Identification of hazardous nanoparticles present in the Caribbean Sea for the allocation of future preservation projects

The deposition of remaining nanoparticles in the Caribbean Sea generates the formation of potentially dangerous elements, which influence at the imbalance of ecosystems. The detection of nanoparticles is not simple and the use of conventional methods is difficult application, which is why we highlight the immediacy and importance of this research for the areas of marine biology, urbanism, engineering and geosciences, applied in the Caribbean Sea. The general objective of this study is to evaluate the use of advanced methods for the determination of toxic nanoparticles, which can directly affect the development of marine organisms in the aquatic ecosystem in waters of the Caribbean Sea, favoring the construction of future international public policies with the elaboration of projects capable of mitigating these levels of contamination. The morphology and structure of nanoparticles were analyzed by emission scanning electron microscope with a high-resolution electron microscope. The nanoparticles smaller than 97 nm were identified in different proportions. The morphological analyses indicated nanoparticles' presence in the form of nanotubes, nanospheres, and nanofibers, which were shown in an agglomerated form. The presence of potentially hazardous elements, such as As, Cd, Pb, Mg, Ni and V were verified. In addition, the presence of asbestos in the form of minerals was confirmed, and that of titanium dioxide was found in large quantities. The results provide new data and emphasize the possible consequences to the in the Caribbean Sea, with the identification of dangerous elements (As, Cb, Pb, Hg, Ni and V), harmful to the marine ecosystem. Therefore, there is a need for strict control to reduce contamination of the Caribbean Sea and avoid risks to the ecosystem and public health, through suggestions of international public policies, through constant monitoring and the application of environmental recovery projects in this marine estuary

Identification of hazardous nanoparticles present in the Caribbean Sea for the allocation of future preservation projects

The deposition of remaining nanoparticles in the Caribbean Sea generates the formation of potentially dangerous elements, which influence at the imbalance of ecosystems. The detection of nanoparticles is not simple and the use of conventional methods is difficult application, which is why we highlight the immediacy and importance of this research for the areas of marine biology, urbanism, engineering and geosciences, applied in the Caribbean Sea. The general objective of this study is to evaluate the use of advanced methods for the determination of toxic nanoparticles, which can directly affect the development of marine organisms in the aquatic ecosystem in waters of the Caribbean Sea, favoring the construction of future international public policies with the elaboration of projects capable of mitigating these levels of contamination. The morphology and structure of nanoparticles were analyzed by emission scanning electron microscope with a high-resolution electron microscope. The nanoparticles smaller than 97 nm were identified in different proportions. The morphological analyses indicated nanoparticles' presence in the form of nanotubes, nanospheres, and nanofibers, which were shown in an agglomerated form. The presence of potentially hazardous elements, such as As, Cd, Pb, Mg, Ni and V were verified. In addition, the presence of asbestos in the form of minerals was confirmed, and that of titanium dioxide was found in large quantities. The results provide new data and emphasize the possible consequences to the in the Caribbean Sea, with the identification of dangerous elements (As, Cb, Pb, Hg, Ni and V), harmful to the marine ecosystem. Therefore, there is a need for strict control to reduce contamination of the Caribbean Sea and avoid risks to the ecosystem and public health, through suggestions of international public policies, through constant monitoring and the application of environmental recovery projects in this marine estuary

Nanometric particles of high economic value in coal fire region: Opportunities for social improvement

Spontaneous coal combustion in the La Guajira coals was studied for the presence of carbon nanophases (e.g., carbon nanotubes), occurrence of rare earth elements (REEs) in them, and the probable mechanisms for concentration of these rare compounds. For this purpose, various techniques such as scanning electron microscopy (SEM), Field-emission SEM, transmission electron microscopy (TEM), high-resolution TEM, and focused ion beam (FIB) were used. The development and alteration of the nanoparticles by geo-processes during the early modification periods of coal combustion were explored. Certain types of carbon nanophases and REE compounds may constitute nanominerals and ultra-fine particles accumulated in the coal peat. Assemblages of these nanophases (crystalline and amorphous compounds), predominantly the clay-monazite relationship and its connection to tonsteins in the coal combustion zones in the east region of the coal mines studied in this work, indicate that the coal area was subjected to REE concentration. The carbon nanophases contained several potential hazardous elements (PHEs), including, arsenic, bromine, cadmium, chlorine, fluorine, mercury, and other PHEs. While carbon nanotubes have been known to be produced from spontaneous combustion of coal of varying ranks, the present work is the first report on the naturally occurring REEs and carbon nanophases in the Colombian coal mining area

Fire resistance performance of concrete-PVC panels with polyvinyl chloride (PVC) stay in place (SIP) formwork

Stay-in-place (SIP) formwork is a more-practical alternative to traditional steel or wood formworks due to its improved constructability and durability. The aim of this paper was to study the fire resistance performances of structural and non-structural concrete panels with polyvinyl chloride (PVC) SIP formwork. Three 124.01 in × 110.24 in × 3.15 in panels of PVC SIP formwork were tested and compared to one another. All panels were aged for 28 days, then exposed to the standard fire curve based on the ISO 834:2014 standard, and the temperatures in each panel surface recorded. The results indicate that concrete strength significantly influenced the structural stability and the fire resistance time of the panels (under load), even in this type of panels when exposed to high temperatures. It was found that the PVC encasement enhanced the thermal insulation property, one of the fire resistance performance criteria. Overall, the importance of this alternative formwork is the reduction in the use of forest resources, the raise of awareness of their conservation, and the promotion of their rational use as this a material is friendly to the environment

Formulation study of quercetin-loaded lipid-based nanocarriers obtained by hot solvent diffusion method

Lipid-based nanocarriers were prepared by hot solvent diffusion technique. Tristearin (TS) and/or castor oil were employed as oily phase, and Lutrol F68® or Solutol HS15® and lecithin were employed as surfactant and cosurfactant, respectively. The influence of the formulation variables on surface charge and size of the nanocarriers and their ability to load and control the release of quercetin were investigated. Solid lipid nanoparticles, nanostructured lipid carriers, nanoemulsions, and microemulsions (ME) were obtained depending on the formulation composition. Querecetin (QU) entrapment efficacy was higher than 99 % for all formulations. However, drug content was greatly affected by the formulation composition. ME exhibited the highest capacity to load QU, reaching a concentration around 1,300 times higher than its aqueous solubility. QU release profiles exhibited biphasic kinetics for all formulations. However, the release rate of QU was affected by the properties of the nanocarrier.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Portable dehumidifiers as an original matrix for the study of inhalable nanoparticles in school

Good air quality is documented as a significant factor of social justice. The human health hazards associated with air pollution are not distributed equally across cities; the most vulnerable people are more exposed to ambient air as they commute to work and wait for buses or trains at the stations. Aerosols play important roles in atmosphere quality and the climate; their oxidation at the nanoscale level may possibly increase the reactivity and toxicity of atmospheric particulates. Indoor school environments are characterized by high concentrations of different airborne particulate and gaseous pollutants. The documentation of nanoparticles (NPs), ultra-fine particles (UFPs), and micron-size particle species present in indoor primary schools are an important aspect in the recognition of their influence in respirational difficulties and decreased cognitive progress in children. This work utilizes the study of condensed water, sampled with portable dehumidifiers (PD), to describe NPs and UFPs in the vapor stage of enclosed zones. The acquired extracts were analyzed by advanced electron microscopy techniques. A total of 392 NPs and 251 UFPs were examined in a set of 22 samples acquired in moderately limited or inadequately ventilated indoor areas from several schools. Noting that NPs-related disorders happen at particular places of respirational structure, identification of site-specific NPs accumulation should be anticipated in direction to better verify the corresponding human health outcomes resulting from respirable NPs

Copper decreases associative learning and memory in Drosophila melanogaster

Copper is an essential element to all living organisms. Repeated use of metal-enriched chemicals, fertilizers, and organic substances may cause contamination at a large scale. Altered levels of Cu2+ may result in harmful effects and can be associated with memory and cognitive dysfunction. Studying simple, genetically tractable organisms such as Drosophila melanogaster, can reveal important data on the neural basis of conditioning. D. melanogaster is an important alternative experimental model to assess the toxic response to metals. In the present study, the effects of copper on flies’ development and in learning and memory retention in male and female adult flies were investigated. We paired an odorant to pain perception and observed the aversion behavior over time. Exposure of D. melanogaster eggs to Cu2+ increased mortality of larvae, pupae, and adults and decreased memory retention in adults. Moreover, male flies demonstrated to be more susceptible to Cu2+ toxicity than females. The results therefore, reinforce the importance of controlling the anthropogenic heavy-metals soil contamination given their hazardous effects to living organisms

Obese rats are more vulnerable to inflammation, genotoxicity and oxidative stress induced by coal dust inhalation than non-obese rats

Obesity is an important nutritional disorder worldwide. Its association with environmental pollution may trigger an increase in oxidative stress and inflammatory parameters. Coal is a resource used throughout the world as an important fuel source for generating electricity. The ashes released by the coal combustion cause serious problems for human health due to their high toxicity and their capacity to bioaccumulate. The aim of this work was to investigate the effects of coal dust inhalation in the organs of obese and non-obese Wistar rats. Pro-inflammatory cytokines, oxidative stress, oxidative damage, histological analysis, comet assay, and micronuclei were investigated. Both obesity and coal dust inhalation increased the pro-inflammatory cytokines IL-1β and TNF-α and decreased HSP70 levels in serum, however, in obese animals that inhaled coal dust these changes were more pronounced. Liver histological analysis showed severe microvesicular steatosis in obese animals that inhaled coal dust. Lung histologic investigation showed abnormalities in lung structure of animals exposed to coal dust and showed severe lung distensibility in obese animals exposed to coal dust

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In the last years many populations of anurans have declined and extinctions have been recorded. They were related to environmental pollution, changes of land use and emerging diseases. The main objective of this study was to determine copper sensitivity of the anuran of the Amazon Rhinella granulosa and Scinax ruber tadpoles at stage 25 and Scinax ruber eggs exposed for 96 h to copper concentrations ranging from 15 µg Cu L-1 to 94 µg Cu L-1. LC50 at 96 h of Rhinella granulosa Gosner 25, Scinax ruber Gosner 25 and Scinax ruber eggs in black water of the Amazon were 23.48, 36.37 and 50.02 µg Cu L-1, respectively. The Biotic Ligand Model was used to predict the LC50 values for these species and it can be considered a promising tool for these tropical species and water conditions. Copper toxicity depends on water physical-chemical composition and on the larval stage of the tadpoles. The Gosner stage 19-21 (related to the appearance of external gills) is the most vulnerable and the egg stage is the most resistant. In case of contamination by copper, the natural streams must have special attention, since copper is more bioavailable.Nos últimos anos foram registrados muitas extinções e declínios de populações de anuros. Eles estavam relacionados com a poluição do ambiente, a mudanças no uso da terra e ao surgimento de doenças. O principal objetivo deste estudo foi determinar a sensibilidade dos anuros amazônicos ao cobre. Os girinos de Scinax ruber e Rhinella granulosa no estadio 25 e os ovos de Scinax ruber foram expostos por 96 horas a concentrações de cobre entre 15 µg Cu L-1 a 94 µg Cu L-1. A CL50 -96 h dos girinos de Rhinella granulosa, dos girinos de Scinax ruber e dos ovos de Scinax ruber em águas pretas da Amazônia foram 23,48; 36,37 e 50,02 µg Cu L-1, respectivamente. O modelo do ligante biótico foi usado para prever os valores de CL50 para essas duas espécies e pode ser considerado uma ferramenta promissora para essas espécies tropicais e para essas condições de água. A Toxicidade de cobre depende da composição físico-química da água e do estagio larval dos girinos. O estadio 19-21 de Gosner (relacionados ao aparecimento das brânquias externas) são os mais vulnerável e o estagio de ovo é o mais resistente. Em caso de contaminação por cobre, os igarapés naturais devem ter uma atenção especial, uma vez que o cobre é mais biodisponível nesse ambiente