1
|
Bossa N, Delpivo C, Sipe JM, Gao L, Pomar V, Miralles GS, Fonseca AS, Jensen KA, Vazquez-Campos S. Indoor paint life cycle particle release: Safer-by-design products and the importance of choosing the right formula. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174155. [PMID: 38942309 DOI: 10.1016/j.scitotenv.2024.174155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/28/2024] [Accepted: 06/18/2024] [Indexed: 06/30/2024]
Abstract
In 2020, the European Commission published a regulation that states all producers of white paints containing titanium dioxide (TiO2) must provide a warning label on their products. Exposure during the production and application of products containing TiO2 can be harmful, and therefore these products must be labeled as "may cause cancer." The paint industry is a major user of TiO2 pigment. This study focuses on pigment release from three TiO2-based paints and discusses the effect of paint formulation, more precisely the Pigment Volume Concentration (PVC), to predict TiO2 pigment release from the paints during a simulated use phase and at the end of life (EoL). The use phase considered mild abrasion of painted panels that simulated cleaning or touching. The EoL phase was studied using leaching tests simulating landfill disposal. TiO2 release during both activities was evident with a high discrepancy between the three paints. While dry rubbing was similar for all paints, activities involving water present a high release link to paint matrix degradation. The paint pigment volume concentration and the paint permeability determines the TiO2 release during wet rubbing and leaching. This work represents an attempt to identify the paint permeability as a matrix-related parameter to predict TiO2 release and a way to use of this parameter to develop safer products.
Collapse
Affiliation(s)
- Nathan Bossa
- LEITAT Technological Center, C/Pallars 179-185, 08005 Barcelona, Spain; Department of Civil and Environmental Engineering, Duke University, Durham, NC 27708, USA.
| | - Camila Delpivo
- LEITAT Technological Center, C/Pallars 179-185, 08005 Barcelona, Spain
| | - Joana Marie Sipe
- Department of Civil and Environmental Engineering, Duke University, Durham, NC 27708, USA
| | - Lijia Gao
- Department of Civil and Environmental Engineering, Duke University, Durham, NC 27708, USA
| | - Vicenç Pomar
- LEITAT Technological Center, C/Pallars 179-185, 08005 Barcelona, Spain
| | | | - Ana Sofia Fonseca
- National Research Centre for the Working Environment (NRCWE), Lerso Parkallé 105, DK-2100, Copenhagen, Denmark
| | - Keld Alstrup Jensen
- National Research Centre for the Working Environment (NRCWE), Lerso Parkallé 105, DK-2100, Copenhagen, Denmark
| | | |
Collapse
|
2
|
Wohlleben W, Bossa N, Mitrano DM, Scott K. Everything falls apart: How solids degrade and release nanomaterials, composite fragments, and microplastics. NANOIMPACT 2024; 34:100510. [PMID: 38759729 DOI: 10.1016/j.impact.2024.100510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 05/05/2024] [Accepted: 05/08/2024] [Indexed: 05/19/2024]
Abstract
To ensure the safe use of materials, one must assess the identity and quantity of exposure. Solid materials, such as plastics, metals, coatings and cements, degrade to some extent during their life cycle, and releases can occur during manufacturing, use and end-of-life. Releases (e.g., what is released, how does release happen, and how much material is released) depend on the composition and internal (nano)structures of the material as well as the applied stresses during the lifecycle. We consider, in some depth, releases from mechanical, weathering and thermal stresses and specifically address the use cases of fused-filament 3D printing, dermal contact, food contact and textile washing. Solid materials can release embedded nanomaterials, composite fragments, or micro- and nanoplastics, as well as volatile organics, ions and dissolved organics. The identity of the release is often a heterogenous mixture and requires adapted strategies for sampling and analysis, with suitable quality control measures. Control materials enhance robustness by enabling comparative testing, but reference materials are not always available as yet. The quantity of releases is typically described by time-dependent rates that are modulated by the nature and intensity of the applied stress, the chemical identity of the polymer or other solid matrix, and the chemical identity and compatibility of embedded engineered nanomaterials (ENMs) or other additives. Standardization of methods and the documentation of metadata, including all the above descriptors of the tested material, applied stresses, sampling and analytics, are identified as important needs to advance the field and to generate robust, comparable assessments. In this regard, there are strong methodological synergies between the study of all solid materials, including the study of micro- and nanoplastics. From an outlook perspective, we review the hazard of the released entities, and show how this informs risk assessment. We also address the transfer of methods to related issues such as tyre wear, advanced materials and advanced manufacturing, biodegradable polymers, and non-solid matrices. As the consideration of released entities will become more routine in industry via lifecycle assessment in Safe-and-Sustainable-by-Design practices, release assessments will require careful design of the study with quality controls, the use of agreed-on test materials and standardized methods where these exist and the adoption of clearly defined data reporting practices that enable data reuse, meta-analyses, and comparative studies.
Collapse
Affiliation(s)
- Wendel Wohlleben
- BASF SE, Dept. of Analytical and Materials Science, 67056 Ludwigshafen, Germany.
| | - Nathan Bossa
- TEMAS Solutions GmbH, Lätterweg 5, 5212 Hausen, Switzerland; Department of Civil & Environmental Engineering, Duke University, Durham, NC 27708, United States
| | - Denise M Mitrano
- Environmental Systems Science Department, ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland
| | - Keana Scott
- Materials Measurement Science Division, National Institute of Standards and Technology, 100 Bureau Drive, MS-8372, Gaithersburg, MD 20899, United States
| |
Collapse
|
3
|
Soto Beobide A, Bieri R, Szakács Z, Sparwasser K, Kaitsa IG, Georgiopoulos I, Andrikopoulos KS, Van Kerckhove G, Voyiatzis GA. Raman Spectroscopy Unfolds the Fate and Transformation of SWCNTs after Abrasive Wear of Epoxy Floor Coatings. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:120. [PMID: 38202575 PMCID: PMC10780583 DOI: 10.3390/nano14010120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/21/2023] [Accepted: 12/30/2023] [Indexed: 01/12/2024]
Abstract
Nanomaterials are integrated within consumer products to enhance specific properties of interest. Their release throughout the lifecycle of nano-enabled products raises concerns; specifically, mechanical strains can lead to the generation of fragmented materials containing nanomaterials. We investigated the potential release of single-walled carbon nanotubes (SWCNTs-brand TUBALL™) from epoxy composite materials. A pin-on-disk-type tribometer was used for the accelerated mechanical aging of the nanocomposites. A pristine nanocomposite material, abraded material and debris obtained from the abrasion in the tribometer were analyzed by Raman spectroscopy. The airborne-produced particles were captured using particle collectors. Stat Peel's Identifier C2 system was used to monitor the SWCNT content of respirable particles produced during the abrasion test. The SWCNT amounts found were below the LoQ. The Raman spectra conducted on the Stat Peel filters helped identify the presence of free SWCNTs released from the epoxy matrix, although they were notably scarce. Raman spectroscopy has been proved to be a crucial technique for the identification, characterization and assessment of structural changes and degradation in SWCNTs that occurred during the abrasion experiments.
Collapse
Affiliation(s)
- Amaia Soto Beobide
- Foundation for Research and Technology-Hellas (FORTH), Institute of Chemical Engineering Sciences (ICE-HT), Stadiou Str., 265 04 Rio-Patras, Greece; (K.S.A.); (G.A.V.)
| | - Rudolf Bieri
- Stat Peel Ltd., Stampfgasse 4, CH-8750 Glarus, Switzerland; (R.B.); (Z.S.)
| | - Zoltán Szakács
- Stat Peel Ltd., Stampfgasse 4, CH-8750 Glarus, Switzerland; (R.B.); (Z.S.)
| | - Kevin Sparwasser
- Stat Peel Ltd., Stampfgasse 4, CH-8750 Glarus, Switzerland; (R.B.); (Z.S.)
| | - Ioanna G. Kaitsa
- Department of Physics, University of Patras, 265 04 Rio-Patras, Greece;
| | - Ilias Georgiopoulos
- MIRTEC S.A., Thiva Branch, 76th km of Athens-Lamia National Road, 320 09 Schimatari, Greece;
| | - Konstantinos S. Andrikopoulos
- Foundation for Research and Technology-Hellas (FORTH), Institute of Chemical Engineering Sciences (ICE-HT), Stadiou Str., 265 04 Rio-Patras, Greece; (K.S.A.); (G.A.V.)
- Department of Physics, University of Patras, 265 04 Rio-Patras, Greece;
| | | | - George A. Voyiatzis
- Foundation for Research and Technology-Hellas (FORTH), Institute of Chemical Engineering Sciences (ICE-HT), Stadiou Str., 265 04 Rio-Patras, Greece; (K.S.A.); (G.A.V.)
| |
Collapse
|
4
|
Zhao Y, Goodwin DG, Sung L, Ramakrishnan G, Wu Q, Cen J, Petersen EJ, Orlov A. Quantitative evaluation of released nanomaterials from carbon nanotube epoxy nanocomposites during environmental exposure and mechanical treatment. NANOIMPACT 2023; 32:100486. [PMID: 37777181 DOI: 10.1016/j.impact.2023.100486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/17/2023] [Accepted: 09/27/2023] [Indexed: 10/02/2023]
Abstract
Carbon nanotubes (CNTs) are promising nanomaterials exhibiting high thermal and electrical conductivities, significant stiffness, and high tensile strength. As a result, CNTs have been utilized as additives to enhance properties of various polymeric materials in a broad range of fields. In this study, we investigated the release of CNTs from CNT epoxy nanocomposites exposed to environmental weathering and mechanical stresses. The presence and amount of CNTs released from degraded polymer nanocomposites is important because CNTs can impact physiological systems in humans and environmental organisms. The weathering experiments in this study included nanocomposite exposure to both UV and a water spray, to simulate sunlight and rain exposure, whereas mechanical stresses were induced by shaking and ultrasonication. CNT release from epoxy nanocomposites was quantified by a 14C-labeling method that enabled measurement of the CNT release rates after different weathering and mechanical treatments. In this study, a sample oxidizer was used prior to liquid scintillation counting, because it was shown to reduce interferences from the presence of polymeric materials and achieve a high recovery (95%). Polymer nanocomposite degradation was confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and light microscopy. A continuous release of 14C-labeled nanomaterials was observed after each UV and simulated rain exposure period, with 0.23% (mass/mass) of the total embedded mass of CNTs being released from the CNT nanocomposite during the full weathering process, suggesting that the water spray induced sufficient mechanical stress to eliminate the protective effect of the surface agglomerated CNT network. Importantly, additional mechanical stresses imposed on the weathered nanocomposites by shaking and ultrasonication resulted in further release of approximately 0.27% (mass /mass).
Collapse
Affiliation(s)
- Yue Zhao
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, USA
| | - David G Goodwin
- Engineering Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA
| | - Lipiin Sung
- Engineering Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA
| | - Girish Ramakrishnan
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Qiyuan Wu
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Jiajie Cen
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Elijah J Petersen
- Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA.
| | - Alexander Orlov
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, NY 11794, USA.
| |
Collapse
|
5
|
Bossa N, Sipe JM, Berger W, Scott K, Kennedy A, Thomas T, Hendren CO, Wiesner MR. Quantifying Mechanical Abrasion of MWCNT Nanocomposites Used in 3D Printing: Influence of CNT Content on Abrasion Products and Rate of Microplastic Production. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10332-10342. [PMID: 34264058 PMCID: PMC10084403 DOI: 10.1021/acs.est.0c02015] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Manufactured nanomaterials (MNMs) are incorporated as "nanofillers" into consumer products to enhance properties of interest. Multiwalled carbon nanotubes (MWCNTs) are known for their unique properties and have many applications in polymers. However, the release of MWCNTs during the nanoenabled product life cycle is concerning. During the use phase, mechanical stresses can produce fragmented materials containing MNMs. The degree of MNM release, the resulting exposure to these materials, and the potential impacts of their release are active research topics. In this study, we describe methodological improvements to study the abrasion of plastics containing MNMs (nanocomposites) and report on characteristics of abrasion products produced and rates of microplastic production. The abrasion device developed for this work allows for the measurement of power inputs to determine scaled release rates. Abrasion rates for plastics used in 3D printing were found to be 0.27 g/m2/s for the PETG polymer and 0.3 g/m2/s for the 2% MWCNT-PETG nanocomposite. Embedded and protuberant MWCNTs appeared to impact the particle size, shape, hydrophobicity, and surface charge of the microplastics, while the inclusion of MWCNTs had a small effect on microplastic production. Measurements of power input to the abrasion process provided a basis for estimating microplastic production rates for these nanocomposites.
Collapse
Affiliation(s)
- Nathan Bossa
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, 27708, USA
- Human & Environmental Health &Safety Group Materials Safety Unit, Leitat Technological Center, Carrer de la Innovació, 2, 08225, Terrassa, Spain
| | - Joana Marie Sipe
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, 27708, USA
| | - William Berger
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, 27708, USA
| | - Keana Scott
- Materials Measurement Science Division, National Institute of Standards and Technology, 100 Bureau Drive, MS-8372 Gaithersburg, MD 20899, United States
| | - Alan Kennedy
- US Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Rd. Vicksburg, MS, USA
| | - Treye Thomas
- United States Consumer Product Safety Commission, 4330 East-West Highway, Bethesda, Maryland 20814, United States
| | - Christine Ogilvie Hendren
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, 27708, USA
- Department of Geological and Environmental Sciences, Appalachian State University, 287 Rivers St, Boone, NC 28608, USA
| | - Mark R. Wiesner
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, 27708, USA
| |
Collapse
|
6
|
Jensen ACØ, Harboe H, Brostrøm A, Jensen KA, Fonseca AS. Nanoparticle Exposure and Workplace Measurements During Processes Related to 3D Printing of a Metal Object. Front Public Health 2020; 8:608718. [PMID: 33324605 PMCID: PMC7723871 DOI: 10.3389/fpubh.2020.608718] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 10/23/2020] [Indexed: 12/12/2022] Open
Abstract
Metal 3D printing has many potential uses within prototyping and manufacturing. Selective laser melting (SLM) is a process that uses metal powders in the micrometer range as printing material. The particle release from the entire SLM printing process is not well-studied. While the 3D printing itself often occurs in a sealed chamber, activities related to the process can potentially release harmful metal particles to the indoor working environment through resuspension of the printing powder or via incident nanoparticles generated during printing. The objective of this study was to improve the understanding of particle exposure in work processes associated with 3D printing and potential needs for interventions by a case study conducted in a 3D printing facility. In this setting, direct release and dispersion of particles throughout the workspace from processes related to metal 3D printing was investigated. The release from five activities were studied in detail. The activities included post-printing cleaning, object annealing, and preparation of new base substrate for the next printing was. Three of the five measured activities caused particles number concentrations in the working environment to increase above background levels which were found to be 8·102 cm-3. Concentrations during chamber emptying and the open powder removal system (PRS) cleaning processes increased to 104 and 5·103 cm-3, respectively, whereas grinding activity increased number concentrations to 2.5·105 cm-3. Size distributions showed that particles were mainly smaller than 200 nm. Respirable mass concentrations were 50.4 μg m-3, collected on filters. This was corroborated by respirable mass measured with a DustTrak of 58.4 μg m-3. Respirable mass concentrations were below the occupational exposure limits in Denmark for an 8 h time-weighted average.
Collapse
Affiliation(s)
| | | | - Anders Brostrøm
- Technical University of Denmark, DTU Nanolab - National Centre for Nano Fabrication and Characterization, Kgs Lyngby, Denmark
| | - Keld A Jensen
- The National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Ana S Fonseca
- The National Research Centre for the Working Environment, Copenhagen, Denmark
| |
Collapse
|
7
|
Sanding and analysis of dust from nano-silica filled composite resins for stereolithography. Chem Eng Res Des 2020. [DOI: 10.1016/j.cherd.2020.01.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
|
8
|
Lovreglio P, Stufano A, Mele D, Acquafredda P, Cottica D, Gardinali F, Vimercati L, Soleo L, De Palma G. Occupational exposure to carbon fibers impregnated with epoxy resins and evaluation of their respirability. Inhal Toxicol 2020; 32:63-67. [PMID: 32197573 DOI: 10.1080/08958378.2020.1735582] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Objectives: The study aims to investigate occupational exposure to carbon fibers impregnated with epoxy resins (carbon fiber reinforced [CFR]) in workers at an airplane fuselage section construction plant, by environmental and biological monitoring.Materials and methods: Determination of airborne CFR was done by environmental sampling with active samplers, 11 of which were stationary and 19 personal samplings. The subsequent analyses were performed in the scanning electron microscope fitted with an X-ray microanalysis system (SEM-EDXA). Biological monitoring was carried out by determining CFR in exhaled breath condensate (EBC) collected from 19 male workers who wore personal environmental samplers (exposed workers) and from 10 male workers at the same factory who had no occupational exposure to CFR (internal controls). CFR analysis was done by SEM, applying the method used for determining asbestos fibers in aqueous samples.Results: The airborne CFR concentrations were found to be significantly higher (p = 0.03) at personal samplings (median value 7.01 ff/L, range 1.24-11.16 ff/L) than stationary samplings (median value 1.93 ff/L, range 0.55-10.09 ff/L). The aerodynamic diameters calculated starting from the length and geometric diameter of the sampled CFRs were always higher than 20 µm. CFR was not found in any of the EBC samples collected from the exposed workers and controls.Conclusions: Despite the evidence of occupational exposure to low concentrations of CFR, the absence of such fibers in the EBC in the exposed workers confirms their non-respirability, as expected based on their aerodynamic diameter.
Collapse
Affiliation(s)
- Piero Lovreglio
- Interdisciplinary Department of Medicine, Section of Occupational Medicine, University of Bari, Bari, Italy
| | - Angela Stufano
- Interdisciplinary Department of Medicine, Section of Occupational Medicine, University of Bari, Bari, Italy
| | - Daniela Mele
- Department of Earth and Geo-Environmental Sciences, University of Bari, Bari, Italy
| | - Pasquale Acquafredda
- Department of Earth and Geo-Environmental Sciences, University of Bari, Bari, Italy
| | - Danilo Cottica
- Environmental Research Center, Clinical Scientific Institutes Maugeri SpA SB, Pavia, Italy
| | - Francesco Gardinali
- Environmental Research Center, Clinical Scientific Institutes Maugeri SpA SB, Pavia, Italy
| | - Luigi Vimercati
- Interdisciplinary Department of Medicine, Section of Occupational Medicine, University of Bari, Bari, Italy
| | - Leonardo Soleo
- Interdisciplinary Department of Medicine, Section of Occupational Medicine, University of Bari, Bari, Italy
| | - Giuseppe De Palma
- Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, Section of Public Health and Human Sciences, University of Brescia, Brescia, Italy
| |
Collapse
|
9
|
Gong Z, Pan YL, Videen G, Wang C. Online Characterization of Single Airborne Carbon Nanotube Particles Using Optical Trapping Raman Spectroscopy. APPLIED SPECTROSCOPY 2019; 73:910-916. [PMID: 30654627 DOI: 10.1177/0003702819828809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Carbon nanotubes (CNTs) have become recognized as a potential environmental and health hazard as their applications are broadening and manufacturing costs are reducing. Fundamental information of CNTs in air is of significant importance to our understanding of their environmental fate as well as to further applications. Extensive efforts have been made over decades on characterizing CNTs; however, a majority of the studies are of bulk or CNTs dispersed on substrates. In the present study, we characterize single CNT particles in air using optical trapping Raman spectroscopy (OT-RS). Different types of CNT particles, as well as glassy carbon spheres, were optically trapped in air. Their physical properties were viewed by microscopic bright field images and scattering images; their chemical properties and structural information can be inferred from characteristic Raman bands. The system can also spatially resolve the morphology and chemical distribution of optically trapped CNT particles in air. The OT-RS technique combines single-particle morphological and chemical information and offers an online method to characterize the physicochemical properties of single CNT particles at their native states in air.
Collapse
Affiliation(s)
- Zhiyong Gong
- 1 Department of Physics and Astronomy, Mississippi State University, Starkville, MS, USA
| | - Yong-Le Pan
- 2 U.S. Army Research Laboratory, Adelphi, MD, USA
| | | | - Chuji Wang
- 1 Department of Physics and Astronomy, Mississippi State University, Starkville, MS, USA
| |
Collapse
|
10
|
Kuijpers E, Pronk A, Koivisto AJ, Jensen KA, Vermeulen R, Fransman W. Relative Differences in Concentration Levels during Sawing and Drilling of Car Bumpers Containing MWCNT and Organic Pigment. Ann Work Expo Health 2019; 63:148-157. [PMID: 30615066 DOI: 10.1093/annweh/wxy101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 10/24/2018] [Accepted: 11/27/2018] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION Knowledge on the exposure characteristics, including release of nanomaterials, is especially needed in the later stages of nano-enabled products' life cycles to perform better occupational risk assessments. The objective of this study was to assess the concentrations during sawing and drilling in car bumpers containing multi-walled carbon nanotubes (MWCNTs) and nanosized organic pigment (OP) under variable realistic workplace situations related to the ventilation in the room and machine settings. METHODS Twelve different experiments were performed in triplicate (N = 36) using tools powered by induction engines that allow interference-free particle measurements. A DiSCmini was used to measure particle number concentrations, whereas particle size distributions were measured using Aerodynamic Particle Sizer (TSI), Scanning Mobility Particle Sizer (TSI), and Electrical Low Pressure Impactor (Dekati). In addition, inhalable particles were sampled using IOM samplers on filters for scanning electron microscope/energy-dispersive X-ray spectrometry (SEM/EDX) analyses. Data were analysed to estimate the effects of individual exposure determinants, in a two-stage modelling strategy using Autoregressive Integrated Moving Average models (stage 1) and subsequently combining first stage results in simulations using multiple linear regression models (stage 2). RESULTS In sawing experiments, partly melted carbon-rich particles (mainly ~2 to ~8 µm) were identified with SEM/EDX, whereas drilling experiments revealed no activity-related particles. In addition, no pristine engineered nanoparticles (MWCNTs and OP) were observed to be liberated from the matrix. Statistical analyses showed significant effects of a higher sawing speed, a reduction in air concentration due to mechanical ventilation, and less exposure during sawing of car bumpers containing MWCNTs compared to bumpers containing OP. CONCLUSION The experiments in this study give an indication of the effects of different abrasive activities (sawing, drilling), machine settings (sawing speed, drill size), mechanical ventilation, and material characteristics on the manufactured nano-objects, their agglomerates, and aggregates concentration levels.
Collapse
Affiliation(s)
- Eelco Kuijpers
- TNO, Utrechtseweg 48, HE Zeist, The Netherlands.,Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Yalelaan, CM Utrecht, The Netherlands
| | | | - Antti Joonas Koivisto
- National Research Centre for the Working Environment, Lerso Parkallé, Copenhagen, Denmark
| | - Keld Alstrup Jensen
- National Research Centre for the Working Environment, Lerso Parkallé, Copenhagen, Denmark
| | - Roel Vermeulen
- Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Yalelaan, CM Utrecht, The Netherlands
| | | |
Collapse
|
11
|
Ogura I, Kotake M, Ata S. Quantitative evaluation of carbon nanomaterial releases during electric heating wire cutting and sawing machine cutting of expanded polystyrene-based composites using thermal carbon analysis. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2019; 16:165-178. [PMID: 30427298 DOI: 10.1080/15459624.2018.1540874] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Field measurements were conducted at a facility where expanded polystyrene-based carbon nanomaterial composites, namely, carbon nanotube and carbon black composites, were cut with an electric heating wire cutter or a circular sawing machine. The aerosol particles released during the cutting of the composites were measured using real-time aerosol monitoring, gravimetric analysis, thermal carbon analysis, and scanning electron microscopic observations. This study had two major goals: (1) to quantitatively evaluate the concentrations of airborne carbon nanomaterials during the cutting of their composites; (2) to evaluate the capability of thermal carbon analysis to quantify airborne carbon nanomaterials in the presence of expanded polystyrene-derived particles. The results of thermal carbon analysis showed that the concentrations of elemental carbon (an indicator of carbon nanomaterials) for all the respirable dust samples in both cutting processes were less than the limit of detection (∼2 µg/m3), which is nearly equivalent to or lower than the occupational exposure limits for carbon nanotubes (1 to 50 µg/m3). For total dust, which includes particles larger than respirable size, although the elemental carbon concentrations during heating wire cutting were low (<3 µg/m3), those during sawing machine cutting were up to 58 µg/m3. In scanning electron microscopic observations, micron-sized particles composed of or including carbon nanotubes were detected only in aerosol particles collected during the sawing machine cutting. Therefore, heating wire cutting is considered preferable. This study demonstrated that thermal carbon analysis can quantify airborne carbon nanomaterials in the presence of expanded polystyrene-derived particles.
Collapse
Affiliation(s)
- Isamu Ogura
- a Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology (AIST) , Ibaraki , Japan
- b Technology Research Association for Single Wall Carbon Nanotubes (TASC) , Ibaraki , Japan
| | - Mari Kotake
- b Technology Research Association for Single Wall Carbon Nanotubes (TASC) , Ibaraki , Japan
| | - Seisuke Ata
- b Technology Research Association for Single Wall Carbon Nanotubes (TASC) , Ibaraki , Japan
- c CNT-Application Research Center, National Institute of Advanced Industrial Science and Technology (AIST) , Ibaraki , Japan
| |
Collapse
|
12
|
Stefaniak AB, Bowers LN, Knepp AK, Virji MA, Birch EM, Ham JE, Wells JR, Chaolong Q, Schwegler-Berry D, Friend S, Johnson AR, Martin SB, Qian Y, LeBouf RF, Birch Q, Hammond D. Three-dimensional printing with nano-enabled filaments releases polymer particles containing carbon nanotubes into air. INDOOR AIR 2018; 28:840-851. [PMID: 30101413 PMCID: PMC6398333 DOI: 10.1111/ina.12499] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/03/2018] [Accepted: 08/06/2018] [Indexed: 05/14/2023]
Abstract
Fused deposition modeling (FDM™) 3-dimensional printing uses polymer filament to build objects. Some polymer filaments are formulated with additives, though it is unknown if they are released during printing. Three commercially available filaments that contained carbon nanotubes (CNTs) were printed with a desktop FDM™ 3-D printer in a chamber while monitoring total particle number concentration and size distribution. Airborne particles were collected on filters and analyzed using electron microscopy. Carbonyl compounds were identified by mass spectrometry. The elemental carbon content of the bulk CNT-containing filaments was 1.5 to 5.2 wt%. CNT-containing filaments released up to 1010 ultrafine (d < 100 nm) particles/g printed and 106 to 108 respirable (d ~0.5 to 2 μm) particles/g printed. From microscopy, 1% of the emitted respirable polymer particles contained visible CNTs. Carbonyl emissions were observed above the limit of detection (LOD) but were below the limit of quantitation (LOQ). Modeling indicated that, for all filaments, the average proportional lung deposition of CNT-containing polymer particles was 6.5%, 5.7%, and 7.2% for the head airways, tracheobronchiolar, and pulmonary regions, respectively. If CNT-containing polymer particles are hazardous, it would be prudent to control emissions during use of these filaments.
Collapse
Affiliation(s)
| | - Lauren N. Bowers
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Alycia K. Knepp
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - M. Abbas Virji
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Eileen M. Birch
- National Institute for Occupational Safety and Health, Cincinnati, Ohio
| | - Jason E. Ham
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - J. R. Wells
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Qi Chaolong
- National Institute for Occupational Safety and Health, Cincinnati, Ohio
| | | | - Sherri Friend
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Alyson R. Johnson
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Stephen B. Martin
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Yong Qian
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Ryan F. LeBouf
- National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Quinn Birch
- Department of Chemical and Environmental Engineering, College of Engineering and Applied Science, University of Cincinnati, Cincinnati, Ohio
| | - Duane Hammond
- National Institute for Occupational Safety and Health, Cincinnati, Ohio
| |
Collapse
|
13
|
Bressot C, Aubry A, Pagnoux C, Aguerre-Chariol O, Morgeneyer M. Assessment of functional nanomaterials in medical applications: can time mend public and occupational health risks related to the products' fate? JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2018; 81:957-973. [PMID: 30311864 DOI: 10.1080/15287394.2018.1477271] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Surface coatings are one promising option to prevent bacterial adhesion and biofilm formation given the prevalence of antibiotic resistant bacterial strains. Titanium dioxide (TiO2) is presently considered to be the only photocatalytic material suitable for commercial use, although the toxicity risks of TiO2, particularly in its nanoparticulate form, have not been fully addressed. The aim of this study was to determine release of nanoparticles (NPs) from functional materials for medical applications and their aerosol formation. Further, the fate of the material with respect to its product lifetime was investigated. The present study examined the risk of NP exposure since released submicronic and inhalable manufactured nano-objects, their agglomeraates or aggregates containing Ti were detected. The coating of the material magnifies its emission levels when comparing the obtained product properties to those of an uncoated sample. The evolution of release tendecy with the material's time of use shows that release does not vanish upon continuous material losses induced by the release, thus the risk does not diminish with time. Consequently, this nanomaterial TiO2 needs to be avoided in healthcare settings, or, alternatively, new TiO2-deposition techniques are required to be developed.
Collapse
Affiliation(s)
- Christophe Bressot
- a Direction de risques chroniques , Institut National de l'Environnement Industriel et des Risques (INERIS) , Verneuil en Halatte , France
| | - Alexandra Aubry
- b Sorbonne Universités , Centre d'Immunologie et des Maladies Infectieuses (Cimi-Paris), INSERM , Paris , France
| | | | - Olivier Aguerre-Chariol
- d Direction des Risques Chroniques , Institut National de l'Environnement Industriel et des Risques (INERIS) , Verneuil en Halatte , France
| | - Martin Morgeneyer
- e Sorbonne Universités, Université de Technologie de Compiègne (UTC), Laboratoire Transformations Intégrées de la Matière Renouvelable , Compiègne , France
| |
Collapse
|
14
|
Kovochich M, Fung CCD, Avanasi R, Madl AK. Review of techniques and studies characterizing the release of carbon nanotubes from nanocomposites: Implications for exposure and human health risk assessment. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2018; 28:203-215. [PMID: 28561036 DOI: 10.1038/jes.2017.6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 03/30/2017] [Indexed: 06/07/2023]
Abstract
Composites made with engineered nanomaterials (nanocomposites) have a wide range of applications, from use in basic consumer goods to critical national defense technologies. Carbon nanotubes (CNTs) are a popular addition in nanocomposites because of their enhanced mechanical, thermal, and electrical properties. Concerns have been raised, though, regarding potential exposure and health risks from nanocomposites containing CNTs because of comparisons to other high aspect ratio fibers. Assessing the factors affecting CNT release from composites is therefore paramount for understanding potential exposure scenarios that may occur during product handling and manipulation. Standardized methods for detecting and quantifying released CNTs, however, have not yet been developed. We therefore evaluated experimental approaches deployed by various researchers, with an emphasis on characterizing free versus composite bound CNTs. From our analysis of published studies characterizing CNT releases from nanocomposites, we found that the qualitative and quantitative methods used across studies varied greatly, thus limiting the ability for objective comparison and evaluation of various release factors. Nonetheless, qualitative results indicated that factors such as composite type, CNT functionalization, and energy input during manipulation (i.e., grinding) may affect CNT release. Based on our findings, we offer several recommendations for future product testing and assessment of potential exposure and health risks associated with CNT nanocomposites.
Collapse
Affiliation(s)
| | | | - Raghavendhran Avanasi
- Cardno ChemRisk; 130 Vantis Suite 170, Aliso Viejo, CA, 92656, USA
- ICF; Fairfax, VA, USA
| | - Amy K Madl
- Cardno ChemRisk; 130 Vantis Suite 170, Aliso Viejo, CA, 92656, USA
| |
Collapse
|
15
|
Bishop L, Cena L, Orandle M, Yanamala N, Dahm MM, Birch ME, Evans DE, Kodali VK, Eye T, Battelli L, Zeidler-Erdely PC, Casuccio G, Bunker K, Lupoi JS, Lersch TL, Stefaniak AB, Sager T, Afshari A, Schwegler-Berry D, Friend S, Kang J, Siegrist KJ, Mitchell CA, Lowry DT, Kashon ML, Mercer RR, Geraci CL, Schubauer-Berigan MK, Sargent LM, Erdely A. In Vivo Toxicity Assessment of Occupational Components of the Carbon Nanotube Life Cycle To Provide Context to Potential Health Effects. ACS NANO 2017; 11:8849-8863. [PMID: 28759202 DOI: 10.1021/acsnano.7b03038] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Pulmonary toxicity studies on carbon nanotubes focus primarily on as-produced materials and rarely are guided by a life cycle perspective or integration with exposure assessment. Understanding toxicity beyond the as-produced, or pure native material, is critical, due to modifications needed to overcome barriers to commercialization of applications. In the first series of studies, the toxicity of as-produced carbon nanotubes and their polymer-coated counterparts was evaluated in reference to exposure assessment, material characterization, and stability of the polymer coating in biological fluids. The second series of studies examined the toxicity of aerosols generated from sanding polymer-coated carbon-nanotube-embedded or neat composites. Postproduction modification by polymer coating did not enhance pulmonary injury, inflammation, and pathology or in vitro genotoxicity of as-produced carbon nanotubes, and for a particular coating, toxicity was significantly attenuated. The aerosols generated from sanding composites embedded with polymer-coated carbon nanotubes contained no evidence of free nanotubes. The percent weight incorporation of polymer-coated carbon nanotubes, 0.15% or 3% by mass, and composite matrix utilized altered the particle size distribution and, in certain circumstances, influenced acute in vivo toxicity. Our study provides perspective that, while the number of workers and consumers increases along the life cycle, toxicity and/or potential for exposure to the as-produced material may greatly diminish.
Collapse
Affiliation(s)
- Lindsey Bishop
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
- West Virginia University , Morgantown, West Virginia 26505, United States
| | - Lorenzo Cena
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
- West Chester University , West Chester, Pennsylvania 19383, United States
| | - Marlene Orandle
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Naveena Yanamala
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Matthew M Dahm
- National Institute for Occupational Safety and Health , Cincinnati, Ohio 45213, United States
| | - M Eileen Birch
- National Institute for Occupational Safety and Health , Cincinnati, Ohio 45213, United States
| | - Douglas E Evans
- National Institute for Occupational Safety and Health , Cincinnati, Ohio 45213, United States
| | - Vamsi K Kodali
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Tracy Eye
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Lori Battelli
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Patti C Zeidler-Erdely
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Gary Casuccio
- RJ Lee Group , Monroeville, Pennsylvania 15146, United States
| | - Kristin Bunker
- RJ Lee Group , Monroeville, Pennsylvania 15146, United States
| | - Jason S Lupoi
- RJ Lee Group , Monroeville, Pennsylvania 15146, United States
| | - Traci L Lersch
- RJ Lee Group , Monroeville, Pennsylvania 15146, United States
| | - Aleksandr B Stefaniak
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Tina Sager
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Aliakbar Afshari
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Diane Schwegler-Berry
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Sherri Friend
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Jonathan Kang
- West Virginia University , Morgantown, West Virginia 26505, United States
| | - Katelyn J Siegrist
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Constance A Mitchell
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - David T Lowry
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Michael L Kashon
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Robert R Mercer
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Charles L Geraci
- National Institute for Occupational Safety and Health , Cincinnati, Ohio 45213, United States
| | | | - Linda M Sargent
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
| | - Aaron Erdely
- National Institute for Occupational Safety and Health , Morgantown, West Virginia 26505, United States
- West Virginia University , Morgantown, West Virginia 26505, United States
| |
Collapse
|
16
|
Ogura I, Okayama C, Kotake M, Ata S, Matsui Y, Gotoh K. Airborne particles released by crushing CNT composites. ACTA ACUST UNITED AC 2017. [DOI: 10.1088/1742-6596/838/1/012015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
17
|
Kuijpers E, Bekker C, Brouwer D, le Feber M, Fransman W. Understanding workers' exposure: Systematic review and data-analysis of emission potential for NOAA. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2017; 14:349-359. [PMID: 27801630 DOI: 10.1080/15459624.2016.1252843] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Exposure assessment for nano-objects, and their aggregates and agglomerates (NOAA), has evolved from explorative research toward more comprehensive exposure assessment, providing data to further develop currently used conservative control banding (CB) tools for risk assessment. This study aims to provide an overview of current knowledge on emission potential of NOAA across the occupational life cycle stages by a systematic review and subsequently use the results in a data analysis. Relevant parameters that influence emission were collected from peer-reviewed literature with a focus on the four source domains (SD) in the source-receptor conceptual framework for NOAA. To make the reviewed exposure data comparable, we applied an approach to normalize for workplace circumstances and measurement location, resulting in comparable "surrogate" emission levels. Finally, descriptive statistics were performed. During the synthesis of nanoparticles (SD1), mechanical reduction and gas phase synthesis resulted in the highest emission compared to wet chemistry and chemical vapor condensation. For the handling and transfer of bulk manufactured nanomaterial powders (SD2) the emission could be differentiated for five activity classes: (1) harvesting; (2) dumping; (3); mixing; (4) cleaning of a reactor; and (5) transferring. Additionally, SD2 was subdivided by the handled amount with cleaning further subdivided by energy level. Harvesting and dumping resulted in the highest emissions. Regarding processes with liquids (SD3b), it was possible to distinguish emissions for spraying (propellant gas, (high) pressure and pump), sonication and brushing/rolling. The highest emissions observed in SD3b were for propellant gas spraying and pressure spraying. The highest emissions for the handling of nano-articles (SD4) were found to nano-sized particles (including NOAA) for grinding. This study provides a valuable overview of emission assessments performed in the workplace during the occupational handling of NOAA. Analyses were made per source domain to derive emission levels which can be used for models to quantitatively predict the exposure.
Collapse
Affiliation(s)
| | - C Bekker
- a TNO , Zeist , The Netherlands
- b Institute for Risk Assessment Sciences (IRAS), Molecular Epidemiology and Risk Assessment Utrecht , Utrecht , The Netherlands
| | - D Brouwer
- a TNO , Zeist , The Netherlands
- c School of Public Health, Faculty of Health Sciences, University of the Witwatersrand Johannesburg, RSA , Johannesburg , South Africa
| | | | | |
Collapse
|
18
|
Nguyen T, Petersen EJ, Pellegrin B, Gorham JM, Lam T, Zhao M, Sung L. Impact of UV irradiation on multiwall carbon nanotubes in nanocomposites: formation of entangled surface layer and mechanisms of release resistance. CARBON 2017; 116:191-200. [PMID: 28603293 PMCID: PMC5460675 DOI: 10.1016/j.carbon.2017.01.097] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Multiwall carbon nanotubes (MWCNTs) are nanofillers used in consumer and structural polymeric products to enhance a variety of properties. Under weathering, the polymer matrix will degrade and the nanofillers may be released from the products potentially impacting ecological or human health. In this study, we investigated the degradation of a 0.72 % (by mass) MWCNT/amine-cured epoxy nanocomposite irradiated with high intensity ultraviolet (UV) light at various doses, the effects of UV exposure on the surface accumulation and potential release of MWCNTs, and possible mechanisms for the release resistance of the MWCNT surface layer formed on nanocomposites by UV irradiation. Irradiated samples were characterized for chemical degradation, mass loss, surface morphological changes, and MWCNT release using a variety of analytical techniques. Under 295 nm to 400 nm UV radiation up to a dose of 4865 MJ/m2, the nanocomposite matrix underwent photodegradation, resulting in formation of a dense, entangled MWCNT network structure on the surface. However, no MWCNT release was detected, even at very high UV doses, suggesting that the MWCNT surface layer formed from UV irradiation of polymer nanocomposites resist release. Four possible release resistance mechanisms of the UV-induced MWCNT surface layer are presented and discussed.
Collapse
Affiliation(s)
- Tinh Nguyen
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | - Elijah J Petersen
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | - Bastien Pellegrin
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | - Justin M Gorham
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | - Thomas Lam
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | - Minhua Zhao
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| | - Lipiin Sung
- National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899
| |
Collapse
|
19
|
Wang J, Schlagenhauf L, Setyan A. Transformation of the released asbestos, carbon fibers and carbon nanotubes from composite materials and the changes of their potential health impacts. J Nanobiotechnology 2017; 15:15. [PMID: 28219381 PMCID: PMC5319145 DOI: 10.1186/s12951-017-0248-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 02/10/2017] [Indexed: 12/11/2022] Open
Abstract
Composite materials with fibrous reinforcement often provide superior mechanical, thermal, electrical and optical properties than the matrix. Asbestos, carbon fibers and carbon nanotubes (CNTs) have been widely used in composites with profound impacts not only on technology and economy but also on human health and environment. A large number of studies have been dedicated to the release of fibrous particles from composites. Here we focus on the transformation of the fibrous fillers after their release, especially the change of the properties essential for the health impacts. Asbestos fibers exist in a large number of products and the end-of-the-life treatment of asbestos-containing materials poses potential risks. Thermal treatment can transform asbestos to non-hazardous phase which provides opportunities of safe disposal of asbestos-containing materials by incineration, but challenges still exist. Carbon fibers with diameters in the range of 5–10 μm are not considered to be respirable, however, during the release process from composites, the carbon fibers may be split along the fiber axis, generating smaller and respirable fibers. CNTs may be exposed on the surface of the composites or released as free standing fibers, which have lengths shorter than the original ones. CNTs have high thermal stability and may be exposed after thermal treatment of the composites and still keep their structural integrity. Due to the transformation of the fibrous fillers during the release process, their toxicity may be significantly different from the virgin fibers, which should be taken into account in the risk assessment of fiber-containing composites.
Collapse
Affiliation(s)
- Jing Wang
- Institute of Environmental Engineering, ETH Zurich, 8093, Zurich, Switzerland. .,Advanced Analytical Technologies, Empa, Ueberlandstrasse 129, 8600, Dübendorf, Switzerland.
| | - Lukas Schlagenhauf
- Institute of Environmental Engineering, ETH Zurich, 8093, Zurich, Switzerland.,Advanced Analytical Technologies, Empa, Ueberlandstrasse 129, 8600, Dübendorf, Switzerland
| | - Ari Setyan
- Institute of Environmental Engineering, ETH Zurich, 8093, Zurich, Switzerland.,Advanced Analytical Technologies, Empa, Ueberlandstrasse 129, 8600, Dübendorf, Switzerland
| |
Collapse
|
20
|
González-Gálvez D, Janer G, Vilar G, Vílchez A, Vázquez-Campos S. The Life Cycle of Engineered Nanoparticles. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 947:41-69. [PMID: 28168665 DOI: 10.1007/978-3-319-47754-1_3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The first years in the twenty-first century have meant the inclusion of nanotechnology in most industrial sectors, from very specific sensors to construction materials. The increasing use of nanomaterials in consumer products has raised concerns about their potential risks for workers, consumers and the environment. In a comprehensive risk assessment or life cycle assessment, a life cycle schema is the starting point necessary to build up the exposure scenarios and study the processes and mechanisms driving to safety concerns. This book chapter describes the processes that usually occur at all the stages of the life cycle of the nano-enabled product, from the nanomaterial synthesis to the end-of-life of the products. Furthermore, release studies reported in literature related to these processes are briefly discussed.
Collapse
Affiliation(s)
- David González-Gálvez
- LEITAT Technological Center, C/ de la Innovació 2, 08225, Terrassa (Barcelona), Spain
| | - Gemma Janer
- LEITAT Technological Center, C/ de la Innovació 2, 08225, Terrassa (Barcelona), Spain
| | - Gemma Vilar
- LEITAT Technological Center, C/ de la Innovació 2, 08225, Terrassa (Barcelona), Spain
| | - Alejandro Vílchez
- LEITAT Technological Center, C/ de la Innovació 2, 08225, Terrassa (Barcelona), Spain
| | | |
Collapse
|
21
|
Guseva Canu I, Bateson TF, Bouvard V, Debia M, Dion C, Savolainen K, Yu IJ. Human exposure to carbon-based fibrous nanomaterials: A review. Int J Hyg Environ Health 2016; 219:166-75. [PMID: 26752069 DOI: 10.1016/j.ijheh.2015.12.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 12/18/2015] [Accepted: 12/19/2015] [Indexed: 12/29/2022]
Abstract
In an emerging field of nanotechnologies, assessment of exposure to carbon nanotubes (CNT) and carbon nanofibers (CNF) is an integral component of occupational and environmental epidemiology, risk assessment and management, as well as regulatory actions. The current state of knowledge on exposure to carbon-based fibrous nanomaterials among workers, consumers and general population was studied in frame of the International Agency for Research on Cancer (IARC) Monographs-Volume 111 "Some Nanomaterials and Some Fibres". Completeness and reliability of available exposure data for use in epidemiology and risk assessment were assessed. Occupational exposure to CNT/CNF may be of concern at all stages of the material life-cycle from research through manufacture to use and disposal. Consumer and environmental exposures are only estimated by modeled data. The available information of the final steps of the life-cycle of these materials remains incomplete so far regarding amounts of handled materials and levels of exposure. The quality and amount of information available on the uses and applications of CNT/CNF should be improved to enable quantitative assessment of human exposure to these materials. For that, coordinated effort in producing surveys and exposure inventories based on harmonized strategy of material test, exposure measurement and reporting results is strongly encouraged.
Collapse
Affiliation(s)
- Irina Guseva Canu
- Institut de veille sanitaire, Département Santé-Travail, Saint-Maurice, France.
| | - Thomas F Bateson
- Environmental Protection Agency, Effects Identification & Characterization Group, Washington, DC, USA
| | - Veronique Bouvard
- International Agency for Research on Cancer (IARC), IARC Monographs Section, Lyon, France
| | - Maximilien Debia
- Institut de recherche en santé publique de l'Université de Montréal, Département de santé environnementale et santé au travail, Montreal, Canada
| | - Chantal Dion
- Institut de recherche en santé publique de l'Université de Montréal, Département de santé environnementale et santé au travail, Montreal, Canada; Institut de recherche Robert-Sauvé en santé et sécurité du travail, Département de santé environnementale et santé au travail, Montreal, Canada
| | - Kai Savolainen
- Finnish Institute of Occupational Health, Nanosafety Research Centre, Helsinki, Finland
| | - Il-Je Yu
- Hoseo University, Toxicological Research Center, Asan, South Korea
| |
Collapse
|
22
|
Schlagenhauf L, Kianfar B, Buerki-Thurnherr T, Kuo YY, Wichser A, Nüesch F, Wick P, Wang J. Weathering of a carbon nanotube/epoxy nanocomposite under UV light and in water bath: impact on abraded particles. NANOSCALE 2015; 7:18524-18536. [PMID: 26490158 DOI: 10.1039/c5nr05387k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Weathering processes can influence the surface properties of composites with incorporated nanoparticles. These changes may affect the release behavior of nanoparticles when an abrasion process is applied. Therefore, the influence of two different weathering processes, immersion in water and exposure to UV light, on the properties of abraded particles from a carbon nanotube (CNT)/epoxy nanocomposite was investigated. The investigation included the measurement of the weathering impact on the surface chemistry of the exposed samples, the particle size of abraded particles, the quantity of exposed CNTs in the respirable part of the abraded particles, and the toxicity of abraded particles, measured by in vitro toxicity tests using the THP-1 monocyte-derived macrophages. The results showed that weathering by immersion in water had no influence on the properties of abraded particles. The exposure to UV light caused a degradation of the epoxy on the surface, followed by delamination of an approx. 2.5 μm thick layer. An increased quantity of exposed CNTs in abraded particles was not found; on the contrary, longer UV exposure times decreased the released fraction of CNTs from 0.6% to 0.4%. The toxicity tests revealed that abraded particles from the nanocomposites did not induce additional acute cytotoxic effects compared to particles from the neat epoxy.
Collapse
Affiliation(s)
- Lukas Schlagenhauf
- Laboratory for Functional Polymers, Empa - Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Christou A, Stec AA, Ahmed W, Aschberger K, Amenta V. A review of exposure and toxicological aspects of carbon nanotubes, and as additives to fire retardants in polymers. Crit Rev Toxicol 2015; 46:74-95. [PMID: 26482549 DOI: 10.3109/10408444.2015.1082972] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Carbon nanotubes (CNTs) have attracted considerable interest due to their unique physical, chemical, optical and electrical properties opening avenues for a large number of industrial applications. They have shown potential as fire retardant additives in polymers, reducing heat release rate and increasing time to ignition in a number of polymers. Relevant work on the types, properties and applications has been reviewed particularly considering their application in fire situations. There are concerns over the health risks associated with CNTs and many papers have likened CNTs to the health problems associated with asbestos. There are contradictions relating to the toxicity of CNTs with some papers reporting that they are toxic while others state the opposite. Directly comparing various studies is difficult because CNTs come in many combinations of size, type, purity levels and source. CNTs can potentially be released from polymers during the combustion process where human exposure may occur. While this review has shed some light regarding issues relating to toxicity under different fire scenarios much more thorough work is needed to investigate toxicity of CNTs and their evolution from CNT-polymer nanocomposites in order to reach firm conclusions.
Collapse
Affiliation(s)
- Antonis Christou
- a Centre for Fire and Hazards Sciences, University of Central Lancashire , Preston , UK
| | - Anna A Stec
- a Centre for Fire and Hazards Sciences, University of Central Lancashire , Preston , UK
| | - Waqar Ahmed
- b School of Medicine, College of Clinical and Biomedical Sciences, University of Central Lancashire , Preston , UK
| | - Karin Aschberger
- c Nanobiosciences Unit, European Commission - DG Joint Research Centre, Institute for Health and Consumer Protection , Ispra , Italy , and
| | - Valeria Amenta
- d European Chemical Agency , Annankatu 18 , Helsinki , Finland
| |
Collapse
|
24
|
Thompson D, Chen SC, Wang J, Pui DYH. Aerosol Emission Monitoring and Assessment of Potential Exposure to Multi-walled Carbon Nanotubes in the Manufacture of Polymer Nanocomposites. ANNALS OF OCCUPATIONAL HYGIENE 2015. [PMID: 26209597 DOI: 10.1093/annhyg/mev044] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Recent animal studies have shown that carbon nanotubes (CNTs) may pose a significant health risk to those exposed in the workplace. To further understand this potential risk, effort must be taken to measure the occupational exposure to CNTs. Results from an assessment of potential exposure to multi-walled carbon nanotubes (MWCNTs) conducted at an industrial facility where polymer nanocomposites were manufactured by an extrusion process are presented. Exposure to MWCNTs was quantified by the thermal-optical analysis for elemental carbon (EC) of respirable dust collected by personal sampling. All personal respirable samples collected (n = 8) had estimated 8-h time weighted average (TWA) EC concentrations below the limit of detection for the analysis which was about one-half of the recommended exposure limit for CNTs, 1 µg EC/m(3) as an 8-h TWA respirable mass concentration. Potential exposure sources were identified and characterized by direct-reading instruments and area sampling. Area samples analyzed for EC yielded quantifiable mass concentrations inside an enclosure where unbound MWCNTs were handled and near a pelletizer where nanocomposite was cut, while those analyzed by electron microscopy detected the presence of MWCNTs at six locations throughout the facility. Through size selective area sampling it was identified that the airborne MWCNTs present in the workplace were in the form of large agglomerates. This was confirmed by electron microscopy where most of the MWCNT structures observed were in the form of micrometer-sized ropey agglomerates. However, a small fraction of single, free MWCNTs was also observed. It was found that the high number concentrations of nanoparticles, ~200000 particles/cm(3), present in the manufacturing facility were likely attributable to polymer fumes produced in the extrusion process.
Collapse
Affiliation(s)
- Drew Thompson
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sheng-Chieh Chen
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jing Wang
- Institute of Environmental Engineering, ETH Zurich, 8093 Zurich, Switzerland; Department of Analytical Chemistry, Empa, 8600 Dubendorf, Switzerland
| | - David Y H Pui
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN 55455, USA; Faculty of Science, The University of Hong Kong, Pokfulam, Hong Kong
| |
Collapse
|
25
|
Harper S, Wohlleben W, Doa M, Nowack B, Clancy S, Canady R, Maynard A. Measuring Nanomaterial Release from Carbon Nanotube Composites: Review of the State of the Science. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/1742-6596/617/1/012026] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
26
|
Bekker C, Kuijpers E, Brouwer DH, Vermeulen R, Fransman W. Occupational Exposure to Nano-Objects and Their Agglomerates and Aggregates Across Various Life Cycle Stages; A Broad-Scale Exposure Study. ANNALS OF OCCUPATIONAL HYGIENE 2015; 59:681-704. [PMID: 25846362 DOI: 10.1093/annhyg/mev023] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/18/2015] [Indexed: 12/30/2022]
Abstract
BACKGROUND Occupational exposure to manufactured nano-objects and their agglomerates, and aggregates (NOAA) has been described in several workplace air monitoring studies. However, data pooling for general conclusions and exposure estimates are hampered by limited exposure data across the occupational life cycle of NOAA and a lack in comparability between the methods of collecting and analysing the data. By applying a consistent method of collecting and analysing the workplace exposure data, this study aimed to provide information about the occupational NOAA exposure levels across various life cycle stages of NOAA in the Netherlands which can also be used for multi-purpose use. METHODS Personal/near field task-based exposure data was collected using a multi-source exposure assessment method collecting real time particle number concentration, particle size distribution (PSD), filter-based samples for morphological, and elemental analysis and detailed contextual information. A decision logic was followed allowing a consistent and objective way of analysing the exposure data. RESULTS In total, 46 measurement surveys were conducted at 15 companies covering 18 different exposure situations across various occupational life cycle stages of NOAA. Highest activity-effect levels were found during replacement of big bags (<1000-76000 # cm(-3)), mixing/dumping of powders manually (<1000-52000 # cm(-3)) and mechanically (<1000-100000 # cm(-3)), and spraying of liquid (2000-800000 # cm(-3)) showing a high variability between and within the various exposure situations. In general, a limited change in PSD was found during the activity compared to the background. CONCLUSIONS This broad-scale exposure study gives a comprehensive overview of the NOAA exposure situations in the Netherlands and an indication of the levels of occupational exposure to NOAA across various life cycle of NOAA. The collected workplace exposure data and contextual information will serve as basis for future pooling of data and modelling of worker exposure.
Collapse
Affiliation(s)
- Cindy Bekker
- 1.Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, the Netherlands 2.TNO, Utrechtseweg 48, 3704 HE, Zeist, the Netherlands
| | | | | | - Roel Vermeulen
- 1.Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, the Netherlands
| | | |
Collapse
|
27
|
Duncan TV. Release of engineered nanomaterials from polymer nanocomposites: the effect of matrix degradation. ACS APPLIED MATERIALS & INTERFACES 2015; 7:20-39. [PMID: 25397693 DOI: 10.1021/am5062757] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Polymer nanocomposites-polymer-based materials that incorporate filler elements possessing at least one dimension in the nanometer range-are increasingly being developed for commercial applications ranging from building infrastructure to food packaging to biomedical devices and implants. Despite a wide range of intended applications, it is also important to understand the potential for exposure to these nanofillers, which could be released during routine use or abuse of these materials so that it can be determined whether they pose a risk to human health or the environment. This article is the second of a pair that review what is known about the release of engineered nanomaterials (ENMs) from polymer nanocomposites. Two roughly separate ENM release paradigms are considered in this series: the release of ENMs via passive diffusion, desorption, and dissolution into external liquid media and the release of ENMs assisted by matrix degradation. The present article is focused primarily on the second paradigm and includes a thorough, critical review of the associated body of peer-reviewed literature on ENM release by matrix degradation mechanisms, including photodegradation, thermal decomposition, mechanical wear, and hydrolysis. These release mechanisms may be especially relevant to nanocomposites that are likely to be subjected to weathering, including construction and infrastructural materials, sporting equipment, and materials that might potentially end up in landfills. This review pays particular attention to studies that shed light on specific release mechanisms and synergistic mechanistic relationships. The review concludes with a short section on knowledge gaps and future research needs.
Collapse
Affiliation(s)
- Timothy V Duncan
- Center for Food Safety and Applied Nutrition, United States Food and Drug Administration , 6502 South Archer Road, Bedford Park, Illinois 60501, United States
| |
Collapse
|
28
|
A review and perspective of existing research on the release of nanomaterials from solid nanocomposites. Part Fibre Toxicol 2014; 11:17. [PMID: 24708765 PMCID: PMC4023549 DOI: 10.1186/1743-8977-11-17] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 02/28/2014] [Indexed: 12/14/2022] Open
Abstract
Advances in adding nanomaterials to various matrices have occurred in tandem with the identification of potential hazards associated with exposure to pure forms of nanomaterials. We searched multiple research publication databases and found that, relative to data generated on potential nanomaterial hazards or exposures, very little attention has focused on understanding the potential and conditions for release of nanomaterials from nanocomposites. However, as a prerequisite to exposure studying release is necessary to inform risk assessments. We identified fifty-four studies that specifically investigated the release of nanomaterials, and review them in the following release scenario groupings: machining, weathering, washing, contact and incineration. While all of the identified studies provided useful information, only half were controlled experiments. Based on these data, the debris released from solid, non-food nanocomposites contains in varying frequencies, a mixture of four types of debris. Most frequently identified are (1) particles of matrix alone, and slightly less often, the (2) matrix particles exhibit the nanomaterial partially or fully embedded; far less frequently is (3) the added nanomaterial entirely dissociated from the matrix identified: and most rare are (4) dissolved ionic forms of the added nanomaterial. The occurrence of specific debris types appeared to be dependent on the specific release scenario and environment. These data highlight that release from nanocomposites can take multiple forms and that additional research and guidance would be beneficial, allowing for more consistent characterization of the release potential of nanomaterials. In addition, these data support calls for method validation and standardization, as well as understanding how laboratory release scenarios relate to real-world conditions. Importantly, as risk is considered to be a function of the inherent hazards of a substance and the actual potential for exposure, data on nanomaterial release dynamics and debris composition from commercially relevant nanocomposites are a valuable starting point for consideration in fate and transport modeling, exposure assessment, and risk assessment frameworks for nanomaterials.
Collapse
|
29
|
|
30
|
Hirth S, Cena L, Cox G, Tomović Ž, Peters T, Wohlleben W. Scenarios and methods that induce protruding or released CNTs after degradation of nanocomposite materials. JOURNAL OF NANOPARTICLE RESEARCH : AN INTERDISCIPLINARY FORUM FOR NANOSCALE SCIENCE AND TECHNOLOGY 2013; 15:1504. [PMID: 23596358 PMCID: PMC3625415 DOI: 10.1007/s11051-013-1504-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2012] [Accepted: 02/10/2013] [Indexed: 05/21/2023]
Abstract
ABSTRACT Nanocomposite materials may be considered as a low-risk application of nanotechnology, if the nanofillers remain embedded throughout the life-cycle of the products in which they are embedded. We hypothesize that release of free CNTs occurs by a combination of mechanical stress and chemical degradation of the polymer matrix. We experimentally address limiting cases: Mechanically released fragments may show tubular protrusions on their surface. Here we identify these protrusions unambiguously as naked CNTs by chemically resolved microscopy and a suitable preparation protocol. By size-selective quantification of fragments we establish as a lower limit that at least 95 % of the CNTs remain embedded. Contrary to classical fiber composite approaches, we link this phenomenon to matrix materials with only a few percent elongation at break, predicting which materials should still cover their CNT nanofillers after machining. Protruding networks of CNTs remain after photochemical degradation of the matrix, and we show that it takes the worst case combinations of weathering plus high-shear wear to release free CNTs in the order of mg/m2/year. Synergy of chemical degradation and mechanical energy input is identified as the priority scenario of CNT release, but its lab simulation by combined methods is still far from real-world validation.
Collapse
Affiliation(s)
| | | | | | - Željko Tomović
- BASF Polyurethanes GmbH, GMU/UE, Elastogranstrasse 60, 49448 Lemfoerde, Germany
| | | | | |
Collapse
|