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The recycling of fly ash from municipal solid waste incineration is currently a global issue. This work intends to examine the viability of a novel recycling alternative for fly ashes as a component of fire-resistant plates. To lessen the quantity of heavy metal leaching, the fly ash was utilized after being washed using a water/fly ash ratio of 2 for one hour. Subsequently, an inexpensive, straightforward molding and curing process was used to create a plate, with a composition of 60%wt of MSWI-FA, 30%wt of gypsum, 0.5%wt of glass fiber and 9.5%wt of vermiculite. The plate exhibited high fire resistance. Furthermore, it demonstrated compression, flexural strength and surface hardness slightly lower than the requirements of European Standards. This allows for manufacturing plates with a high washed MSWI-FA content as fire protection in firewalls and doors for homes and commercial buildings. A Life Cycle Assessment was carried out. The case study shows that a 60% substitution of gypsum resulted in an environmental impact reduction of 8-48% for all impact categories examined, except four categories impacts (marine eutrophication, human toxicity (cancer), human non-carcinogenic toxicity and water depletion, where it increased between 2 and 718 times), due to the previous washing of MSWI-FA. When these fly ashes are used as a raw material in fire-resistant materials, they may be recycled and offer environmental advantages over more conventional materials like gypsum.

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Mercury (Hg) emissions from forest fires, especially tropical forests such as the Amazonian forest, were shown to contribute significantly to the atmospheric mercury budget, but new methods are still necessary to improve the traceability and to reduce the great uncertainties related to this emission source. Recent studies have shown that the combustion process can result in Hg stable isotope fractionation that allows tracking coal combustion Hg emissions, as influenced by different factors such as combustion temperature. The main goal of the present study was, therefore, to investigate for the first time the potential of Hg stable isotopes to trace forest fire Hg emissions and pathways. More specifically, small-scale and a large scale prescribed forest fire experiments were conducted in the Brazilian Amazonian forest to study the impact of fire severity on Hg isotopic composition of litter, soil, and ash samples and associated Hg isotope fractionation pathways. In the small-scale experiment, no difference was found in the mercury isotopic composition of the samples collected before and after burning. In contrast, the larger-scale experiment resulted in significant mass dependent fractionation (MDF δ202Hg) in soils and ash suggesting that higher combustion temperature influence Hg isotopic fractionation with the emission of lighter Hg isotopes to the atmosphere and enrichment with heavier Hg in ashes. As for coal combustion, mass independent fractionation was not observed. To our knowledge, these results are the first to highlight the potential of forest fires to cause Hg isotopic fractionation, depending on the fire severity. The results also allowed to establish an isotopic fingerprint for tropical forest fire Hg emissions that corresponds to a mixture of litter and soil Hg isotopic composition (resulting atmospheric δ202Hg, Δ200Hg and Δ199Hg were -1.79 ± 0.24‰, -0.05 ± 0.04‰ and -0.45 ± 0.12‰, respectively).

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High phosphate concentrations in natural waters are associated with eutrophication problems that negatively affect the fauna and flora of ecosystems. As an alternative solution to this problem, we evaluated the adsorptive capacity of the fruit peel ash (PPA) of Caryocar coriaceum Wittm and its efficiency in removing phosphate (PO43-) from aqueous solutions. PPA was produced under an oxidative atmosphere and calcinated at 500 °C. The XRF and EDS analyses of PPA after contact with an aqueous PO43- solution showed an increase in its PO43- content, thus confirming the adsorption of PO43-. The Elovich and Langmuir models are the ones fitting the kinetics and the equilibrium state of the process, respectively. The highest PO43- adsorption capacity was approximately 79.50 mg g-1 at 10 °C. PO43- adsorption by PPA is a spontaneous, favorable, and endothermic process involving structural changes. The highest removal efficiency was 97.08% using a 100 mg.L-1 PO43- solution. In sight of this, PPA has shown potential as an excellent natural bioadsorbent.

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The remarkable properties of garlic A. sativum L. have been described, but little is known about Snow mountain garlic. Understanding general aspects of this garlic composition, including the presence of phenolics, will establish its possible use for health or infer which compounds can contribute to improving it. This study aimed to determine the ash content, lipid profile, and characterization of phenolics in Snow mountain garlic. The organic content was obtained by common techniques (oven drying, calcination, Kjeldahl method, etc.). The quantitative analysis of the ashes was made by Inductively Coupled Plasma Emission Spectrometry. The fatty acid profile was determined by Gas Chromatography. The presence of phenolics was determined by foam, Libermann-Burchard, Dragendorff, Salkowski, ferric chloride, vanillin, catechin, Constantinescu, and Shinoda reactions. The total phenolic content was determined via the Folin-Ciocalteu method, and antioxidant activity was determined using the DPPH radical method. The bromatological analysis showed a 51.1% humidity, and the main organic compounds were carbohydrates (46.7%). Ash analysis showed 287.46 g/kg of potassium. The fatty acid profile showed 75.61% of polyunsaturated fatty acid. Phenolics like saponins, alkaloids, triterpenes, tannins, and flavonoids were present. Antioxidant activity was found by radical DPPH of 25.64 (±0.78) µmol TE/1 g dw. Snow mountain garlic shares a composition similar to those found in other garlic.

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Preservative treatments increase the durability of wood, and one of the alternative treatments involves the use of chromated copper arsenate (CCA). Due to the toxicity of CCA, the disposal of CCA-treated wood residues is problematic, and burning is considered to provide a solution. The ecotoxicological potential of ash can be high when these components are toxic and mutagenic. The aim of this study was to evaluate the toxicity and genotoxicity of bottom ash leachates originating from CCA-treated wood burning. Physical-chemical analysis of the leachates revealed that in treated wood ashes leachate (CCA-TWBAL), the contents of arsenic and chromium were 59.45 mg.L-1 and 54.28 mg.L-1, respectively. In untreated wood ashes leachate (UWBAL), these contents were 0.70 mg.L-1 and 0.30 mg.L-1, respectively. CCA-TWBAL caused significant toxicity in Lactuca sativa, Allium cepa, and microcrustacean Artemia spp. (LC50 = 12.12 mg.mL-1). Comet assay analyses using NIH3T3 cells revealed that concentrations ranging from 1.0 and 2.5 mg.mL-1 increase the damage frequency (DF) and damage index (DI). According to MTT assay results, CCA-TWBAL at concentrations as low as 1 mg.mL-1 caused a significant decrease in cellular viability. Hemolysis assay analyses suggest that the arsenic and chromium leachate contents are important for the ecotoxic, cytotoxic, and genotoxic effects of CCA-TWBAL.

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A green methodology was developed for the analysis of ten heterocyclic aromatic amines (HAAs) in biomass samples from cigarette combustion such as mainstream smoke, paper ashes, as well as tobacco and paper wraps. The cellulose filter used for sample collection was also evaluated. This strategy was based on ultrasound-assisted extraction (UAE) associated with a solid-phase extraction procedure employing multi-walled carbon nanotubes (MWCNTs-SPE) as a cleanup step followed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Under optimal experimental conditions, the linearity of the method was in the range from 0.08 to 160 ng cig-1, with correlation coefficients (R2) higher than 0.991. The limits of detection resulted to be between 0.03 and 0.63 ng cig-1. Concentrations of the HAAs in the mainstream smoke were from 5.7 to 145.2 ng cig-1 and in paper ashes from 0.1 to 0.6 ng cig -1, while in tobacco were between 1.0 and 38.5 ng cig-1. Meanwhile, no HAA contribution was observed in the case of paper wraps and the filter used for sample collection. The knowledge of the presence and the concentration levels of the selected HAAs in each cigarette's physical component after its combustion is essential to understand the formation processes and contribution during cigarette burning. Besides, this is the first report about the presence of some HAAs in the proposed samples. Finally, a comparative study was employed to classify the sustainability of several recent approaches for HAA extraction from cigarette combustion samples using Green Certificate as a metric tool.

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The primary sludge produced by the wastewater treatment plant of a pulp and paper mill has high physicochemical heterogeneity, which limits the efficiency of thermochemical methodologies for the final disposal of this residue. As a solution, co-pelletization of the Primary Sludge (PS) with two other principal Industrial Solid Residues (ISRs) of the plant, Coal Boiler Ashes (CBA) and Wood Waste chips (WW), was proposed as a way to valorize the PS for energy use, while reducing dewatering costs. The energy potential was evaluated through a series of thermal co-processing tests of disaggregated and pelletized mixtures. Due to their differing fixed-carbon-to-volatile-material ratios, combining the ISRs resulted in a reduction of up to 45% of the mass of the ISR generated, improving the disposal conditions and achieving a minimum thermal power of 5.0 MJ/Nm3 through gasification. Finally, the environmental implications of the thermal co-processing of the wastes were assessed, finding very low impacts due to pollutant emissions, in accordance with the legal environmental regulations in force in Colombia.

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Resumen El cultivo de gramíneas y leguminosas con alto valor nutritivo para suplir los requerimientos nutricionales de los animales, es una alternativa para la reducción de costos en la producción animal. El objetivo del estudio fue caracterizar la calidad nutricional del ensilaje de forraje de quinua (Chenopodium quinoa willd) variedad amarilla de maranganí con adición de microorganismos eficientes en relación con la edad de la quinua y los diferentes periodos de fermentación del ensilaje. Se recolectó el material vegetal (hojas y tallos) de quinua, se evaluaron tres edades de corte: 60, 90 y 120 días y cuatro periodos de fermentación del ensilaje: siete, catorce, veinte uno y treinta días. Se realizaron 4 tratamientos: tratamiento 1 (T1) se refiere al control sin aplicar ningún tipo de EM, los tratamientos T2, T3 Y T4 se les aplicó EM a la dosis indicada en la etiqueta como aditivo para ensilajes, cada tratamiento se realizó por triplicado. El material vegetal se deshidrató durante un periodo de 5 horas y posteriormente se elaboraron los microsilos de follaje de quinua. se determinó el valor nutritivo (materia seca, fibra detergente neutra, fibra detergente acida, cenizas y proteína cruda) al follaje y a los microsilos de quinua. Se utilizó un diseño completamente al azar (DCA) con un arreglo de parcelas divididas en el tiempo, se hizo un análisis de varianza utilizando el Modelo Lineal mixto y una separación de medias por el método de Duncan y una correlación de variables de Pearson. Para la variable humedad se encontró un rango de 81,3 - 87,7% para el T1 y un rango de valores de 57,3 - 90,3% para los demás tratamientos. Las cenizas se mantuvieron en valores similares al follaje de quinua en relación a las diferentes edades de rebrote, el mayor porcentaje de cenizas se obtuvo a los 21 días de fermentación del ensilaje con un valor de 20,3% para el T3 con el ensilaje de follaje de quinua de 90 días de rebrote; mientras que el contenido de proteína cruda disminuyo ligeramente en relación al T1 en la edad de rebrote de los 120 días presentando variaciones significativas entre los tratamientos con valores de 11,3-17,3%. Se presentó una relación positiva perfecta directamente proporcional (P≤0,01) entre los promedios de FDA y FDN (r=0,975) para todos los tratamientos evaluados. La planta de quinua permitiría un uso multipropósito del cultivo, generando grano para el consumo humano y follaje para el consumo animal.

Abstract The cultivation of grasses and legumes with high nutritional value to meet the nutritional requirements of animals, is an alternative for reducing costs in animal production. The objective of the study was to characterize the nutritional quality of the quinoa silage (Chenopodium quinoa willd) yellow variety of marangani with the addition of efficient microorganisms in relation to the age of quinoa and the different periods of silage fermentation. The quinoa plant material (leaves and stems) was collected, three cutting ages were evaluated: 60, 90 and 120 days and four periods of silage fermentation: seven, fourteen, twenty one and thirty days. Four treatments were performed: treatment 1 (T1) refers to the control without applying any type of MS, treatments T2, T3 and T4 were applied MS at the dose indicated on the label as silage additive, each treatment was performed in triplicate . The plant material was dehydrated for a period of 5 hours and subsequently the quinoa foliage microsyls were made. The nutritional value (dry matter, neutral detergent fiber, acid detergent fiber, ash and crude protein) was determined to the foliage and quinoa microsilos. A completely randomized design (DCA) with an arrangement of time-divided plots was used, an analysis of variance was made using the Mixed Linear Model and a separation of means by the Duncan method and a correlation of Pearson variables. For the humidity variable, a range of 81,3 - 87,7% was found for T1 and a range of values of 57,3 - 90,3% for the other treatments. The ashes were maintained in values similar to the quinoa foliage in relation to the different ages of regrowth, the highest percentage of ashes was obtained at 21 days of silage fermentation with a value of 20,3% for T3 with the silage of Quinoa foliage 90 days of regrowth; while the crude protein content decreased slightly in relation to T1 in the 120-day regrowth age, presenting significant variations between treatments with values of 11,3-17,3%. A directly positive proportion directly proportional (P≤0,01) was presented between the FDA and FDN averages (r=0.975) for all the treatments evaluated. The quinoa plant would allow multipurpose use of the crop, generating grain for human consumption and foliage for animal consumption.

Resumo O cultivo de gramíneas e leguminosas com alto valor nutricional para suprir os requerimentos nutricionais dos animais, é uma alternativa para a redução de custos na produção animal. O objetivo do estudo foi caracterizar a qualidade nutricional da silagem de forrajem de quinoa (Chenopodium quinoa willd) variedade amarela de maranganí com adição de microorganismos eficientes na relação com a idade da quinoa e os diferentes períodos de fermentação da silagem. Recoletou-se o material vegetal (folhas e talos) de quinoa, avaliaram-se três idades de corte: 60, 90 e 120 dias e quatro períodos de fermentação da silagem: sete, quatorze, vinte e um e trinta dias. Realizaram-se 4 tratamentos: tratamento 1 (T1) se refere ao control sem aplicar nenhum tipo de EM, aos tratamentos T2, T3 Y T4 se aplicou EM nas dosagens indicadas na etiqueta como aditivo para silagens, cada tratamento se realizou por triplicado. O material vegetal se desidratou durante um período de 5 horas e posteriormente se elaboraram os microsilos de follaje de quinua. Se determinó el valor nutritivo (materia seca, fibra em detergente neutra, fibra em detergente acida, cenizas y proteína cruda) al follaje y a los microsilos de quina. Se utilizou um desenho completamente aleatório (DCA) com uma organização de parcelas divididas no tempo, se fez uma análise de variação utilizando o Modelo Linear Misto e uma separação de médias pelo método de Duncan e uma correlação de variáveis de Pearson. Para a variável humidade se encontrou um intervalo de 81,3 - 87,7% para el T1 e um intervalo de valores de 57,3 - 90,3% para os demais tratamentos. As cinzas se mantiveram em valores similares à folhagem de quinoa em relação às diferentes idades de rebrote, a maior porcentagem de cinzas se obteve aos 21 dias de fermentação da silagem com um valor de 20,3% para T3 com a silagem de folhagem de quinoa de 90 dias de rebrote; entanto que o conteúdo de proteína crua diminuiu ligeiramente em relação ao T1 na idade de rebrote dos 120 dias apresentando variações significativas entre os tratamentos com valores de 11,3-17,3%. Se apresentou uma relação positiva perfeita diretamente proporcional (P≤0,01) entre as médias de FDA e FDN (r=0,975) para todos os tratamentos avaliados. A planta de quinoa permitiria um uso multipropósito do cultivo, gerando grão para o consumo humano e folhagem para o consumo animal.

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This work explores the effect of two metallic wastes (mining wastes, MW; fly ashes, FA) and micro-aeration (MA) on the anaerobic digestion of wastewater which is rich in sulfate and sulfide. Two initial COD concentrations (5,000 and 10,000 mg/L) were studied under both conditions in batch systems at 35 °C, with a fixed COD/SO42- ratio = 10, with 100 mg/L of S2-. It was observed that the use of MW and FA in the assays with an initial COD concentration of 10,000 mg/L resulted in a simultaneous increase in COD removal, sulfate removal, sulfide removal and methane generation, while MA only improved the COD and sulfide removals in comparison with the control system. On the contrary, the use of MW, FA or MA in systems with initial COD concentrations equal to or lower than 5,000 mg/L did not show any improvement with respect to the control system in terms of COD removal, sulfate removal or methane generation, with only sulfide removal being positively affected by MW and FA.

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OBJECTIVES: Analyze the role of two members of the United States Congress, two private enterprises, and the government of Puerto Rico in the approval of the counterproductive law "Ban on the Deposit and Disposal of Coal Ash or Coal Combustion Residuals in Puerto Rico" (Law No. 40) in the framework of the four principles for environmental policy making. METHODS: The gathered text documents were structured, reviewed, and coded using a content analysis protocol to produce coding categories and the final analysis. RESULTS: Two US congressmen, apparently influenced by private enterprises, had a decisive role in the approval of Law No. 40 which failed to comply with any of the four principles for environmental public policy making. CONCLUSIONS: Puerto Rico's Government succumbed to the extortion strategy of two US congressmen and private economic interests, and finally approved Law No. 40 which mistreats the general public and the environmental health of two low socioeconomic status communities in the municipalities of Guayama and Peñuelas. This law has the potential to negatively affect public health and the environment island-wide.

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This study investigated the reactivity properties of self-leveling hybrid alkali-activated cements, such as ordinary Portland cement (OPC) and its residual precursors, coal bottom ash (BA), and rice husk ash (RHA). Due to the relatively low reactivity of BA, binary mixes were produced with OPC using contents of 2.5⁻30% in the treated BA samples. Furthermore, ternary mixes were prepared in proportions of 25%, 50%, and 75% with RHA as a replacement material for the OPC (mix with 90%:10% BA:OPC). For all of the mixes the spreading behaviors were fixed to obtain a self-levelling mortar, and dimensional changes, such as curling and shrinkage, were performed. Mortars with 30% OPC reached a compressive strength of 33.5 MPa and flexural strength of 7.53 MPa. A scanning electron microscope (SEM) and X-ray powder diffraction (XRD) were used to indicate the formation of N-A-S-H and a (N,C)-A-S-H gel, similar to the gel with trace of calcium. The best performance was achieved when the binary mix produced 10% OPC. A hybrid mortar of OPS-BA presented 10 times lower susceptibility to curling than an OPC mortar. The results showed that both ashes reduced the shrinkage and curling phenomena.

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Introducción: La frecuencia de las enfermedades respiratorias en general y en particular la de las crónico degenerativas ha incrementado notablemente en los últimos años en nuestro país. La ceniza volcanica podría estar relacionada con este incremento, haciéndonos más susceptibles a padecerlas. El objetivo del presente estudio fue determinar la frecuencia de las patologías respiratorias en la población más expuesta a los efectos de la ceniza y demás gases emanados por el volcán Tungurahua. Metodología: En el presente se incluyeron 100 personas residentes en las comunidades más afectadas por la ceniza del volcán Tungurahua (Penipe, Puela, Manzano, Bayushig, El Altar), quienes fueron sometidos a una evaluación clínica, radiológica y espirométrica. Resultados: 37 (37 %) de las personas estudiadas fueron de género masculino y 63 (63 %) femenino. 50 pacientes es decir el 50 % fue sintomático respiratorio. El 64 % de pacientes presentó cambios radiológicos sugerentes de cambios bronquíticos. En la espirometría el 23 % de pacientes presentó un patrón restrictivo de leve a moderado. Conclusiones: La población expuesta a la ceniza del volcán Tungurahua mostró cambios radiográficos, clínicos y espirométricos indicativos de enfermedades respiratorias que posiblemente se deben a la exposición a la ceniza volcánica.

Introduction: Frequency of respiratory diseases in general and in particular chronic degenerative diseases have notably increased in recent years in our country. Volcanic ashes could play a role in this incrementent, making us more suscpetible to suffer them. The objective of the present study was to determine frequency of respiratory pathologies in the population most exposed to the effects of ash and other gases emanated from the Tungurahua volcano. Methodology: In the present study there were included 100 people who were residents of the comunities most affected by the ashes of the Tungurahua volcano (Penipe, Puela, Manzano, Bayushig, El Altar). People were subjected to clinical, radiological and spirometric evaluation. Results: 37 (37%) of the studied population were men and 63 (63%) were women. 50 patients (50%) reported respiratory symptoms. 64% of patients showed radiological changes which suggested bronchitic changes. Spirometric evaluation showed a mild to moderate restrictive pattern in 23% of patients. Conclusions: Population exposed to ash of the Tunguraua volcano showed clinic, radiographic and spirometric changes that suggest respiratory diseases which possibly are due to exposition to volcanic ashes.

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Wildfire is very common in Brazilian savannas, and its effects on water, soil and aquatic/soil organisms are poorly understood. In this study, we observed the effects of fire, especially of ashes, on surface soil and subsurface water in a typical Brazilian savanna (Cerrado sensu strictu) for one year. Soil analyses (pH, organic matter content, potential acidity, K, Ca, Mg and P) and subsurface water analyses (NO3-, PO43- Mg2+, Ca2+ and K+) were assessed. We evaluated the ecotoxicological effects of ashes on three different endpoints and species, in fish Danio rerio (embryonic development), aquatic snail Biomphalaria glabrata (reproduction) and a soil species Enchytraeus sp. (reproduction). We found a higher amount of exchangeable cations and organic matter content in short-term fire effects on soil, but the higher availability of nutrients did not affect the soil pH in field plots. The effects of ashes on soil and subsurface water did not persist for one-year post-fire, except for organic matter content in burned areas. No toxic effects were observed on hatching success and incidences of developmental abnormalities in D. rerio embryos. However, ash input had adverse effects on reproduction in snails and enchytraeids. We reported a statistically significant decrease in snail eggs exposed to the 50g.L-1 and 100g.L-1 of ashes after four weeks (p<0.05, Dunnett's test and Tukey test). Enchytraeus sp. reproduction was negatively influenced by the natural soil, which presents high acidity, and also when exposed directly to the ashes from burned area, suggesting that pH and other ash compounds may limit the growth of enchytraeids. More studies in burned areas are strongly encouraged, addressing the potential important routes of exposure to ashes in order to understand the impact of intense fires on soil and aquatic biota in tropical savannas.

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Los hongos micorrícicos arbusculares (HMA) incrementan la toma de fosfatos solubles, mientras que los hongos solubilizadores de fósforo (S) promueven la solubilización de complejos insolubles de fosfato, en conjunto benefician la nutrición de las plantas. La utilización de estos organismos en combinación con minerales o rocas que aportan nutrientes es otra alternativa para mantener la productividad de los cultivos. El objetivo de este trabajo fue combinar HMA y S con materiales piroclásticos (cenizas y pumicitas) del volcán Puyehue y rocas fosfóricas (RP) del Grupo Río Chico (Chubut) y evaluar el desempeno de estas mezclas como sustratos para la producción en maceta de Lactuca sativa. Para formular los sustratos, se utilizó como base una mezcla de Terrafertil® con cenizas. Penicillium thomii fue el S y esporas del hongo Rhizophagus intraradices (AEGIS® Irriga) sirvieron de fuente del HMA. Se evaluaron diversas combinaciones de microorganismos y la adición o no de RP. Los tratamientos fueron: 1) sustrato; 2) sustrato + HMA; 3) sustrato + S; 4) sustrato + HMA + S; 5) sustrato: RP; 6) sustrato: RP + HMA; 7) sustrato: RP + S, y 8) sustrato: RP+ HMA + S. Se efectuaron 3 repeticiones por tratamiento. Los parámetros evaluados fueron el contenido de P total y asimilable en el sustrato, el P en el tejido vegetal y la biomasa seca. Todos ellos fueron significativamente mayores en las plantas que crecieron en el sustrato adicionado con RP e inoculadas con S y HMA. Este trabajo confirma que la combinación S/HMA con cenizas volcánicas del Puyehue y las RP del Grupo Río Chico formuladas con un sustrato comercial promueven el crecimiento de L. sativa. De este modo es posible incrementar el valor agregado de geomateriales de origen nacional.

Arbuscular mycorrhizal fungi (AMF) increase the uptake of soluble phosphates, while phosphorus solubilizing fungi (S) promote solubilization of insoluble phosphates complexes, favoring plant nutrition. Another alternative to maintaining crop productivity is to combine minerals and rocks that provide nutrients and other desirable properties. The aim of this work was to combine AMF and S with pyroclastic materials (ashes and pumices) from Puyehue volcano and phosphate rocks (PR) from Rio Chico Group (Chubut) - to formulate a substrate for the production of potted Lactuca sativa. A mixture of Terrafertil®:ashes was used as substrate. Penicillium thomii was the solubilizing fungus and Rhizophagus intraradices spores (AMF) was the P mobilizer (AEGIS® Irriga). The treatments were: 1) Substrate; 2) Substrate + AMF; 3) Substrate+S; 4) Substrate + AMF+ S; 5) Substrate: PR; 6) Substrate: PR + AMF; 7) Substrate: PR + S and 8) Substrate: PR + AMF + S. Three replicates were performed per treatment. All parameters evaluated (total and assimilable P content in substrate, P in plant tissue and plant dry biomass) were significantly higher in plants grown in substrate containing PR and inoculas with S and AMF. This work confirms that the combination of S/AMF with Puyehue volcanic ashes, PR from the Río Chico Group and a commercial substrate promote the growth of L. sativa, thus increasing the added value of national geomaterials.

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Arbuscular mycorrhizal fungi (AMF) increase the uptake of soluble phosphates, while phosphorus solubilizing fungi (S) promote solubilization of insoluble phosphates complexes, favoring plant nutrition. Another alternative to maintaining crop productivity is to combine minerals and rocks that provide nutrients and other desirable properties. The aim of this work was to combine AMF and S with pyroclastic materials (ashes and pumices) from Puyehue volcano and phosphate rocks (PR) from Rio Chico Group (Chubut) - to formulate a substrate for the production of potted Lactuca sativa. A mixture of Terrafertil®:ashes was used as substrate. Penicillium thomii was the solubilizing fungus and Rhizophagus intraradices spores (AMF) was the P mobilizer (AEGIS® Irriga). The treatments were: 1) Substrate; 2) Substrate+AMF; 3) Substrate+S; 4) Substrate+AMF+S; 5) Substrate: PR; 6) Substrate: PR+AMF; 7) Substrate: PR+S and 8) Substrate: PR+AMF+S. Three replicates were performed per treatment. All parameters evaluated (total and assimilable P content in substrate, P in plant tissue and plant dry biomass) were significantly higher in plants grown in substrate containing PR and inoculas with S and AMF. This work confirms that the combination of S/AMF with Puyehue volcanic ashes, PR from the Río Chico Group and a commercial substrate promote the growth of L. sativa, thus increasing the added value of national geomaterials.

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In a global scenario of climate change, several studies have predicted an increase in fires in different parts of the world. With the occurrence of rains following the fires in the Brazilian savanna (Cerrado biome), the compounds present in ashes may enter aquatic environments and cause adverse effects to these ecosystems. In this context, this study evaluated the potential toxicity of ashes from two areas of Cerrado and an area of pasture, through ecotoxicological bioassays and using three aquatic species from distinct trophic levels, which were exposed to different dilutions of ashes: the microcrustacean Ceriodaphnia dubia, the fish Danio rerio and the mollusc Biomphalaria glabrata. The ashes from the three sampled areas showed higher concentrations of some elements in relation to the soil samples (B, Ca, K, Mg, Mn, P, S, Si, Sr, Zn), but only a small quantity of these compounds was solubilised. Our data showed that all ash samples caused acute toxicity to C. dubia (48hs-LC50 = 13.4 g L-1; 48hs-LC50 = 6.33 g L-1; 48hs-LC50 = 9.73 g L-1 respectively for transition area, pasture, typical cerrado areas), while in relation to D. rerio and B. glabrata, no acute toxicity was observed when they were exposed to ashes from native Cerrado vegetation and pasture areas. Ashes from a transition area showed toxicity for D. rerio (48hs-LC50 = 25.0 g L-1); possibly, this was due to the combination of multiple preponderant inorganic elements of ashes with other organic compounds not analysed, such as polycyclic aromatic hydrocarbons (PAHs). In summary, these results suggest that wildfires may pose risks to zooplankton communities and emphasize the need for more studies to better understand the complexity of the ecological effects of fire on aquatic ecosystems.

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There are multiple elements which enable coal geochemistry: (1) boiler and pollution control system design parameters, (2) temperature of flue gas at collection point, (3) feed coal and also other fuels like petroleum coke, tires and biomass geochemistry and (4) fuel feed particle size distribution homogeneity distribution, maintenance of pulverisers, etc. Even though there is a large number of hazardous element pollutants in the coal-processing industry, investigations on micrometer and nanometer-sized particles including their aqueous colloids formation reactions and their behaviour entering the environment are relatively few in numbers. X-ray diffraction (XRD), High Resolution-Transmission Electron microscopy (HR-TEM)/ (Energy Dispersive Spectroscopy) EDS/ (selected-area diffraction pattern) SAED, Field Emission-Scanning Electron Microscopy (FE-SEM)/EDS and granulometric distribution analysis were used as an integrated characterization techniques tool box to determine both geochemistry and nanomineralogy for coal fly ashes (CFAs) from Brazil´s largest coal power plant. Ultrafine/nano-particles size distribution from coal combustion emissions was estimated during the tests. In addition the iron and silicon content was determined as 54.6% of the total 390 different particles observed by electron bean, results aimed that these two particles represent major minerals in the environment particles normally. These data may help in future investigations to asses human health actions related with nano-particles.

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Exposure to coal and coal ashes can cause harmful effects in in vitro and in vivo systems, mainly by the induction of oxidative damage. The aim of this work was to assess cytotoxic and genotoxic effects using the V79 cell line treated with coal and coal fly ash particles derived from a coal power plant located in Santa Catarina, Brazil. Two coal samples (COAL11 and COAL16) and two coal fly ash samples (CFA11 and CFA16) were included in this study. COAL16 was co-firing with a mixture of fuel oil and diesel oil. The comet assay data showed that exposure of V79 cells to coal and coal fly ash particles induced primary DNA lesions. Application of lesion-specific endonucleases (FPG and ENDO III) demonstrated increased DNA effects indicating the presence of high amounts of oxidative DNA lesions. The cytokinesis-block micronucleus cytome assay analysis showed that exposure of V79 cells to high concentrations of coal and coal fly ash particles induced cytotoxic effects (apoptosis and necrosis) and chromosomal instability (nucleoplasmic bridges, nuclear buds, and micronucleus (MN) formation). These results may be associated with compounds contained in the surface of the particles as hazardous elements, ultrafine/nanoparticles, and polycyclic aromatic hydrocarbons (PAHs) which were detected in the samples. Graphical abstract ᅟ.

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Events such as volcanic eruptions may act as disturbance agents modifying the landscape spatial diversity and increasing environmental instability. On June 4, 2011 the Puyehue-Cordon Caulle volcanic complex located on Chile (2236 m.a.s.l., 40° 02' 24" S- 70° 14' 26" W) experience a rift zone eruption ejecting during the first day 950 million metric tons into the atmosphere. Due to the westerly winds predominance, ash fell differentially upon 24 million ha of Patagonia Argentinean, been thicker deposits accumulated towards the West. In order to analyze changes on stream fish assemblages we studied seven streams 8, 19 and 30 months after the eruption along the ash deposition gradient, and compare those data to pre eruption ones. Habitat features and structure of the benthic macroinvertebrate food base of fish was studied. After the eruption, substantial environmental changes were observed in association with the large amount of ash fallout. In western sites, habitat loss due to ash accumulation, changes in the riparian zone and morphology of the main channels were observed. Turbidity was the water quality variable which reflected the most changes throughout time, with NTU values decreasing sharply from West to East sites. In west sites, increased Chironomid densities were recorded 8 months after the initial eruption as well as low EPT index values. These relationships were reversed in the less affected streams farther away from the volcano. Fish assemblages were greatly influenced both by habitat and macroinvertebrate changes. The eruption brought about an initial sharp decline in fish densities and the almost total loss of young of the year in the most western streams affecting recruitment. This effect diminished rapidly with distance from the emission center. Thirty months after the eruption, environmental changes are still occurring as a consequence of basin wide ash remobilization and transport.

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ABSTRACT The aim of this study was to analyze the influence of solid waste on the cultivation of the microalgae Spirulina sp. LEB 18 and Chlorella fusca LEB 111 with 0, 40, 80 and 120 ppm of mineral coal ash. The addition of the ash did not inhibit the cultivation of microalgae at the tested concentrations, showing that it could be used for the cultivation of these microalgae due to the minerals present in the ash, which might substitute the nutrients needed for their growth.