of Technology, Via Morego, 30, 16163 Genoa, Italy
| | - Fiona Murphy
- grid.9531.e0000000106567444Nano Safety Research Group, School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh, EH14 4AS UK
| | - Wendel Wohlleben
- grid.3319.80000 0001 1551 0781Department Material Physics and Department of Experimental Toxicology & Ecology, BASF SE, Ludwigshafen, Germany
| | - Agnes G. Oomen
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands ,grid.7177.60000000084992262Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Pier P. Pompa
- grid.25786.3e0000 0004 1764 2907Nanobiointeractions & Nanodiagnostics, Istituto Italiano Di Tecnologia (IIT), Via Morego, 30, 16163 Genoa, Italy
| | | | - Vicki Stone
- grid.9531.e0000000106567444Nano Safety Research Group, School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh, EH14 4AS UK
| | - Stefania Sabella
- grid.25786.3e0000 0004 1764 2907D3 PharmaChemistry, Nanoregulatory Group, Italian Institute of Technology, Via Morego, 30, 16163 Genoa, Italy
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15
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Wohlleben W, Mehling A, Landsiedel R. Lessons Learned from the Grouping of Chemicals to Assess Risks to Human Health. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202210651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Wendel Wohlleben
- BASF SE Material Physics Carl Bosch Str. 67056 Ludwigshafen GERMANY
| | - Annette Mehling
- BASF Personal Care and Nutrition GmbH Advanced Formulation and Performance Technology 40589 Düsseldorf GERMANY
| | - Robert Landsiedel
- BASF SE Experimental Toxicology and Ecology Carl Bosch Str. 38 67056 Ludwigshafen GERMANY
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16
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Tschiche HR, Bierkandt FS, Creutzenberg O, Fessard V, Franz R, Greiner R, Gruber-Traub C, Haas KH, Haase A, Hartwig A, Hesse B, Hund-Rinke K, Iden P, Kromer C, Loeschner K, Mutz D, Rakow A, Rasmussen K, Rauscher H, Richter H, Schoon J, Schmid O, Som C, Spindler LM, Tovar GEM, Westerhoff P, Wohlleben W, Luch A, Laux P. Analytical and toxicological aspects of nanomaterials in different product groups: Challenges and opportunities. NanoImpact 2022; 28:100416. [PMID: 35995388 DOI: 10.1016/j.impact.2022.100416] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 07/15/2022] [Accepted: 08/14/2022] [Indexed: 06/15/2023]
Abstract
The widespread integration of engineered nanomaterials into consumer and industrial products creates new challenges and requires innovative approaches in terms of design, testing, reliability, and safety of nanotechnology. The aim of this review article is to give an overview of different product groups in which nanomaterials are present and outline their safety aspects for consumers. Here, release of nanomaterials and related analytical challenges and solutions as well as toxicological considerations, such as dose-metrics, are discussed. Additionally, the utilization of engineered nanomaterials as pharmaceuticals or nutraceuticals to deliver and release cargo molecules is covered. Furthermore, critical pathways for human exposure to nanomaterials, namely inhalation and ingestion, are discussed in the context of risk assessment. Analysis of NMs in food, innovative medicine or food contact materials is discussed. Specific focus is on the presence and release of nanomaterials, including whether nanomaterials can migrate from polymer nanocomposites used in food contact materials. With regard to the toxicology and toxicokinetics of nanomaterials, aspects of dose metrics of inhalation toxicity as well as ingestion toxicology and comparison between in vitro and in vivo conclusions are considered. The definition of dose descriptors to be applied in toxicological testing is emphasized. In relation to potential exposure from different products, opportunities arising from the use of advanced analytical techniques in more unique scenarios such as release of nanomaterials from medical devices such as orthopedic implants are addressed. Alongside higher product performance and complexity, further challenges regarding material characterization and safety, as well as acceptance by the general public are expected.
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Affiliation(s)
- Harald R Tschiche
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany.
| | - Frank S Bierkandt
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Otto Creutzenberg
- Fraunhofer Institute for Toxicology and Experimental Medicine (ITEM), Hannover, Germany
| | - Valerie Fessard
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Fougères Laboratory, Toxicology of contaminants Unit, Fougères, France
| | - Roland Franz
- Fraunhofer Institute for Process Engineering and Packaging (IVV), Freising, Germany
| | - Ralf Greiner
- Department of Food Technology and Bioprocess Engineering, Max Rubner-Institut, Karlsruhe, Germany
| | - Carmen Gruber-Traub
- Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB), Stuttgart, Germany
| | - Karl-Heinz Haas
- Fraunhofer Institute for Silicate Research (ISC), Würzburg, Germany
| | - Andrea Haase
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Andrea Hartwig
- Karlsruhe Institute of Technology (KIT), Institute of Applied Biosciences (IAB), Food Chemistry and Toxicology, Germany
| | - Bernhard Hesse
- European Synchrotron Radiation Facility, Grenoble, France
| | - Kerstin Hund-Rinke
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Schmallenberg, Germany
| | | | - Charlotte Kromer
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Katrin Loeschner
- National Food Institute, Technical University of Denmark, Lyngby, Denmark
| | - Diana Mutz
- German Federal Institute for Risk Assessment (BfR), Research Strategy and Coordination, Berlin, Germany
| | - Anastasia Rakow
- Charité - Universitätsmedizin Berlin, Center for Musculoskeletal Surgery, Berlin, Germany; Center for Orthopaedics, Trauma Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald, Germany
| | | | - Hubert Rauscher
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Hannes Richter
- Fraunhofer IKTS - Institute for Ceramic Technologies and Systems, Hermsdorf, Germany
| | - Janosch Schoon
- Center for Orthopaedics, Trauma Surgery and Rehabilitation Medicine, University Medicine Greifswald, Greifswald, Germany; Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
| | - Otmar Schmid
- Comprehensive Pneumology Center (CPC-M), Member of the German Center for Lung Research (DZL), Munich, Germany; Institute of Lung Health and Immunity, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Claudia Som
- Technology and Society Laboratory, Swiss Federal Laboratories for Materials Science and Technology (Empa), St. Gallen, Switzerland
| | - Lena M Spindler
- Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB), Stuttgart, Germany; University of Stuttgart, Institute of Interfacial Process Engineering and Plasma Technology (IGVP), Stuttgart, Germany
| | - Günter E M Tovar
- Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB), Stuttgart, Germany; University of Stuttgart, Institute of Interfacial Process Engineering and Plasma Technology (IGVP), Stuttgart, Germany
| | - Paul Westerhoff
- Arizona State University, Tempe, AZ, United States of America
| | | | - Andreas Luch
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Peter Laux
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
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17
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Wohlleben W, Stone V. Editorial to the special issue on "similarity assessment of nanoforms: Concepts, tools and case studies of the GRACIOUS project". NanoImpact 2022; 28:100443. [PMID: 36427811 DOI: 10.1016/j.impact.2022.100443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Affiliation(s)
- Wendel Wohlleben
- BASF SE, Dept. Material Physics and Dept Experimental Toxicology & Ecology, Ludwigshafen, Germany.
| | - Vicki Stone
- NanoSafety Research Group, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, UK.
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18
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Pfohl P, Wagner M, Meyer L, Domercq P, Praetorius A, Hüffer T, Hofmann T, Wohlleben W. Environmental Degradation of Microplastics: How to Measure Fragmentation Rates to Secondary Micro- and Nanoplastic Fragments and Dissociation into Dissolved Organics. Environ Sci Technol 2022; 56:11323-11334. [PMID: 35902073 PMCID: PMC9387529 DOI: 10.1021/acs.est.2c01228] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Understanding the environmental fate of microplastics is essential for their risk assessment. It is essential to differentiate size classes and degradation states. Still, insights into fragmentation and degradation mechanisms of primary and secondary microplastics into micro- and nanoplastic fragments and other degradation products are limited. Here, we present an adapted NanoRelease protocol for a UV-dose-dependent assessment and size-selective quantification of the release of micro- and nanoplastic fragments down to 10 nm and demonstrate its applicability for polyamide and thermoplastic polyurethanes. The tested cryo-milled polymers do not originate from actual consumer products but are handled in industry and are therefore representative of polydisperse microplastics occurring in the environment. The protocol is suitable for various types of microplastic polymers, and the measured rates can serve to parameterize mechanistic fragmentation models. We also found that primary microplastics matched the same ranking of weathering stability as their corresponding macroplastics and that dissolved organics constitute a major rate of microplastic mass loss. The results imply that previously formed micro- and nanoplastic fragments can further degrade into water-soluble organics with measurable rates that enable modeling approaches for all environmental compartments accessible to UV light.
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Affiliation(s)
- Patrizia Pfohl
- BASF
SE, Carl-Bosch-Str. 38, Ludwigshafen 67056, Germany
- Department
of Environmental Geosciences, Centre for Microbiology and Environmental
Systems Science, University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
- Doctoral
School in Microbiology and Environmental Science, University of Vienna, Vienna 1030, Austria
| | - Marion Wagner
- BASF
SE, Carl-Bosch-Str. 38, Ludwigshafen 67056, Germany
| | - Lars Meyer
- BASF
SE, Carl-Bosch-Str. 38, Ludwigshafen 67056, Germany
| | - Prado Domercq
- Department
of Environmental Science, Stockholm University, Stockholm 10691, Sweden
| | - Antonia Praetorius
- Institute
for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam 1090 GE, Netherlands
| | - Thorsten Hüffer
- Department
of Environmental Geosciences, Centre for Microbiology and Environmental
Systems Science, University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
- Research
Platform Plastics in the Environment and Society (PLENTY), University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
| | - Thilo Hofmann
- Department
of Environmental Geosciences, Centre for Microbiology and Environmental
Systems Science, University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
- Research
Platform Plastics in the Environment and Society (PLENTY), University of Vienna, Josef-Holaubek-Platz 2, Vienna 1090, Austria
| | - Wendel Wohlleben
- BASF
SE, Carl-Bosch-Str. 38, Ludwigshafen 67056, Germany
- . Tel.: +49 621 6095339
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19
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Cross RK, Bossa N, Stolpe B, Loosli F, Sahlgren NM, Clausen PA, Delpivo C, Persson M, Valsesia A, Ponti J, Mehn D, Seleci DA, Müller P, von der Kammer F, Rauscher H, Spurgeon D, Svendsen C, Wohlleben W. Reproducibility of methods required to identify and characterize nanoforms of substances. NanoImpact 2022; 27:100410. [PMID: 35787478 DOI: 10.1016/j.impact.2022.100410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 06/24/2022] [Accepted: 06/25/2022] [Indexed: 06/15/2023]
Abstract
Nanoforms (NFs) of a substance may be distinguished from one another through differences in their physicochemical properties. When registering nanoforms of a substance for assessment under the EU REACH framework, five basic descriptors are required for their identification: composition, surface chemistry, size, specific surface area and shape. To make the risk assessment of similar NFs efficient, a number of grouping frameworks have been proposed, which often require assessment of similarity on individual physicochemical properties as part of the group justification. Similarity assessment requires an understanding of the achievable accuracy of the available methods. It must be demonstrated that measured differences between NFs are greater than the achievable accuracy of the method, to have confidence that the measured differences are indeed real. To estimate the achievable accuracy of a method, we assess the reproducibility of six analytical techniques routinely used to measure these five basic descriptors of nanoforms: inductively coupled plasma mass spectrometry (ICP-MS), Thermogravimetric analysis (TGA), Electrophoretic light scattering (ELS), Brunauer-Emmett-Teller (BET) specific surface area and transmission and scanning electron microscopy (TEM and SEM). Assessment was performed on representative test materials to evaluate the reproducibility of methods on single NFs of substances. The achievable accuracy was defined as the relative standard deviation of reproducibility (RSDR) for each method. Well established methods such as ICP-MS quantification of metal impurities, BET measurements of specific surface area, TEM and SEM for size and shape and ELS for surface potential and isoelectric point, all performed well, with low RSDR, generally between 5 and 20%, with maximal fold differences usually <1.5 fold between laboratories. Applications of technologies such as TGA for measuring water content and putative organic impurities, additives or surface treatments (through loss on ignition), which have a lower technology readiness level, demonstrated poorer reproducibility, but still within 5-fold differences. The expected achievable accuracy of ICP-MS may be estimated for untested analytes using established relationships between concentration and reproducibility, but this is not yet the case for TGA measurements of loss on ignition or water content. The results here demonstrate an approach to estimate the achievable accuracy of a method that should be employed when interpreting differences between NFs on individual physicochemical properties.
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Affiliation(s)
- Richard K Cross
- UK Centre for Ecology and Hydrology, Pollution, Wallingford, Oxfordshire, United Kingdom.
| | - Nathan Bossa
- LEITAT Technological Center, Carrer de la Innovació 2, 08225 Terrassa, Barcelona, Spain
| | | | - Frédéric Loosli
- Environmental Geosciences, Centre for Microbiology and Environmental Systems Science, University of Vienna, Wien, Austria
| | | | - Per Axel Clausen
- The National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Camilla Delpivo
- LEITAT Technological Center, Carrer de la Innovació 2, 08225 Terrassa, Barcelona, Spain
| | | | - Andrea Valsesia
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Jessica Ponti
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Dora Mehn
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Didem Ag Seleci
- BASF SE, Department of Material Physics and Department of Experimental Toxicology & Ecology, Ludwigshafen, Germany
| | - Philipp Müller
- BASF SE, Department of Material Physics and Department of Experimental Toxicology & Ecology, Ludwigshafen, Germany
| | - Frank von der Kammer
- Environmental Geosciences, Centre for Microbiology and Environmental Systems Science, University of Vienna, Wien, Austria
| | - Hubert Rauscher
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Dave Spurgeon
- UK Centre for Ecology and Hydrology, Pollution, Wallingford, Oxfordshire, United Kingdom
| | - Claus Svendsen
- UK Centre for Ecology and Hydrology, Pollution, Wallingford, Oxfordshire, United Kingdom
| | - Wendel Wohlleben
- BASF SE, Department of Material Physics and Department of Experimental Toxicology & Ecology, Ludwigshafen, Germany
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20
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Zanoni I, Keller JG, Sauer UG, Müller P, Ma-Hock L, Jensen KA, Costa AL, Wohlleben W. Dissolution Rate of Nanomaterials Determined by Ions and Particle Size under Lysosomal Conditions: Contributions to Standardization of Simulant Fluids and Analytical Methods. Chem Res Toxicol 2022; 35:963-980. [PMID: 35593714 PMCID: PMC9215348 DOI: 10.1021/acs.chemrestox.1c00418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Indexed: 01/08/2023]
Abstract
Dissolution of inhaled engineered nanomaterials (ENM) under physiological conditions is essential to predict the clearance of the ENM from the lungs and to assess their biodurability and the potential effects of released ions. Alveolar macrophage (AM) lysosomes contain a pH 4.5 saline brine with enzymes and other components. Different types of artificial phagolysosomal simulant fluids (PSFs) have been developed for dissolution testing, but the consequence of using different media is not known. In this study, we tested to which extent six fundamentally different PSFs affected the ENM dissolution kinetics and particle size as determined by a validated transmission electron microscopy (TEM) image analysis. Three lysosomal simulant media were consistent with each other and with in vivo clearance. These media predict the quick dissolution of ZnO, the partial dissolution of SiO2, and the very slow dissolution of TiO2. The valid media use either a mix of organic acids (with the total concentration below 0.5 g/L, thereof citric acid below 0.15 g/L) or another organic acid (KH phthalate). For several ENM, including ZnO, BaSO4, and CeO2, all these differences induce only minor modulation of the dissolution rates. Only for TiO2 and SiO2, the interaction with specific organic acids is highly sensitive, probably due to sequestration of the ions, and can lead to wrong predictions when compared to the in vivo behavior. The media that fail on TiO2 and SiO2 dissolution use citric acid at concentrations above 5 g/L (up to 28 g/L). In the present selection of ENM, fluids, and methods, the different lysosomal simulant fluids did not induce changes of particle morphology, except for small changes in SiO2 and BaSO4 particles most likely due to ion dissolution, reprecipitation, and coalescence between neighboring particles. Based on the current evidence, the particle size by TEM analysis is not a sufficiently sensitive analytical method to deduce the rate of ENM dissolution in physiological media. In summary, we recommend the standardization of ENM dissolution testing by one of the three valid lysosomal simulant fluids with determination of the dissolution rate and halftime by the quantification of ions. This recommendation was established for a continuous flow system but may be relevant as well for static (batch) solubility testing.
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Affiliation(s)
- Ilaria Zanoni
- CNR-ISTEC-National
Research Council of Italy, Institute of
Science and Technology for Ceramics, Faenza 48018, Italy
| | - Johannes G. Keller
- Department
of Material Physics and Analytics, BASF
SE, Ludwigshafen 67056, Germany
- Department
of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen 67056, Germany
| | - Ursula G. Sauer
- Scientific
Consultancy-Animal Welfare, Neubiberg 85579, Germany
| | - Philipp Müller
- Department
of Material Physics and Analytics, BASF
SE, Ludwigshafen 67056, Germany
| | - Lan Ma-Hock
- Department
of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen 67056, Germany
| | - Keld A. Jensen
- National
Research Centre for Work Environment (NRCWE), Copenhagen 2100, Denmark
| | - Anna Luisa Costa
- CNR-ISTEC-National
Research Council of Italy, Institute of
Science and Technology for Ceramics, Faenza 48018, Italy
| | - Wendel Wohlleben
- Department
of Material Physics and Analytics, BASF
SE, Ludwigshafen 67056, Germany
- Department
of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen 67056, Germany
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21
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Di Cristo L, Janer G, Dekkers S, Boyles M, Giusti A, Keller JG, Wohlleben W, Braakhuis H, Ma-Hock L, Oomen AG, Haase A, Stone V, Murphy F, Johnston HJ, Sabella S. Integrated approaches to testing and assessment for grouping nanomaterials following dermal exposure. Nanotoxicology 2022; 16:310-332. [PMID: 35704509 DOI: 10.1080/17435390.2022.2085207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Exposure to different nanoforms (NFs) via the dermal route is expected in occupational and consumer settings and thus it is important to assess their dermal toxicity and the contribution of dermal exposure to systemic bioavailability. We have formulated four grouping hypotheses for dermal toxicity endpoints which allow NFs to be grouped to streamline and facilitate risk assessment. The grouping hypotheses are developed based on insight into how physicochemical properties of NFs (i.e. composition, dissolution kinetics, size, and flexibility) influence their fate and hazard following dermal exposure. Each hypothesis is accompanied by a tailored Integrated Approach to Testing and Assessment (IATA) that is structured as a decision tree and tiered testing strategies (TTS) for each relevant question (at decision nodes) that indicate what information is needed to guide the user to accept or reject the grouping hypothesis. To develop these hypotheses and IATAs, we gathered and analyzed existing information on skin irritation, skin sensitization, and dermal penetration of NFs from the published literature and performed experimental work to generate data on NF dissolution in sweat simulant fluids. We investigated the dissolution of zinc oxide and silicon dioxide NFs in different artificial sweat fluids, demonstrating the importance of using physiologically relevant conditions for dermal exposure. All existing and generated data informed the formulation of the grouping hypotheses, the IATAs, and the design of the TTS. It is expected that the presented IATAs will accelerate the NF risk assessment for dermal toxicity via the application of read-across.
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Affiliation(s)
- Luisana Di Cristo
- D3 PharmaChemistry, Nanoregulatory Group, Italian Institute of Technology, Genova, Italy
| | - Gemma Janer
- LEITAT Technological Center, Barcelona, Spain
| | - Susan Dekkers
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | | | - Anna Giusti
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Johannes G Keller
- BASF SE, Dept. Material Physics and Dept of Experimental Toxicology & Ecology, Ludwigshafen, Germany
| | - Wendel Wohlleben
- BASF SE, Dept. Material Physics and Dept of Experimental Toxicology & Ecology, Ludwigshafen, Germany
| | - Hedwig Braakhuis
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Lan Ma-Hock
- BASF SE, Dept. Material Physics and Dept of Experimental Toxicology & Ecology, Ludwigshafen, Germany
| | - Agnes G Oomen
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Andrea Haase
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Vicki Stone
- Nano Safety Research Group, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - Fiona Murphy
- Nano Safety Research Group, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - Helinor J Johnston
- Nano Safety Research Group, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - Stefania Sabella
- D3 PharmaChemistry, Nanoregulatory Group, Italian Institute of Technology, Genova, Italy
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22
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Jeliazkova N, Ma-Hock L, Janer G, Stratmann H, Wohlleben W. Possibilities to group nanomaterials across different substances - A case study on organic pigments. NanoImpact 2022; 26:100391. [PMID: 35560297 DOI: 10.1016/j.impact.2022.100391] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 02/01/2022] [Accepted: 02/02/2022] [Indexed: 06/15/2023]
Abstract
Grouping concepts to reduce the testing of NFs have been developed for regulatory purposes for different forms of the same substance. Here we explore possibilities to group nanomaterials across different substances for non-regulatory applications, using the example of 16 organic pigments from six chemical classes. Organic pigments are particles consisting of low-molar-mass organic molecules, and rank by tonnage among the most important substances manufactured in nanoform (NF). Tiered testing strategies relevant to the inhalation route included Tier 1 (deposition, dissolution, reactivity, inflammation) and if available Tier 3 data (in vivo). A similarity assessment of the pigment NF data was conducted in a quantitative (Tier 1 and Tier 3 in vivo potency) or qualitative (Tier 3 in vivo effects) manner. We observed that chemical similarity of organic pigments was predictive for their similarity of reactivity and dissolution, but that additional NF descriptors such as surface area or size, modulate the similarity in inflammation or cytotoxicity. We applied the concept of biologically relevant ranges to crop the values of the Tier 1 data matrix before applying similarity algorithms. The Tier 3 assessment by in vivo inhalation confirmed the IATA methodical choices and IATA assessment criteria as consistent and conservative. We suggested limits of acceptable similarity for Tier 1 data and demonstrated their application to support the grouping of some candidate NFs (subsequently confirmed by Tier 3 data). Four candidate NFs exceeded the limits of acceptability for Tier 1 and were escalated from Tier 1 to Tier 3, but were then included in the group, demonstrating the conservative Tier 1 criteria. The resulting group of low-solubility, low-reactivity materials included both NFs and non-NFs of various substances, and could find use for risk management purposes in the occupational handling of pigment powders.
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Affiliation(s)
| | - Lan Ma-Hock
- BASF SE, Dept Experimental Toxicology & Ecology, Ludwigshafen, Germany
| | - Gemma Janer
- LEITAT Technological Center, Barcelona, Spain
| | | | - Wendel Wohlleben
- BASF SE, Dept Experimental Toxicology & Ecology, Ludwigshafen, Germany; BASF SE, Dept. Material Physics, Ludwigshafen, Germany.
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23
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Ag Seleci D, Tsiliki G, Werle K, Elam DA, Okpowe O, Seidel K, Bi X, Westerhoff P, Innes E, Boyles M, Miller M, Giusti A, Murphy F, Haase A, Stone V, Wohlleben W. Determining nanoform similarity via assessment of surface reactivity by abiotic and in vitro assays. NanoImpact 2022; 26:100390. [PMID: 35560290 DOI: 10.1016/j.impact.2022.100390] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 02/01/2022] [Accepted: 02/02/2022] [Indexed: 06/15/2023]
Abstract
Grouping of substances is a method used to streamline hazard and risk assessment. Assessment of similarity provides the scientific evidence needed for formation of groups. This work reports on justification of grouping of nanoforms (NFs) via similarity of their surface reactivity. Four reactivity assays were used for concentration dependent detection of reactive oxygen species (ROS) generated by NFs: abiotic assays FRAS, EPR and DCFH2-DA, as well as the in vitro assay of NRF2/ARE responsive luciferase reporter activation in the HEK293 cell line. Representative materials (CuO, Mn2O3, BaSO4, CeO2 and ZnO) and three case studies of each several NFs of iron oxides, Diketopyrrolopyrroles (DPP)-based organic pigments and silicas were assessed. A novel similarity assessment algorithm was applied to quantify similarities between pairs of NFs, in a four-step workflow on concentration-response curves, individual concentration and response ranges, and finally the representative materials. We found this algorithm to be applicable to all abiotic and in vitro assays that were tested. Justification of grouping must include the increased potency of smaller particles via the scaling of effects with specific surface, and hence quantitative similarity analysis was performed on concentration-response in mass-metrics. CuO and BaSO4 were the most and least reactive representative materials respectively, and all assays found BaSO4/CuO not similar, as confirmed by their different NOAECs of in vivo studies. However, similarity outcomes from different reactivity assays were not always in agreement, highlighting the need to generate data by one assay for the representative materials and the candidate group of NFs. Despite low similarity scores in vitro some pairs of case study NFs can be accepted as sufficiently similar because the in vivo NOAECs are similar, highlighting the conservative assessment by the abiotic assays.
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Affiliation(s)
- Didem Ag Seleci
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | | | - Kai Werle
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Derek A Elam
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Omena Okpowe
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Karsten Seidel
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Xiangyu Bi
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany; School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, USA
| | - Paul Westerhoff
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, USA
| | - Emma Innes
- Institute of Occupational Medicine, Edinburgh, United Kingdom
| | - Matthew Boyles
- Institute of Occupational Medicine, Edinburgh, United Kingdom
| | - Mark Miller
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Anna Giusti
- German Federal Institute for Risk Assessment, Department of Chemical and Product Safety, Berlin, Germany
| | - Fiona Murphy
- NanoSafety Group, Heriot-Watt University, Edinburgh, United Kingdom
| | - Andrea Haase
- German Federal Institute for Risk Assessment, Department of Chemical and Product Safety, Berlin, Germany
| | - Vicki Stone
- NanoSafety Group, Heriot-Watt University, Edinburgh, United Kingdom
| | - Wendel Wohlleben
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany.
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24
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Doak SH, Clift MJD, Costa A, Delmaar C, Gosens I, Halappanavar S, Kelly S, Pejinenburg WJGM, Rothen-Rutishauser B, Schins RPF, Stone V, Tran L, Vijver MG, Vogel U, Wohlleben W, Cassee FR. The Road to Achieving the European Commission's Chemicals Strategy for Nanomaterial Sustainability-A PATROLS Perspective on New Approach Methodologies. Small 2022; 18:e2200231. [PMID: 35324067 DOI: 10.1002/smll.202200231] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/17/2022] [Indexed: 06/14/2023]
Abstract
The European Green Deal outlines ambitions to build a more sustainable, climate neutral, and circular economy by 2050. To achieve this, the European Commission has published the Chemicals Strategy for Sustainability: Towards a Toxic-Free Environment, which provides targets for innovation to better protect human and environmental health, including challenges posed by hazardous chemicals and animal testing. The European project PATROLS (Physiologically Anchored Tools for Realistic nanOmateriaL hazard aSsessment) has addressed multiple aspects of the Chemicals Strategy for Sustainability by establishing a battery of new approach methodologies, including physiologically anchored human and environmental hazard assessment tools to evaluate the safety of engineered nanomaterials. PATROLS has delivered and improved innovative tools to support regulatory decision-making processes. These tools also support the need for reducing regulated vertebrate animal testing; when used at an early stage of the innovation pipeline, the PATROLS tools facilitate the safe and sustainable development of new nano-enabled products before they reach the market.
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Affiliation(s)
- Shareen H Doak
- Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK
| | - Martin J D Clift
- Swansea University Medical School, Singleton Park, Swansea, SA2 8PP, UK
| | - Anna Costa
- Institute of Science and Technology for Ceramics, CNR-ISTEC-National Research Council of Italy, Faenza, Italy
| | - Christiaan Delmaar
- National Institute for Public Health and the Environment Netherlands, PO box 1, Bilthoven, 3720, the Netherlands
| | - Ilse Gosens
- National Institute for Public Health and the Environment Netherlands, PO box 1, Bilthoven, 3720, the Netherlands
| | - Sabina Halappanavar
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, K1A0K9, Canada
| | - Sean Kelly
- Nanotechnology Industries Association, Avenue Tervueren 143, Brussels, 1150, Belgium
| | - Willie J G M Pejinenburg
- National Institute for Public Health and the Environment Netherlands, PO box 1, Bilthoven, 3720, the Netherlands
- Leiden University, PO Box 9518, Leiden, 2300 RA, the Netherlands
| | | | - Roel P F Schins
- IUF-Leibniz Research Institute for Environmental Medicine, Auf'm Hennekamp 50, 40225, Düsseldorf, Germany
| | - Vicki Stone
- School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh, UK
| | - Lang Tran
- Institute of Occupational Medicine (IOM), Edinburgh, Scotland, EH14 4AP, UK
| | - Martina G Vijver
- Leiden University, PO Box 9518, Leiden, 2300 RA, the Netherlands
| | - Ulla Vogel
- National Research Centre for the Working Environment, Copenhagen, DK-2100, Denmark
| | - Wendel Wohlleben
- Advanced Materials Research, BASF SE, 67056, Ludwigshafen, Germany
| | - Flemming R Cassee
- National Institute for Public Health and the Environment Netherlands, PO box 1, Bilthoven, 3720, the Netherlands
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands
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25
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Landsiedel R, Hahn D, Ossig R, Ritz S, Sauer L, Buesen R, Rehm S, Wohlleben W, Groeters S, Strauss V, Sperber S, Wami H, Dobrindt U, Prior K, Harmsen D, van Ravenzwaay B, Schnekenburger J. Gut microbiome and plasma metabolome changes in rats after oral gavage of nanoparticles: sensitive indicators of possible adverse health effects. Part Fibre Toxicol 2022; 19:21. [PMID: 35321750 PMCID: PMC8941749 DOI: 10.1186/s12989-022-00459-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 03/01/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The oral uptake of nanoparticles is an important route of human exposure and requires solid models for hazard assessment. While the systemic availability is generally low, ingestion may not only affect gastrointestinal tissues but also intestinal microbes. The gut microbiota contributes essentially to human health, whereas gut microbial dysbiosis is known to promote several intestinal and extra-intestinal diseases. Gut microbiota-derived metabolites, which are found in the blood stream, serve as key molecular mediators of host metabolism and immunity. RESULTS Gut microbiota and the plasma metabolome were analyzed in male Wistar rats receiving either SiO2 (1000 mg/kg body weight/day) or Ag nanoparticles (100 mg/kg body weight/day) during a 28-day oral gavage study. Comprehensive clinical, histopathological and hematological examinations showed no signs of nanoparticle-induced toxicity. In contrast, the gut microbiota was affected by both nanoparticles, with significant alterations at all analyzed taxonomical levels. Treatments with each of the nanoparticles led to an increased abundance of Prevotellaceae, a family with gut species known to be correlated with intestinal inflammation. Only in Ag nanoparticle-exposed animals, Akkermansia, a genus known for its protective impact on the intestinal barrier was depleted to hardly detectable levels. In SiO2 nanoparticles-treated animals, several genera were significantly reduced, including probiotics such as Enterococcus. From the analysis of 231 plasma metabolites, we found 18 metabolites to be significantly altered in Ag-or SiO2 nanoparticles-treated rats. For most of these metabolites, an association with gut microbiota has been reported previously. Strikingly, both nanoparticle-treatments led to a significant reduction of gut microbiota-derived indole-3-acetic acid in plasma. This ligand of the arylhydrocarbon receptor is critical for regulating immunity, stem cell maintenance, cellular differentiation and xenobiotic-metabolizing enzymes. CONCLUSIONS The combined profiling of intestinal microbiome and plasma metabolome may serve as an early and sensitive indicator of gut microbiome changes induced by orally administered nanoparticles; this will help to recognize potential adverse effects of these changes to the host.
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Affiliation(s)
- Robert Landsiedel
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany.,Institute of Pharmacy, Pharmacology and Toxicology, Freie Universität Berlin, 14195, Berlin, Germany
| | - Daniela Hahn
- Biomedical Technology Center of the Medical Faculty, University of Muenster, Mendelstrasse 17, 48149, Muenster, Germany
| | - Rainer Ossig
- Biomedical Technology Center of the Medical Faculty, University of Muenster, Mendelstrasse 17, 48149, Muenster, Germany
| | - Sabrina Ritz
- Biomedical Technology Center of the Medical Faculty, University of Muenster, Mendelstrasse 17, 48149, Muenster, Germany
| | - Lydia Sauer
- Biomedical Technology Center of the Medical Faculty, University of Muenster, Mendelstrasse 17, 48149, Muenster, Germany
| | - Roland Buesen
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany
| | - Sascha Rehm
- HB Technologies AG, 72076, Tübingen, Germany.,Medical Data Integration Center, University Tuebingen, 72072, Tübingen, Germany
| | | | - Sibylle Groeters
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany
| | - Volker Strauss
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany
| | - Saskia Sperber
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen am Rhein, Germany
| | - Haleluya Wami
- Institute of Hygiene, University of Muenster, 48149, Muenster, Germany
| | - Ulrich Dobrindt
- Institute of Hygiene, University of Muenster, 48149, Muenster, Germany
| | - Karola Prior
- Department of Periodontology and Operative Dentistry, University Hospital Muenster, 48149, Muenster, Germany
| | - Dag Harmsen
- Department of Periodontology and Operative Dentistry, University Hospital Muenster, 48149, Muenster, Germany
| | | | - Juergen Schnekenburger
- Biomedical Technology Center of the Medical Faculty, University of Muenster, Mendelstrasse 17, 48149, Muenster, Germany.
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26
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Boyles M, Murphy F, Mueller W, Wohlleben W, Jacobsen NR, Braakhuis H, Giusti A, Stone V. Development of a standard operating procedure for the DCFH 2-DA acellular assessment of reactive oxygen species produced by nanomaterials. Toxicol Mech Methods 2022; 32:439-452. [PMID: 35086424 DOI: 10.1080/15376516.2022.2029656] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Improved strategies are required for testing nanomaterials (NMs) to make hazard and risk assessment more efficient and sustainable. Including reduced reliance on animal models, without decreasing the level of human health protection. Acellular detection of reactive oxygen species (ROS) may be useful as a screening assay to prioritize NMs of high concern. To improve reliability and reproducibility, and minimize uncertainty, a standard operating procedure (SOP) has been developed for the detection of ROS using the 2',7'-dichlorodihydrofluorescein diacetate (DCFH2-DA) assay. The SOP has undergone an inter- and intra-laboratory comparison, to evaluate robustness, reliability, and reproducibility, using representative materials (ZnO, CuO, Mn2O3, and BaSO4 NMs), and a number of calibration tools to normalize data. The SOP includes an NM positive control (nanoparticle carbon black (NPCB)), a chemical positive control (SIN-1), and a standard curve of fluorescein fluorescence. The interlaboratory comparison demonstrated that arbitrary fluorescence units show high levels of partner variability; however, data normalization improved variability. With statistical analysis, it was shown that the SIN-1 positive control provided an extremely high level of reliability and reproducibility as a positive control and as a normalization tool. The NPCB positive control can be used with a relatively high level of reproducibility, and in terms of the representative materials, the reproducibility CuO induced-effects was better than for Mn2O3. Using this DCFH2-DA acellular assay SOP resulted in a robust intra-laboratory reproduction of ROS measurements from all NMs tested, while effective reproduction across different laboratories was also demonstrated; the effectiveness of attaining reproducibility within the interlaboratory assessment was particle-type-specific.
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Affiliation(s)
| | - Fiona Murphy
- NanoSafety Group, Heriot-Watt University, Edinburgh, UK
| | | | - Wendel Wohlleben
- Department of Material Physics and Department of Experimental Toxicology & Ecology, BASF SE, Ludwigshafen, Germany
| | | | - Hedwig Braakhuis
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Anna Giusti
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Vicki Stone
- NanoSafety Group, Heriot-Watt University, Edinburgh, UK
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27
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Singh D, Marrocco A, Wohlleben W, Park HR, Diwadkar AR, Himes BE, Lu Q, Christiani DC, Demokritou P. Release of particulate matter from nano-enabled building materials (NEBMs) across their lifecycle: Potential occupational health and safety implications. J Hazard Mater 2022; 422:126771. [PMID: 34391975 PMCID: PMC8595827 DOI: 10.1016/j.jhazmat.2021.126771] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 07/20/2021] [Accepted: 07/26/2021] [Indexed: 05/11/2023]
Abstract
The present study investigates potential nanomaterial releases and occupational health risks across the lifecycle of nano-enabled building materials (NEBMs), namely, insulations and coatings. We utilized real-world degradation scenarios of a) sanding (mechanical), b) incineration (thermal), and c) accelerated UV-aging (environmental) followed by incineration. Extensive physicochemical characterization of the released lifecycle particulate matter (LCPM) was performed. The LCPM2.5 aerosol size fraction was used to assess the acute biological, cytotoxic and inflammatory effects on Calu-3 human lung epithelial cells. RNA-Seq analysis of exposed cells was performed to assess potential for systemic disease. Findings indicated that release dynamics and characteristics of LCPM depended on both the NEBM composition and the degradation scenario(s). Incineration emitted a much higher nanoparticle number concentration than sanding (nearly 4 orders of magnitude), which did not change with prior UV-aging. Released nanofillers during sanding were largely part of the matrix fragments, whereas those during incineration were likely physicochemically transformed. The LCPM from incineration showed higher bioactivity and inflammogenicity compared to sanding or sequential UV-aging and incineration, and more so when metallic nanofillers were present (such as Fe2O3). Overall, the study highlights the need for considering real-world exposure and toxicological data across the NEBM lifecycle to perform adequate risk assessments and to ensure workplace health and safety.
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Affiliation(s)
- Dilpreet Singh
- Center for Nanotechnology and Nanotoxicology, Harvard T.H. Chan School of Public Health, Harvard University, 665 Huntington Ave., Boston, MA 02115, USA
| | - Antonella Marrocco
- Center for Nanotechnology and Nanotoxicology, Harvard T.H. Chan School of Public Health, Harvard University, 665 Huntington Ave., Boston, MA 02115, USA
| | | | - Hae-Ryung Park
- Department of Environmental Medicine, School of Medicine and Dentistry, University of Rochester, NY 14642, USA
| | - Avantika R Diwadkar
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Blanca E Himes
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Quan Lu
- Molecular and Integrative Physiological Sciences, Department of Environmental Health, T.H. Chan School of Public Health, Harvard University, 665 Huntington Ave., Boston, MA 02115, USA
| | - David C Christiani
- Center for Nanotechnology and Nanotoxicology, Harvard T.H. Chan School of Public Health, Harvard University, 665 Huntington Ave., Boston, MA 02115, USA
| | - Philip Demokritou
- Center for Nanotechnology and Nanotoxicology, Harvard T.H. Chan School of Public Health, Harvard University, 665 Huntington Ave., Boston, MA 02115, USA.
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28
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Loosli F, Rasmussen K, Rauscher H, Cross RK, Bossa N, Peijnenburg W, Arts J, Matzke M, Svendsen C, Spurgeon D, Clausen PA, Ruggiero E, Wohlleben W, von der Kammer F. Refinement of the selection of physicochemical properties for grouping and read-across of nanoforms. NanoImpact 2022; 25:100375. [PMID: 35559881 DOI: 10.1016/j.impact.2021.100375] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/24/2021] [Accepted: 12/08/2021] [Indexed: 06/15/2023]
Abstract
Before placing a new nanoform (NF) on the market, its potential adverse effects must be evaluated. This may e.g. be done via hazard and risk assessment. Grouping and read-across of NFs is a possible strategy to reduce resource consumption, maximising the use of existing data for assessment of NFs. The GRACIOUS project provides a framework in which possible grouping and read-across for NFs is mainly based on an evaluation of their similarity. The impact of NFs on human health and the environment depends strongly on the concentration of the NF and its physicochemical properties, such as chemical composition, size distribution, shape, etc. Hence, knowledge of the most relevant physicochemical properties is essential information for comparing similarity. The presented work aims to refine existing proposals for sets of descriptors (descriptor array) that are needed to describe distinct NFs of a material to identify the most relevant ones for grouping and read-across. The selection criteria for refining this descriptor array are explained and demonstrated. Relevant protocols and methods are proposed for each physicochemical property. The required and achievable measurement accuracies of the refined descriptor array are reviewed, as this information is necessary for similarity assessment of NFs based on individual physicochemical properties.
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Affiliation(s)
- Frédéric Loosli
- Environmental Geosciences, Centre for Microbiology and Environmental Systems Science, University of Vienna, Wien, Austria.
| | | | - Hubert Rauscher
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Richard K Cross
- UK Centre for Ecology and Hydrology, Pollution, Wallingford, Oxfordshire, United Kingdom
| | - Nathan Bossa
- Leitat Technological Center, 08225 Terrassa, Barcelona, Spain
| | - Willie Peijnenburg
- National Institute of Public Health and the Environment (RIVM), Center for Safety of Substances and Products, Bilthoven, the Netherlands; Leiden University, Institute of Environmental Sciences (CML), P.O. Box 9518, 2300 RA Leiden, the Netherlands
| | - Josje Arts
- Nouryon Chemicals BV, Velperweg 76, 6824 BM Arnhem, the Netherlands
| | - Marianne Matzke
- UK Centre for Ecology and Hydrology, Pollution, Wallingford, Oxfordshire, United Kingdom
| | - Claus Svendsen
- UK Centre for Ecology and Hydrology, Pollution, Wallingford, Oxfordshire, United Kingdom
| | - David Spurgeon
- UK Centre for Ecology and Hydrology, Pollution, Wallingford, Oxfordshire, United Kingdom
| | - Per Axel Clausen
- The National Research Centre for the Working Environment (NFA), Lersø Parkallé 105, 2100 Copenhagen East, Denmark
| | - Emmanuel Ruggiero
- BASF SE, Dept. of Material Physics, Dept. of Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany
| | - Wendel Wohlleben
- BASF SE, Dept. of Material Physics, Dept. of Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany
| | - Frank von der Kammer
- Environmental Geosciences, Centre for Microbiology and Environmental Systems Science, University of Vienna, Wien, Austria
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29
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Tsiliki G, Ag Seleci D, Zabeo A, Basei G, Hristozov D, Jeliazkova N, Boyles M, Murphy F, Peijnenburg W, Wohlleben W, Stone V. Bayesian based similarity assessment of nanomaterials to inform grouping. NanoImpact 2022; 25:100389. [PMID: 35559895 DOI: 10.1016/j.impact.2022.100389] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 12/29/2021] [Accepted: 02/02/2022] [Indexed: 06/15/2023]
Abstract
Nanoforms can be manufactured in plenty of variants by differing their physicochemical properties and toxicokinetic behaviour which can affect their hazard potential. To avoid testing of each single nanomaterial and nanoform variation and subsequently save resources, grouping and read-across strategies are used to estimate groups of substances, based on carefully selected evidence, that could potentially have similar human health and environmental hazard impact. A novel computational similarity method is presented aiming to compare dose-response curves and identify sets of similar nanoforms. The suggested method estimates the statistical model that best fits the data by leveraging pairwise Bayes Factor analysis to compare pairs of curves and evaluate whether each of the nanoforms is sufficiently similar to all other nanoforms. Pairwise comparisons to benchmark materials are used to define threshold similarity values and set the criteria for identifying groups of nanoforms with comparatively similar toxicity. Applications to use case data are shown to demonstrate that the method can support grouping hypotheses linked to a certain hazard endpoint and route of exposure.
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Affiliation(s)
- Georgia Tsiliki
- Institute for the Management of Information Systems, Athena Research Center, Marousi, Greece.
| | - Didem Ag Seleci
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | | | | | | | | | - Matthew Boyles
- Institute of Occupational Medicine, Edinburgh, United Kingdom
| | - Fiona Murphy
- NanoSafety Group, Heriot-Watt University, Edinburgh, United Kingdom
| | - Willie Peijnenburg
- National Institute of Public Health and the Environment (RIVM), Center for Safety of Substances and Products, Bilthoven, the Netherlands; Leiden University, Institute of Environmental Sciences (CML), Leiden, the Netherlands
| | - Wendel Wohlleben
- Advanced Materials Research, Dept. of Material Physics and Analytics and Dept. of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Vicki Stone
- NanoSafety Group, Heriot-Watt University, Edinburgh, United Kingdom
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30
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Ruggiero E, Santizo KY, Persson M, Delpivo C, Wohlleben W. Food contact of paper and plastic products containing SiO 2, Cu-Phthalocyanine, Fe 2O 3, CaCO 3: Ranking factors that control the similarity of form and rate of release. NanoImpact 2022; 25:100372. [PMID: 35559878 DOI: 10.1016/j.impact.2021.100372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/24/2021] [Accepted: 11/30/2021] [Indexed: 06/15/2023]
Abstract
The paper industry is an important sector annually consuming kilotons of nanoforms and non-nanoforms of fillers and pigments. Fillers accelerate the rate of drying (less energy needed) and product cost (increasing the load of low-cost fillers). The plastic industry is another use sector, where coloristic pigments can be in nanoform, and many food containers are made of plastic. Use of paper to wrap both wet and dry food is consumer practice, but not always intended by producers. Here we compare the release behavior of different nano-enabled products (NEPs) by changing a) nanoform (NF) characteristics, b) NF load, c) the nano-enabled product (NEP) matrix, and d) food simulants. The ranking of these factors enables an assessment of food contact by concepts of analogy, specifically via the similarities of the rate and form of release in food during contact. Three types of matrices were used: Paper, plastic ((Polylactic Acid (PLA), Polyamide (PA6), and Polyurethane (PU)), and a paint formulation. Two nanoforms each of SiO2, Fe2O3, Cu-Phthalocyanine were incorporated, additionally to the conventional form of CaCO3 that is always contained in paper to reduce cellulose consumption. Tests were guided by the European Regulation EC 1935/2004 and EU 10/2011. No evidence of particle release was observed: the qualitative similarity (the form of release) was high regarding the food contact of all NEPs with embedded NFs. Quantitative similarity of releases depended primarily on the NEP matrix, as this controls the penetration of the simulant fluid into the NEP. The solubility of the NF and impurities in the simulant fluid was the second decisive factor, as dissolution of the NF inside the NEP is the main mechanism of release. This led to complete removal of CaCO3 in acidic medium, whereas Fe and Si signals remained in the paper, consistent with the low release rates in an ionic form. In our set of 16 NEPs, only one NEP showed a dependence on the REACH NF descriptors (substance, size, shape, surface treatment, crystallinity, impurities), specifically attributed to differences in soluble impurities, whereas for all others the substance of the nanoform was sufficient to predict a similarity of food contact release, without influences of size, shape, surface treatment and crystallinity.
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Affiliation(s)
- Emmanuel Ruggiero
- BASF SE, Dept. Material Physics, 67056 Ludwigshafen, Germany; Avient, Milano, Italy
| | - Katherine Y Santizo
- BASF SE, Dept. Material Physics, 67056 Ludwigshafen, Germany; Virginia Tech, Blacksburg, VA USA
| | - Michael Persson
- Nouryon Pulp and Performance Chemicals AB, S-445 80 Bohus, Sweden; Chalmers Industriteknik Sven Hultins Plats 1, S-412 58 Gothenburg, Sweden
| | - Camilla Delpivo
- LEITAT Technological Center, C/Pallars 179-185, 08005 Barcelona, Spain
| | - Wendel Wohlleben
- BASF SE, Dept. Material Physics, 67056 Ludwigshafen, Germany; BASF SE, Dept. Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany.
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31
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Jeliazkova N, Bleeker E, Cross R, Haase A, Janer G, Peijnenburg W, Pink M, Rauscher H, Svendsen C, Tsiliki G, Zabeo A, Hristozov D, Stone V, Wohlleben W. How can we justify grouping of nanoforms for hazard assessment? Concepts and tools to quantify similarity. NanoImpact 2022; 25:100366. [PMID: 35559874 DOI: 10.1016/j.impact.2021.100366] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 10/15/2021] [Accepted: 11/12/2021] [Indexed: 06/15/2023]
Abstract
The risk of each nanoform (NF) of the same substance cannot be assumed to be the same, as they may vary in their physicochemical characteristics, exposure and hazard. However, neither can we justify a need for more animal testing and resources to test every NF individually. To reduce the need to test all NFs, (regulatory) information requirements may be fulfilled by grouping approaches. For such grouping to be acceptable, it is important to demonstrate similarities in physicochemical properties, toxicokinetic behaviour, and (eco)toxicological behaviour. The GRACIOUS Framework supports the grouping of NFs, by identifying suitable grouping hypotheses that describe the key similarities between different NFs. The Framework then supports the user to gather the evidence required to test these hypotheses and to subsequently assess the similarity of the NFs within the proposed group. The evidence needed to support a hypothesis is gathered by an Integrated Approach to Testing and Assessment (IATA), designed as decision trees constructed of decision nodes. Each decision node asks the questions and provides the methods needed to obtain the most relevant information. This White paper outlines existing and novel methods to assess similarity of the data generated for each decision node, either via a pairwise analysis conducted property-by-property, or by assessing multiple decision nodes simultaneously via a multidimensional analysis. For the pairwise comparison conducted property-by-property we included in this White paper: The x-fold, Bayesian and Arsinh-OWA distance algorithms performed comparably in the scoring of similarity between NF pairs. The Euclidean distance was also useful, but only with proper data transformation. The x-fold method does not standardize data, and thus produces skewed histograms, but has the advantage that it can be implemented without programming knowhow. A range of multidimensional evaluations, using for example dendrogram clustering approaches, were also investigated. Multidimensional distance metrics were demonstrated to be difficult to use in a regulatory context, but from a scientific perspective were found to offer unexpected insights into the overall similarity of very different materials. In conclusion, for regulatory purposes, a property-by-property evaluation of the data matrix is recommended to substantiate grouping, while the multidimensional approaches are considered to be tools of discovery rather than regulatory methods.
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Affiliation(s)
| | - Eric Bleeker
- National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Richard Cross
- UKRI Centre for Ecology and Hydrology, MacLean Building, Benson Lane, Wallingford OX10 8BB, UK
| | - Andrea Haase
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Gemma Janer
- LEITAT Technological Center, Barcelona, Spain
| | - Willie Peijnenburg
- National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands; Institute of Environmental Sciences (CML), Leiden University, Leiden, the Netherlands
| | - Mario Pink
- German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin, Germany
| | - Hubert Rauscher
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Claus Svendsen
- UKRI Centre for Ecology and Hydrology, MacLean Building, Benson Lane, Wallingford OX10 8BB, UK
| | - Georgia Tsiliki
- Athena-Research and Innovation Center in Information, Communication and Knowledge Technologies, Marousi, Greece
| | | | | | - Vicki Stone
- NanoSafety Research Group, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, UK
| | - Wendel Wohlleben
- BASF SE, Dept. Material Physics and Dept Experimental Toxicology & Ecology, Ludwigshafen, Germany.
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Wall J, Seleci DA, Schworm F, Neuberger R, Link M, Hufnagel M, Schumacher P, Schulz F, Heinrich U, Wohlleben W, Hartwig A. Comparison of Metal-Based Nanoparticles and Nanowires: Solubility, Reactivity, Bioavailability and Cellular Toxicity. Nanomaterials (Basel) 2021; 12:nano12010147. [PMID: 35010097 PMCID: PMC8746854 DOI: 10.3390/nano12010147] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/21/2021] [Accepted: 12/28/2021] [Indexed: 11/16/2022]
Abstract
While the toxicity of metal-based nanoparticles (NP) has been investigated in an increasing number of studies, little is known about metal-based fibrous materials, so-called nanowires (NWs). Within the present study, the physico-chemical properties of particulate and fibrous nanomaterials based on Cu, CuO, Ni, and Ag as well as TiO2 and CeO2 NP were characterized and compared with respect to abiotic metal ion release in different physiologically relevant media as well as acellular reactivity. While none of the materials was soluble at neutral pH in artificial alveolar fluid (AAF), Cu, CuO, and Ni-based materials displayed distinct dissolution under the acidic conditions found in artificial lysosomal fluids (ALF and PSF). Subsequently, four different cell lines were applied to compare cytotoxicity as well as intracellular metal ion release in the cytoplasm and nucleus. Both cytotoxicity and bioavailability reflected the acellular dissolution rates in physiological lysosomal media (pH 4.5); only Ag-based materials showed no or very low acellular solubility, but pronounced intracellular bioavailability and cytotoxicity, leading to particularly high concentrations in the nucleus. In conclusion, in spite of some quantitative differences, the intracellular bioavailability as well as toxicity is mostly driven by the respective metal and is less modulated by the shape of the respective NP or NW.
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Affiliation(s)
- Johanna Wall
- Department of Food Chemistry and Toxicology, Faculty of Chemistry and Biosciences, Institute of Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany; (J.W.); (F.S.); (R.N.); (M.L.); (M.H.); (P.S.)
| | | | - Feranika Schworm
- Department of Food Chemistry and Toxicology, Faculty of Chemistry and Biosciences, Institute of Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany; (J.W.); (F.S.); (R.N.); (M.L.); (M.H.); (P.S.)
| | - Ronja Neuberger
- Department of Food Chemistry and Toxicology, Faculty of Chemistry and Biosciences, Institute of Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany; (J.W.); (F.S.); (R.N.); (M.L.); (M.H.); (P.S.)
| | - Martin Link
- Department of Food Chemistry and Toxicology, Faculty of Chemistry and Biosciences, Institute of Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany; (J.W.); (F.S.); (R.N.); (M.L.); (M.H.); (P.S.)
| | - Matthias Hufnagel
- Department of Food Chemistry and Toxicology, Faculty of Chemistry and Biosciences, Institute of Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany; (J.W.); (F.S.); (R.N.); (M.L.); (M.H.); (P.S.)
| | - Paul Schumacher
- Department of Food Chemistry and Toxicology, Faculty of Chemistry and Biosciences, Institute of Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany; (J.W.); (F.S.); (R.N.); (M.L.); (M.H.); (P.S.)
| | | | | | | | - Andrea Hartwig
- Department of Food Chemistry and Toxicology, Faculty of Chemistry and Biosciences, Institute of Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany; (J.W.); (F.S.); (R.N.); (M.L.); (M.H.); (P.S.)
- Correspondence:
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Karkossa I, Bannuscher A, Hellack B, Wohlleben W, Laloy J, Stan MS, Dinischiotu A, Wiemann M, Luch A, Haase A, von Bergen M, Schubert K. Nanomaterials induce different levels of oxidative stress, depending on the used model system: Comparison of in vitro and in vivo effects. Sci Total Environ 2021; 801:149538. [PMID: 34428663 DOI: 10.1016/j.scitotenv.2021.149538] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
The immense diversity and constant development of nanomaterials (NMs) increase the need for a facilitated risk assessment, which requires knowledge of the modes of action (MoAs) of NMs. This necessitates a comprehensive data basis, which can be obtained using omics. Furthermore, the establishment of suitable in vitro test systems is essential to follow the 3R concept and to cope with the high number of NMs. In the present study, we aimed to compare NM effects in vitro and in vivo using a multi-omics approach. We applied an integrated data analysis strategy based on proteomics and metabolomics to four silica NMs and one titanium dioxide-based NM. For the in vitro investigations, rat alveolar epithelial cells (RLE-6TN) and rat alveolar macrophages (NR8383) were treated with different doses of NMs, and the results were compared with the effects on rat lungs after short-term inhalations and instillations. Since reactive oxygen species (ROS) production has been described as a critical biological effect of NMs, we focused on different levels of oxidative stress. Thus, we found opposite changes in proteins and metabolites related to the production of reduced glutathione in alveolar epithelial cells and alveolar macrophages, demonstrating that the MoAs of NMs depend on the model system used. Interestingly, in vivo, pathways related to inflammation were more affected than oxidative stress responses. Hence, the assignment of the observed effects to levels of oxidative stress was also different in vitro and in vivo. However, the overall classification of "active" and "passive" NMs was consistent in vitro and in vivo, suggesting that both cell lines tested are suitable for the assessment of NM toxicity. In summary, the results presented here highlight the need to carefully review model systems to decipher the extent to which they can replace in vivo assays.
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Affiliation(s)
- Isabel Karkossa
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Anne Bannuscher
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany; Adolphe Merkle Institute (AMI), University of Fribourg, Fribourg, Switzerland
| | - Bryan Hellack
- Institute of Energy and Environmental Technology (IUTA) e.V., Duisburg, Germany; German Environment Agency (UBA), Dessau, Germany
| | | | - Julie Laloy
- Department of Pharmacy, Namur Nanosafety Centre, University of Namur, Namur, Belgium
| | - Miruna S Stan
- Department of Biochemistry and Molecular Biology, University of Bucharest, Bucharest, Romania
| | - Anca Dinischiotu
- Department of Biochemistry and Molecular Biology, University of Bucharest, Bucharest, Romania
| | - Martin Wiemann
- IBE R&D Institute for Lung Health gGmbH, Münster, Germany
| | - Andreas Luch
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Andrea Haase
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Martin von Bergen
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany; Institute of Biochemistry, Leipzig University, Leipzig, Germany
| | - Kristin Schubert
- Department of Molecular Systems Biology, Helmholtz-Centre for Environmental Research - UFZ, Leipzig, Germany.
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Janer G, Ag-Seleci D, Sergent JA, Landsiedel R, Wohlleben W. Creating sets of similar nanoforms with the ECETOC NanoApp: real-life case studies. Nanotoxicology 2021; 15:1016-1034. [PMID: 34242099 DOI: 10.1080/17435390.2021.1946186] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The ECETOC NanoApp was developed to support industry in the registration of sets of nanoforms, as well as regulators in the evaluation of these registration dossiers. The ECETOC NanoApp uses a systematic approach to create and justify sets of similar nanoforms, following the ECHA guidance in a transparent and evidence-based manner. The rational and decision rules behind the ECETOC NanoApp are described in detail in "Janer, G., R. Landsiedel, and W. Wohlleben. 2021. [Rationale and Decision Rules Behind the ECETOC NanoApp to Support Registration of Sets of Similar Nanoforms within REACH. Nanotoxicology 15 (2): 145-122. https://doi.org/10.1080/17435390.2020.1842933]". The decision criteria apply to human health and environmental hazards and risks. Here, we focus mostly on human health hazards; the decision rules are applied to a series of case studies, each consisting of real nanoforms: two barium sulfate nanoforms, four colloidal silica nanoforms, eight ceria nanoforms, and four copper phthalocyanine nanoforms. For each of them, we show step by step how the ECETOC NanoApp rules are applied. The cases include nanoforms that are justified as members of the same set of similar nanoforms based on sufficient similarity of their intrinsic properties (Tier 1). They also include other nanoforms with a relatively high (but insufficient) similarity of intrinsic properties; their similarity could be justified by functional properties (Tier 2). The case studies also include nanoforms that are concluded not to belong to the same set of similar nanoforms. These outcomes of the NanoApp were overall consistent (sometimes conservative) with available in vivo data. We also noted that datasets for various nanoforms were limited and use of the NanoApp may require the generation of data relevant to the decision criteria.
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Affiliation(s)
- Gemma Janer
- Leitat Technological Center, Barcelona, Spain
| | - Didem Ag-Seleci
- BASF SE, Department Material Physics and Analytics, Ludwigshafen am Rhein, Germany
| | | | - Robert Landsiedel
- BASF SE, Department Experimental Toxicology and Ecology, Ludwigshafen am Rhein, Germany
| | - Wendel Wohlleben
- BASF SE, Department Material Physics and Analytics, Ludwigshafen am Rhein, Germany.,BASF SE, Department Experimental Toxicology and Ecology, Ludwigshafen am Rhein, Germany
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35
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Sauer UG, Werle K, Waindok H, Hirth S, Hachmöller O, Wohlleben W. Reply to the Comment on Critical Choices in Predicting Stone Wool Biodurability: Lysosomal Fluid Compositions and Binder Effects. Chem Res Toxicol 2021; 34:1697-1698. [PMID: 34236839 DOI: 10.1021/acs.chemrestox.1c00215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ursula G Sauer
- Scientific Consultancy - Animal Welfare, 85579 Neubiberg, Germany
| | - Kai Werle
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Hubert Waindok
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Sabine Hirth
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Oliver Hachmöller
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Wendel Wohlleben
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
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36
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Stratmann H, Wohlleben W, Wiemann M, Vennemann A, End N, Veith U, Ma-Hock L, Landsiedel R. Classes of organic pigments meet tentative PSLT criteria and lack toxicity in short-term inhalation studies. Regul Toxicol Pharmacol 2021; 124:104988. [PMID: 34224799 DOI: 10.1016/j.yrtph.2021.104988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 10/21/2022]
Abstract
Here, we present a non-animal testing battery to identify PSLT (poorly soluble, low toxicity) substances based on their solubility in phagolysosomal lung fluid simulant, surface reactivity and effects on alveolar macrophages in vitro. This is exemplified by eleven organic pigments belonging to five chemical classes that cover a significant share of the European market. Three of the pigments were tested as both, nanoform and non-nanoform. The results obtained in this integrated non-animal testing battery qualified two pigments as non PSLT, one pigment as poorly soluble and eight pigments as poorly soluble and low toxicity in vitro. The low toxic potency of the eight PSLT and the one poorly soluble pigment was corroborated by short-term inhalation studies with rats. These pigments did not elicit apparent toxic effects at 10 mg/m3 (systemic and in the respiratory tract). One of the pigments, Diarylide Pigment Yellow 83 transparent, however, caused minimal infiltration of neutrophils; hence its low toxicity is ambiguous and needs further verification or falsification. The present test battery provides an opportunity to identify PSLT-properties of test substances to prioritise particles for further development. Thus, it can help to reduce animal testing and steer product development towards safe applications.
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Affiliation(s)
- Heidi Stratmann
- Department of Product Safety, BASF Schweiz AG, Basel, Switzerland.
| | - Wendel Wohlleben
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056, Ludwigshafen, Germany.
| | - Martin Wiemann
- IBE R&D Institute for Lung Health GmbH, 48149, Münster, Germany.
| | - Antje Vennemann
- IBE R&D Institute for Lung Health GmbH, 48149, Münster, Germany.
| | - Nicole End
- Department of Product Stewardship, BASF Colors & Effects Switzerland AG, Basel, Switzerland.
| | - Ulrich Veith
- Department of Product Stewardship, BASF Colors & Effects Switzerland AG, Basel, Switzerland.
| | - Lan Ma-Hock
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056, Ludwigshafen, Germany.
| | - Robert Landsiedel
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056, Ludwigshafen, Germany.
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37
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Keller JG, Persson M, Müller P, Ma-Hock L, Werle K, Arts J, Landsiedel R, Wohlleben W. Variation in dissolution behavior among different nanoforms and its implication for grouping approaches in inhalation toxicity. NanoImpact 2021; 23:100341. [PMID: 35559842 DOI: 10.1016/j.impact.2021.100341] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 06/17/2021] [Accepted: 07/06/2021] [Indexed: 06/15/2023]
Abstract
Different nanoforms (NF) of the same substance each need to be registered under REACH, but similarities in physiological interaction -among them biodissolution- can justify read-across within a group of NFs, thereby reducing the need to perform animal studies. Here we focused on the endpoint of inhalation toxicity and explored how differences in physical parameters of 17 NFs of silica, and organic and inorganic pigments impact dissolution rates, half-times, and transformation under both pH 7.4 lung lining conditions and pH 4.5 lysosomal conditions. We benchmarked our observations against well-known TiO2, BaSO4 and ZnO nanomaterials, representing very slow, partial and quick dissolution respectively. By automated image evaluation, structural transformations were observed for dissolution rates in the order of 0.1 to 10 ng/cm2/h, but did not provide additional decision criteria on the similarity of NFs. Dissolution half-times spanned nearly five orders of magnitude, mostly dictated by the substance and simulant fluid, but modulated up to ten-fold by the subtle differences between NFs. Physiological time scales and benchmark materials help to frame the biologically relevant range, proposed as 1 h to 1 y. NFs of ZnO, Ag, SiO2, BaSO4 were in this range. We proposed numerical rules of pairwise similarity within a group, of which the worst case NF would be further assessed by in vivo inhalation studies. These rules divided the colloidal silica NFs into two separate candidate groups, one with Al-doping, one without. Shape or silane surface treatment were less important. The dissolution halftimes of many organic and inorganic pigment NFs were longer than the biologically relevant range, such that dissolution behavior is not an obstacle for their groupings.
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Affiliation(s)
- Johannes G Keller
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056 Ludwigshafen, Germany.
| | - Michael Persson
- Nouryon Pulp and Performance Chemicals AB, S-445 80 Bohus, Sweden.
| | - Philipp Müller
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056 Ludwigshafen, Germany.
| | - Lan Ma-Hock
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056 Ludwigshafen, Germany.
| | - Kai Werle
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056 Ludwigshafen, Germany.
| | - Josje Arts
- Nouryon Pulp and Performance Chemicals AB, S-445 80 Bohus, Sweden.
| | - Robert Landsiedel
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056 Ludwigshafen, Germany.
| | - Wendel Wohlleben
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics, 67056 Ludwigshafen, Germany.
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Keller JG, Wiemann M, Gröters S, Werle K, Vennemann A, Landsiedel R, Wohlleben W. Aerogels are not regulated as nanomaterials, but can be assessed by tiered testing and grouping strategies for nanomaterials. Nanoscale Adv 2021; 3:3881-3893. [PMID: 36133012 PMCID: PMC9419173 DOI: 10.1039/d1na00044f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 05/16/2021] [Indexed: 06/16/2023]
Abstract
Aerogels contribute to an increasing number of novel applications due to many unique properties, such as high porosity and low density. They outperform most other insulation materials, and some are also useful as carriers in food or pharma applications. Aerogels are not nanomaterials by the REACH definition but retain properties of nanoscale structures. Here we applied a testing strategy in three tiers. In Tier 1, we examined a panel of 19 aerogels (functionalized chitosan, alginate, pyrolyzed carbon, silicate, cellulose, polyurethane) for their biosolubility, and oxidative potential. Biosolubility was very limited except for some alginate and silicate aerogels. Oxidative potential, as by the ferric reduction ability of human serum (FRAS), was very low except for one chitosan and pyrolyzed carbon, both of which were <10% of the positive control Mn2O3. Five aerogels were further subjected to the Tier 2 alveolar macrophage assay, which revealed no in vitro cytotoxicity, except for silicate and polyurethane that induced increases in tumor necrosis factor α. Insufficiently similar aerogels were excluded from a candidate group, and a worst case identified. In the Tier 3 in vivo instillation, polyurethane (0.3 to 2.4 mg) elicited dose-dependent but reversible enzyme changes in lung lavage fluid on day 3, but no significant inflammatory effects. Overall, the results show a very low inherent toxicity of aerogels and support a categorization based on similarities in Tier 1 and Tier 2. This exemplifies how nanosafety concepts and methods developed on particles can be applied to specific concerns on advanced materials that contain or release nanostructures.
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Affiliation(s)
- Johannes G Keller
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics 67056 Ludwigshafen Germany
| | - Martin Wiemann
- IBE R&D Institute for Lung Health, gGmbH Münster Germany
| | - Sibylle Gröters
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics 67056 Ludwigshafen Germany
| | - Kai Werle
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics 67056 Ludwigshafen Germany
| | | | - Robert Landsiedel
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics 67056 Ludwigshafen Germany
| | - Wendel Wohlleben
- BASF SE, Dept. Experimental Toxicology and Ecology, Dept. Material Physics 67056 Ludwigshafen Germany
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Llewellyn SV, Conway GE, Zanoni I, Jørgensen AK, Shah UK, Seleci DA, Keller JG, Kim JW, Wohlleben W, Jensen KA, Costa A, Jenkins GJS, Clift MJD, Doak SH. Understanding the impact of more realistic low-dose, prolonged engineered nanomaterial exposure on genotoxicity using 3D models of the human liver. J Nanobiotechnology 2021; 19:193. [PMID: 34183029 PMCID: PMC8240362 DOI: 10.1186/s12951-021-00938-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/13/2021] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND With the continued integration of engineered nanomaterials (ENMs) into everyday applications, it is important to understand their potential for inducing adverse human health effects. However, standard in vitro hazard characterisation approaches suffer limitations for evaluating ENM and so it is imperative to determine these potential hazards under more physiologically relevant and realistic exposure scenarios in target organ systems, to minimise the necessity for in vivo testing. The aim of this study was to determine if acute (24 h) and prolonged (120 h) exposures to five ENMs (TiO2, ZnO, Ag, BaSO4 and CeO2) would have a significantly different toxicological outcome (cytotoxicity, (pro-)inflammatory and genotoxic response) upon 3D human HepG2 liver spheroids. In addition, this study evaluated whether a more realistic, prolonged fractionated and repeated ENM dosing regime induces a significantly different toxicity outcome in liver spheroids as compared to a single, bolus prolonged exposure. RESULTS Whilst it was found that the five ENMs did not impede liver functionality (e.g. albumin and urea production), induce cytotoxicity or an IL-8 (pro-)inflammatory response, all were found to cause significant genotoxicity following acute exposure. Most statistically significant genotoxic responses were not dose-dependent, with the exception of TiO2. Interestingly, the DNA damage effects observed following acute exposures, were not mirrored in the prolonged exposures, where only 0.2-5.0 µg/mL of ZnO ENMs were found to elicit significant (p ≤ 0.05) genotoxicity. When fractionated, repeated exposure regimes were performed with the test ENMs, no significant (p ≥ 0.05) difference was observed when compared to the single, bolus exposure regime. There was < 5.0% cytotoxicity observed across all exposures, and the mean difference in IL-8 cytokine release and genotoxicity between exposure regimes was 3.425 pg/mL and 0.181%, respectively. CONCLUSION In conclusion, whilst there was no difference between a single, bolus or fractionated, repeated ENM prolonged exposure regimes upon the toxicological output of 3D HepG2 liver spheroids, there was a difference between acute and prolonged exposures. This study highlights the importance of evaluating more realistic ENM exposures, thereby providing a future in vitro approach to better support ENM hazard assessment in a routine and easily accessible manner.
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Affiliation(s)
- Samantha V Llewellyn
- In Vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
| | - Gillian E Conway
- In Vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
| | - Ilaria Zanoni
- Institute of Science and Technology for Ceramics, CNR-ISTEC-National Research Council of Italy, Faenza, Italy
| | - Amalie Kofoed Jørgensen
- National Research Centre for the Working Environment (NRCWE), Lersø Parkallé 105, 2100, Copenhagen, Denmark
| | - Ume-Kulsoom Shah
- In Vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
| | - Didem Ag Seleci
- Advanced Materials Research, Department of Material Physics and Analytics, BASF SE, 67056, Ludwigshafen, Germany.,Advanced Materials Research, Department of Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen, Germany
| | - Johannes G Keller
- Advanced Materials Research, Department of Material Physics and Analytics, BASF SE, 67056, Ludwigshafen, Germany.,Advanced Materials Research, Department of Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen, Germany
| | - Jeong Won Kim
- Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Daejeon, 34113, Korea
| | - Wendel Wohlleben
- Advanced Materials Research, Department of Material Physics and Analytics, BASF SE, 67056, Ludwigshafen, Germany.,Advanced Materials Research, Department of Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen, Germany
| | - Keld Alstrup Jensen
- National Research Centre for the Working Environment (NRCWE), Lersø Parkallé 105, 2100, Copenhagen, Denmark
| | - Anna Costa
- Institute of Science and Technology for Ceramics, CNR-ISTEC-National Research Council of Italy, Faenza, Italy
| | - Gareth J S Jenkins
- In Vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
| | - Martin J D Clift
- In Vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
| | - Shareen H Doak
- In Vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, SA2 8PP, UK.
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Yokel RA, Wohlleben W, Keller JG, Hancock ML, Unrine JM, Butterfield DA, Grulke EA. The preparation temperature influences the physicochemical nature and activity of nanoceria. Beilstein J Nanotechnol 2021; 12:525-540. [PMID: 34136328 PMCID: PMC8182686 DOI: 10.3762/bjnano.12.43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 05/23/2021] [Indexed: 06/12/2023]
Abstract
Cerium oxide nanoparticles, so-called nanoceria, are engineered nanomaterials prepared by many methods that result in products with varying physicochemical properties and applications. Those used industrially are often calcined, an example is NM-212. Other nanoceria have beneficial pharmaceutical properties and are often prepared by solvothermal synthesis. Solvothermally synthesized nanoceria dissolve in acidic environments, accelerated by carboxylic acids. NM-212 dissolution has been reported to be minimal. To gain insight into the role of high-temperature exposure on nanoceria dissolution, product susceptibility to carboxylic acid-accelerated dissolution, and its effect on biological and catalytic properties of nanoceria, the dissolution of NM-212, a solvothermally synthesized nanoceria material, and a calcined form of the solvothermally synthesized nanoceria material (ca. 40, 4, and 40 nm diameter, respectively) was investigated. Two dissolution methods were employed. Dissolution of NM-212 and the calcined nanoceria was much slower than that of the non-calcined form. The decreased solubility was attributed to an increased amount of surface Ce4+ species induced by the high temperature. Carboxylic acids doubled the very low dissolution rate of NM-212. Nanoceria dissolution releases Ce3+ ions, which, with phosphate, form insoluble cerium phosphate in vivo. The addition of immobilized phosphates did not accelerate nanoceria dissolution, suggesting that the Ce3+ ion release during nanoceria dissolution was phosphate-independent. Smaller particles resulting from partial nanoceria dissolution led to less cellular protein carbonyl formation, attributed to an increased amount of surface Ce3+ species. Surface reactivity was greater for the solvothermally synthesized nanoceria, which had more Ce3+ species at the surface. The results show that temperature treatment of nanoceria can produce significant differences in solubility and surface cerium valence, which affect the biological and catalytic properties of nanoceria.
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Affiliation(s)
- Robert A Yokel
- Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky, 40536-0596, USA
| | | | | | - Matthew L Hancock
- Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky, 40506-0046, USA
| | - Jason M Unrine
- Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky, 40546-0091, USA
| | | | - Eric A Grulke
- Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky, 40506-0046, USA
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Keller JG, Graham UM, Koltermann-Jülly J, Gelein R, Ma-Hock L, Landsiedel R, Wiemann M, Oberdörster G, Elder A, Wohlleben W. Author Correction: Predicting dissolution and transformation of inhaled nanoparticles in the lung using abiotic flow cells: The case of barium sulphate. Sci Rep 2021; 11:8813. [PMID: 33875670 PMCID: PMC8055969 DOI: 10.1038/s41598-021-82185-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Johannes G Keller
- Department Experimental Toxicology and Ecology and Department Material Physics, BASF SE, 67056, Ludwigshafen, Germany.,Institute of Pharmacy, Faculty of Biology, Chemistry & Pharmacy, Freie Universität Berlin, 14195, Berlin, Germany
| | - Uschi M Graham
- National Institute of Occupational Safety and Health, Cincinnati, Ohio, 45226, USA
| | - Johanna Koltermann-Jülly
- Department Experimental Toxicology and Ecology and Department Material Physics, BASF SE, 67056, Ludwigshafen, Germany.,Biopharmaceutics and Pharmaceutical Technology, Saarland University, 66123, Saarbrücken, Germany
| | - Robert Gelein
- University of Rochester Medical Center, Rochester, New York, USA
| | - Lan Ma-Hock
- Department Experimental Toxicology and Ecology and Department Material Physics, BASF SE, 67056, Ludwigshafen, Germany
| | - Robert Landsiedel
- Department Experimental Toxicology and Ecology and Department Material Physics, BASF SE, 67056, Ludwigshafen, Germany
| | - Martin Wiemann
- IBE R&D Institute for Lung Health gGmbH, Mendelstr. 11, 48149, Münster, Germany
| | | | - Alison Elder
- University of Rochester Medical Center, Rochester, New York, USA.
| | - Wendel Wohlleben
- Department Experimental Toxicology and Ecology and Department Material Physics, BASF SE, 67056, Ludwigshafen, Germany.
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Ma-Hock L, Sauer UG, Ruggiero E, Keller JG, Wohlleben W, Landsiedel R. The Use of Nanomaterial In Vivo Organ Burden Data for In Vitro Dose Setting. Small 2021; 17:e2005725. [PMID: 33586349 DOI: 10.1002/smll.202005725] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/05/2021] [Indexed: 06/12/2023]
Abstract
Effects of nanomaterials are usually observed at higher concentrations in vitro compared to animal studies. This is pointing to differences between in vivo situations and generally less complex in vitro models. These differences concern toxicodynamics and the internal exposure (at the target cells of the in vitro and in vivo test system). The latter can be minimized by appropriate in vivo to in vitro dose extrapolations (IVIVE). An IVIVE six-step procedure is proposed here: 1) determine in vivo exposure; 2) identify in vivo organ burden at lowest observed adverse effect concentration; 3) extrapolate in vivo organ burden to in vitro effective dose; 4) extrapolate in vitro effective dose to nominal concentration; 5) set dose ranges to establish dose-response relationships; and 6) consider uncertainties and specificities of in vitro test system. Assessing the results of in vitro studies needs careful consideration of discrepancies between in vitro and in vivo models: apart from different endpoints (usually cellular responses in vitro and adverse effects on organs or organisms in vivo), nanomaterials can also have a different potency in relatively simple in vitro models and the more complex corresponding organ in vivo. IVIVE can, nonetheless, reduce the differences in exposures.
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Affiliation(s)
- Lan Ma-Hock
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen, Germany
| | - Ursula G Sauer
- Scientific Consultancy-Animal Welfare, Hallstattfeld 16, 85579, Neubiberg, Germany
| | - Emmanuel Ruggiero
- Department of Material Physics, BASF SE, 67056, Ludwigshafen, Germany
| | | | - Wendel Wohlleben
- Department of Material Physics, BASF SE, 67056, Ludwigshafen, Germany
| | - Robert Landsiedel
- Experimental Toxicology and Ecology, BASF SE, 67056, Ludwigshafen, Germany
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43
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Llewellyn SV, Kämpfer A, Keller JG, Vilsmeier K, Büttner V, Ag Seleci D, Schins RPF, Doak SH, Wohlleben W. Simulating Nanomaterial Transformation in Cascaded Biological Compartments to Enhance the Physiological Relevance of In Vitro Dosing Regimes: Optional or Required? Small 2021; 17:e2004630. [PMID: 33475244 DOI: 10.1002/smll.202004630] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/09/2020] [Indexed: 06/12/2023]
Abstract
Would an engineered nanomaterial (ENM) still have the same identity once it reaches a secondary target tissue after a journey through several physiological compartments? Probably not. Does it matter? ENM pre-treatments may enhance the physiological relevance of in vitro testing via controlled transformation of the ENM identity. The implications of material transformation upon reactivity, cytotoxicity, inflammatory, and genotoxic potential of Ag and SiO2 ENM on advanced gastro-intestinal tract cell cultures and 3D liver spheroids are demonstrated. Pre-treatments are recommended for certain ENM only.
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Affiliation(s)
- Samantha V Llewellyn
- In vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, Wales, SA2 8PP, UK
| | - Angela Kämpfer
- IUF-Leibniz Research Institute for Environmental Medicine, Auf'm Hennekamp 50, Düsseldorf, 40225, Germany
| | - Johannes G Keller
- Advanced Materials Research, Department of Material Physics and Analytics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, 67056, Germany
| | - Klaus Vilsmeier
- Advanced Materials Research, Department of Material Physics and Analytics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, 67056, Germany
| | - Veronika Büttner
- IUF-Leibniz Research Institute for Environmental Medicine, Auf'm Hennekamp 50, Düsseldorf, 40225, Germany
| | - Didem Ag Seleci
- Advanced Materials Research, Department of Material Physics and Analytics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, 67056, Germany
| | - Roel P F Schins
- IUF-Leibniz Research Institute for Environmental Medicine, Auf'm Hennekamp 50, Düsseldorf, 40225, Germany
| | - Shareen H Doak
- In vitro Toxicology Group, Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, Swansea, Wales, SA2 8PP, UK
| | - Wendel Wohlleben
- Advanced Materials Research, Department of Material Physics and Analytics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, 67056, Germany
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Hammer T, Bossa N, Persson M, Wichser A, Lehner K, Ruggiero E, Fonseca AS, Jovic M, Gaan S, Wohlleben W, Wang J. Importance of the number emission factor of combustion-generated aerosols from nano-enabled products. NanoImpact 2021; 22:100307. [PMID: 35559964 DOI: 10.1016/j.impact.2021.100307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/09/2021] [Accepted: 02/25/2021] [Indexed: 06/15/2023]
Abstract
Accidental or open waste burning and incineration of nano-enabled products (NEPs) might lead to the release of incidental aerosols in the nano size range into the environment resulting in harmful effects on humans. We have investigated combustion-generated aerosol release during accidental burning for several real-life NEPs such as paints with silica (SiO2) and spruce wood panels containing SiO2 and Fe2O3 nanomaterials (NMs), paper with SiO2 and Fe2O3 NMs and polymeric composites with CuPhthtalocyanine NMs in poly lactic acid (PLA), polyamide 6 (PA6) and thermoplastic pol-urethane (TPU) matrices. Chemical compositions, aerosols number emission factors (nefs) and concentrations of the signature elements of the NMs of the combustion-generated aerosols were investigated. In addition, the residual ash was analyzed. The outcomes of this study shed light on how NM and matrix types influenced the properties of the released aerosols. Based on our results it was established that the combustion-generated aerosols were composed of transformed NMs with modified physical-chemical characteristics compared to the pristine NMs. In addition to aerosols with transformed NMs, there were also particles due to incomplete combustion of the matrix. Types of the pristine NMs and matrices affected the characteristics of the released aerosols. Since the effect of the aerosols is related to the inhaled aerosol number concentration, the nef is an important parameter. Our results showed that the nefs in the size range of 5.6 to 560 nm depended strongly on the type of combusted NEP, which indicated that the NEPs could be categorized according to their potential to release aerosols in this size range when they were burnt. The generated release data facilitate the assessment of human and environmental exposure and the associated risk assessment of combustion-generated aerosols from NEPs.
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Affiliation(s)
- Tobias Hammer
- Institute of Environmental Engineering, ETH Zürich, 8093 Zürich, Switzerland; Laboratory of Advanced Analytical Technologies, Empa, 8600 Dübendorf, Switzerland
| | - Nathan Bossa
- Leitat Technological Center, 08225 Terrassa, Barcelona, Spain
| | | | - Adrian Wichser
- Laboratory of Advanced Analytical Technologies, Empa, 8600 Dübendorf, Switzerland
| | - Ken Lehner
- Laboratory of Advanced Analytical Technologies, Empa, 8600 Dübendorf, Switzerland
| | | | - Ana Sofia Fonseca
- National Research Centre for the Working Environment (NRCWE), Lerso Parkallé 105, DK-2100 Copenhagen, Denmark
| | - Milijana Jovic
- Laboratory of Advanced Fibers, Empa, 9014 Sankt Gallen, Switzerland
| | - Sabyasachi Gaan
- Laboratory of Advanced Fibers, Empa, 9014 Sankt Gallen, Switzerland
| | | | - Jing Wang
- Institute of Environmental Engineering, ETH Zürich, 8093 Zürich, Switzerland; Laboratory of Advanced Analytical Technologies, Empa, 8600 Dübendorf, Switzerland.
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Sauer UG, Werle K, Waindok H, Hirth S, Hachmöller O, Wohlleben W. Critical Choices in Predicting Stone Wool Biodurability: Lysosomal Fluid Compositions and Binder Effects. Chem Res Toxicol 2021; 34:780-792. [PMID: 33464877 DOI: 10.1021/acs.chemrestox.0c00401] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The hazard potential, including carcinogenicity, of inhaled man-made vitreous fibers (MMVFs) is correlated with their biodurability in the lung, as prerequisite for biopersistence. Abiotic dissolution testing serves to predict biodurability. We re-analyzed the International Agency for Research on Cancer Monograph on MMVFs and found that the correlation between in vivo biopersistence and abiotic dissolution presented therein confounded different simulant fluids and further confounded evaluation of leaching vs structural elements. These are critical choices for abiotic dissolution testing, as are binder removal and the rate of the flow that removes ions during testing. Therefore, we experimentally demonstrated how fluid composition and binder affect abiotic dissolution of a representative stone wool MMVF. We compared six simulant fluids (all pH 4.5, reflecting the environment of alveolar macrophage lysosomes) that differed in organic acids, which have a critical role in their ability to modulate the formation of Si-rich gels on the fiber surfaces. Removing the binder accelerates the average dissolution rate by +104% (max. + 273%) across the fluids by suppression of gel formation. Apart from the high-citrate fluid that predicted a 10-fold faster dissolution than is observed in vivo, none of the five other fluids resulted in dissolution rates above 400 ng/cm2/h, the limit associated with the exoneration from classification for carcinogenicity in the literature. These findings were confirmed with and without binder. For corroboration, five more stone wool MMVFs were assessed with and without binder in one specific fluid. Again, the presence of the binder caused gel formation and reduced dissolution rates. To enhance the reliability and robustness of abiotic predictions of biodurability, we recommend replacing the critically influential citric acid in pH 4.5 fluids with other organic acids. Also, future studies should consider structural transformations of the fibers, including changes in fiber length, fiber composition, and reprecipitation of gel layers.
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Affiliation(s)
- Ursula G Sauer
- Scientific Consultancy - Animal Welfare, 85579 Neubiberg, Germany
| | - Kai Werle
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Hubert Waindok
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Sabine Hirth
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Oliver Hachmöller
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
| | - Wendel Wohlleben
- Department of Material Physics and Analytics, BASF SE, Advanced Materials Research, 67056 Ludwigshafen, Germany
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Hirth S, Waindok H, Wohlleben W. Which fraction of stone wool fibre surface remains uncoated by binder? A detailed analysis by time-of-flight secondary ion mass spectrometry and X-ray photoelectron spectroscopy. RSC Adv 2021; 11:39545-39552. [PMID: 35492464 PMCID: PMC9044424 DOI: 10.1039/d1ra06251d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/25/2021] [Indexed: 11/21/2022] Open
Abstract
ToF-SIMS mapping reveals that man-made vitreous fibres (MMVF) are fully covered with binder explaining variations in biodurability testing with simulated lung fluid described earlier.
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Affiliation(s)
- Sabine Hirth
- BASF SE, Carl-Bosch-Straße 38, 67056 Ludwigshafen am Rhein, Germany
| | - Hubert Waindok
- BASF SE, Carl-Bosch-Straße 38, 67056 Ludwigshafen am Rhein, Germany
| | - Wendel Wohlleben
- BASF SE, Carl-Bosch-Straße 38, 67056 Ludwigshafen am Rhein, Germany
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47
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Janer G, Landsiedel R, Wohlleben W. Rationale and decision rules behind the ECETOC NanoApp to support registration of sets of similar nanoforms within REACH. Nanotoxicology 2020; 15:145-166. [PMID: 33320695 DOI: 10.1080/17435390.2020.1842933] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
New registration requirements for nanomaterials under REACH consider the possibility to form 'sets of similar nanoforms' for a joined human health and environmental hazard, exposure and risk assessment. We developed a tool to create and justify sets of similar nanoforms and to ensure that each of the nanoforms is sufficiently similar to all other nanoforms. The decision logic is following the ECHA guidance in a transparent and evidence-based manner. For each two nanoforms the properties under consideration are compared and corresponding thresholds for maximal differences are proposed. In tier1, similarity is assessed based on intrinsic properties that mostly correspond to those required for nanoform identification under REACH: composition, impurities/additives, size, crystallinity, shape and surface treatment. Moreover, potential differences in the agglomeration/aggregation state resulting from different production processes are considered. If nanoforms were not sufficiently similar based on tier1 criteria, additional data from functional assays are required in tier2. In rare cases, additional short-term in vivo rodent data could be required in a third tier. Data required by tier 2 are triggered by the intrinsic properties in the first tier that did not match the similarity criteria. Most often this will be data on dissolution and surface reactivity followed by in vitro toxicity, dispersion stability, dustiness. Out of several nanoforms given by the user, the tool concludes which nanoforms could be justified to be in the same set and which nanoforms are outside. It defines the boundaries of sets of similar nanoforms and generates a justification for the REACH registration.
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Affiliation(s)
- Gemma Janer
- Leitat Technological Center, Barcelona, Spain
| | - Robert Landsiedel
- Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen am Rhein, Germany
| | - Wendel Wohlleben
- Department of Material Physics and Analytics, BASF SE, Ludwigshafen am Rhein, Germany
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Zhang Z, Kappenstein O, Ebner I, Ruggiero E, Müller P, Luch A, Wohlleben W, Haase A. Investigating ion-release from nanocomposites in food simulant solutions: Case studies contrasting kaolin, CaCO3 and Cu-phthalocyanine. Food Packag Shelf Life 2020. [DOI: 10.1016/j.fpsl.2020.100560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Goodwin DG, Shen SJ, Lyu Y, Lankone R, Barrios AC, Kabir S, Perreault F, Wohlleben W, Nguyen T, Sung L. Graphene/polymer nanocomposite degradation by ultraviolet light: The effects of graphene nanofillers and their potential for release. Polym Degrad Stab 2020; 182:10.1016/j.polymdegradstab.2020.109365. [PMID: 36936609 PMCID: PMC10021000 DOI: 10.1016/j.polymdegradstab.2020.109365] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ultraviolet (UV)-induced degradation of graphene/polymer nanocomposites was investigated in this study. Specifically, the effect of few-layer graphene nanofillers on the degradation of a thermoplastic polyurethane (TPU) and the release potential of graphene from the degraded nanocomposite surfaces were assessed. Graphene/TPU (G/TPU) nanocomposites and neat TPU were UV-exposed under both dry and humid conditions in the NIST SPHERE, a precisely controlled, high intensity UV-weathering device. Neat TPU and G/TPU were characterized over the time course of UV exposure using color measurements and infrared spectroscopy, for appearance and chemical changes, respectively. Changes in thickness and surface morphology were obtained with scanning electron microscopy. A new fluorescence quenching measurement approach was developed to identify graphene sheets at the nanocomposite surface, which was supported by contact angle measurements. The potential for graphene release from the nanocomposite surface was evaluated using a tape-lift method followed by microscopy of any particles present on the tape. The findings suggest that graphene improves the service life of TPU with respect to UV exposure, but that graphene becomes exposed at the nanocomposite surface over time, which may potentially lead to its release when exposed to small mechanical forces or upon contact with other materials.
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Affiliation(s)
- David G. Goodwin
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
- Corresponding author. (D.G. Goodwin Jr)
| | - Shih-Jia Shen
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
| | - Yadong Lyu
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
| | - Ronald Lankone
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
| | - Ana C. Barrios
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
- School of Sustainable Engineering and the Built Environment, Arizona State University, 660 S. College Ave, Tempe, AZ, 85281
| | - Samir Kabir
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
| | - François Perreault
- School of Sustainable Engineering and the Built Environment, Arizona State University, 660 S. College Ave, Tempe, AZ, 85281
| | - Wendel Wohlleben
- BASF SE, Dept. Material Physics & Analytics, Carl-Bosch-Strasse 38, Ludwigshafen, 67056, Germany
| | - Tinh Nguyen
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
| | - Lipiin Sung
- National Institute of Standards and Technology, Materials and Structural Systems Division, Engineering Laboratory, Gaithersburg, MD, 20899, USA
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Keller JG, Quevedo DF, Faccani L, Costa AL, Landsiedel R, Werle K, Wohlleben W. Dosimetry in vitro - exploring the sensitivity of deposited dose predictions vs. affinity, polydispersity, freeze-thawing, and analytical methods. Nanotoxicology 2020; 15:21-34. [PMID: 33100120 DOI: 10.1080/17435390.2020.1836281] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Dose-response by in vitro testing is only valid if the fraction of the particle dose that deposits onto adherent cells is known. Modeling tools such as the 'distorted grid' (DG) code are common practices to predict that fraction. As another challenge, workflow efficiency depends on parallelized sample preparation, for which freeze-thaw protocols have been explored earlier, but not their implications on dosimetry. Here we assess the sensitivity of the DG code toward freeze-thaw protocols and variations in user-defined parameters, including the estimation of particle-cell affinity and determination of agglomerate size, which we measure by DLS or AUC. We challenge the sensitivity by materials of varying composition, surface functionalization, and size (TiO2, CeO2, BaSO4, 2x Ag, 3x SiO2). We found that the average effective density is robust, but the dose predictions by different approaches varied typically 2-fold and up to 10-fold; this uncertainty translates directly into the uncertainty of no-effect-concentrations. The use of standardized dispersion protocols increases the uncertainty in doses. The choice of a measurement method and minor details of the particle size distribution strongly influence the modeled dosimetry. Uncertainty is high for very well dispersed nanomaterials; since then, the assumed affinity of particles to cells has a decisive influence. Against this background, the modulation of deposited dose by freeze-thaw protocols is a minor factor that can be controlled by aligning the protocols of sample preparation. However, even then, the uncertainty of deposited doses must be considered when comparing the in vitro toxicity of different nanomaterials.
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Affiliation(s)
- Johannes G Keller
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Daniel F Quevedo
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Lara Faccani
- Institute of Science and Technology for Ceramics, CNR-ISTEC-National Research Council of Italy, Faenza, Italy.,University of Parma, Parma, Italy
| | - Anna L Costa
- Institute of Science and Technology for Ceramics, CNR-ISTEC-National Research Council of Italy, Faenza, Italy
| | - Robert Landsiedel
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Kai Werle
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Wendel Wohlleben
- Department of Material Physics and Department of Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
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