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1.
Environ Sci Technol ; 58(16): 7124-7132, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38599582

RESUMO

Often large quantities of plastics are found in compost, with price look-up stickers being a major but little-explored component in the contamination path. Stickers glued to fruit or vegetable peels usually remain attached to the organic material despite sorting processes in the composting plant. Here, we investigated the effects of industrial composting on the structural alterations of these stickers. Commercial polypropylene (PP) stickers on banana peels were added to a typical organic material mixture for processing in an industrial composting plant and successfully resampled after a prerotting (11 days) and main rotting step (25 days). Afterward, both composted and original stickers were analyzed for surface and structural changes via scanning electron microscopy, Fourier-transform infrared spectroscopy, and micro- and nano-X-ray computed tomography (CT) combined with deep learning approaches. The composting resulted in substantial surface changes and degradation in the form of microbial colonization, deformation, and occurrence of cracks in all stickers. Their pore volumes increased from 16.7% in the original sticker to 26.3% at the end of the compost process. In a similar way, the carbonyl index of the stickers increased. Micro-CT images additionally revealed structural changes in the form of large adhesions that penetrated the surface of the sticker. These changes were accompanied by delamination after 25 days of composting, thus overall hinting at the degradation of the stickers and the subsequent formation of smaller microplastic pieces.


Assuntos
Compostagem , Frutas , Plásticos , Tomografia Computadorizada por Raios X , Solo/química , Microscopia Eletrônica de Varredura , Polipropilenos/química
2.
Small ; 18(42): e2202987, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36073667

RESUMO

Liquid metals (LMs) play a growing role in flexible electronics and connected applications. Here, LMs come into direct contact with metal electrodes thus allowing for corrosion and additional alloying, potentially compromising device stability. Nevertheless, comprehensive studies on the interfacial interaction of the materials are still sparse. Therefore, a correlated material interaction study of capillary-printed Galinstan (eutetic alloy of Ga/In/Sn) with gold surfaces and electrodes is conducted. Comprehensive application of optical microscopy, vertical scanning interferometry, scanning electron microscopy/spectroscopy, x-ray photon spectroscopy, and atomic force microscopy allow for an in depth characterization of the spreading process of LM lines on gold films, revealing the differential spread of the different LM components and the formation of intermetallic nanostructures on the surface of the surrounding gold film. A model for the growth process based on the penetration of LM along the gold film grain boundaries is proposed based on the obtained time-dependent characterization. The distribution of gold, Galinstan, and intermetallic phases in a gold wire dipped into LM is observed using X-ray nano tomography as a complementary view on the internal nanostructure. Finally, resistance measurements on LM lines connecting gold electrodes over time allow to estimate the influence on the material interaction on electronic applications.

3.
J Sci Food Agric ; 99(10): 4642-4650, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30895630

RESUMO

BACKGROUND: The elemental profile of the Marselan wine cycle was studied with a single ion-beam technique, namely particle-induced X-ray emission (PIXE). Samples were collected from all of the major stages involved in the wine cycle, including soil, vine plant, grape, and different stages of wine processing. RESULTS: The results show the influence of field practices on the elemental composition of leaves, branches, grapes, and soil. Mechanisms of element precipitation and elimination from the wine were identified through the changes in the elemental concentrations measured during the post-harvesting processes. The concentrations of some elements, such as Al, Si, K, and Ni, did not vary for grapes collected at different maturation stages. On the other hand, changes in the concentrations of Si, Cl, Ca, Cu, and K were observed right after the maceration and pressing processes in young wine. Finally, the reduction in the Cu concentration during the last stages of the wine cycle is related to its precipitation in the storage tanks. CONCLUSIONS: It was found that field practices and winemaking processes played distinct roles in the elemental composition of grapes and wine from different preparation stages. Moreover, PIXE proved to be a suitable analytical tool for the analysis of the whole wine cycle because it handles solid and liquid samples in a clean and straightforward manner. © 2019 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Oligoelementos/análise , Vitis/química , Vinho/análise , Frutas/química , Solo/química
5.
Ecotoxicol Environ Saf ; 107: 133-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24927390

RESUMO

During coal mining activities, large quantities of coal dust, ashes, polycyclic aromatic hydrocarbons and metals are released into the environment. This complex mixture presents one of the most important occupational hazards for health of workers. The aim of the present study was to evaluate the genetic damage together with the presence of inorganic elements, in an exposed workers population to coal mining residues of Guajira-Colombia. Thus, 100 exposed workers and 100 non-exposed control individuals were included in this study. To determine genetic damage we assessed the micronucleus (MN) frequencies and nuclear buds in buccal mucosa samples (BMCyt) assay, which were significantly higher in the exposed group than non-exposed control group. In addition, karyorrhectic and karyolytic cells were also significantly higher in the exposed group (cell death). No significant difference was observed between the exposed groups engaged in different mining activities. No correlation between age, alcohol consumption, time of service and MN assay data were found in this study. However, the content of inorganic elements in blood samples analyzed by a Particle-induced X-ray emission technique (PIXE) showed higher values of silicon (Si) and aluminum (Al) in the exposed group. In this study we discuss the possibility of DNA damage observed in the mine workers cells be a consequence of oxidative damage.


Assuntos
Minas de Carvão , Dano ao DNA , Mucosa Bucal/citologia , Exposição Ocupacional/análise , Adulto , Análise Química do Sangue , Estudos de Casos e Controles , Morte Celular , Carvão Mineral/efeitos adversos , Poeira , Humanos , Masculino , Testes para Micronúcleos/métodos , Pessoa de Meia-Idade , Mucosa Bucal/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Espectrometria por Raios X , Adulto Jovem
6.
Arch Environ Contam Toxicol ; 66(1): 69-77, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23974155

RESUMO

It has been identified worldwide that amphibians are experiencing massive population declines. This decrease could be further enhanced by the exposure of amphibians to pollutants, which would enhance reactive oxygen species production and cause subsequent alterations in oxidant defense levels. The present study was aimed at understanding the impact of mineral coal on amphibians. For this purpose, chemical elemental contents and oxidative stress indexes in Hypsiboas faber from coal-mining areas and in an unpolluted area in the Catarinense Coal Basin, Brazil, were assessed. The highest contents of sulfur, chlorine, iron, zinc, and bromine were registered in specimens from the coal-mining area, whereas the highest contents of potassium calcium, and silicon were registered in specimens from the control area. It was found that there was a significant increase (p < 0.05) in the activity of super oxide dismutase (SOD) and glutathione peroxidase (GPx) in the animals from the coal-mining area, whereas the level of catalase showed no differences between the animal groups. The levels of TBARS showed no differences between the tested groups. However, carbonylation decreased significantly (p < 0.05) in animals from the coal-mining area, and there was a significant increase (p < 0.05) in the formation of total thiols in animals from the coal-mining area. In conclusion, the antioxidant system of H. faber is sensitive to pollutants present in coal-mining wastes, and its SOD and GPx activity may be a potential biomarker for monitoring the level of contaminants in the environment.


Assuntos
Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Anuros/metabolismo , Biomarcadores/metabolismo , Brasil , Catalase/metabolismo , Minas de Carvão , Glutationa Peroxidase/metabolismo , Metais Pesados/toxicidade , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Poluentes Químicos da Água/toxicidade
7.
Arch Environ Contam Toxicol ; 65(3): 434-41, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23733085

RESUMO

During coal combustion, hazardous elements are discharged that impair environmental quality. Plant cover is the first available surface for the atmospheric pollutants in terrestrial ecosystems. The aim of this study was to evaluate genotoxicity in the aqueous extract of the native plant, Baccharis trimera, exposed to coal and emissions from a thermal power plant (coal-fired power plant in Candiota, Brazil), correlating seasonality, wind tunnel predominance, and presence of inorganic elements. The presence of inorganic elements in the aerial parts of B. trimera was analyzed by particle-induced X-ray emission (PIXE) spectrometry, and genotoxicity was evaluated by ex vivo comet assay. The genotoxic effects of aqueous extracts of B. trimera from four sites located in the area around power plant were analyzed by comet assay in peripheral human lymphocytes. Winter samples showed greater levels of metals than summer samples. Genotoxicity was detected in B. trimera extracts collected from the region exposed to extraction and burning coal. Extracts from the site impacted by the dominant wind induced more damage to DNA than those from other sites. Based on our data, we can suggest that in winter the inorganic elements from extraction and burning of coal and carried through the wind tunnel were responsible for the genotoxicity observed in aqueous extract of B. trimera.


Assuntos
Poluentes Atmosféricos/toxicidade , Baccharis/efeitos dos fármacos , Carvão Mineral/toxicidade , Monitoramento Ambiental/métodos , Metais/toxicidade , Movimentos do Ar , Poluentes Atmosféricos/análise , Baccharis/genética , Brasil , Carvão Mineral/análise , Ensaio Cometa , Dano ao DNA , Humanos , Linfócitos/efeitos dos fármacos , Masculino , Metais/análise , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/efeitos dos fármacos , Centrais Elétricas , Estações do Ano , Espectrometria por Raios X
8.
Curr Res Food Sci ; 4: 670-678, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34632409

RESUMO

The variations of the elemental concentrations in sparkling white wine and respective cork stoppers throughout 18 months of storage time were determined with the PIXE (Particle-Induced X-ray Emission) technique. Three portions of the cork stoppers were analyzed: the top part (external layer), the inner part (bulk layer) and the bottom layer (which was in contact with the sparkling wine). Elements such as Na, Mg, Si, P, S, Cl, K, Ca, Mn, Fe, Zn and Rb were determined for both cork stoppers and sparkling wine samples. Similar concentrations of Si, P, S, Cl and Ca were found in the external and bottom layers of the corks. Distinct behaviors of the changes in the elemental concentrations as a function of the time were observed for cork stoppers and sparkling wines. The concentrations of Mg, S, K, Ca, Cu, Sr and Ba increased in the bottom layer of the cork as a function of storage time. On the other hand, concentrations of Al, Si, Cl, Ti, Zn and Br proved to be invariant, while the concentrations of P and Fe showed a slight decrease. Concerning the sparkling wine, an increasing trend of elemental concentrations was observed for most elements throughout the storage time. A diffusion mechanism of elements in the cork and the role of the secondary fermentation in the bottle are discussed.

9.
Food Res Int ; 119: 297-304, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884660

RESUMO

Brazilian coffee is well known worldwide due to its quality and richness in taste. The aim of the present study is to provide the elemental characterization of Brazilian coffee along different stages of the drip brewing process. To that end, samples from roasted ground coffee, spent coffee, paper filters and the final beverage were analyzed with one single ion beam technique, namely particle-induced X-ray emission (PIXE). In total, over 140 samples from 8 different Brazilian brands of ground coffee were analyzed. Large differences in some elemental concentrations were observed among different brands and among different batches of a single brand, which leads to high variances in the data. Concerning the beverage preparation, the analysis of the spent coffee shows that the transfer ratio from the ground coffee to the beverage differs for each element. Our results indicate that potassium and chlorine have the highest transfer ratio. Moreover, the concentration of rubidium is relatively high in drinking coffee. Finally, there is no influence of the elemental composition of paper filter in the preparation of drinking coffee.


Assuntos
Café/anatomia & histologia , Tecnologia de Alimentos/métodos , Extratos Vegetais/química , Bebidas , Brasil , Filtração , Temperatura Alta , Espectrometria por Raios X , Paladar
10.
Rev Soc Bras Med Trop ; 47(4): 517-20, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25229296

RESUMO

INTRODUCTION: The treatment of leishmaniasis ischallenging, given the difficulties in drug administration and resistance. Therefore, we chose to test the efficacy of miltefosine combined with pentoxifylline. METHODS: Twenty-seven isogenic C57Bl/6 mice were infected with Leishmania (Leishmania) amazonensis, and equally divided into three groups: miltefosine (200mg/kg/day), miltefosine (200mg/kg/day) with pentoxifylline (8mg/kg/day), and untreated. Response to treatment was evaluated using paw diameter and parasitological criteria. RESULTS: The number of viable Leishmania reduced significantly within the miltefosine-pentoxifylline group (p < 0.05). CONCLUSIONS: There is hope that a viable treatment exists for Leishmania infection.


Assuntos
Antiprotozoários/administração & dosagem , Leishmaniose Cutânea/tratamento farmacológico , Pentoxifilina/administração & dosagem , Fosforilcolina/análogos & derivados , Administração Oral , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Camundongos Endogâmicos C57BL , Fosforilcolina/administração & dosagem , Fatores de Tempo
11.
Environ Toxicol Pharmacol ; 36(1): 194-201, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23619523

RESUMO

The aims of the study were to determine the heavy metal content in the tissues of Hypsiboas faber from a coal mining area and to compare the DNA damage in the blood cells of these animals with that of animals living in an unpolluted area. The heavy metal content was detected according to the technique of Particle-Induced X-ray Emission (PIXE) and the DNA damage was assessed by the Comet assay. Our results reveal that the specimens of H. faber collected from the coal mining area exhibited elements of order Fe>Cu>Al>Zn>Rb>Mn>Br, independently of the organ. The values of Comet assay parameters (DNA damage index and DNA damage frequency) were significantly higher in specimens collected from the coal mining area than in the reference animals. Our study concludes that the coal mining residues are genotoxic to amphibians and may have adverse effects on soil, water, vegetation and wild animals.


Assuntos
Anuros/metabolismo , Minas de Carvão , Dano ao DNA , Poluentes Ambientais/análise , Metais/análise , Animais , Brasil , Bromo/análise , Bromo/toxicidade , Ensaio Cometa , Monitoramento Ambiental , Poluentes Ambientais/toxicidade , Rim/química , Fígado/química , Masculino , Metais/toxicidade , Músculo Esquelético/química
12.
Environ Mol Mutagen ; 54(1): 65-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23055270

RESUMO

Coal is the largest fossil fuel source used for the generation of energy. However, coal extraction and its use constitute important pollution factors; thus, risk characterization and estimation are extremely important for the safety of coal workers and the environment. Candiota is located to the southeast of the state of Rio Grande do Sul and has the largest coal reserves in Brazil, and the largest thermal power complex in the state. In the open-cast mines, the coal miners are constantly exposed to coal dust. The human buccal micronucleus cytome (BMCyt) assay has been used widely to investigate biomarkers for DNA damage, cell death, and basal cell frequency in buccal cells. The aim of this study was to assess whether prolonged exposure to coal dust could lead to an increase in genomic instability, cell death, and frequency of basal cells using the BMCyt assay. In the analysis of epithelial cells, the exposed group (n = 41) presented with a significantly higher frequency of basal cells, micronuclei in basal and differentiated cells, and binucleated cells compared to the non-exposed group (n = 29). The exposed group showed a significantly lower frequency of condensed chromatin cells than the non-exposed group. However, we found no correlation between DNA damage and metal concentration in the blood of mine workers. DNA damage observed in the mine workers may be a consequence of oxidative damage resulting from exposure to coal residue mixtures. In addition, our findings confirm that the BMCyt assay can be used to identify occupational risk.


Assuntos
Minas de Carvão , Dano ao DNA , Testes para Micronúcleos/métodos , Mucosa Bucal/citologia , Exposição Ocupacional/análise , Adulto , Brasil , Morte Celular , Poeira , Instabilidade Genômica , Humanos , Masculino , Metais/sangue , Pessoa de Meia-Idade , Solo/análise , Fatores de Tempo
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