Browsing by Author "Egizabal, A."
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Item Environmental Particle Emissions due to Automated Drilling of Polypropylene Composites and Nanocomposites Reinforced with Talc, Montmorillonite and Wollastonite(2017-05-11) Starost, K.; Frijns, E.; Laer, J.V.; Faisal, N.; Egizabal, A.; Elizetxea, Cristina; Nelissen, I.; Blazquez, M.; Njuguna, J.; Elizextea, C.; Biomateriales; POLIMEROSIn this study, the effect on nanoparticle emissions due to drilling on Polypropylene (PP) reinforced with 20% talc, 5% montmorillonite (MMT) and 5% Wollastonite (WO) is investigated. The study is the first to explore the nanoparticle release from WO and talc reinforced composites and compares the results to previously researched MMT. With 5% WO, equivalent tensile properties with a 10 % weight reduction were obtained relative to the reference 20% talc sample. The materials were fabricated through injection moulding. The nanorelease studies were undertaken using the controlled drilling methodology for nanoparticle exposure assessment developed within the European Commission funded SIRENA Life 11 ENV/ES/506 project. Measurements were taken using CPC and DMS50 equipment for real-time characterization and measurements. The particle number concentration (of particles <1000nm) and particle size distribution (4.87nm - 562.34nm) of the particles emitted during drilling were evaluated to investigate the effect of the silicate fillers on the particles released. The nano-filled samples exhibited a 33% decrease (MMT sample) or a 30% increase (WO sample) on the average particle number concentration released in comparison to the neat polypropylene sample. The size distribution data displayed a substantial percentage of the particles released from the PP, PP/WO and PP/MMT samples to be between 5-20nm, whereas the PP/talc sample emitted larger particle diameters.Item Exposure to graphene in a pilot production plant(2019-10-17) Vaquero, C.; Wendelbo, R.; Egizabal, A.; Gutierrez-Cañas, C.; López de Ipiña, J.; PRINTEX; Biomateriales; SMART_MONWorkers exposure to graphene was measured in a pilot production plant. Reduced graphene oxide was produced through graphite oxidation and posterior thermal reduction. The monitoring was performed using two handheld on-line devices covering the particle size range from 10 nm to 10 μm (CPC3007 and OPS3330). Simultaneously, personal and area filter samples were collected for off line analysis, including gravimetric, elemental carbon analysis and SEM/EDX. Significant releases of particles were identified in two tasks, during the graphene oxide washing, and during its milling. However, the analysis of the particles size distribution and of their morphology suggested that the released particles were not the target nanomaterial but engine generated nanoparticles. The mass of elemental carbon in the collected filters was below the quantification limit and the calculated graphene mass concentrations were quite below the selected reference exposure limit. Overall, this work showed that worker exposure to graphene was low in this pilot plant, contributing to guarantee a safe process, prior to its industrialization.Item New trends on EAF slags management in the Basque Country(2000) Ortiz de Urbina, G.; Egizabal, A.; San Martín, R.; Tecnalia Research & Innovation; Biomateriales700,000 tonnes of primary slags are generated each year in the 13 steel plants located in the Basque Country, a small region of 20,664 Km2. Nowadays, as there is not Spanish regulation concerning environmental aspects related to the utilization of wastes, this great amount of waste is being landfilled. In order to solve environmental problems due to this kind of waste management a two years project covering the environmental aspects related to steel slags reutilization as a construction material was carried out. Results derived from the project have lead to a final draft of a Decree about steel slags reutilization as a construction material.Item On the experimental approaches for the assessment of the release of engineered nanomaterials from nanocomposites by physical degradation processes(2014) Blázquez, M.; Egizabal, A.; Unzueta, I.; BiomaterialesThe LIFE+ Project SIRENA, Simulation of the release of nanomaterials from consumer products for environmental exposure assessment, (LIFE11 ENV/ES/596) has set up a Technological Surveillance System (TSS) to trace technical references at worldwide level related to nanocomposites and the release from nanocomposites. So far a total of seventy three items of different nature (from peer reviewed articles to presentations and contributions to congresses) have been selected and classified as "nanomaterials release simulation technologies". In present document, different approaches for the simulation of different life cycle stages through the physical degradation of polymer nanocomposites at laboratory scale are assessed. In absence of a reference methodology, the comparison of the different protocols used still remains a challenge.Item Producción biológica de hidrógeno a partir de residuos(2004-06) Valero, J. M.; Egizabal, A.; Arrillaga, I.; Belsue, M.; Dirección General; Biomateriales; Tecnalia Research & InnovationItem Producción de hidrógeno a partir de residues mediante fermentación(2005-04) López, E.; Arrien, N.; Antoñanzas, J.; Egizabal, A.; Belsue, M.; Valero, J. M.; VALORIZACIÓN DE RESIDUOS; Biomateriales; Tecnalia Research & Innovation; Dirección GeneralItem Toxicogenomics study of nanomaterials on the model organism zebrafish(2007) Rojo, I.; Uriarte, M.; Obieta, I.; Bustero, I.; Egizabal, A.; Pardo, M. A.; De Martínez Ilárduya, O.; Tecnalia Research & Innovation; PRINTEX; BiomaterialesWe have adapted an "in vitro" toxicity test using zebrafish embryos for a toxicogenomics approach. Our goal is to develop a rapid toxicity assay for nanoparticles to be used in food and other applications. We incubated fertilized fish eggs for 48 h in the presence of a solution of purified MWCNT (1 ppb to 10 ppm) or with nanosilver solutions (1 ppb to 5 ppm). We could not detect effects on development or timing. We have used quantitative RT-PCR to analyze the expression patterns of Cyp1A1, Ahr2, Cpt1, iNOS, Ncf1, NudT1, c/EBP-a and MafT. These genes are involved in detoxification patterns, in the protection against oxidative stress or code for regulatory factors involved in the immune response. At these concentrations, nanosilver had clear effects on the expression of most of the genes in a dose dependant manner. Induction was maximum in the case of regulatory factors. On the contrary, changes in gene expression induced by MWCNTs were much lower, suggesting a reduced toxicity at the tested concentrations.