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1.
Environ Sci Pollut Res Int ; 31(3): 3526-3544, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38085483

RESUMO

The main objective of this study is to analyze hazardous elements in nanoparticles (NPs) (smaller than 100 nm) and ultrafine particles (smaller than 1 µm) in Porto Alegre City, southern Brazil using a self-made passive sampler and Sentinel-3B SYN satellite images in 32 collection points. The Aerosol Optical Thickness proportion (T550) identification was conducted using images of the Sentinel-3B SYN satellite at 634 points sampled in 2019, 2020, 2021, and 2022. Focused ion beam scanning electron microscopy analyses were performed to identify chemical elements present in NPs and ultrafine particles, followed by single-stage cascade impactor to be processed by high-resolution transmission electron microscopy. This process was coupled with energy-dispersive X-ray spectroscopy and later analysis via secondary ion mass spectrometry. Data was acquired from Sentinel-3B SYN images, normalized to a standard mean of 0.83 µg/mg, at moderate spatial resolution (260 m), and modeled in the Sentinel Application Platform (SNAP) software v.8.0. Statistical matrix data was generated in the JASP software (Jeffreys's Amazing Statistics Program) v.0.14.1.0 followed by a K-means cluster analysis. The results demonstrate the presence of between 1 and 100 nm particles of the following chemical elements: Si, Al, K, Mg, P, and Ti. Many people go through these areas daily and may inhale or absorb these elements that can harm human health. In the Sentinel-3B SYN satellite images, the sum of squares in cluster 6 is 168,265 and in cluster 7 a total of 21,583. The use of images from the Sentinel-3B SYN satellite to obtain T550 levels is of great importance as it reveals that atmospheric pollution can move through air currents contaminating large areas on a global scale.


Assuntos
Poluentes Atmosféricos , Nanopartículas , Humanos , Poluentes Atmosféricos/análise , Brasil , Monitoramento Ambiental/métodos , Material Particulado/análise , Aerossóis/análise , Tamanho da Partícula
2.
Environ Sci Pollut Res Int ; 30(32): 78139-78151, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37264169

RESUMO

In this work, different carbonaceous materials based on floated sludge from a poultry industry wastewater treatment plant (PI-WTP) were synthesized. These materials were characterized and investigated in methylene blue dye (MB) adsorption. The influences of the initial pH solution, adsorbent dosage, kinetics, equilibrium, and thermodynamics were evaluated in the adsorption experiments. A simulation of a real textile effluent was also carried out to evaluate the adsorbent. The results of the adsorbents' characterization demonstrated that adding ZnCl2 + lime, followed by pyrolysis and acid leaching, significantly improved the material's properties, leading to abundant porosity and high surface area. The adsorption experiments indicated that the natural pH of the solution (8.0) and the AC-II dosage of 0.75 g L-1 are optimal for MB removal. Elovich and Sips' models (with a maximum adsorption capacity of 221.02 mg g-1 at 328 K) best fitted the experimental kinetic and equilibrium data, respectively. The adsorption process is spontaneous and endothermic according to thermodynamic parameters. The discoloration efficiency of the simulated effluent was 67.8%. In conclusion, the floated sludge, a residue produced on a large scale that needs to be disposed of correctly, can be converted into a value-added material (carbonaceous adsorbent) and applied to treat colored effluents.


Assuntos
Esgotos , Poluentes Químicos da Água , Animais , Esgotos/química , Azul de Metileno/química , Aves Domésticas , Adsorção , Poluentes Químicos da Água/química , Termodinâmica , Cinética , Concentração de Íons de Hidrogênio
3.
Environ Sci Pollut Res Int ; 30(34): 82795-82806, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37336851

RESUMO

The Brazil nut shell was used as a precursor material for preparing activated carbon by chemical activation with potassium hydroxide. The obtained material (BNSAC) was characterized, and the adsorptive features of phenol were investigated. The characterization showed that the activated carbon presented several rounded cavities along the surface, with a specific surface area of 332 m2 g-1. Concerning phenol adsorption, it was favored using an adsorbent dosage of 0.75 g L-1 and pH 6. The kinetic investigation revealed that the system approached the equilibrium in around 180 min, and the Elovich model represented the kinetic curves. The Sips model well represented the equilibrium isotherms. In addition, the increase in temperature from 25 to 55 °C favored the phenol adsorption, increasing the maximum adsorption capacity value (qs) from 83 to 99 mg g-1. According to the estimated thermodynamic parameters, the adsorption was spontaneous, favorable, endothermic, and governed by physical interactions. Therefore, the Brazil nut shell proved a good precursor material for preparing efficient activated carbon for phenol removal.


Assuntos
Bertholletia , Poluentes Químicos da Água , Fenol/química , Carvão Vegetal/química , Concentração de Íons de Hidrogênio , Fenóis , Termodinâmica , Adsorção , Água , Cinética , Poluentes Químicos da Água/análise , Soluções
4.
Environ Sci Pollut Res Int ; 30(29): 73780-73798, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37193793

RESUMO

The Amazon River is the longest river in the world. The Tapajós River is a tributary to the Amazon. At their junction, a marked decrease in water quality is evident from negative impacts from the constant activity of clandestine gold mining in the Tapajós River watershed. The accumulation of hazardous elements (HEs), capable of compromising environmental quality across large regions is evident in the waters of the Tapajós. Sentinel-3B OLCI (Ocean Land Color Instrument) Level-2 satellite imagery with Water Full Resolution (WFR) of 300 m was utilized to detect the highest potential for the absorption coefficient of detritus and gelbstoff in 443 m-1 (ADG443_NN), chlorophyll-a (CHL_NN) and total suspended matter concentration (TSM_NN), at 25 points in the Amazon and Tapajós rivers (in 2019 and 2021). Physical samples of riverbed sediment collected in the field at the same locations were analyzed for NPs and ultra-fine particles to verify the geospatial findings. The riverbed sediment samples collected in the field were studied by Transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM), with selected area electron diffraction (SAED), following laboratory analytical procedures. The Sentinel-3B OLCI images, based on the Neural Network (NN) were calibrated by the European Space Agency (ESA), with a standard average normalization of 0.83 µg/mg, containing a maximum error of 6.62% applied to the sampled points. The analysis of the riverbed sediment samples revealed the presence of the following hazardous elements: As, Hg, La, Ce, Th, Pb, Pd, among several others. The Amazon River has significant potential to transport ADG443_NN (55.475 m-1) and TSM_NN (70.787 gm-3) in sediments, with the possibility of negatively impacting marine biodiversity, in addition to being harmful to human health over very large regions.


Assuntos
Mercúrio , Nanopartículas , Poluentes Químicos da Água , Humanos , Rios , Monitoramento Ambiental/métodos , Qualidade da Água , Mercúrio/análise , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise
5.
Mar Pollut Bull ; 187: 114525, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36580843

RESUMO

The Tinto River is known globally for having a reddish color due to the high concentration of dissolved metals in its waters. The general objective of this study is to analyze the dispersion of nanoparticles (NPs) and ultra-fine particles in terrestrial and geospatial suspended sediments (SSs) using Sentinel-3B OLCI (Ocean Land Color Instrument) satellite images; by examining water turbidity levels (TSM_NN), suspended pollution potential (ADG_443_NN) and presence of chlorophyll-a (CHL_NN). The images were collected in the estuary of the Tinto River, in the city of Nerva, Spanish province of Huelva, between 2019 and 2021. The following hazardous elements were identified in nanoparticles and ultra-fine particles by FE-SEM/EDS: As, Cd, Ni, V, Se, Mo, Pb, Sb and Sn. Sentinel-3B OLCI satellite images detected a 2019 TSM_NN of 23.47 g-3, and a 2021 reading of 16.38 g-3.


Assuntos
Rios , Poluentes Químicos da Água , Estuários , Metais/análise , Clorofila A , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Sedimentos Geológicos
6.
J Environ Qual ; 51(6): 1103-1117, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36039745

RESUMO

This review summarizes our current knowledge on the health and environmental impact as well as the mineralogical and geochemical composition of nanoparticles (NPs) associated with coal fires. It will furthermore recommend new sampling and characterization protocols to gain a better understanding of the various types of NPs that are formed either through high-temperature nucleation and alteration processes or via low-temperature dissolution-reprecipitation and weathering processes. Coal fires affect the immediate environment of coal-producing areas and produce positive and negative feedback to climate change through the emission of carbon- and sulfate-bearing gases and aerosols, respectively. Nanoparticles form during and after coal fires. They are composed of mainly soot and tar particles as well as amorphous phases, minerals, and complex mixtures of amorphous phases and minerals. It is recommended that NPs for mineralogical studies should be collected using impactors (a new generation of collectors for particulate matter, such as the TPS100 NP sampler) or that borosilicate filters at the openings of pipes and chambers be used to collect and measure gases emitted by coal fires. Furthermore, assemblages of NPs occurring at the mouths of coal fire vents should be examined using a combination of focused ion beam (FIB) technology and transmission electron microscopy (TEM), and those containing ion- or electron-beam sensitive phases should be examined with the corresponding cryo-techniques, such as cryo-FIB, cryo-ion mill, and cryo-TEM. The mineralogical and chemical composition of NP-bearing bulk samples should be examined with spectroscopy techniques such as X-ray photoelectron spectroscopy, 13 C nuclear magnetic resonance spectroscopy, or time-of-flight secondary ion mass spectroscopy.


Assuntos
Incêndios , Nanopartículas , Carvão Mineral , Carbono , Gases
7.
Environ Sci Pollut Res Int ; 29(45): 68547-68554, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35543787

RESUMO

The valorization of agro-industrial residues can be improved through their full use, making the production of second-generation ethanol viable. In this scenario, hydrolyzed soybean straw generated from a subcritical water process was applied to the basic fuchsin adsorption. At pH eight, a high adsorption capacity was obtained. The mass test results showed that basic fuchsin's removal and adsorption capacity could be maximized with an adsorbent dosage of 0.9 g L-1. The linear driving force model was suitable for predicting the kinetic profile, and the kinetic curves showed that equilibrium was reached with only 30 min of contact time. Besides, the Langmuir model was the best to predict the adsorption isotherms. The thermodynamic parameters revealed a spontaneous and endothermic process. At 328 K, there is maximum adsorption capacity (72.9 mg g-1). Therefore, it can be stated that this material could be competitive in terms of adsorption capacity coupled with the idea of full use of waste.


Assuntos
Poluentes Químicos da Água , Água , Adsorção , Etanol , Concentração de Íons de Hidrogênio , Cinética , Corantes de Rosanilina , Glycine max , Termodinâmica , Água/química , Poluentes Químicos da Água/química
8.
Chemosphere ; 301: 134661, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35452647

RESUMO

High amounts of phosphogypsum (PG) are generated in the production of phosphoric acid. Previous literature demonstrates that obtaining rare earth elements (REE) from PG is a promising alternative to managing this waste. However, the reported leaching efficiencies are low in most cases, or drastic leaching conditions are required. Therefore, this work aimed to study the leaching conditions of REE from PG to obtain high leaching efficiency values. Initially, a 24 factorial experimental design investigated the factors that affect the conventional acid leaching of REE from PG (leaching acid (citric and sulfuric acid), solid/liquid ratio, acid concentration, and temperature). Better leaching efficiency values of the sum of all REE (62.0% and 89.7% for citric and sulfuric acid, respectively) were obtained using an acid concentration of 3 mol L-1, solid/liquid ratio of 1/20 g mL-1, and temperature of 80 °C. Subsequently, the experiments optimization, performed through a central composite rotational design, indicated that the maximum leaching efficiency was achieved using a sulfuric acid concentration of 2.9 mol L-1, solid/liquid ratio of 1.7/20 g mL-1, and 55 °C. Under these conditions, the leaching efficiency of the sum of all REE was 90.0%. Leaching kinetics results showed that the equilibrium was reached in about 20 min for most REE. The mechanism investigation suggested that surface chemical reaction and diffusion through the boundary layer controlled the leaching.


Assuntos
Metais Terras Raras , Ácidos , Sulfato de Cálcio , Fósforo , Temperatura
9.
Environ Sci Pollut Res Int ; 29(21): 31085-31098, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35000165

RESUMO

In this work, buckwheat husks (Fagopyrum esculentum) were modified by acid treatment and posteriorly employed to remove the ketoprofen in batch adsorption. The characterization results indicated that a more irregular surface with new empty spaces was generated after acid treatment. The adsorptive process was favored at acidic pH = 3. The dosage of 0.85 g L-1 was fixed for the kinetic and isothermal tests, obtaining good removal and capacity indications. The kinetic studies were better represented by pseudo-second-order, obtaining an experimental capacity of 74.3 mg g-1 for 200 mg L-1 of ketoprofen. An increase in temperature negatively affected the adsorption isotherm curves, resulting in a maximum capacity of 194.1 mg g-1. Thermodynamic results confirmed the exothermic nature of the process with physical forces acting. The adsorbent presented high efficiency in treating a synthetic effluent containing different drugs and salts, 71.2%. Therefore, adsorbent development from buckwheat husks treated with a strong acid is an excellent alternative, given the good removal results and the low cost for its preparation.


Assuntos
Fagopyrum , Cetoprofeno , Poluentes Químicos da Água , Adsorção , Anti-Inflamatórios não Esteroides , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica , Águas Residuárias/química
10.
J Soils Sediments ; 22(6): 1773-1786, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37475891

RESUMO

Purpose: Mineralogical and geochemical features of mining and processing wastes collected in Owen County, part of the Central Kentucky Lead-Zinc district, were investigated. The Gratz mine, abandoned in the 1940s, is on a dairy farm. Aside from discerning the nature of mining refuse at the site, the investigation was part of the University of Kentucky College of Pharmacy's mission to explore unusual environments in the search for unique microbiological communities. Materials and methods: Four samples of a soil-plus-spoils mix were collected from spoil piles and two samples, the sluice and coarse samples, were closely associated with the site of the ore processing. Optical petrology (polarized reflected-light, oil-immersion optics at a final magnification of 500 ×), X-ray diffraction, X-ray fluorescence, inductively coupled plasma mass spectrometry, field emission scanning electron microscopy (FE-SEM), and high-resolution transmission electron microscope (HR-TEM) with selected area electron diffraction (SAED) and/or microbeam diffraction (MBD), scanning transmission electron microscopy (STEM), and energy-dispersive X-ray spectrometer (EDS) analyses were employed to characterize the samples. Results and discussion: Calcite is the main mineral in most samples, followed by near equal amounts of quartz and dolomite. Sphalerite and galena are the principal sulfides and barite is the dominant sulfate. Geochemistry of major elements reflected the mineralogy, whereas trace elements showed different groupings between the minerals. Scandium, Cu, Ga, Ge, Cd, and Sb were found predominantly associated with Zn and Pb and sulfide minerals; Bi, Hf, In, Sn, and Zr with heavy mineral fraction; while the remaining trace elements, including the rare earths, were mostly distributed among other present phases, i.e., oxyhalides, oxides, silicates, and carbonaceous material. The data were used to illustrate the processes and conditions that control the sulfide-mineral oxidation and its potential for the environmental release of associated reaction products. Conclusions: The wastes represent a potential source of environmentally disruptive concentrations of Zn, Pb, and other sulfide-associated elements. The high share of carbonates suggests near-neutral conditions in deposited wastes, restricting sulfide weathering and further limiting the oxidant activity of Fe. The low-Fe content and its predominant presence in highly resistant hematite also constrain sulfide weathering. Consequently, the spoils have a low potential for generation of acidity and release of heavy metal(loid)s in the surrounding environment.

11.
Geosci Front ; 13(6): 101373, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37521134

RESUMO

The novel coronavirus, SARS-CoV-2, which has caused millions of death globally is recognized to be unstable and recalcitrant in the environment, especially in the way it has been evolving to form new and highly transmissible variants. Of particular concerns are human-environment interactions and the handling and reusing the environmental materials, such as effluents, sludge, or biosolids laden with the SARS-CoV-2 without adequate treatments, thereby suggesting potential transmission and health risks. This study assesses the prevalence of SARS-CoV-2 RNA in effluents, sludge, and biosolids. Further, we evaluate the environmental, ecological, and health risks of reusing these environmental materials by wastewater/sludge workers and farmers. A systematic review of literature from the Scopus database resulted in a total of 21 articles (11 for effluents, 8 for sludge, and 2 for biosolids) that met the criteria for meta-analysis, which are then subdivided into 30 meta-analyzed studies. The prevalence of SAR-CoV-2 RNA in effluent and sludge based on random-effect models are 27.51 and 1012.25, respectively, with a 95% CI between 6.14 and 48.89 for the effluent, and 104.78 and 1019.71 for the sludge. However, the prevalence of SARS-CoV-2 RNA in the biosolids based on the fixed-effect model is 30.59, with a 95% CI between 10.10 and 51.08. The prevalence of SARS-CoV-2 RNA in environmental materials indicates the inefficiency in some of the treatment systems currently deployed to inactivate and remove the novel virus, which could be a potential health risk concern to vulnerable wastewater workers in particular, and the environmental and ecological issues for the population at large. This timely review portends the associated risks in handling and reusing environmental materials without proper and adequate treatments.

12.
Chemosphere ; 286(Pt 1): 131513, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34284899

RESUMO

Many industrial by-products have been disposed along coastlines, generating profound marine changes. Phosphogypsum (PG) is a solid by-product generated in the production of phosphoric acid (PA) using conventional synthesis methods. The raw material, about 50 times more radioactive as compared to unperturbed soils, is dissolved in diluted sulfuric acid (70%) forming PG and PA. The majority of both, reactive hazardous elements and natural radionuclides, remain bound to the PG. A nonnegligible fraction of PG occurs as nanoparticles (<0.1 µm). When PG are used for e.g., agriculture or construction purposes, nanoparticles (NPs) can be re-suspended by Aeolian and fluvial processes. Here we provide an overview and evaluation of the geochemical and radiological hazardous risks associated with the different uses of PG. In this review, we show that NPs are important residues in both raw and waste materials originating from the uses of phosphate rock. Different industrial processes in the phosphate fertilizer industries are discussed in the context of the chemical and mineralogical composition as well as size and reactivity of the released NP. We also review how incidental NPs of PG impact the global environment, especially with respect to the distribution of rare earth elements (REEs), toxic elements such as As, Se, and Pb, and natural radionuclides. We also propose the application of advanced techniques and methods to better understand formation and transport of NPs containing elements of high scientific, economic, and environmental importance.


Assuntos
Sulfato de Cálcio , Nanopartículas , Fertilizantes/análise , Fósforo , Solo
13.
Geosci Front ; 13(6): 101310, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36896207

RESUMO

Urban cemeteries are increasingly surrounded by areas of high residential density as urbanization continues world-wide. With increasing rates of mortality caused by the novel coronavirus, SARS-CoV-2, urban vertical cemeteries are experiencing interments at an unprecedented rate. Corpses interred in the 3rd to 5th layer of vertical urban cemeteries have the potential to contaminate large adjacent regions. The general objective of this manuscript is to analyze the reflectance of altimetry, normalized difference vegetation index (NDVI) and land surface temperature (LST) in the urban cemeteries and neighbouring areas of the City of Passo Fundo, Rio Grande do Sul, Brazil. It is assumed that the population residing in the vicinity of these cemeteries may be exposed to SARS-CoV-2 contamination through the displacement of microparticles carried by the wind as a corpse is placed in the burial niche or during the first several days of subsequent fluid and gas release through the process of decomposition. The reflectance analyses were performed utilizing Landsat 8 satellite images applied to altimetry, NDVI and LST, for hypothetical examination of possible displacement, transport and subsequent deposition of the SARS-CoV-2 virus. The results showed that two cemeteries within the city, cemeteries A and B could potentially transport SARS-CoV-2 of nanometric structure to neighboring residential areas through wind action. These two cemeteries are located at high relative altitudes in more densely populated regions of the city. The NDVI, which has been shown to control the proliferation of contaminants, proved to be insufficient in these areas, contributing to high LST values. Based on the results of this study, the formation and implementation of public policies that monitor urban cemeteries is suggested in areas that utilize vertical urban cemeteries in order to reduce the further spread of the SARS-CoV-2 virus.

14.
Geosci Front ; 13(6): 101279, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38620951

RESUMO

The novel coronavirus, SARS-CoV-2, has the potential to cause natural ventilation systems in hospital environments to be rendered inadequate, not only for workers but also for people who transit through these environments even for a limited duration. Studies in of the fields of geosciences and engineering, when combined with appropriate technologies, allow for the possibility of reducing the impacts of the SARS-CoV-2 virus in the environment, including those of hospitals which are critical centers for healthcare. In this work, we build parametric 3D models to assess the possible circulation of the SARS-CoV-2 virus in the natural ventilation system of a hospital built to care infected patients during the COVID-19 pandemic. Building Information Modeling (BIM) was performed, generating 3D models of hospital environments utilizing Revit software for Autodesk CFD 2021. The evaluation considered dimensional analyses of 0°, 45°, 90° and 180°. The analysis of natural ventilation patterns on both internal and external surfaces and the distribution of windows in relation to the displacement dynamics of the SARS-CoV-2 virus through the air were considered. The results showed that in the external area of the hospital, the wind speed reached velocities up to 2.1 m/s when entering the building through open windows. In contact with the furniture, this value decreased to 0.78 m/s. In some internal isolation wards that house patients with COVID-19, areas that should be equipped with negative room pressure, air velocity was null. Our study provides insights into the possibility of SARS-CoV-2 contamination in internal hospital environments as well as external areas surrounding hospitals, both of which encounter high pedestrian traffic in cities worldwide.

15.
Mar Pollut Bull ; 173(Pt A): 112925, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34534938

RESUMO

The analysis of marine matter using the Sentinel-3B OLCI (Ocean Land Color Instrument) satellite is the most advanced technique for evaluating: the absorption of colored detrital and dissolved material (ADG_443_NN), total suspended matter concentration (TSM_NN) and of chlorophyll-a (CHL_NN) on a global scale. The objective is to analyze ADG_443_NN, TSM_NN and CHL_NN using the Sentinel-3B OLCI satellite and the presence of Fe-nanoparticles (NPs) + hazardous elements (HEs) in suspended sediments (SSs) in the maritime estuary of the Colombian city of Barranquilla. The study used the unpublished image of the Sentinel-3B OLCI satellite in the evaluation of ADG_443_NN, TSM_NN and CHL_NN in 72 sampled points. Subsequently, 36 samples of SSs were carried out in the Magdalena River, in the identification of Fe-NPs by advanced electron microscopies. The Sentinel-3B satellite revealed particulate accumulations in OCE1 through the intensity of OLCI in ocean. There was also a high Fe-NPs intensity of SSs in the Magdalena channel, spreading contamination to large regions.


Assuntos
Estuários , Nanopartículas , Monitoramento Ambiental , Ferro , Rios
16.
Mar Pollut Bull ; 168: 112429, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33962087

RESUMO

Studding the behaviour and danger of nanoparticles (NPs, minerals and amorphous phases) in the estuarine ecosystem is presently incomplete by the lack of measureable description of NPs in the ecological conditions, such as suspended-sediments (SS). In the last years, several works have revealed the toxic consequences of ultra-fine and nanoparticulate compounds on diverse systems, raising apprehensions over the nanocontaminants behaviour and destiny in the numerous ecological partitions. The general objective of the manuscript is to explain the geochemical conditions of the LES (Laguna estuarine system, southern Brazil) suspended sediments covering an area around the main South American coal plant, enhancing the creation of future public policies for environmental recovery projects. Subsequently the discharge of nanoparticles and toxic element (TE) in the ecosystem, NPs react with several constituents of the nature and suffers active alteration progressions. Contamination coming from engineering actions, wastewater, are something identifiable, however when these contaminations are accompanied by other contamination sources (e.g. mining and farming) the work gets defaulted. By combining material about the concentration of TE contaminants and NPs occurrences, this work offers novel visions into contaminant contact and the possible effects of such exposure on estuarine systems in Brazil. The results presented here will be useful for different areas of estuaries around the world.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Brasil , Ecossistema , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Poluentes Químicos da Água/análise
17.
Mar Pollut Bull ; 169: 112493, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34022554

RESUMO

Anthropogenic occurring nanoparticles (NPs) have been one of the principal catalytic components of marine pollution throughout its history. The phosphogypsum (PG) factories present environmental risks and evident marine pollution in different parts of the world. Many of these factors continue to operate, however, some have already been abandoned by the private sector. The general objective of this manuscript is to analyze the real nanoparticles (NPs) present on a beach in southern Brazil to illustrate the need to create public policies and projects for environmental recovery. This work focused on real representative sampling of suspended sediments (SSs), and on a modern analytical procedure via advanced electron microscopes (field emission scanning electron microscope-FE-SEM and high resolution transmission electron microscope-HR-TEM coupled with an energy dispersive X-ray microanalysis system-EDS) to analyze NPs containing hazardous elements (HEs). The results presented in this work demonstrate who the size, morphology, among other physical-geochemical characteristics influence in the adsorption of HEs by the NPs and their respective agglomerates. This study is of great importance for carrying out the application of advanced techniques and methods to better understand the formation and transport of NPs on beaches, which allows assisting in the management of waste from plaster factories on a global scale.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Brasil , Sulfato de Cálcio , Monitoramento Ambiental , Fósforo
18.
Mar Pollut Bull ; 168: 112425, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33940370

RESUMO

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.


Assuntos
Ecossistema , Nanopartículas , Região do Caribe , Monitoramento Ambiental , Alocação de Recursos
19.
Mar Pollut Bull ; 168: 112405, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33940373

RESUMO

Studies examining nanoparticles (NPs) and hazardous elements (HEs) contained in suspended sediments (SSs) are vital for watershed administration and ecological impact evaluation. The biochemical consequence of titanium-nanoparticles (Ti-NPs) from SSs in Colombia's Magdalena River was examined utilizing an innovative approach involving nanogeochemistry in this study. In general, the toxicity and the human health risk assessment associated with the presence of some Ti-NPs + HEs in SSs from riverine systems need to be determined with a robust analytical procedure. The mode of occurrence of Ti-NPs, total Ti and other elements contained within SSs of the Magdalena River were evaluated through advanced electron microscopy (field emission scanning electron microscope-FE-SEM and high resolution transmission electron microscope-HR-TEM) coupled with an energy dispersive X-ray microanalysis system (EDS); X-Ray Diffractions (XRD); and inductively coupled plasma-mass spectrometry (ICP-MS). This work showed that enormous quantities of Ti-NPs were present in the river studied and that they displayed diverse geochemical properties and posed various possible ecological dangers. Ti-NP contamination indices must be established for measuring the environmental magnitudes of NP contamination and determining contamination rank among rivers. Finally, SS contamination guidelines must be recommended on an international level. This study contributes to the scientific understanding of the relationship of HE and Ti-NP dynamics from SSs in riverine systems around the world.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Sedimentos Geológicos , Humanos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Rios , Titânio
20.
Chemosphere ; 277: 130286, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33770688

RESUMO

Historic buildings that comprise the cultural heritage of humanity are in need of preservation on a worldwide scale in regard to degradation resultant from atmospheric pollutants. The Brazilian Public Market, located in the historic center of the mega city of São Paulo, is the object of this research, due to its representation of historical Brazilian architecture. The general objective of this manuscript is to analyze the influence of air pollutants on the degradation of the historic São Paulo Public Market in the city of São Paulo, Brazil. Methodologically, between May 2018 and April 2019, samples of sedimented dust were collected at five points on the side walls of the market's historic structure, for the analysis of accumulated ultrafine particles (UFPs) and nanoparticles (NPs). A total of 20 samples of particulate matter were collected using self-made passive samplers (SMPSs). Using SMPSs, 12 months of accumulation and deposition were used to sample the atmospheric PM1. The results demonstrate the presence of dangerous elements such as: As, Cd, Cr, Pb, Zn. Note that EDS coupled with microscopy techniques, points out the risks to human health, due to the presence of these dangerous elements that accumulate in the building's structure. The results show that 85% of the NPs sampled contained Pb, and 56% contained Pb and Ti, which are harmful to both historic buildings and human health. Air pollution enables the further deterioration of the São Paulo Public Market, which is in need of restoration.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Brasil , Cidades , Monitoramento Ambiental , Humanos , América Latina , Material Particulado/análise
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