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Chen G, Song Y, Zhang H, Sun Y, Zeng D, Cheng Z, Yan B. Characteristics of pollutant generation from 3D-printed photocured waste combustion. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 187:61-69. [PMID: 38996620 DOI: 10.1016/j.wasman.2024.07.010] [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: 03/11/2024] [Revised: 06/12/2024] [Accepted: 07/05/2024] [Indexed: 07/14/2024]
Abstract
With the rapid advancement of photopolymerization-based 3D printing technology, the volume of PCW has experienced a sharp increase. The potential environmental ramifications of PCW disposal demand careful consideration, especially given its current practice of being incineration alongside MSW. In this study, the TG-MS/FTIR system was carried out to probe the thermogravimetric characteristics and volatile byproducts during combustion. Various product compositions resulting from different mixing ratios of PCW incineration with MSW were investigated. It was observed that fluorene (C13H10) and triphenylene (C18H12) produced by PCW combustion 0.52 mg/g and 0.43 mg/g respectively, which are twice as abundant as those generated from normal plastic. When PCW incineration along with MSW, compounds such as naphthalene (C10H8), cyclohexane (C6H12), and heptane (C7H16) were generated in concentrations of 1.25 mg/g, 1.05 mg/g, and 0.95 mg/g respectively, which are at least twice as much as with MSW incineration alone. The incineration of PCW with rubber and textiles resulted in the production of 2.34 mg/g to 3.76 mg/g more PAHs compared to PCW combustion alone. The incineration of PCW with paper resulted in the production of 3.12 mg/g to 5.15 mg/g more heptane, nonane, cyclohexane, pyrene, and anthracene than PCW combustion alone. Incineration of PCW with wood proved to be the cleanest method, with product contents primarily below 0.10 mg/g. When incinerated with food residues or normal plastic, most of the product content remained below 0.05 mg/g. Considering the environmental pollution resulting from PCW combustion, the disposal of PCW warrants careful consideration and management.
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Affiliation(s)
- Guanyi Chen
- School of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134, China; School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China; School of ecology and environment, Tibet University, Tibet 850012, China
| | - Yuru Song
- School of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134, China
| | - Hongnan Zhang
- School of ecology and environment, Tibet University, Tibet 850012, China
| | - Yunan Sun
- School of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134, China.
| | - Dan Zeng
- School of ecology and environment, Tibet University, Tibet 850012, China
| | - Zhanjun Cheng
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China; Engineering Research Center for Organic Wastes Safe Disposal and Energy Utilization, Tianjin 300072, China
| | - Beibei Yan
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China; Tianjin Key Lab of Biomass Wastes Utilization/Tianjin Engineering Research Center of Bio Gas/Oil Technology, Tianjin 300072, China
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Minář J, Pilnaj D, Uřičář J, Veselý P, Dušek K. Application of solid-phase microextraction arrows for characterizing volatile organic compounds from 3D printing of acrylonitrile-styrene-acrylate filament. J Chromatogr A 2023; 1705:464180. [PMID: 37393779 DOI: 10.1016/j.chroma.2023.464180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/28/2023] [Accepted: 06/25/2023] [Indexed: 07/04/2023]
Abstract
3D printing is an extensively used manufacturing technique that can pose specific health concerns due to the emission of volatile organic compounds (VOC). Herein, a detailed characterization of 3D printing-related VOC using solid-phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) is described for the first time. The VOC were extracted in dynamic mode during the printing from the acrylonitrile-styrene-acrylate filament in an environmental chamber. The effect of extraction time on the extraction efficiency of 16 main VOC was studied for four different commercial SPME arrows. The volatile and semivolatile compounds were the most effectively extracted by carbon wide range-containing and polydimethyl siloxane arrows, respectively. The differences in extraction efficiency between arrows were further correlated to the molecular volume, octanol-water partition coefficient, and vapour pressure of observed VOC. The repeatability of SPME arrows towards the main VOC was assessed from static mode measurements of filament in headspace vials. In addition, we performed a group analysis of 57 VOC classified into 15 categories according to their chemical structure. Divinylbenzene-polydimethyl siloxane arrow turned out to be a good compromise between the total extracted amount and its distribution among tested VOC. Thus, this arrow was used to demonstrate the usefulness of SPME for the qualification of VOC emitted during printing in a real-life environment. A presented methodology can serve as a fast and reliable method for the qualification and semi-quantification of 3D printing-related VOC.
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Affiliation(s)
- Jaroslav Minář
- Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague 160 00, Czech Republic.
| | - Dominik Pilnaj
- Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague 160 00, Czech Republic; Department of Environmental Chemistry and Technology, Faculty of Environment, Jan Evangelista Purkyně University, Ústí nad Labem 400 96, Czech Republic
| | - Jonáš Uřičář
- Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague 160 00, Czech Republic
| | - Petr Veselý
- Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague 160 00, Czech Republic
| | - Karel Dušek
- Department of Electrotechnology, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague 160 00, Czech Republic
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Moazami TN, Svendsen KVH, Buhagen M, Jørgensen RB. Comparing PM 2.5, respirable dust, and total dust fractions using real-time and gravimetric samples in an exposure chamber study. Heliyon 2023; 9:e16127. [PMID: 37274722 PMCID: PMC10238574 DOI: 10.1016/j.heliyon.2023.e16127] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 04/21/2023] [Accepted: 05/06/2023] [Indexed: 06/06/2023] Open
Abstract
Using an exposure chamber, we investigate the precision of the DustTrak DRX monitor by comparing its results to those obtained from taking traditional gravimetric samples of two stone minerals commonly used in asphalt and lactose powder. We also discuss the possibility of using real-time monitors such as DustTrak DRX for occupational exposure monitoring purposes. The results are based on 19 days of experiment, each day with measurements collected over 4 h. Compared to the gravimetric samples, the DustTrak DRX overestimated the PM2.5 and respirable dust concentrations, while it underestimated the total dust concentration by a factor of nearly two. However, the ratios, being done for more than one material, between the DustTrak DRX and the gravimetric sample readings varied daily and across the different exposure materials. Real-time sensors have the potential to excel at identifying exposure sources, evaluating the measured control efficiency, visualizing variations in exposure to motivate workers, and contributing to the identification of measures to be implemented to reduce exposure. For total dust, a correction factor of at least two should be used to bring its readings up to those for the corresponding gravimetric samples. Also, if the DustTrak DRX is used in the initial profiling of occupational exposure, the exposure could be considered acceptable if the readings are well below the occupational exposure limit (OELs) after correction. If the DustTrak DRX readings, after correction, is close to, or above, the accepted exposure concentrations, more thorough approaches would be required to validate the exposure.
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Affiliation(s)
- Therese Nitter Moazami
- Department of Industrial Economics and Technology Management (IØT), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Kristin v Hirsch Svendsen
- Department of Industrial Economics and Technology Management (IØT), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Morten Buhagen
- Department of Occupational Medicine, St. Olav's University Hospital, 7006, Trondheim, Norway
| | - Rikke Bramming Jørgensen
- Department of Industrial Economics and Technology Management (IØT), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
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Pham YL, Wojnowski W, Beauchamp J. Volatile Compound Emissions from Stereolithography Three-Dimensional Printed Cured Resin Models for Biomedical Applications. Chem Res Toxicol 2023; 36:369-379. [PMID: 36534374 DOI: 10.1021/acs.chemrestox.2c00317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Stereolithography three-dimensional printing is used increasingly in biomedical applications to create components for use in healthcare and therapy. The exposure of patients to volatile organic compounds (VOCs) emitted from cured resins represents an element of concern in such applications. Here, we investigate the biocompatibility in relation to inhalation exposure of volatile emissions of three different cured commercial resins for use in printing a mouthpiece adapter for sampling exhaled breath. VOC emission rates were estimated based on direct analysis using a microchamber/thermal extractor coupled to a proton transfer reaction-mass spectrometer. Complementary analyses using comprehensive gas chromatography-mass spectrometry aided compound identification. Major VOCs emitted from the cured resins were associated with polymerization agents, additives, and postprocessing procedures and included alcohols, aldehydes, ketones, hydrocarbons, esters, and terpenes. Total VOC emissions from cubes printed using the general-purpose resin were approximately an order of magnitude higher than those of the cubes printed using resins dedicated to biomedical applications at the respective test temperatures (40 and 25 °C). Daily inhalation exposures were estimated and compared with daily tolerable intake levels or standard thresholds of toxicological concerns. The two resins intended for biomedical applications were deemed suitable for fabricating an adapter mouthpiece for use in breath research. The general-purpose resin was unsuitable, with daily inhalation exposures for breath sampling applications at 40 °C estimated at 310 μg day-1 for propylene glycol (tolerable intake (TI) limit of 190 μg day-1) and 1254 μg day-1 for methyl acrylate (TI of 43 μg day-1).
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Affiliation(s)
- Y Lan Pham
- Department of Sensory Analytics and Technologies, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354Freising, Germany
- Department of Chemistry and Pharmacy, Chair of Aroma and Smell Research, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 9, 91054Erlangen, Germany
| | - Wojciech Wojnowski
- Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 Narutowicza Street, 80-233Gdańsk, Poland
- Department of Chemistry, University of Oslo, P.O. Box 1033-Blindern, 0315Oslo, Norway
| | - Jonathan Beauchamp
- Department of Sensory Analytics and Technologies, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354Freising, Germany
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Almstrand AC, Bredberg A, Runström Eden G, Karlsson H, Assenhöj M, Koca H, Olin AC, Tinnerberg H. An explorative study on respiratory health among operators working in polymer additive manufacturing. Front Public Health 2023; 11:1148974. [PMID: 37151597 PMCID: PMC10155750 DOI: 10.3389/fpubh.2023.1148974] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/13/2023] [Indexed: 05/09/2023] Open
Abstract
Additive manufacturing (AM), or 3D printing, is a growing industry involving a wide range of different techniques and materials. The potential toxicological effects of emissions produced in the process, involving both ultrafine particles and volatile organic compounds (VOCs), are unclear, and there are concerns regarding possible health implications among AM operators. The objective of this study was to screen the presence of respiratory health effects among people working with liquid, powdered, or filament plastic materials in AM. Methods In total, 18 subjects working with different additive manufacturing techniques and production of filament with polymer feedstock and 20 controls participated in the study. Study subjects filled out a questionnaire and underwent blood and urine sampling, spirometry, impulse oscillometry (IOS), exhaled NO test (FeNO), and collection of particles in exhaled air (PEx), and the exposure was assessed. Analysis of exhaled particles included lung surfactant components such as surfactant protein A (SP-A) and phosphatidylcholines. SP-A and albumin were determined using ELISA. Using reversed-phase liquid chromatography and targeted mass spectrometry, the relative abundance of 15 species of phosphatidylcholine (PC) was determined in exhaled particles. The results were evaluated by univariate and multivariate statistical analyses (principal component analysis). Results Exposure and emission measurements in AM settings revealed a large variation in particle and VOC concentrations as well as the composition of VOCs, depending on the AM technique and feedstock. Levels of FeNO, IOS, and spirometry parameters were within clinical reference values for all AM operators. There was a difference in the relative abundance of saturated, notably dipalmitoylphosphatidylcholine (PC16:0_16:0), and unsaturated lung surfactant lipids in exhaled particles between controls and AM operators. Conclusion There were no statistically significant differences between AM operators and controls for the different health examinations, which may be due to the low number of participants. However, the observed difference in the PC lipid profile in exhaled particles indicates a possible impact of the exposure and could be used as possible early biomarkers of adverse effects in the airways.
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Affiliation(s)
- Ann-Charlotte Almstrand
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
- Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
- *Correspondence: Ann-Charlotte Almstrand,
| | - Anna Bredberg
- RISE, Research Institutes of Sweden, Gothenburg, Sweden
| | - Gunilla Runström Eden
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
- Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Helen Karlsson
- Occupational and Environmental Medicine Center in Linköping, and Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Maria Assenhöj
- Occupational and Environmental Medicine Center in Linköping, and Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Hatice Koca
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
- Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Anna-Carin Olin
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
- Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Håkan Tinnerberg
- Occupational and Environmental Medicine, School of Public Health and Community Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
- Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
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6
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Pham YL, Wojnowski W, Beauchamp J. Online Volatile Compound Emissions Analysis Using a Microchamber/Thermal Extractor Coupled to Proton Transfer Reaction-Mass Spectrometry. Anal Chem 2022; 94:17354-17359. [PMID: 36481090 PMCID: PMC9773172 DOI: 10.1021/acs.analchem.2c03454] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Indoor air is a complex and dynamic mixture comprising manifold volatile organic compounds (VOCs) that may cause physiological and/or psychological discomfort, depending on the nature of exposure. This technical note presents a novel approach to analyze VOC emissions by coupling a microchamber/thermal extractor (μ-CTE) system to a proton transfer reaction-mass spectrometer (PTR-MS). This configuration provides an alternative to conventional emissions testing of small objects. The dynamic emission profiles of VOCs from a representative 3D-printed model are presented as a proof-of-concept analysis. Emission profiles are related to the target compound volatility, whereby 2-propanol and acetaldehyde exhibited the highest emissions and most rapid changes compared to the less volatile vinyl crotonate, 2-hydroxymethyl methacrylate, and mesitaldehyde, which were present at lower concentrations and showed different dynamics. Comparative measurements of the emission profiles of these compounds either with or without prior static equilibration yielded stark differences in their dynamics, albeit converging to similar values after 15 min of sampling time. Further, the utility of this system to determine the time required to capture a specific proportion of volatile emissions over the sampling period was demonstrated, with a mean duration of 8.4 ± 0.3 min to sample 50% of emissions across all compounds. This novel configuration provides a means to characterize the dynamic nature of VOC emissions from small objects and is especially suited to measuring highly volatile compounds, which can present a challenge for conventional sampling and analysis approaches. Further, it represents an opportunity for rapid, targeted emissions analyses of products to screen for potentially harmful volatiles.
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Affiliation(s)
- Y Lan Pham
- Department
of Sensory Analytics and Technologies, Fraunhofer
Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354 Freising, Germany,Department
of Chemistry and Pharmacy, Chair of Aroma and Smell Research, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 9, 91054 Erlangen, Germany
| | - Wojciech Wojnowski
- Department
of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, 11/12 Narutowicza Street, 80-233 Gdańsk, Poland,Department
of Chemistry, University of Oslo, P.O. Box 1033-Blindern, 0315 Oslo, Norway
| | - Jonathan Beauchamp
- Department
of Sensory Analytics and Technologies, Fraunhofer
Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354 Freising, Germany,
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Sheehan MJ, Vosburgh DJH, O'Shaughnessy PT, Park JH, Sotelo C. Direct-reading instruments for aerosols: A review for occupational health and safety professionals part 2: Applications. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2022; 19:706-729. [PMID: 36197433 DOI: 10.1080/15459624.2022.2132256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Direct reading instruments (DRIs) for aerosols have been used in industrial hygiene practice for many years, but their potential has not been fully realized by many occupational health and safety professionals. Although some DRIs quantify other metrics, this article will primarily focus on DRIs that measure aerosol number, size, or mass. This review addresses three applications of aerosol DRIs that occupational health and safety professionals can use to discern, characterize, and document exposure conditions and resolve aerosol-related problems in the workplace. The most common application of aerosol DRIs is the evaluation of engineering controls. Examples are provided for many types of workplaces and situations including construction, agriculture, mining, conventional manufacturing, advanced manufacturing (nanoparticle technology and additive manufacturing), and non-industrial sites. Aerosol DRIs can help identify the effectiveness of existing controls and, as needed, develop new strategies to reduce potential aerosol exposures. Aerosol concentration mapping (ACM) using DRI data can focus attention on emission sources in the workplace spatially illustrate the effectiveness of controls and constructively convey concerns to management and workers. Examples and good practices of ACM are included. Video Exposure Monitoring (VEM) is another useful technique in which video photography is synced with the concentration output of an aerosol DRI. This combination allows the occupational health and safety professional to see what tasks, environmental situations, and/or worker actions contribute to aerosol concentration and potential exposure. VEM can help identify factors responsible for temporal variations in concentration. VEM can assist with training, engage workers, convince managers about necessary remedial actions, and provide for continuous improvement of the workplace environment. Although using DRIs for control evaluation, ACM and VEM can be time-consuming, the resulting information can provide useful data to prompt needed action by employers and employees. Other barriers to adoption include privacy and security issues in some worksites. This review seeks to provide information so occupational health and safety professionals can better understand and effectively use these powerful applications of aerosol DRIs.
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Affiliation(s)
- Maura J Sheehan
- Department of Health, West Chester University, West Chester, Pennsylvania
| | - Donna J H Vosburgh
- Department of Occupational & Environmental Safety & Health, University of Wisconsin-Whitewater, Whitewater, Wisconsin
| | | | - Jae Hong Park
- School of Health Sciences, Purdue University, West Lafayette, Indiana
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Bowers LN, Stefaniak AB, Knepp AK, LeBouf RF, Martin SB, Ranpara AC, Burns DA, Virji MA. Potential for Exposure to Particles and Gases throughout Vat Photopolymerization Additive Manufacturing Processes. BUILDINGS (BASEL, SWITZERLAND) 2022; 12:10.3390/buildings12081222. [PMID: 37961074 PMCID: PMC10641710 DOI: 10.3390/buildings12081222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Vat photopolymerization (VP), a type of additive manufacturing process that cures resin to build objects, can emit potentially hazardous particles and gases. We evaluated two VP technologies, stereolithography (SLA) and digital light processing (DLP), in three separate environmental chambers to understand task-based impacts on indoor air quality. Airborne particles, total volatile organic compounds (TVOCs), and/or specific volatile organic compounds (VOCs) were monitored during each task to evaluate their exposure potential. Regardless of duration, all tasks released particles and organic gases, though concentrations varied between SLA and DLP processes and among tasks. Maximum particle concentrations reached 1200 #/cm3 and some aerosols contained potentially hazardous elements such as barium, chromium, and manganese. TVOC concentrations were highest for the isopropyl alcohol (IPA) rinsing, soaking, and drying post-processing tasks (up to 36.8 mg/m3), lowest for the resin pouring pre-printing, printing, and resin recovery post-printing tasks (up to 0.1 mg/m3), and intermediate for the curing post-processing task (up to 3 mg/m3). Individual VOCs included, among others, the potential occupational carcinogen acetaldehyde and the immune sensitizer 2-hydroxypropyl methacrylate (pouring, printing, recovery, and curing tasks). Careful consideration of all tasks is important for the development of strategies to minimize indoor air pollution and exposure potential from VP processes.
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Affiliation(s)
- Lauren N. Bowers
- National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | | | - Alycia K. Knepp
- National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - Ryan F. LeBouf
- National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - Stephen B. Martin
- National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - Anand C. Ranpara
- National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - Dru A. Burns
- National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
| | - M. Abbas Virji
- National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA
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Väisänen A, Alonen L, Ylönen S, Hyttinen M. Volatile organic compound and particulate emissions from the production and use of thermoplastic biocomposite 3D printing filaments. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2022; 19:381-393. [PMID: 35404756 DOI: 10.1080/15459624.2022.2063879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Biocomposites (BCs) can be used as substitutes for unsustainable polymers in 3D printing, but their safety demands additional investigation as biological fillers may produce altered emissions during thermal processing. Commercial filament extruders can be used to produce custom feedstocks, but they are another source of airborne contaminants and demand further research. These knowledge gaps are targeted in this study. Volatile organic compound (VOC), carbonyl compound, ultrafine particle (UFP), and fine (PM2.5) and coarse (PM10) particle air concentrations were measured in this study as a filament extruder and a 3D printer were operated under an office environment using one PLA and four PLA-based BC feedstocks. Estimates of emission rates (ERs) for total VOCs (TVOC) and UFPs were also calculated. VOCs were analyzed with a GC-MS system, carbonyls were analyzed with an LC-MS/MS system, whereas real-time particle concentrations were monitored with continuously operating instruments. VOC concentrations were low throughout the experiment; TVOC ranged between 34-63 µg/m3 during filament extrusion and 41-56 µg/m3 during 3D printing, which represent calculated TVOC ERs of 2.6‒3.6 × 102 and 2.9‒3.6 × 102 µg/min. Corresponding cumulative carbonyls ranged between 60-91 and 190-253 µg/m3. Lactide and miscellaneous acids and alcohols were the dominant VOCs, while acetone, 2-butanone, and formaldehyde were the dominant carbonyls. Terpenes contributed for ca. 20-40% of TVOC during BC processing. The average UFP levels produced by the filament extruder were 0.85 × 102-1.05 × 103 #/cm3, while the 3D printer generated 6.05 × 102-2.09 × 103 #/cm3 particle levels. Corresponding particle ERs were 5.3 × 108-6.6 × 109 and 3.8 × 109-1.3 × 1010 #/min. PM2.5 and PM10 particles were produced in the following average quantities; PM2.5 levels ranged between 0.2-2.2 µg/m3, while PM10 levels were between 5-20 µg/m3 for all materials. The main difference between the pure PLA and BC feedstock emissions was terpenes, present during all BC extrusion processes. BCs are similar emission sources as pure plastics based on our findings, and a filament extruder produces contaminants at comparable or slightly lower levels in comparison to 3D printers.
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Affiliation(s)
- Antti Väisänen
- Faculty of Science and Forestry, Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Lauri Alonen
- School of Engineering and Technology, Savonia University of Applied Sciences, Kuopio, Finland
| | - Sampsa Ylönen
- School of Engineering and Technology, Savonia University of Applied Sciences, Kuopio, Finland
| | - Marko Hyttinen
- Faculty of Science and Forestry, Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
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10
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Bowers LN, Ranpara AC, Roach KA, Knepp AK, Arnold ED, Stefaniak AB, Virji MA. Comparison of product safety data sheet ingredient lists with skin irritants and sensitizers present in a convenience sample of light-curing resins used in additive manufacturing. Regul Toxicol Pharmacol 2022; 133:105198. [PMID: 35659913 PMCID: PMC9351547 DOI: 10.1016/j.yrtph.2022.105198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 11/25/2022]
Abstract
Material jetting and vat photopolymerization additive manufacturing (AM) processes use liquid resins to build objects. These resins can contain skin irritants and/or sensitizers but product safety data sheets (SDSs) might not declare all ingredients. We characterized elemental and organic skin irritants and sensitizers present in 39 commercial products; evaluated the influence of resin manufacturer, system, color, and AM process type on the presence of irritants and sensitizers; and compared product SDSs to results. Among all products, analyses identified 23 irritant elements, 54 irritant organic substances, 22 sensitizing elements, and 23 sensitizing organic substances; SDSs listed 3, 9, 4, and 6 of these ingredients, respectively. Per product, the number and total mass (an indicator of potential dermal loading) of ingredients varied: five to 17 irritant elements (8.32-4756.65 mg/kg), one to 17 irritant organics (3273 to 356,000 mg/kg), four to 17 sensitizing elements (8.27-4755.63 mg/kg), and one to seven sensitizing organics (15-382,170 mg/kg). Median numbers and concentrations of irritants and sensitizers were significantly influenced by resin system and AM process type. The presence of undeclared irritants and sensitizers in these resins supports the need for more complete information on product SDSs for comprehensive dermal risk assessments.
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Affiliation(s)
- Lauren N Bowers
- National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV, 26505, USA
| | - Anand C Ranpara
- National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV, 26505, USA
| | - Katherine A Roach
- National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV, 26505, USA
| | - Alycia K Knepp
- National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV, 26505, USA
| | - Elizabeth D Arnold
- National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV, 26505, USA
| | - Aleksandr B Stefaniak
- National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV, 26505, USA.
| | - M Abbas Virji
- National Institute for Occupational Safety and Health, 1095 Willowdale Road, Morgantown, WV, 26505, USA
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11
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Alijagic A, Engwall M, Särndahl E, Karlsson H, Hedbrant A, Andersson L, Karlsson P, Dalemo M, Scherbak N, Färnlund K, Larsson M, Persson A. Particle Safety Assessment in Additive Manufacturing: From Exposure Risks to Advanced Toxicology Testing. FRONTIERS IN TOXICOLOGY 2022; 4:836447. [PMID: 35548681 PMCID: PMC9081788 DOI: 10.3389/ftox.2022.836447] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 04/06/2022] [Indexed: 11/13/2022] Open
Abstract
Additive manufacturing (AM) or industrial three-dimensional (3D) printing drives a new spectrum of design and production possibilities; pushing the boundaries both in the application by production of sophisticated products as well as the development of next-generation materials. AM technologies apply a diversity of feedstocks, including plastic, metallic, and ceramic particle powders with distinct size, shape, and surface chemistry. In addition, powders are often reused, which may change the particles' physicochemical properties and by that alter their toxic potential. The AM production technology commonly relies on a laser or electron beam to selectively melt or sinter particle powders. Large energy input on feedstock powders generates several byproducts, including varying amounts of virgin microparticles, nanoparticles, spatter, and volatile chemicals that are emitted in the working environment; throughout the production and processing phases. The micro and nanoscale size may enable particles to interact with and to cross biological barriers, which could, in turn, give rise to unexpected adverse outcomes, including inflammation, oxidative stress, activation of signaling pathways, genotoxicity, and carcinogenicity. Another important aspect of AM-associated risks is emission/leakage of mono- and oligomers due to polymer breakdown and high temperature transformation of chemicals from polymeric particles, both during production, use, and in vivo, including in target cells. These chemicals are potential inducers of direct toxicity, genotoxicity, and endocrine disruption. Nevertheless, understanding whether AM particle powders and their byproducts may exert adverse effects in humans is largely lacking and urges comprehensive safety assessment across the entire AM lifecycle-spanning from virgin and reused to airborne particles. Therefore, this review will detail: 1) brief overview of the AM feedstock powders, impact of reuse on particle physicochemical properties, main exposure pathways and protective measures in AM industry, 2) role of particle biological identity and key toxicological endpoints in the particle safety assessment, and 3) next-generation toxicology approaches in nanosafety for safety assessment in AM. Altogether, the proposed testing approach will enable a deeper understanding of existing and emerging particle and chemical safety challenges and provide a strategy for the development of cutting-edge methodologies for hazard identification and risk assessment in the AM industry.
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Affiliation(s)
- Andi Alijagic
- Man-Technology-Environment Research Center (MTM), Örebro University, Örebro, Sweden
- Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Magnus Engwall
- Man-Technology-Environment Research Center (MTM), Örebro University, Örebro, Sweden
| | - Eva Särndahl
- Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Helen Karlsson
- Department of Health, Medicine and Caring Sciences, Occupational and Environmental Medicine Center in Linköping, Linköping University, Linköping, Sweden
| | - Alexander Hedbrant
- Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Lena Andersson
- Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- Department of Occupational and Environmental Medicine, Örebro University, Örebro, Sweden
| | - Patrik Karlsson
- Department of Mechanical Engineering, Örebro University, Örebro, Sweden
| | | | - Nikolai Scherbak
- Man-Technology-Environment Research Center (MTM), Örebro University, Örebro, Sweden
| | | | - Maria Larsson
- Man-Technology-Environment Research Center (MTM), Örebro University, Örebro, Sweden
| | - Alexander Persson
- Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
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12
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Zoabi A, Redenski I, Oren D, Kasem A, Zigron A, Daoud S, Moskovich L, Kablan F, Srouji S. 3D Printing and Virtual Surgical Planning in Oral and Maxillofacial Surgery. J Clin Med 2022; 11:jcm11092385. [PMID: 35566511 PMCID: PMC9104292 DOI: 10.3390/jcm11092385] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 04/15/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023] Open
Abstract
Compared to traditional manufacturing methods, additive manufacturing and 3D printing stand out in their ability to rapidly fabricate complex structures and precise geometries. The growing need for products with different designs, purposes and materials led to the development of 3D printing, serving as a driving force for the 4th industrial revolution and digitization of manufacturing. 3D printing has had a global impact on healthcare, with patient-customized implants now replacing generic implantable medical devices. This revolution has had a particularly significant impact on oral and maxillofacial surgery, where surgeons rely on precision medicine in everyday practice. Trauma, orthognathic surgery and total joint replacement therapy represent several examples of treatments improved by 3D technologies. The widespread and rapid implementation of 3D technologies in clinical settings has led to the development of point-of-care treatment facilities with in-house infrastructure, enabling surgical teams to participate in the 3D design and manufacturing of devices. 3D technologies have had a tremendous impact on clinical outcomes and on the way clinicians approach treatment planning. The current review offers our perspective on the implementation of 3D-based technologies in the field of oral and maxillofacial surgery, while indicating major clinical applications. Moreover, the current report outlines the 3D printing point-of-care concept in the field of oral and maxillofacial surgery.
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Affiliation(s)
- Adeeb Zoabi
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Idan Redenski
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Daniel Oren
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Adi Kasem
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Asaf Zigron
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Shadi Daoud
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Liad Moskovich
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Fares Kablan
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Samer Srouji
- Department of Oral and Maxillofacial Surgery, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya 2210001, Israel; (A.Z.); (I.R.); (D.O.); (A.K.); (A.Z.); (S.D.); (L.M.); (F.K.)
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
- Correspondence:
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13
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Zhang Q, Davis AY, Black MS. Emissions and Chemical Exposure Potentials from Stereolithography Vat Polymerization 3D Printing and Post-processing Units. ACS CHEMICAL HEALTH & SAFETY 2022. [DOI: 10.1021/acs.chas.2c00002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Qian Zhang
- Chemical Insights Research Institute, Underwriters Laboratories Inc., Marietta, Georgia 30067, United States
| | - Aika Y. Davis
- Chemical Insights Research Institute, Underwriters Laboratories Inc., Marietta, Georgia 30067, United States
| | - Marilyn S. Black
- Chemical Insights Research Institute, Underwriters Laboratories Inc., Marietta, Georgia 30067, United States
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14
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Väisänen A, Alonen L, Ylönen S, Hyttinen M. Organic compound and particle emissions of additive manufacturing with photopolymer resins and chemical outgassing of manufactured resin products. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2022; 85:198-216. [PMID: 34763622 DOI: 10.1080/15287394.2021.1998814] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Photopolymer resins are applied at an increasing rate in additive manufacturing (AM) industry as vat photopolymerization (VP) and material jetting (MJ) methods gain more popularity. The aim of this study was to measure volatile organic compound (VOC), carbonyl compound, ultrafine particle (UFP), and particulate matter (PM10) air concentrations emitted in 3D printer operations. Individual chemicals were identified when multiple photopolymer resin feedstocks were used in various VP and MJ printers. The size distributions of UFPs, and indoor air parameters were also monitored. Finally, the VOC outgassing of the cured resin materials was determined over 84 days. The data demonstrated that 3D printer operators were exposed to low concentrations of airborne exposure agents as follows: average concentrations of VOCs were between 41 and 87 µg/m3, UFP number levels ranged between 0.19 and 3.62 × 103 number/cm3; however, no impact was detected on air parameters or PM10 concentrations. A majority of the UFPs existed in the 10-45 nm size range. The identified compounds included hazardous species included sensitizing acrylates and carcinogenic formaldehyde. The outgassed products included similar compounds that were encountered during the AM processes, and post-processing solvents. Products heated to 37°C emitted 1.4‒2.9-fold more VOCs than at room temperature. Total emissions were reduced by 84‒96% after 28 days roughly from 3000-14000 to 100-1000 µg/m2/hr. In conclusion, resin printer operators are exposed to low concentrations of hazardous emissions, which might result in adverse health outcomes during prolonged exposure. Manufactured resin products are suggested to be stored for 4 weeks after their production to reduce potential consumer VOC hazards.
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Affiliation(s)
- Antti Väisänen
- Faculty of Science and Forestry, Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Lauri Alonen
- School of Engineering and Technology, Savonia University of Applied Sciences, Kuopio, Finland
| | - Sampsa Ylönen
- School of Engineering and Technology, Savonia University of Applied Sciences, Kuopio, Finland
| | - Marko Hyttinen
- Faculty of Science and Forestry, Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
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15
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Cammalleri V, Pocino RN, Marotta D, Protano C, Sinibaldi F, Simonazzi S, Petyx M, Iavicoli S, Vitali M. Occupational scenarios and exposure assessment to formaldehyde: A systematic review. INDOOR AIR 2022; 32:e12949. [PMID: 34708443 PMCID: PMC9298394 DOI: 10.1111/ina.12949] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 10/07/2021] [Accepted: 10/13/2021] [Indexed: 05/25/2023]
Abstract
The objectives of the systematic review were to: identify the work sectors at risk for exposure to formaldehyde; investigate the procedures applied to assess occupational exposure; evaluate the reported exposure levels among the different settings. An electronic search of Pubmed, Scopus, Web of Science and ToxNet was carried out for collecting all the articles on the investigated issue published from January 1, 2004 to September 30, 2019. Forty-three papers were included in the review, and evidenced a great number of occupational scenarios at risk for formaldehyde exposure. All the included studies collected data on formaldehyde exposure levels by a similar approach: environmental and personal sampling followed by chromatographic analyses. Results ranged from not detectable values until to some mg m-3 of airborne formaldehyde. The riskiest occupational settings for formaldehyde exposure were the gross anatomy and pathology laboratories, the hairdressing salons and some specific productive settings, such as wooden furniture factories, dairy facilities and fish hatcheries. Notice that formaldehyde, a well-known carcinogen, was recovered in air at levels higher than outdoor in almost all the studied scenarios/activities; thus, when formaldehyde cannot be removed or substituted, targeted strategies for exposure elimination or mitigation must be adopted.
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Affiliation(s)
- Vittoria Cammalleri
- Department of Public Health and Infectious DiseasesUniversity of Rome “La Sapienza”RomeItaly
| | - Roberta Noemi Pocino
- Department of Public Health and Infectious DiseasesUniversity of Rome “La Sapienza”RomeItaly
| | - Daniela Marotta
- Department of Public Health and Infectious DiseasesUniversity of Rome “La Sapienza”RomeItaly
| | - Carmela Protano
- Department of Public Health and Infectious DiseasesUniversity of Rome “La Sapienza”RomeItaly
| | - Federica Sinibaldi
- Department of Anatomical Histological Medical Legal Sciences and Locomotor ApparatusUniversity of Rome “La Sapienza”RomeItaly
| | - Stefano Simonazzi
- Department of Anatomical Histological Medical Legal Sciences and Locomotor ApparatusUniversity of Rome “La Sapienza”RomeItaly
| | - Marta Petyx
- Department of Occupational and Environmental Medicine, Epidemiology and HygieneINAIL ResearchRomeItaly
| | - Sergio Iavicoli
- Department of Occupational and Environmental Medicine, Epidemiology and HygieneINAIL ResearchRomeItaly
| | - Matteo Vitali
- Department of Public Health and Infectious DiseasesUniversity of Rome “La Sapienza”RomeItaly
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16
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Krechmer JE, Phillips B, Chaloux N, Shomberg R, Daube C, Manchanda G, Murray S, McCarthy A, Fonseca R, Thakkar J, Loose B, Herndon SC, Jayne JT, Worsnop DR, Canagaratna MR. Chemical Emissions from Cured and Uncured 3D-Printed Ventilator Patient Circuit Medical Parts. ACS OMEGA 2021; 6:30726-30733. [PMID: 34805700 PMCID: PMC8600644 DOI: 10.1021/acsomega.1c04695] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 10/22/2021] [Indexed: 05/27/2023]
Abstract
Medical shortages during the COVID-19 pandemic saw numerous efforts to 3D print personal protective equipment and treatment supplies. There is, however, little research on the potential biocompatibility of 3D-printed parts using typical polymeric resins as pertaining to volatile organic compounds (VOCs), which have specific relevance for respiratory circuit equipment. Here, we measured VOCs emitted from freshly printed stereolithography (SLA) replacement medical parts using proton transfer reaction mass spectrometry and infrared differential absorption spectroscopy, and particulates using a scanning mobility particle sizer. We observed emission factors for individual VOCs ranging from ∼0.001 to ∼10 ng cm-3 min-1. Emissions were heavily dependent on postprint curing and mildly dependent on the type of SLA resin. Curing reduced the emission of all observed chemicals, and no compounds exceeded the recommended dose of 360 μg/d. VOC emissions steadily decreased for all parts over time, with an average e-folding time scale (time to decrease to 1/e of the starting value) of 2.6 ± 0.9 h.
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Affiliation(s)
- Jordan E. Krechmer
- Aerodyne
Research, Inc., 45 Manning
Road, Billerica, Massachusetts 01821, United States
| | - Brennan Phillips
- Department
of Ocean Engineering, The University of
Rhode Island, 215 South
Ferry Road, Narragansett, Rhode Island 02882, United States
| | - Nicholas Chaloux
- Department
of Ocean Engineering, The University of
Rhode Island, 215 South
Ferry Road, Narragansett, Rhode Island 02882, United States
| | - Russell Shomberg
- Department
of Ocean Engineering, The University of
Rhode Island, 215 South
Ferry Road, Narragansett, Rhode Island 02882, United States
| | - Conner Daube
- Aerodyne
Research, Inc., 45 Manning
Road, Billerica, Massachusetts 01821, United States
| | - Gaurav Manchanda
- Formlabs,
Inc., 35 Medford Street, Somerville, Massachusetts 02143, United States
| | - Sam Murray
- Formlabs,
Inc., 35 Medford Street, Somerville, Massachusetts 02143, United States
| | - Alex McCarthy
- Formlabs,
Inc., 35 Medford Street, Somerville, Massachusetts 02143, United States
| | - Rodrigo Fonseca
- Computer
Science Department, Brown University, Providence, Rhode Island 02903, United States
| | - Jinen Thakkar
- Department
of Medicine, Brown University and Alpert
Medical School, Providence, Rhode Island 02903, United States
| | - Brice Loose
- Department
of Ocean Engineering, The University of
Rhode Island, 215 South
Ferry Road, Narragansett, Rhode Island 02882, United States
| | - Scott C. Herndon
- Aerodyne
Research, Inc., 45 Manning
Road, Billerica, Massachusetts 01821, United States
| | - John T. Jayne
- Aerodyne
Research, Inc., 45 Manning
Road, Billerica, Massachusetts 01821, United States
| | - Douglas R. Worsnop
- Aerodyne
Research, Inc., 45 Manning
Road, Billerica, Massachusetts 01821, United States
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17
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Dobrzyńska E, Kondej D, Kowalska J, Szewczyńska M. State of the art in additive manufacturing and its possible chemical and particle hazards-review. INDOOR AIR 2021; 31:1733-1758. [PMID: 34081372 PMCID: PMC8596642 DOI: 10.1111/ina.12853] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/29/2021] [Accepted: 04/21/2021] [Indexed: 05/27/2023]
Abstract
Additive manufacturing, enabling rapid prototyping and so-called on-demand production, has become a common method of creating parts or whole devices. On a 3D printer, real objects are produced layer by layer, thus creating extraordinary possibilities as to the number of applications for this type of devices. The opportunities offered by this technique seem to be pushing new boundaries when it comes to both the use of 3D printing in practice and new materials from which the 3D objects can be printed. However, the question arises whether, at the same time, this solution is safe enough to be used without limitations, wherever and by everyone. According to the scientific reports, three-dimensional printing can pose a threat to the user, not only in terms of physical or mechanical hazards, but also through the potential emissions of chemical substances and fine particles. Thus, the presented publication collects information on the additive manufacturing, different techniques, and ways of printing with application of diverse raw materials. It presents an overview of the last 5 years' publications focusing on 3D printing, especially regarding the potential chemical and particle emission resulting from the use of such printers in both the working environment and private spaces.
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Affiliation(s)
- Elżbieta Dobrzyńska
- Central Institute for Labour Protection—National Research InstituteWarsawPoland
| | - Dorota Kondej
- Central Institute for Labour Protection—National Research InstituteWarsawPoland
| | - Joanna Kowalska
- Central Institute for Labour Protection—National Research InstituteWarsawPoland
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18
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Väisänen AJK, Alonen L, Ylönen S, Lyijynen I, Hyttinen M. The impact of thermal reprocessing of 3D printable polymers on their mechanical performance and airborne pollutant profiles. JOURNAL OF POLYMER RESEARCH 2021. [DOI: 10.1007/s10965-021-02723-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AbstractThe alterations in volatile organic compound (VOC) and ultrafine particulate (UFP) matter emission profiles following thermal reprocessing of multiple materials were examined. Additionally, mechanical performance of the materials was studied. The VOCs were identified by collecting air samples with Tenax® TA tubes and analyzing them with a GC–MS system. UFP concentrations were monitored with a portable ultrafine particle counter. Total VOC emissions of all materials were reduced by 28–68% after 5 thermal cycles (TCs). However, slight accumulation of 1,4-dioxane was observed with poly(lactic acid) materials. UFP emissions were reduced by 45–88% for 3D printing grade materials over 5 TCs but increased by 62% in the case of a waste plastic material over 3 TCs. The mechanical performance of the materials was investigated by measuring their tensile strengths (TSs) and elastic moduli (EM) with an axial-torsion testing system. The reprocessed materials expressed fluctuations in their 3D printing qualities and mechanical performances. The mechanical performances were observed to reduce only slightly after 5 TCs, and the trend was observable only after the data was mass-normalized. The TSs of the samples were reduced by 10–24%, while the EM were reduced by 1–9% after 5 TCs. The TS and EM of one material were increased by 14 and 33%, respectively. In conclusion, recycled polymers are plausible 3D printing feedstock alternatives as they possess acceptable mechanical performance and low emittance according to this study. Furthermore, non-3D printing grade polymers may be applied in a 3D printer with caution.
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19
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Murashov V, Geraci CL, Schulte PA, Howard J. Nano- and microplastics in the workplace. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2021; 18:489-494. [PMID: 34478348 PMCID: PMC10020928 DOI: 10.1080/15459624.2021.1976413] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Affiliation(s)
- Vladimir Murashov
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Washington, DC
| | - Charles L Geraci
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Washington, DC
| | - Paul A Schulte
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Washington, DC
| | - John Howard
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Washington, DC
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20
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Runström Eden G, Tinnerberg H, Rosell L, Möller R, Almstrand AC, Bredberg A. Exploring Methods for Surveillance of Occupational Exposure from Additive Manufacturing in Four Different Industrial Facilities. Ann Work Expo Health 2021; 66:163-177. [PMID: 34486024 PMCID: PMC8855698 DOI: 10.1093/annweh/wxab070] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 07/08/2021] [Accepted: 08/16/2021] [Indexed: 01/11/2023] Open
Abstract
3D printing, a type of additive manufacturing (AM), is a rapidly expanding field. Some adverse health effects have been associated with exposure to printing emissions, which makes occupational exposure studies important. There is a lack of exposure studies, particularly from printing methods other than material extrusion (ME). The presented study aimed to evaluate measurement methods for exposure assessment in AM environments and to measure exposure and emissions from four different printing methods [powder bed fusion (PBF), material extrusion (ME), material jetting (MJ), and vat photopolymerization] in industry. Structured exposure diaries and volatile organic compound (VOC) sensors were used over a 5-day working week. Personal and stationary VOC samples and real-time particle measurements were taken for 1 day per facility. Personal inhalable and respirable dust samples were taken during PBF and MJ AM. The use of structured exposure diaries in combination with measurement data revealed that comparatively little time is spent on actual printing and the main exposure comes from post-processing tasks. VOC and particle instruments that log for a longer period are a useful tool as they facilitate the identification of work tasks with high emissions, highlight the importance of ventilation and give a more gathered view of variations in exposure. No alarming levels of VOCs or dust were detected during print nor post-processing in these facilities as adequate preventive measures were installed. As there are a few studies reporting negative health effects, it is still important to keep the exposure as low as reasonable.
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Affiliation(s)
- Gunilla Runström Eden
- University of Gothenburg, Institute of Medicine, Sahlgrenska Academy, School of Public Health and Community Medicine, Gothenburg, Sweden
| | - Håkan Tinnerberg
- University of Gothenburg, Institute of Medicine, Sahlgrenska Academy, School of Public Health and Community Medicine, Gothenburg, Sweden
| | - Lars Rosell
- RISE, Research Institutes of Sweden, Gothenburg, Sweden
| | - Rickie Möller
- University of Gothenburg, Institute of Medicine, Sahlgrenska Academy, School of Public Health and Community Medicine, Gothenburg, Sweden
| | - Ann-Charlotte Almstrand
- University of Gothenburg, Institute of Medicine, Sahlgrenska Academy, School of Public Health and Community Medicine, Gothenburg, Sweden
| | - Anna Bredberg
- RISE, Research Institutes of Sweden, Gothenburg, Sweden
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21
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Stefaniak AB, Bowers LN, Cottrell G, Erdem E, Knepp AK, Martin S, Pretty J, Duling MG, Arnold ED, Wilson Z, Krider B, LeBouf RF, Virji MA, Sirinterlikci A. Use of 3-Dimensional Printers in Educational Settings: The Need for Awareness of the Effects of Printer Temperature and Filament Type on Contaminant Releases. ACS CHEMICAL HEALTH & SAFETY 2021; 28:444-456. [PMID: 35979087 PMCID: PMC9377640 DOI: 10.1021/acs.chas.1c00041] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Material extrusion-type fused filament fabrication (FFF) 3-D printing is a valuable tool for education. During FFF 3-D printing, thermal degradation of the polymer releases small particles and chemicals, many of which are hazardous to human health. In this study, particle and chemical emissions from 10 different filaments made from virgin (never printed) and recycled polymers were used to print the same object at the polymer manufacturer's recommended nozzle temperature ("normal") and at a temperature higher than recommended ("hot") to simulate the real-world scenarios of a person intentionally or unknowingly printing on a machine with a changed setting. Emissions were evaluated in a college teaching laboratory using standard sampling and analytical methods. From mobility sizer measurements, particle number-based emission rates were 81 times higher; the proportion of ultrafine particles (diameter <100 nm) were 4% higher, and median particle sizes were a factor of 2 smaller for hot-temperature prints compared with normal-temperature prints (all p-values <0.05). There was no difference in emission characteristics between recycled and virgin acrylonitrile butadiene styrene and polylactic acid polymer filaments. Reducing contaminant release from FFF 3-D printers in educational settings can be achieved using the hierarchy of controls: (1) elimination/substitution (e.g., training students on principles of prevention-through-design, limiting the use of higher emitting polymer when possible); (2) engineering controls (e.g., using local exhaust ventilation to directly remove contaminants at the printer or isolating the printer from students); (3) administrative controls such as password protecting printer settings and establishing and enforcing adherence to a standard operating procedure based on a proper risk assessment for the setup and use (e.g., limiting the use of temperatures higher than those specified for the filaments used); and (4) maintenance of printers.
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Affiliation(s)
- Aleksandr B Stefaniak
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Lauren N Bowers
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Gabe Cottrell
- School of Engineering, Mathematics, and Science, Robert Morris University, Moon Township, Pennsylvania 15108, United States
| | - Ergin Erdem
- School of Engineering, Mathematics, and Science, Robert Morris University, Moon Township, Pennsylvania 15108, United States
| | - Alycia K Knepp
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Stephen Martin
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Jack Pretty
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Cincinnati, Ohio 45213, United States
| | - Matthew G Duling
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Elizabeth D Arnold
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Zachary Wilson
- School of Engineering, Mathematics, and Science, Robert Morris University, Moon Township, Pennsylvania 15108, United States
| | - Benjamin Krider
- School of Engineering, Mathematics, and Science, Robert Morris University, Moon Township, Pennsylvania 15108, United States
| | - Ryan F LeBouf
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - M Abbas Virji
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Arif Sirinterlikci
- School of Engineering, Mathematics, and Science, Robert Morris University, Moon Township, Pennsylvania 15108, United States
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Leso V, Ercolano ML, Mazzotta I, Romano M, Cannavacciuolo F, Iavicoli I. Three-Dimensional (3D) Printing: Implications for Risk Assessment and Management in Occupational Settings. Ann Work Expo Health 2021; 65:617-634. [PMID: 33616163 DOI: 10.1093/annweh/wxaa146] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 11/29/2020] [Accepted: 12/24/2020] [Indexed: 01/21/2023] Open
Abstract
The widespread application of additive manufacturing (AM) technologies, commonly known as three-dimensional (3D) printing, in industrial and home-business sectors, and the expected increase in the number of workers and consumers that use these devices, have raised concerns regarding the possible health implications of 3D printing emissions. To inform the risk assessment and management processes, this review evaluates available data concerning exposure assessment in AM workplaces and possible effects of 3D printing emissions on humans identified through in vivo and in vitro models in order to inform risk assessment and management processes. Peer-reviewed literature was identified in Pubmed, Scopus, and ISI Web of Science databases. The literature demonstrated that a significant fraction of the particles released during 3D printing could be in the ultrafine size range. Depending upon the additive material composition, increased levels of metals and volatile organic compounds could be detected during AM operations, compared with background levels. AM phases, specific job tasks performed, and preventive measures adopted may all affect exposure levels. Regarding possible health effects, printer emissions were preliminary reported to affect the respiratory system of involved workers. The limited number of workplace studies, together with the great variety of AM techniques and additive materials employed, limit generalizability of exposure features. Therefore, greater scientific efforts should be focused at understanding sources, magnitudes, and possible health effects of exposures to develop suitable processes for occupational risk assessment and management of AM technologies.
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Affiliation(s)
- Veruscka Leso
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Naples, Italy
| | - Maria Luigia Ercolano
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Naples, Italy
| | - Ines Mazzotta
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Naples, Italy
| | - Marco Romano
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Naples, Italy
| | - Francesca Cannavacciuolo
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Naples, Italy
| | - Ivo Iavicoli
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Naples, Italy
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Stefaniak A, Du Preez S, Du Plessis JL. Additive Manufacturing for Occupational Hygiene: A Comprehensive Review of Processes, Emissions, & Exposures. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2021; 24:1-50. [PMID: 34139957 PMCID: PMC8678392 DOI: 10.1080/10937404.2021.1936319] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This comprehensive review introduces occupational (industrial) hygienists and toxicologists to the seven basic additive manufacturing (AM) process categories. Forty-six articles were identified that reported real-world measurements for all AM processes, except sheet lamination. Particles released from powder bed fusion (PBF), material jetting (MJ), material extrusion (ME), and directed energy deposition (DED) processes exhibited nanoscale to submicron scale; real-time particle number (mobility sizers, condensation nuclei counters, miniDiSC, electrical diffusion batteries) and surface area monitors (diffusion chargers) were generally sufficient for these processes. Binder jetting (BJ) machines released particles up to 8.5 µm; optical particle sizers (number) and laser scattering photometers (mass) were sufficient for this process. PBF and DED processes (powdered metallic feedstocks) released particles that contained respiratory irritants (chromium, molybdenum), central nervous system toxicants (manganese), and carcinogens (nickel). All process categories, except those that use metallic feedstocks, released organic gases, including (but not limited to), respiratory irritants (toluene, xylenes), asthmagens (methyl methacrylate, styrene), and carcinogens (benzene, formaldehyde, acetaldehyde). Real-time photoionization detectors for total volatile organics provided useful information for processes that utilize polymer feedstock materials. More research is needed to understand 1) facility-, machine-, and feedstock-related factors that influence emissions and exposures, 2) dermal exposure and biological burden, and 3) task-based exposures. Harmonized emissions monitoring and exposure assessment approaches are needed to facilitate inter-comparison of study results. Improved understanding of AM process emissions and exposures is needed for hygienists to ensure appropriate health and safety conditions for workers and for toxicologists to design experimental protocols that accurately mimic real-world exposure conditions.ABBREVIATIONS ABS : acrylonitrile butadiene styrene; ACGIH® TLV® : American Conference of Governmental Industrial Hygienists Threshold Limit Value; ACH : air change per hour; AM : additive manufacturing; ASA : acrylonitrile styrene acrylate; AVP : acetone vapor polishing; BJ : binder jetting; CAM-LEM : computer-aided manufacturing of laminated engineering materials; CNF : carbon nanofiber; CNT : carbon nanotube; CP : co-polyester; CNC : condensation nuclei counter; CVP : chloroform vapor polishing; DED : directed energy deposition; DLP : digital light processing; EBM : electron beam melting; EELS : electron energy loss spectrometry; EDB : electrical diffusion batteries; EDX : energy dispersive x-ray analyzer; ER : emission rate; FDM™ : fused deposition modeling; FFF : fused filament fabrication; IAQ : indoor air quality; LSP : laser scattering photometer; LCD : liquid crystal display; LDSA : lung deposited particle surface area; LOD : limit of detection; LOM : laminated object manufacturing; LOQ : limit of quantitation; MCE : mixed cellulose ester filter; ME : material extrusion; MJ : material jetting; OEL : occupational exposure limit; OPS : optical particle sizer; PBF : powder bed fusion; PBZ : personal breathing zone; PC : polycarbonate; PEEK : poly ether ether ketone; PET : polyethylene terephthalate; PETG : Polyethylene terephthalate glycol; PID : photoionization detector; PLA : polylactic acid; PM1 : particulate matter with aerodynamic diameter less than 1 µm; PM2.5 : particulate matter with aerodynamic diameter less than 2.5 µm; PM10 : particulate matter with aerodynamic diameter less than 10 µm; PSL : plastic sheet lamination; PVA : polyvinyl alcohol; REL : recommended exposure limit; SDL : selective deposition lamination; SDS : safety data sheet; SEM : scanning electron microscopy; SL : sheet lamination; SLA : stereolithography; SLM : selective laser melting; SMPS : scanning mobility particle sizer; SVOC : semi-volatile organic compound; TEM : transmission electron microscopy; TGA : thermal gravimetric analysis; TPU : thermo polyurethane; UAM : ultrasonic additive manufacturing; UC : ultrasonic consolidation; TVOC : total volatile organic compounds; TWA : time-weighted average; VOC : volatile organic compound; VP : vat photopolymerization.
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Affiliation(s)
- A.B. Stefaniak
- Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - S Du Preez
- North-West University, Occupational Hygiene and Health Research Initiative, Potchefstroom, South Africa
| | - JL Du Plessis
- North-West University, Occupational Hygiene and Health Research Initiative, Potchefstroom, South Africa
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Stefaniak AB, Bowers LN, Martin SB, Hammond DR, Ham JE, Wells JR, Fortner AR, Knepp AK, du Preez S, Pretty JR, Roberts JL, du Plessis JL, Schmidt A, Duling MG, Bader A, Virji MA. Large-Format Additive Manufacturing and Machining Using High-Melt-Temperature Polymers. Part II: Characterization of Particles and Gases. ACS CHEMICAL HEALTH & SAFETY 2021; 28:268-278. [DOI: 10.1021/acs.chas.0c00129] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Aleksandr B. Stefaniak
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Lauren N. Bowers
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Stephen B. Martin
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Duane R. Hammond
- National Institute for Occupational Safety and Health, Cincinnati, Ohio 45213, United States
| | - Jason E. Ham
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - J. R. Wells
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Alyson R. Fortner
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Alycia K. Knepp
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Sonette du Preez
- North-West University, Occupational Hygiene and Health Research Initiative, Private Bag X6001, Potchefstroom 2520, South Africa
| | - Jack R. Pretty
- National Institute for Occupational Safety and Health, Cincinnati, Ohio 45213, United States
| | - Jennifer L. Roberts
- National Institute for Occupational Safety and Health, Cincinnati, Ohio 45213, United States
| | - Johan L. du Plessis
- North-West University, Occupational Hygiene and Health Research Initiative, Private Bag X6001, Potchefstroom 2520, South Africa
| | - Austin Schmidt
- Additive Engineering Solutions, Akron, Ohio 44305, United States
| | - Matthew G. Duling
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Andrew Bader
- Additive Engineering Solutions, Akron, Ohio 44305, United States
| | - M. Abbas Virji
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
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25
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Stefaniak AB, Bowers LN, Martin SB, Hammond DR, Ham JE, Wells JR, Fortner AR, Knepp AK, du Preez S, Pretty JR, Roberts JL, du Plessis JL, Schmidt A, Duling MG, Bader A, Virji MA. Large-Format Additive Manufacturing and Machining Using High-Melt-Temperature Polymers. Part I: Real-Time Particulate and Gas-Phase Emissions. ACS CHEMICAL HEALTH & SAFETY 2021; 28:190-200. [PMID: 35979329 PMCID: PMC9380575 DOI: 10.1021/acs.chas.0c00128] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The literature on emissions during material extrusion additive manufacturing with 3-D printers is expanding; however, there is a paucity of data for large-format additive manufacturing (LFAM) machines that can extrude high-melt-temperature polymers. Emissions from two LFAM machines were monitored during extrusion of six polymers: acrylonitrile butadiene styrene (ABS), polycarbonate (PC), high-melt-temperature polysulfone (PSU), poly(ether sulfone) (PESU), polyphenylene sulfide (PPS), and Ultem (poly(ether imide)). Particle number, total volatile organic compound (TVOC), carbon monoxide (CO), and carbon dioxide (CO2) concentrations were monitored in real-time. Particle emission rate values (no./min) were as follows: ABS (1.7 × 1011 to 7.7 × 1013), PC (5.2 × 1011 to 3.6 × 1013), Ultem (5.7 × 1012 to 3.1 × 1013), PPS (4.6 × 1011 to 6.2 × 1012), PSU (1.5 × 1012 to 3.4 × 1013), and PESU (2.0 to 5.0 × 1013). For print jobs where the mass of extruded polymer was known, particle yield values (g-1 extruded) were as follows: ABS (4.5 × 108 to 2.9 × 1011), PC (1.0 × 109 to 1.7 × 1011), PSU (5.1 × 109 to 1.2 × 1011), and PESU (0.8 × 1011 to 1.7 × 1011). TVOC emission yields ranged from 0.005 mg/g extruded (PESU) to 0.7 mg/g extruded (ABS). The use of wall-mounted exhaust ventilation fans was insufficient to completely remove airborne particulate and TVOC from the print room. Real-time CO monitoring was not a useful marker of particulate and TVOC emission profiles for Ultem, PPS, or PSU. Average CO2 and particle concentrations were moderately correlated (r s = 0.76) for PC polymer. Extrusion of ABS, PC, and four high-melt-temperature polymers by LFAM machines released particulate and TVOC at levels that could warrant consideration of engineering controls. LFAM particle emission yields for some polymers were similar to those of common desktop-scale 3-D printers.
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Affiliation(s)
- Aleksandr B Stefaniak
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Lauren N Bowers
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Stephen B Martin
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Duane R Hammond
- National Institute for Occupational Safety and Health, Cincinnati, Ohio 45213, United States
| | - Jason E Ham
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - J R Wells
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Alyson R Fortner
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Alycia K Knepp
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Sonette du Preez
- North-West University, Occupational Hygiene and Health Research Initiative, Potchefstroom 2520, South Africa
| | - Jack R Pretty
- National Institute for Occupational Safety and Health, Cincinnati, Ohio 45213, United States
| | - Jennifer L Roberts
- National Institute for Occupational Safety and Health, Cincinnati, Ohio 45213, United States
| | - Johan L du Plessis
- North-West University, Occupational Hygiene and Health Research Initiative, Potchefstroom 2520, South Africa
| | - Austin Schmidt
- Additive Engineering Solutions, Akron, Ohio 44305, United States
| | - Matthew G Duling
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
| | - Andrew Bader
- Additive Engineering Solutions, Akron, Ohio 44305, United States
| | - M Abbas Virji
- National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, United States
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26
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Chen R, Yin H, Cole IS, Shen S, Zhou X, Wang Y, Tang S. Exposure, assessment and health hazards of particulate matter in metal additive manufacturing: A review. CHEMOSPHERE 2020; 259:127452. [PMID: 32629313 DOI: 10.1016/j.chemosphere.2020.127452] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/11/2020] [Accepted: 06/15/2020] [Indexed: 05/15/2023]
Abstract
Metal additive manufacturing (AM), also known as metal three-dimensional (3D) printing, is a new technology offering design freedom to create complex structures that has found increasing applications in industrial processes. However, due to the fine metal powders and high temperatures involved, the printing process is likely to generate particulate matter (PM) that has a detrimental impact on the environment and human health. Therefore, comprehensive assessement of the exposure and health hazards of PM pollution related to this technique is urgently required. This review provides general knowledge of metal AM and its possible particle release. The health issues of metal PM are described considering the exposure routes, adverse human health outcomes and influencing factors. Methods of evaluating PM exposure and risk assessment techniques are also summarized. Lastly, future research needs are suggested. The information and knowledge presented in this review will contribute to the understanding, assessment, and control of possible risks in metal AM and benefit the wider metal 3D printing community, which includes machine operators, consumers, R&D scientists, and policymakers.
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Affiliation(s)
- Rui Chen
- Beijing Key Laboratory of Occupational Safety and Health, Beijing Municipal Institute of Labour Protection, Beijing Academy of Science and Technology, Beijing, 100054, China
| | - Hong Yin
- School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Melbourne, VIC 3000, Australia.
| | - Ivan S Cole
- School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Melbourne, VIC 3000, Australia
| | - Shirley Shen
- CSIRO Manufacturing, Bayview Ave, Clayton, Vic 3168, Australia
| | - Xingfan Zhou
- Beijing Key Laboratory of Occupational Safety and Health, Beijing Municipal Institute of Labour Protection, Beijing Academy of Science and Technology, Beijing, 100054, China
| | - Yuqian Wang
- Beijing Key Laboratory of Occupational Safety and Health, Beijing Municipal Institute of Labour Protection, Beijing Academy of Science and Technology, Beijing, 100054, China
| | - Shichuan Tang
- Beijing Key Laboratory of Occupational Safety and Health, Beijing Municipal Institute of Labour Protection, Beijing Academy of Science and Technology, Beijing, 100054, China.
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27
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Farcas MT, McKinney W, Qi C, Mandler KW, Battelli L, Friend SA, Stefaniak AB, Jackson M, Orandle M, Winn A, Kashon M, LeBouf RF, Russ KA, Hammond DR, Burns D, Ranpara A, Thomas TA, Matheson J, Qian Y. Pulmonary and systemic toxicity in rats following inhalation exposure of 3-D printer emissions from acrylonitrile butadiene styrene (ABS) filament. Inhal Toxicol 2020; 32:403-418. [PMID: 33076715 DOI: 10.1080/08958378.2020.1834034] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Fused filament fabrication 3-D printing with acrylonitrile butadiene styrene (ABS) filament emits ultrafine particulates (UFPs) and volatile organic compounds (VOCs). However, the toxicological implications of the emissions generated during 3-D printing have not been fully elucidated. AIM AND METHODS The goal of this study was to investigate the in vivo toxicity of ABS-emissions from a commercial desktop 3-D printer. Male Sprague Dawley rats were exposed to a single concentration of ABS-emissions or air for 4 hours/day, 4 days/week for five exposure durations (1, 4, 8, 15, and 30 days). At 24 hours after the last exposure, rats were assessed for pulmonary injury, inflammation, and oxidative stress as well as systemic toxicity. RESULTS AND DISCUSSION 3-D printing generated particulate with average particle mass concentration of 240 ± 90 µg/m³, with an average geometric mean particle mobility diameter of 85 nm (geometric standard deviation = 1.6). The number of macrophages increased significantly at day 15. In bronchoalveolar lavage, IFN-γ and IL-10 were significantly higher at days 1 and 4, with IL-10 levels reaching a peak at day 15 in ABS-exposed rats. Neither pulmonary oxidative stress responses nor histopathological changes of the lungs and nasal passages were found among the treatments. There was an increase in platelets and monocytes in the circulation at day 15. Several serum biomarkers of hepatic and kidney functions were significantly higher at day 1. CONCLUSIONS At the current experimental conditions applied, it was concluded that the emissions from ABS filament caused minimal transient pulmonary and systemic toxicity.
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Affiliation(s)
- Mariana T Farcas
- National Institute for Occupational Safety and Health, Morgantown, WV, USA.,Pharmaceutical and Pharmacological Sciences, School of Pharmacy, West Virginia University, Morgantown, WV, USA
| | - Walter McKinney
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Chaolong Qi
- National Institute for Occupational Safety and Health, Cincinnati, OH, USA
| | - Kyle W Mandler
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Lori Battelli
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Sherri A Friend
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | | | - Mark Jackson
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Marlene Orandle
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Ava Winn
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Michael Kashon
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Ryan F LeBouf
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Kristen A Russ
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Duane R Hammond
- National Institute for Occupational Safety and Health, Cincinnati, OH, USA
| | - Dru Burns
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Anand Ranpara
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Treye A Thomas
- Office of Hazard Identification and Reduction, U.S. Consumer Product Safety Commission, Rockville, MD, USA
| | - Joanna Matheson
- Office of Hazard Identification and Reduction, U.S. Consumer Product Safety Commission, Rockville, MD, USA
| | - Yong Qian
- National Institute for Occupational Safety and Health, Morgantown, WV, USA
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28
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Zisook RE, Simmons BD, Vater M, Perez A, Donovan EP, Paustenbach DJ, Cyrs WD. Emissions associated with operations of four different additive manufacturing or 3D printing technologies. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2020; 17:464-479. [PMID: 32809925 DOI: 10.1080/15459624.2020.1798012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
In this pilot-scale study, a wide range of potential emissions were evaluated for four types of additive manufacturing (AM) machines. These included material extrusion (using acrylonitrile-butadiene-styrene [ABS]); material jetting (using liquid photopolymer); powder bed fusion (using nylon); and vat photopolymerization (using liquid photopolymer) in an industrial laboratory setting. During isolated operation of AM machines, adjacent area samples were collected for compounds of potential concern (COPCs), including total and individual volatile organic compounds (VOCs), nano- and micron-sized particulate matter, and inorganic gases. A total of 61 compounds were also sampled using a canister followed by gas chromatography and mass spectrometry analysis. Most COPCs were not detected or were measured at concentrations far below relevant occupational exposure limits (OELs) during AM machine operations. Submicron particles, predominantly nanoparticles, were produced during material extrusion printing using ABS at approximately 12,000 particles per cubic centimeter (p cm-3) above background. After subtracting the mean background concentration, the mean concentration for material extrusion printing operations correlated with a calculated emission rate of 2.8 × 1010 p min-1 under the conditions tested. During processing of parts produced using material jetting or powder bed fusion, emissions were generally negligible, although concentrations above background of respirable and total dust were measured during processing of powder bed fusion parts. Results of this pilot-scale study indicate that airborne emissions associated with AM operations are variable, depending on printing and parts handling processes, raw materials, and ventilation characteristics. Although personal samples were not collected in this pilot-scale study, the results can be used to inform future exposure assessments. Based on the results of this evaluation, measurement of submicron particles emitted during material extrusion printing operations and dust associated with handling parts manufactured using powder bed fusion processes should be included in exposure assessments.
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Affiliation(s)
| | | | - Mark Vater
- Cardno ChemRisk, Pittsburgh, Pennsylvania, USA
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Material characterization of polyamide 12 and related agents used in the multi-jet fusion process: complementary application of high-resolution mass spectrometry and other advanced instrumental techniques. MONATSHEFTE FUR CHEMIE 2020. [DOI: 10.1007/s00706-020-02646-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
The powder bed-based 3D printing process called multi-jet fusion from HP is used in various industries for different applications. A polymer powder, the so-called fusing and detailing agents, and an IR source are needed. These novel materials offer some challenges for analytical characterization. High-resolution mass spectrometry in combination with a data base search was used as a tool for comprehensive characterization of the agents, the methanol extract of new polyamide 12 powder, and the methanol extract of a grinded 3D printed part. In addition, thermogravimetric studies were carried out. Besides biocides and substances containing ethoxy units, 2-pyrrolidone and triethylene glycol were identified as organic solvents in the agents. The detailing agent contained 3.7% of 2-pyrrolidone and 11.1% of triethylene glycol. The fusing agent contained 18.7% of 2-pyrrolidone and 8.4% of triethylene glycol. Based on the agents’ different functionalities, the water content of the detailing agent was 18% higher as compared to the fusing agent. In addition, the fusing agent contained a carbon black amount of 5.2%. The methanol extract of new polyamide 12 powder contained remaining monomer and oligomer compounds, as well as the oxidation stabilizer Irganox 1098. In the methanol extract of the grinded 3D printed part the cyclic and linear monomer, oligomers, and oxidation stabilizer were found. Moreover, ingredients of the agents were detected. Residues of 2-pyrrolidone, triethylene glycol, 3-benzisothiazolinone, and substances containing ethoxy units were identified in the methanol extract of the grinded 3D printed part. In contrast, no 2-methyl-4-isothiazolin-3-one was observed.
Graphical abstract
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Chan FL, Hon CY, Tarlo SM, Rajaram N, House R. Emissions and health risks from the use of 3D printers in an occupational setting. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2020; 83:279-287. [PMID: 32316869 DOI: 10.1080/15287394.2020.1751758] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The aim of this study was to determine concentrations of particulates and volatile organic compounds (VOCs) emitted from 3D printers using polylactic acid (PLA) filaments at a university workroom to assess exposure and health risks in an occupational setting. Under typical-case (one printer) and worst-case (three printers operating simultaneously) scenarios, particulate concentration (total and respirable), VOCs and formaldehyde were measured. Air samples were collected in the printing room and adjacent hallway. Size-resolved levels of nano-diameter particles were also collected in the printing room. Total particulate levels were higher in the worst-case scenario (0.7 mg/m3) vs. typical-case scenario (0.3 mg/m3). Respirable particulate and formaldehyde concentrations were similar between the two scenarios. Size-resolved measurements showed that most particles ranged from approximately 27 to 116 nm. Total VOC levels were approximately 6-fold higher during the worst-case scenario vs. typical situation with isopropyl alcohol being the predominant VOC. Airborne concentrations in the hallway were generally lower than inside the printing room. All measurements were below their respective occupational exposure limits. In summary, emissions of particulates and VOCs increased when multiple 3D printers were operating simultaneously. Airborne levels in the adjacent hallway were similar between the two scenarios. Overall, data suggest a low risk of significant and persistent adverse health effects. Nevertheless, the health effects attributed to 3D printing are not fully known and adherence to good hygiene principles is recommended during use of this technology.
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Affiliation(s)
- Felix L Chan
- Division of Occupational Medicine, Department of Medicine, St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Chun-Yip Hon
- School of Occupational and Public Health, Ryerson University, Toronto, ON, Canada
| | - Susan M Tarlo
- Division of Occupational Medicine, Department of Medicine, St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
- Centre for Research Expertise in Occupational Disease, Toronto, ON, Canada
| | - Nikhil Rajaram
- Division of Occupational Medicine, Department of Medicine, St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Ronald House
- Division of Occupational Medicine, Department of Medicine, St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
- Centre for Research Expertise in Occupational Disease, Toronto, ON, Canada
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Yi J, Duling MG, Bowers LN, Knepp AK, LeBouf RF, Nurkiewicz TR, Ranpara A, Luxton T, Martin SB, Burns DA, Peloquin DM, Baumann EJ, Virji MA, Stefaniak AB. Particle and organic vapor emissions from children's 3-D pen and 3-D printer toys. Inhal Toxicol 2019; 31:432-445. [PMID: 31874579 PMCID: PMC6995422 DOI: 10.1080/08958378.2019.1705441] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 12/11/2019] [Indexed: 01/09/2023]
Abstract
Objective: Fused filament fabrication "3-dimensional (3-D)" printing has expanded beyond the workplace to 3-D printers and pens for use by children as toys to create objects.Materials and methods: Emissions from two brands of toy 3-D pens and one brand of toy 3-D printer were characterized in a 0.6 m3 chamber (particle number, size, elemental composition; concentrations of individual and total volatile organic compounds (TVOC)). The effects of print parameters on these emission metrics were evaluated using mixed-effects models. Emissions data were used to model particle lung deposition and TVOC exposure potential.Results: Geometric mean particle yields (106-1010 particles/g printed) and sizes (30-300 nm) and TVOC yields (
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Affiliation(s)
- Jinghai Yi
- Department of Physiology and Pharmacology, and the Center for Inhalation Toxicology, West Virginia University School of Medicine, Morgantown, WV, 26506
| | - Matthew G. Duling
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | - Lauren N. Bowers
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | - Alycia K. Knepp
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | - Ryan F. LeBouf
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | - Timothy R. Nurkiewicz
- Department of Physiology and Pharmacology, and the Center for Inhalation Toxicology, West Virginia University School of Medicine, Morgantown, WV, 26506
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | - Anand Ranpara
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | - Todd Luxton
- U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, Cincinnati, OH, 45224
| | - Stephen B. Martin
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | - Dru A. Burns
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
| | | | | | - M. Abbas Virji
- National Institute for Occupational Safety and Health, Morgantown, WV, 26505
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Petretta M, Desando G, Grigolo B, Roseti L. 3D printing of musculoskeletal tissues: impact on safety and health at work. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2019; 82:891-912. [PMID: 31545145 DOI: 10.1080/15287394.2019.1663458] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Additive manufacturing (commonly referred to as 3D printing) created an attractive approach for regenerative medicine research in musculoskeletal tissue engineering. Given the high number of fabrication technologies available, characterized by different working and physical principles, there are several related risks that need to be managed to protect operators. Recently, an increasing number of studies demonstrated that several types of 3D printers are emitters of ultrafine particles and volatile organic compounds whose harmful effects through inhalation, ingestion and skin uptake are known. Confirmation of danger of these products is not yet final, but this provides a basis to adopt preventive measures in agreement with the precautionary principle. The purpose of this investigation was to provide a useful tool to the researcher for managing the risks related to the use of different kinds of three-dimensional printers (3D printers) in the lab, especiallyconcerning orthopedic applications, and to define appropriate control measures. Particular attention was given to new emerging risks and to developing response strategies for a comprehensive coverage of the health and safety of operators.
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Affiliation(s)
- Mauro Petretta
- RegenHU ltd, Z.I. du Vivier , Villaz-ST-Pierre , Switzerland
- RAMSES Laboratory, Rizzoli RIT-Research, Innovation & Technology Department, Istituto di Ricerca Codivilla Putti, IRCCS Istituto Ortopedico Rizzoli , Bologna , Italy
| | - Giovanna Desando
- RAMSES Laboratory, Rizzoli RIT-Research, Innovation & Technology Department, Istituto di Ricerca Codivilla Putti, IRCCS Istituto Ortopedico Rizzoli , Bologna , Italy
| | - Brunella Grigolo
- RAMSES Laboratory, Rizzoli RIT-Research, Innovation & Technology Department, Istituto di Ricerca Codivilla Putti, IRCCS Istituto Ortopedico Rizzoli , Bologna , Italy
| | - Livia Roseti
- RAMSES Laboratory, Rizzoli RIT-Research, Innovation & Technology Department, Istituto di Ricerca Codivilla Putti, IRCCS Istituto Ortopedico Rizzoli , Bologna , Italy
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