Oxalic acid-assisted preparation of LTO-carbon composite anode material for lithium-ion batteries.

This study presents an oxalic acid-assisted method for synthesizing spinel-structured lithium titanate (Li4Ti5O12; LTO)/carbon composite materials. The Ag-doped LTO nanoparticles (NPs) are synthesized via flame spray pyrolysis (FSP). The synthesized material is used as a precursor for synthesizing the LTO-NP/C composite material with chitosan as a carbon source and oxalic acid as an additive. Oxalic acid improves the dissolution of chitosan in water as well as changes the composition and physical and chemical properties of the synthesized LTO-NP/C composite material. The oxalic acid/chitosan ratio can be optimized to improve the electrochemical performance of the LTO-NP/C composite material, and the electrode synthesized with a high mass loading ratio (5.44 mg cm-2) exhibits specific discharge capacities of 156.5 and 136 mAh g-1at 0.05 C- and 10 C-rate currents, respectively. Moreover, the synthesized composite LTO-NP/C composite material exhibits good cycling stability, and only 1.7% decrease in its specific capacity was observed after 200 charging-discharging cycles at 10 C-rate discharging current.

Brown Coal and Logwood Combustion in a Modern Heating Appliance: The Impact of Combustion Quality and Fuel on Organic Aerosol Composition.

Residential heating with solid fuels is one of the major drivers for poor air quality in Central and Eastern Europe, and coal is still one of the major fuels in countries, such as Poland, the Czech Republic, and Hungary. In this work, emissions from a single-room heater fueled with brown coal briquettes (BCBs) and spruce logs (SLs) were analyzed for signatures of inorganic as well as semivolatile aromatic and low-volatile organic constituents. High variations in organic carbon (OC) emissions of BCB emissions, ranging from 5 to 22 mg MJ-1, were associated to variations in carbon monoxide (CO) emissions, ranging from 900 to 1900 mg MJ-1. Residential BCB combustion turned out to be an equally important source of levoglucosan, an established biomass burning marker, as spruce logwood combustion, but showed distinct higher ratios to manosan and galactosan. Signatures of polycyclic aromatic hydrocarbons emitted by BCB combustion exhibited defunctionalization and desubstitution with increasing combustion quality. Lastly, the concept of island and archipelago structural motifs adapted from petroleomics is used to describe the fraction low-volatile organic compounds in particulate emissions, where a transition from archipelago to island motifs in relation with decreasing CO emissions was observed in BCB emissions, while emissions from SL combustion exhibited the island motif.

Inflammatory responses of urban air PM modulated by chemical composition and different air quality situations in Nanjing, China.

The health risks of air pollutants and ambient particulate matter (PM) are widely known. PM composition and toxicity have shown substantial spatiotemporal variability. Yet, the connections between PM composition and toxicological and health effects are vaguely understood. This is a crucial gap in knowledge that needs to be addressed in order to establish air quality guidelines and limit values that consider the chemical composition of PM instead of the current assumption of equal toxicity per inhaled dose. Here, we demonstrate further evidence for varying toxicological effects of urban PM at equal mass concentrations, and estimate how PM composition and emission source characteristics influenced this variation. We exposed a co-culture model mimicking alveolar epithelial cells and macrophages with size-segregated urban ambient PM collected before, during, and after the Nanjing Youth Olympic Games 2014. We measured the release of a set of cytokines, cell cycle alterations, and genotoxicity, and assessed the spatiotemporal variations in these responses by factorial multiple regression analysis. Additionally, we investigated how a previously identified set of emission sources and chemical components affected these variations by mixed model analysis. PM-exposure induced cytokine signaling, most notably by inducing dose-dependent increases of macrophage-regulating GM-CSF and proinflammatory TNFα, IL-6, and IL-1ß concentrations, modest dose-dependent increase for cytoprotective VEGF-A, but very low to no responses for anti-inflammatory IL-10 and immunoregulatory IFNγ, respectively. We observed substantial differences in proinflammatory cytokine production depending on PM sampling period, location, and time of day. The proinflammatory response correlated positively with cell cycle arrest in G1/G0 phase and loss of cellular metabolic activity. Furthermore, PM0.2 caused dose-dependent increases in sub-G1/G0 cells, suggesting increased DNA degradation and apoptosis. Variations in traffic and oil/fuel combustion emissions contributed substantially to the observed spatiotemporal variations of toxicological responses.

Influence of induction-annealing temperature on the morphology of barley-straw-derived Si@C and SiC@graphite for potential application in Li-ion batteries.

Silicon, a material with high theoretical energy density, holds great promise as a candidate material for anodes in lithium-ion batteries. However, due to an alloying mechanism the material undergoes volume expansion of up to 300%, which results in rapid capacity fading. The coating of silicon with carbon is done by using a biomass-based carbon precursor. The effects of annealing temperature on the morphology of the silicon-carbon structures is presented herein. The mechanically and chemically treated barley straw is mixed with silicon particles and induction annealed in argon atmosphere under different temperatures. The material transformation from carbon-coated silicon (Si@C) to graphite-coated silicon carbide (SiC@graphite) is studied. The Si@C displayed initial specific capacity of 1200 mAh g-1 at 0.1 A g-1, while the capacity retention analysis of Si@C revealed improved cycling stability compared to bare silicon.

Air quality intervention during the Nanjing youth olympic games altered PM sources, chemical composition, and toxicological responses.

Ambient particulate matter (PM) is a leading global environmental health risk. Current air quality regulations are based on airborne mass concentration. However, PM from different sources have distinct chemical compositions and varied toxicity. Connections between emission control measures, air quality, PM composition, and toxicity remain insufficiently elucidated. The current study assessed the composition and toxicity of PM collected in Nanjing, China before, during, and after an air quality intervention for the 2014 Youth Olympic Games. A co-culture model that mimics the alveolar epithelium with the associated macrophages was created using A549 and THP-1 cells. These cells were exposed to size-segregated inhalable PM samples. The composition and toxicity of the PM samples were influenced by several factors including seasonal variation, emission sources, and the air quality intervention. For example, we observed a size-dependent shift in particle mass concentrations during the air quality intervention with an emphasized proportion of smaller particles (PM2.5) present in the air. The roles of industrial and fuel combustion and traffic emissions were magnified during the emission control period. Our analyses revealed that the PM samples demonstrated differential cytotoxic potencies at equal mass concentrations between sampling periods, locations, and time of day, influenced by variations in the predominant emission sources. Coal combustion and industrial emissions were the most important sources affecting the toxicological responses and displayed the least variation in emission contributions between the sampling periods. In conclusion, emission control mitigated cytotoxicity and oxidative stress for particles larger than 0.2 µm, but there was inadequate evidence to determine if it was the key factor reducing the harmful effects of PM0.2.

Influence of wood species on toxicity of log-wood stove combustion aerosols: a parallel animal and air-liquid interface cell exposure study on spruce and pine smoke.

BACKGROUND: Wood combustion emissions have been studied previously either by in vitro or in vivo models using collected particles, yet most studies have neglected gaseous compounds. Furthermore, a more accurate and holistic view of the toxicity of aerosols can be gained with parallel in vitro and in vivo studies using direct exposure methods. Moreover, modern exposure techniques such as air-liquid interface (ALI) exposures enable better assessment of the toxicity of the applied aerosols than, for example, the previous state-of-the-art submerged cell exposure techniques. METHODS: We used three different ALI exposure systems in parallel to study the toxicological effects of spruce and pine combustion emissions in human alveolar epithelial (A549) and murine macrophage (RAW264.7) cell lines. A whole-body mouse inhalation system was also used to expose C57BL/6 J mice to aerosol emissions. Moreover, gaseous and particulate fractions were studied separately in one of the cell exposure systems. After exposure, the cells and animals were measured for various parameters of cytotoxicity, inflammation, genotoxicity, transcriptome and proteome. RESULTS: We found that diluted (1:15) exposure pine combustion emissions (PM1 mass 7.7 ± 6.5 mg m- 3, 41 mg MJ- 1) contained, on average, more PM and polycyclic aromatic hydrocarbons (PAHs) than spruce (PM1 mass 4.3 ± 5.1 mg m- 3, 26 mg MJ- 1) emissions, which instead showed a higher concentration of inorganic metals in the emission aerosol. Both A549 cells and mice exposed to these emissions showed low levels of inflammation but significantly increased genotoxicity. Gaseous emission compounds produced similar genotoxicity and a higher inflammatory response than the corresponding complete combustion emission in A549 cells. Systems biology approaches supported the findings, but we detected differing responses between in vivo and in vitro experiments. CONCLUSIONS: Comprehensive in vitro and in vivo exposure studies with emission characterization and systems biology approaches revealed further information on the effects of combustion aerosol toxicity than could be achieved with either method alone. Interestingly, in vitro and in vivo exposures showed the opposite order of the highest DNA damage. In vitro measurements also indicated that the gaseous fraction of emission aerosols may be more important in causing adverse toxicological effects. Combustion aerosols of different wood species result in mild but aerosol specific in vitro and in vivo effects.

Spray deposition and characterization of carbon nanoflower and gold-doped carbon nanoflower thin films.

Herein, we present an aerosol filtration method for the fabrication of carbon nanoflower (CNF) thin films. The method was based on generation, evaporation and filtration of solvent encapsulated CNF droplets. The particles were collected on polytetrafluoroethylene membranes and roll-transferred at room temperature onto flexible polyethylene terephthalate substrates. Suspensions for spraying were made in low vapor pressure mixtures of EtOH/Hex (50/50 v/v%). Doping of starter suspensions was made by the addition of organometallic 1-dodecanethiol-coated gold nanoparticles (AuNPs). The produced films displayed substrate surface coverage of up to 83.3% ± 13.9% and a film thickness of up to 2.4 µm. The deposition of doped suspensions resulted in uniform distribution of AuNPs in the volume of the CNF film, which enables film application for flexible photovoltaics.

Volatile Organic Compounds from Logwood Combustion: Emissions and Transformation under Dark and Photochemical Aging Conditions in a Smog Chamber.

Residential wood combustion (RWC) emits high amounts of volatile organic compounds (VOCs) into ambient air, leading to formation of secondary organic aerosol (SOA), and various health and climate effects. In this study, the emission factors of VOCs from a logwood-fired modern masonry heater were measured using a Proton-Transfer-Reactor Time-of-Flight Mass Spectrometer. Next, the VOCs were aged in a 29 m3 Teflon chamber equipped with UV black lights, where dark and photochemical atmospheric conditions were simulated. The main constituents of the VOC emissions were carbonyls and aromatic compounds, which accounted for 50%-52% and 30%-46% of the detected VOC emission, respectively. Emissions were highly susceptible to different combustion conditions, which caused a 2.4-fold variation in emission factors. The overall VOC concentrations declined considerably during both dark and photochemical aging, with simultaneous increase in particulate organic aerosol mass. Especially furanoic and phenolic compounds decreased, and they are suggested to be the major precursors of RWC-originated SOA in all aging conditions. On the other hand, dark aging produced relatively high amounts of nitrogen-containing organic compounds in both gas and particulate phase, while photochemical aging increased especially the concentrations of certain gaseous carbonyls, particularly acid anhydrides.

Effect of Pellet Boiler Exhaust on Secondary Organic Aerosol Formation from α-Pinene.

Interactions between anthropogenic and biogenic emissions, and implications for aerosol production, have raised particular scientific interest. Despite active research in this area, real anthropogenic emission sources have not been exploited for anthropogenic-biogenic interaction studies until now. This work examines these interactions using α-pinene and pellet boiler emissions as a model test system. The impact of pellet boiler emissions on secondary organic aerosol (SOA) formation from α-pinene photo-oxidation was studied under atmospherically relevant conditions in an environmental chamber. The aim of this study was to identify which of the major pellet exhaust components (including high nitrogen oxide (NOx), primary particles, or a combination of the two) affected SOA formation from α-pinene. Results demonstrated that high NOx concentrations emitted by the pellet boiler reduced SOA yields from α-pinene, whereas the chemical properties of the primary particles emitted by the pellet boiler had no effect on observed SOA yields. The maximum SOA yield of α-pinene in the presence of pellet boiler exhaust (under high-NOx conditions) was 18.7% and in the absence of pellet boiler exhaust (under low-NOx conditions) was 34.1%. The reduced SOA yield under high-NOx conditions was caused by changes in gas-phase chemistry that led to the formation of organonitrate compounds.

Particulate emissions from the combustion of birch, beech, and spruce logs cause different cytotoxic responses in A549 cells.

According to the World Health Organization particulate emissions from the combustion of solid fuels caused more than 110,000 premature deaths worldwide in 2010. Log wood combustion is the most prevalent form of residential biomass heating in developed countries, but it is unknown how the type of wood logs used in furnaces influences the chemical composition of the particulate emissions and their toxicological potential. We burned logs of birch, beech and spruce, which are used commonly as firewood in Central and Northern Europe in a modern masonry heater, and compared them to the particulate emissions from an automated pellet boiler fired with softwood pellets. We determined the chemical composition (elements, ions, and carbonaceous compounds) of the particulate emissions with a diameter of less than 1 µm and tested their cytotoxicity, genotoxicity, inflammatory potential, and ability to induce oxidative stress in a human lung epithelial cell line. The chemical composition of the samples differed significantly, especially with regard to the carbonaceous and metal contents. Also the toxic effects in our tested endpoints varied considerably between each of the three log wood combustion samples, as well as between the log wood combustion samples and the pellet combustion sample. The difference in the toxicological potential of the samples in the various endpoints indicates the involvement of different pathways of toxicity depending on the chemical composition. All three emission samples from the log wood combustions were considerably more toxic in all endpoints than the emissions from the pellet combustion. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1487-1499, 2017.

Untargeted Identification of Wood Type-Specific Markers in Particulate Matter from Wood Combustion.

Residential wood combustion emissions are one of the major global sources of particulate and gaseous organic pollutants. However, the detailed chemical compositions of these emissions are poorly characterized due to their highly complex molecular compositions, nonideal combustion conditions, and sample preparation steps. In this study, the particulate organic emissions from a masonry heater using three types of wood logs, namely, beech, birch, and spruce, were chemically characterized using thermal desorption in situ derivatization coupled to a GCxGC-ToF/MS system. Untargeted data analyses were performed using the comprehensive measurements. Univariate and multivariate chemometric tools, such as analysis of variance (ANOVA), principal component analysis (PCA), and ANOVA simultaneous component analysis (ASCA), were used to reduce the data to highly significant and wood type-specific features. This study reveals substances not previously considered in the literature as meaningful markers for differentiation among wood types.

Reference particles for toxicological studies of wood combustion: formation, characteristics, and toxicity compared to those of real wood combustion particulate mass.

Multiple studies show that particulate mass (PM) generated from incomplete wood combustion may induce adverse health issues in humans. Previous findings have shown that also the PM from efficient wood combustion may induce enhanced production of reactive oxygen species (ROS), inflammation, and cytotoxicity in vitro and in vivo. Underlying factors of these effects may be traced back to volatile inorganic transition metals, especially zinc, which can be enriched in the ultrafine fraction of biomass combustion particulate emission. In this study, nanoparticles composed of potassium, sulfur, and zinc, which are the major components forming inorganic fine PM, were synthesized and tested in vitro. In addition, in vitro toxicity of PM from efficient combustion of wood chips was compared with that of the synthesized particles. Cytotoxicity, cell cycle arrest, ROS generation, and tumor necrosis factor alpha release were related to zinc concentration in PM. Potassium sulfate and potassium carbonate did not induce toxic responses. In light of the provided data, it can be concluded that zinc, enriched in wood combustion emissions, caused the toxicity in all of the measured end points.

Effective density and morphology of particles emitted from small-scale combustion of various wood fuels.

The effective density of fine particles emitted from small-scale wood combustion of various fuels were determined with a system consisting of an aerosol particle mass analyzer and a scanning mobility particle sizer (APM-SMPS). A novel sampling chamber was combined to the system to enable measurements of highly fluctuating combustion processes. In addition, mass-mobility exponents (relates mass and mobility size) were determined from the density data to describe the shape of the particles. Particle size, type of fuel, combustion phase, and combustion conditions were found to have an effect on the effective density and the particle shape. For example, steady combustion phase produced agglomerates with effective density of roughly 1 g cm(-3) for small particles, decreasing to 0.25 g cm(-3) for 400 nm particles. The effective density was higher for particles emitted from glowing embers phase (ca. 1-2 g cm(-3)), and a clear size dependency was not observed as the particles were nearly spherical in shape. This study shows that a single value cannot be used for the effective density of particles emitted from wood combustion.

Optical and chemical characterization of aerosols emitted from coal, heavy and light fuel oil, and small-scale wood combustion.

Particle emissions affect radiative forcing in the atmosphere. Therefore, it is essential to know the physical and chemical characteristics of them. This work studied the chemical, physical, and optical characteristics of particle emissions from small-scale wood combustion, coal combustion of a heating and power plant, as well as heavy and light fuel oil combustion at a district heating station. Fine particle (PM1) emissions were the highest in wood combustion with a high fraction of absorbing material. The emissions were lowest from coal combustion mostly because of efficient cleaning techniques used at the power plant. The chemical composition of aerosols from coal and oil combustion included mostly ions and trace elements with a rather low fraction of absorbing material. The single scattering albedo and aerosol forcing efficiency showed that primary particles emitted from wood combustion and some cases of oil combustion would have a clear climate warming effect even over dark earth surfaces. Instead, coal combustion particle emissions had a cooling effect. Secondary processes in the atmosphere will further change the radiative properties of these emissions but are not considered in this study.

Role of microbial and chemical composition in toxicological properties of indoor and outdoor air particulate matter.

BACKGROUND: Ambient air particulate matter (PM) is increasingly considered to be a causal factor evoking severe adverse health effects. People spend the majority of their time indoors, which should be taken into account especially in future risk assessments, when the role of outdoor air particles transported into indoor air is considered. Therefore, there is an urgent need for characterization of possible sources seasonally for harmful health outcomes both indoors and outdoors. METHODS: In this study, we collected size-segregated (PM(10-2.5), PM(2.5-0.2)) particulate samples with a high volume cascade impactor (HVCI) simultaneously both indoors and outdoors of a new single family detached house at four different seasons. The chemical composition of the samples was analyzed as was the presence of microbes. Mouse macrophages were exposed to PM samples for 24 hours. Thereafter, the levels of the proinflammatory cytokines, NO-production, cytotoxicity and changes in the cell cycle were investigated. The putative sources of the most toxic groups of constituents were resolved by using the principal component analysis (PCA) and pairwise dependencies of the variables were detected with Spearman correlation. RESULTS: Source-related toxicological responses clearly varied according to season. The role of outdoor sources in indoor air quality was significant only in the warm seasons and the significance of outdoor microbes was also larger in the indoor air. During wintertime, the role of indoor sources of the particles was more significant, as was also the case for microbes. With respect to the outdoor sources, soil-derived particles during a road dust episode and local wood combustion in wintertime were the most important factors inducing toxicological responses. CONCLUSIONS: Even though there were clear seasonal differences in the abilities of indoor and outdoor air to induce inflammatory and cytotoxic responses, there were relatively small differences in the chemical composition of the particles responsible of those effects. Outdoor sources have only a limited effect on indoor air quality in a newly built house with a modern ventilation system at least in a low air pollution environment. The most important sources for adverse health related toxicological effects were related to soil-derived constituents, local combustion emissions and microbes.

Toxicological properties of emission particles from heavy duty engines powered by conventional and bio-based diesel fuels and compressed natural gas.

BACKGROUND: One of the major areas for increasing the use of renewable energy is in traffic fuels e.g. bio-based fuels in diesel engines especially in commuter traffic. Exhaust emissions from fossil diesel fuelled engines are known to cause adverse effects on human health, but there is very limited information available on how the new renewable fuels may change the harmfulness of the emissions, especially particles (PM). We evaluated the PM emissions from a heavy-duty EURO IV diesel engine powered by three different fuels; the toxicological properties of the emitted PM were investigated. Conventional diesel fuel (EN590) and two biodiesels were used - rapeseed methyl ester (RME, EN14214) and hydrotreated vegetable oil (HVO) either as such or as 30% blends with EN590. EN590 and 100% HVO were also operated with or without an oxidative catalyst (DOC + POC). A bus powered by compressed natural gas (CNG) was included for comparison with the liquid fuels. However, the results from CNG powered bus cannot be directly compared to the other situations in this study. RESULTS: High volume PM samples were collected on PTFE filters from a constant volume dilution tunnel. The PM mass emission with HVO was smaller and with RME larger than that with EN590, but both biofuels produced lower PAH contents in emission PM. The DOC + POC catalyst greatly reduced the PM emission and PAH content in PM with both HVO and EN590. Dose-dependent TNFα and MIP-2 responses to all PM samples were mostly at the low or moderate level after 24-hour exposure in a mouse macrophage cell line RAW 264.7. Emission PM from situations with the smallest mass emissions (HVO + cat and CNG) displayed the strongest potency in MIP-2 production. The catalyst slightly decreased the PM-induced TNFα responses and somewhat increased the MIP-2 responses with HVO fuel. Emission PM with EN590 and with 30% HVO blended in EN590 induced the strongest genotoxic responses, which were significantly greater than those with EN590 + cat or 100% HVO. The emission PM sample from the CNG bus possessed the weakest genotoxic potency but had the strongest oxidative potency of all the fuel and catalyst combinations. The use of 100% HVO fuel had slightly weaker and 100% RME somewhat stronger emission PM induced ROS production, when compared to EN590. CONCLUSIONS: The harmfulness of the exhaust emissions from vehicle engines cannot be determined merely on basis of the emitted PM mass. The study conditions and the engine type significantly affect the toxicity of the emitted particles. The selected fuels and DOC + POC catalyst affected the PM emission from the heavy EURO IV engine both qualitative and quantitative ways, which influenced their toxicological characteristics. The plain HVO fuel performed very well in emission reduction and in lowering the overall toxicity of emitted PM, but the 30% blend of HVO in EN590 was no better in this respect than the plain EN590. The HVO with a DOC + POC catalyst in the EURO IV engine, performed best with regard to changes in exhaust emissions. However some of the toxicological parameters were significantly increased even with these low emissions.

Acute systemic and lung inflammation in C57Bl/6J mice after intratracheal aspiration of particulate matter from small-scale biomass combustion appliances based on old and modern technologies.

Inflammation is regarded as an important mechanism behind mortality and morbidity experienced by cardiorespiratory patients exposed to urban air particulate matter (PM). Small-scale biomass combustion is an important source of particulate air pollution. In this study, we investigated association between inflammatory responses and chemical composition of PM(1) emissions from seven different small-scale wood combustion appliances representing old and modern technologies. Healthy C57Bl/6J mice were exposed by intratracheal aspiration to single dose (10 mg/kg) of particulate samples. At 4 and 18 h after the exposure, bronchoalveolar lavage fluid (BALF) as well as serum was collected for subsequent analyses of inflammatory indicators (interleukin (IL)-6, IL-1ß, IL-12, and IL-10; tumor necrosis factor-α (TNF-α); keratinocyte-derived chemoattractant (KC), and interferon-γ (IFN-γ)) in multiplexing assay. When the responses to the PM(1) samples were compared on an equal mass basis, the PM from modern technology appliances increased IL-6, KC, and IL-1ß levels significantly in BALF at 4 and 18 h after the exposure. In contrast, these responses were seen only at 4 h time point in serum. Increased cytokine concentrations correlated with metal-rich ash related compounds which were more predominant in the modern technology furnaces emissions. These particles induced both local and systemic inflammation. Instead, polycyclic hydrocarbon (PAH) rich PM(1) samples from old technology (OT) evoked only minor inflammatory responses. In conclusion, the combustion technology largely affects the toxicological and chemical characteristics of the emissions. The large mass emissions of old combustion technology should be considered, when evaluating the overall harmfulness between the appliances. However, even the small emissions from modern technologies may pose significant toxic risks.

Efficiency of log wood combustion affects the toxicological and chemical properties of emission particles.

CONTEXT: Particulate matter (PM) has been identified as a major environmental pollutant causing severe health problems. Large amounts of the harmful particulate matter (PM) are emitted from residential wood combustion, but the toxicological properties of wood combustion particles are poorly known. OBJECTIVE: To investigate chemical and consequent toxicological characteristics of PM(1) emitted from different phases of batch combustion in four heating appliances. MATERIALS AND METHODS: Mouse RAW264.7 macrophages and human BEAS-2B bronchial epithelial cells were exposed for 24 h to different doses (15-300 µg/mL) of wood combustion particles. After the exposure, cytotoxicity, genotoxicity, production of the inflammatory mediators (TNF-α and MIP-2) and effects on the cell cycle were assessed. Furthermore, the detected toxicological responses were compared with the chemical composition of PM(1) samples including PAHs, metals and ions. RESULTS: All the wood combustion samples exerted high cytotoxicity, but only moderate inflammatory activity. The particles emitted from the inefficient phase of batch combustion in the sauna stove (SS) induced the most extensive cytotoxic and genotoxic responses in mammalian cells. Polycyclic aromatic hydrocarbons (PAHs) and other organic compounds in PM(1) samples might have contributed to these effects. Instead, water-soluble metals seemed to participate in the cytotoxic responses triggered by the particles from more efficient batch combustion in the masonry heaters. Overall, the toxicological responses were decreased when the combustion phase was more efficient. CONCLUSION: Efficiency of batch combustion plays a significant role in the harmfulness of PM even under incomplete wood combustion processes.

[Nanoscale tailoring of the surface properties of biomaterials and drug carriers]. / Nanoteknologia biomateriaalien ja lääkkeiden kantaja-aineiden pintojen räätälöinnissä.

Functionalities of biomaterials and drug delivery systems are improved by tailoring their surface properties using modern nanotechnology. Orthopedic implants and invasive electrodes are examples of implantable biomaterials. Biological interactions of orthopedic implants can be optimized by the synergetic effect of surface micro- and nanotexturing with a chemical composition of coating. Further, mechanical flexibility and electrochemical characteristics of invasive electrodes are improved by using micro- and nanotechnology. In nano-size drug delivery systems, surface properties of nanocarriers strongly affect their safety and efficacy. Mesoporous silicon nanoparticles are example of nanocarriers those properties can be tailored for drug delivery applications.

Genotoxic and inflammatory effects of spruce and brown coal briquettes combustion aerosols on lung cells at the air-liquid interface.

Solid fuel usage in residential heating and cooking is one of the largest sources of ambient and indoor air particulate matter, which causes adverse effects on the health of millions of peoples worldwide. Emissions from solid fuel combustion, such as biomass or coal, are detrimental to health, but toxicological responses are largely unknown. In the present study, we compared the toxicological responses regarding cytotoxicity, inflammation and genotoxicity of spruce (SPR) and brown coal briquette (BCB) combustion aerosols on human alveolar epithelial cells (A549) as well as a coculture of A549 and differentiated human monocytic cells (THP-1) into macrophages exposed at the air-liquid interface (ALI). We included both the high emissions from the first hour and moderate emissions from the third hour of the batch combustion experiment in one ALI system, whereas, in the second ALI system, we exposed the cells during the whole 4-hour combustion experiment, including all combustion phases. Physico-chemical properties of the combustion aerosol were analysed both online and offline. Both SPR and BCB combustion aerosols caused mild cytotoxic but notable genotoxic effects in co-cultured A549 cells after one-hour exposure. Inflammatory response analysis revealed BCB combustion aerosols to cause a mild increase in CXCL1 and CXCL8 levels, but in the case of SPR combustion aerosol, a decrease compared to control was observed.