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- Alijagic, Andi, 1992-, et al.
(författare)
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Particle Safety Assessment in Additive Manufacturing : From Exposure Risks to Advanced Toxicology Testing.
- 2022
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Ingår i: Frontiers in Toxicology. - : Frontiers Media S.A.. - 2673-3080. ; 4
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Forskningsöversikt (refereegranskat)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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| 3. |
- Björklund, Anna, et al.
(författare)
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Evaluating a municipal waste management plan using ORWARE
- 1999
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Ingår i: Journal of Cleaner Production. - 0959-6526 .- 1879-1786. ; 7:4, s. 271-280
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Tidskriftsartikel (refereegranskat)abstract
- Environmental consequences of implementing Uppsala's waste management plan have been analysed using ORWARE, a computerized static substance flow model based on life cycle assessment methodology. Normalizing emissions from waste management to total emission loadings in the municipality was tested as a means to improve the evaluation. It was found that anaerobic digestion of biodegradable waste can reduce net environmental impact, while large-scale composting either increases environmental impact or gives less reduction than anaerobic digestion. In either case, metal contamination of digester sludge or compost may limit the feasibility of the systems. Increased materials recycling has the potential of reducing environmental impact, provided that processing of recycled materials causes equal or less environmental impact than extraction and processing of virgin raw materials. Normalization showed that all impact categories were of roughly equal importance. It was shown that easy accessible data published by a Swedish municipality were sufficient to do a relatively comprehensive normalization.
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| 5. |
- Björklund, Anna, et al.
(författare)
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Planning Biodegradable Waste Management in Stockholm
- 1999
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Ingår i: Journal of Industrial Ecology. - 1088-1980 .- 1530-9290. ; 3:4, s. 43-58
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Tidskriftsartikel (refereegranskat)abstract
- The environmental impact of the management of biodegradable waste in Stockholm, based mainly on incineration and landfilling, was compared to systems with significant nutrient recycling; large-scale composting, anaerobic digestion, and separate collection and utilization of urine. The systems' emissions, residual products, energy turnover, and resource consumption were evaluated from a life-cycle perspective, using a computerized model, ORWARE (ORganic WAste REsearch model). Transportation was of relatively low importance to overall environmental impact, even at high rates of nutrient recycling. This is remarkable considering the geographical setting of Stockholm, with high population density and little nearby farmland. Ancillary systems, such as generation of electricity and district heating, were crucial for the overall outcome. Increased recycling of nutrients in solid biodegradable waste in Stockholm can reduce net environmental impact, whereas separation of human urine to be spread as fertilizer cannot yet be introduced without increased acidification. Increased nutrient recycling from solid biodegradable waste inevitably increases spreading of metals on arable land. Urine is by far the least contaminated residual product. Spreading of all other residuals would be limited by their metal content.
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| 9. |
- Dalemo, Magnus, et al.
(författare)
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Effects of including nitrogen emissions from soil in environmental systems analysis of waste management strategies
- 1998
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Ingår i: Resources, Conservation and Recycling. - 0921-3449 .- 1879-0658. ; 24, s. 363-381
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Tidskriftsartikel (refereegranskat)abstract
- The environmental impacts of nitrogen emissions from soil resulting from the use of organic fertilizers, such as manure, are large compared with the corresponding impacts of mineral fertilizers. However, soil emissions are rarely included in systems analysis of waste management strategies. This study examines whether the inclusion of soil emissions can affect the environmental ranking of systems for managing solid biodegradable waste. Waste management scenarios based on incineration, anaerobic digestion and composting, respectively, were compared. The scenarios were analysed using the organic waste research (ORWARE) simulation model. A simplified model for calculating nitrogen availability and emissions was also constructed. Life-cycle analysis methodology was used for choosing system boundaries and evaluating the results. Global warming, acidification and eutrophication were the impact categories considered. The results indicate the vital importance of considering nitrogen emissions from soil when comparing biological waste management systems with other waste management methods, especially with regard to eutrophication effects. Soil emissions are also important when comparing the environmental impacts of anaerobic digestion and composting systems. However, the variation in nitrogen emissions from soil is large and depends on the spreading technique used, climate, drainage and soil texture
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