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1.
Sci Total Environ ; 806(Pt 3): 151286, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-34743816

ABSTRACT

COVID-19 has escalated into one of the most serious crises in the 21st Century. Given the rapid spread of SARS-CoV-2 and its high mortality rate, here we investigate the impact and relationship of airborne PM2.5 to COVID-19 mortality. Previous studies have indicated that PM2.5 has a positive relationship with the spread of COVID-19. To gain insights into the delayed effect of PM2.5 concentration (µgm-3) on mortality, we focused on the role of PM2.5 in Wuhan City in China and COVID-19 during the period December 27, 2019 to April 7, 2020. We also considered the possible impact of various meteorological factors such as temperature, precipitation, wind speed, atmospheric pressure and precipitation on pollutant levels. The results from the Pearson's correlation coefficient analyses reveal that the population exposed to higher levels of PM2.5 pollution are susceptible to COVID-19 mortality with a lag time of >18 days. By establishing a generalized additive model, the delayed effect of PM2.5 on the death toll of COVID-19 was verified. A negative correction was identified between temperature and number of COVID-19 deaths, whereas atmospheric pressure exhibits a positive correlation with deaths, both with a significant lag effect. The results from our study suggest that these epidemiological relationships may contribute to the understanding of the COVID-19 pandemic and provide insights for public health strategies.


Subject(s)
Air Pollutants , Air Pollution , COVID-19 , Air Pollutants/analysis , Air Pollutants/toxicity , Air Pollution/adverse effects , Air Pollution/analysis , China/epidemiology , Humans , Pandemics , Particulate Matter/analysis , Particulate Matter/toxicity , SARS-CoV-2
2.
Mar Pollut Bull ; 168: 112425, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33940370

ABSTRACT

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.


Subject(s)
Ecosystem , Nanoparticles , Caribbean Region , Environmental Monitoring , Resource Allocation
3.
Chemosphere ; 191: 1048-1055, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28923475

ABSTRACT

The present study is focused on the chemical and nano-mineralogical characterization of sludge from gold mine activities, in order to put forward diverse solution alternatives, where lack of knowledge has been found. The sample was collected from "La Estrella" mine of Suarez, located in Department of Cauca, south-west Colombia. The sludge micro-structure and chemical composition were analyzed using a high resolution transmission electron microscopy (HR-TEM) equipped with a dispersive X-ray detector (EDS). X-ray diffraction technique was employed to identify the mineralogical phases present in the sludge. Additional mineralogical characterization was done by using RAMAN spectroscopy. Main findings points to its potential to be used as a fertilizer, this is why, mine sludge contains macronutrients such as P, Ca and S, together with micronutrients like Cu. However, the presence of goethite could decrease the mobilization of nutrients to soils, thus additional alternatives, for instance, a mixture with humus or another material containing Humic Acids should be done, in order to minimizing its retention effect. Additionally, another possible uses to explore could be as construction and ceramic material or in the wastewater treatment for nutrient retention and organic material removal. Rutile (TiO2 nanoparticles) particles have been also detected, what could cause health concern due to its nanoparticle toxic character, mainly during gold extraction process.


Subject(s)
Gold , Mining , Nanostructures/chemistry , Sewage/analysis , Colombia , Environmental Restoration and Remediation/methods , Fertilizers , Iron Compounds , Microscopy, Electron, Transmission , Minerals , Nanostructures/ultrastructure , Sewage/chemistry , Soil , Titanium/analysis , X-Ray Diffraction
4.
J Hazard Mater ; 346: 263-272, 2018 03 15.
Article in English | MEDLINE | ID: mdl-29288979

ABSTRACT

Coal processing generates a large volume of waste that can damage human health and the environment. Often these wastes produce acid drainage in which several minerals are crystallized (evaporites). This study aimed to identify secondary minerals, as well as the genotoxic potential of these materials. The samples were collected at two sites along the Rocinha River in Santa Catarina state (Brazil): (1) directly from the source of the acid drainage (evaporite 1), and (2) on the river bank (evaporite 2). The samples were characterized by X-ray diffraction and by particle-induced X-ray emission techniques. In vitro genotoxicity testing using Comet assay and Micronucleus test in V79 cells was used to evaluate evaporite samples. Our study also used System Biology tools to provide insight regarding the influence of this exposure on DNA damage in cells. The results showed that the samples induced DNA damage for both evaporites that can be explained by high concentrations of chromium, iron, nickel, copper and zinc in these materials. Thus, this study is very important due to the dearth of knowledge regarding the toxicity of evaporites in the environment. The genetic toxicity of this material can be induced by increased oxidative stress and DNA repair inhibition.


Subject(s)
Coal Mining , Industrial Waste/adverse effects , Metals, Heavy/toxicity , Minerals/toxicity , Water Pollutants, Chemical/toxicity , Animals , Cell Line , Cell Survival/drug effects , Comet Assay , Cricetulus , Crystallization , DNA Damage , Metals, Heavy/analysis , Micronucleus Tests , Minerals/analysis , Water Pollutants, Chemical/analysis
5.
Environ Res ; 160: 562-567, 2018 01.
Article in English | MEDLINE | ID: mdl-29173343

ABSTRACT

Pollution generated by hazardous elements and persistent organic compounds that affect coal fire is a major environmental concern because of its toxic nature, persistence, and potential risk to human health. The coal mining activities are growing in the state of Santa Catarina in Brazil, thus the collateral impacts on the health and economy are yet to be analyzed. In addition, the environment is also enduring the collateral damage as the waste materials directly influence the coal by-products applied in civil constructions. This study was aimed to establish the relationships between the composition, morphology, and structural characteristics of ultrafine particles emitted by coal mine fires. In Brazil, the self-combustions produced by Al-Ca-Fe-Mg-Si coal spheres are rich in chalcophile elements (As, Cd, Cu, Hg, Pb, Sb, Se, Sn, and Zn), lithophile elements (Ce, Hf, In, La, Th, and U), and siderophile elements (Co, Cr, Mo, Fe, Ni, and V). The relationship between nanomineralogy and the production of hazardous elements as analyzed by advanced methods for the geochemical analysis of different materials were also delineated. The information obtained by the mineral substance analysis may provide a better idea for the understanding of coal-fire development and assessing the response of particular coal in different combustion processes.


Subject(s)
Coal , Environmental Exposure , Environmental Monitoring/methods , Hazardous Substances/analysis , Mining , Particulate Matter/analysis , Brazil , Hazardous Substances/classification , Humans , Particle Size , Risk Assessment , Spontaneous Combustion
6.
Environ Res ; 158: 450-455, 2017 10.
Article in English | MEDLINE | ID: mdl-28692927

ABSTRACT

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.


Subject(s)
Air Pollutants/analysis , Coal , Environmental Exposure , Particulate Matter/analysis , Brazil , Environmental Monitoring , Humans , Nanoparticles/analysis , Nanoparticles/ultrastructure , Particle Size , Power Plants
7.
Chemosphere ; 169: 725-733, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27720476

ABSTRACT

Soils around coal mining are important reservoir of hazardous elements (HEs), nanominerals, and ultrafine compounds. This research reports and discusses the soil concentrations of HEs (As, Cd, Cr, Cu, Ni, Pb, and Zn) in coal residues of abandoned mines. To assess differences regarding environmental impact and risk assessment between coal abandoned mines from the Santa Catarina state, eighteen coal cleaning rejects with different mineralogical and chemical composition, from eight abandoned mines were collected. Nanominerals and ultra-fine minerals from mining-contaminated areas were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and high-resolution transmission electron microscope (HR-TEM), providing new information on the mineralogy and nano-mineralogy of these coal residues. The total contents of 57 elements (HEs, alkali metals, and rare earth elements) were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The calculation of NWACs (Normalized Average Weighted Concentration), together with the chemometric analysis by Principal component analysis (PCA) confirmed the variability of the samples regarding their city and their mine of origin. Moreover, the results confirmed the existence of hotspots in mines near urban areas.


Subject(s)
Coal Ash/analysis , Coal/analysis , Environmental Monitoring/methods , Minerals/analysis , Mining , Risk Assessment/methods , Brazil , Hazardous Waste , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Nanoparticles/chemistry , Soil , Soil Pollutants/analysis , X-Ray Diffraction
8.
Chemosphere ; 147: 439-43, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26774310

ABSTRACT

Detailed geochemistry similarities between the burning coal cleaning rejects (BCCRs) and non-anthropogenic geological environments are outlined here. While no visible flames were detected, this research revealed that auto-combustion existed in the studied area for many years. The occurrence of several amorphous phases, mullite, hematite and many other Al/Fe-minerals formed by high temperature was found. Bad disposal of coal-dump wastes represents significant environmental concerns due to their potential influence on atmosphere, river sediments, soils and as well as on the surface and groundwater in the surroundings of these areas. The present work using multi-analytical techniques were performed to provide an improved understanding of the complex processes related with sulphide-rich coal waste oxidation, spontaneous combustion and newmineral creation. It recording huge numbers of rare minerals with alunite, montmorillonite, szmolnockite, halotrichite, coquimbite and copiapite at the BCCRs. The information presented the presence of abundant amorphous Si-Al-Fe-Ti as (oxy-)hydroxides and Fe-hydro/oxides with goethite and hematite with various degrees of crystallinity, containing potential hazardous elements (PHEs), such as Cu, Cr, Hf, Hg, Mo, Ni, Se, Pb, Th, U, Zr, and others. Most of the nano-particles and ultra-fine particles found in the burned coal-dump wastes are the same as those commonly associated with coal cleaning rejects, in which oxidation of sulphides plays an important impact to environment and subsequently animal and human health.


Subject(s)
Coal , Environmental Pollutants/analysis , Industrial Waste/analysis , Nanoparticles/analysis , Environment , Environmental Monitoring/methods , Metals, Heavy/analysis
9.
Environ Monit Assess ; 174(1-4): 187-97, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20422282

ABSTRACT

Environmental and human health risk assessments of nanoparticle effects from coal and bottom ash require thorough characterisation of nanoparticles and their aggregates. In this manuscript, we expand the study of human exposure to nanosized particles from coal combustion sources (typically <100 nm in size), characterising the complex micromineralogy of these airborne combustion-derived nanomaterials. Our study focuses on bottom ash generated in the Santa Catarina power station (Brazil) which uses coal enriched in ashes, many potential elements (e.g. Cr and Ni) and pyrite. Transmission electron microscope data reveal nanoscale C deposits juxtaposed with and overgrown by slightly larger aluminosilicate (Al-Si) glassy spheres, oxides, silicates, carbonated, phosphates and sulphates. Iron oxides (mainly hematite and magnetite) are the main bottom ash products of the oxidation of pyrite, sometimes via intermediate pyrrhotite formation. The presence of iron oxide nanocrystals mixed with silicate glass particles emphasises the complexity of coal and bottom ash micromineralogy. Given the potentially bioreactive nature of such transition metal-bearing materials, there is likely to be an increased health risk associated with their inhalation.


Subject(s)
Coal , Minerals/chemistry , Nanoparticles , Humans
10.
Diabetes Metab Syndr ; 5(2): 66-70, 2011.
Article in English | MEDLINE | ID: mdl-22813405

ABSTRACT

INTRODUCTION: Factors leading to weight loss and weight stabilization after bariatric surgery are not fully understood. Our aim was to evaluate, in Sprague-Dawley rats, the histological and gut hormonal changes after Larrad-biliopancreatic diversion (Larrad-BPD). MATERIALS AND METHODS: Rats randomly underwent the following protocols: Larrad-BPD (n=4) versus pair fed (PF) (n=4). Weight and food intake were measured every day. By immunohistochemistry ghrelin was examined in the stomach, while cholecystokinin (CCK), glucagon-like-peptide-1 (GLP-1), peptide YY (PYY) and serotonin (5-HT) expression were analyzed in alimentary limb and ileum following or not the Larrad-BPD. RESULTS: Larrad-BPD rats exhibited significant (P<0.05) weight loss compared to PF rats. Villi enlongation was observed in Larrad-BPD rats. In residual stomach, ghrelin was diminished. In the alimentary limb, ghrelin and CCK positive cells were detected more than in the ileum of PF rats. GLP-1 expression was decreased and PYY expression was absent after Larrad-BPD compared with PF rats. DISCUSSION: Larrad-BPD is followed by histological changes and a pleiotropic gut endocrine response aimed to compensate the reduction of intestinal area exposed to food. Until now, the hormones responsible for the intestinal hypertrophy have not been defined.


Subject(s)
Biliopancreatic Diversion/trends , Cholecystokinin/biosynthesis , Gastric Mucosa/metabolism , Ghrelin/biosynthesis , Intestinal Mucosa/metabolism , Animals , Biliopancreatic Diversion/methods , Body Weight/physiology , Energy Intake/physiology , Gastric Mucosa/cytology , Gastric Mucosa/physiopathology , Intestinal Mucosa/cytology , Intestinal Mucosa/physiopathology , Male , Rats , Rats, Sprague-Dawley
11.
Front Horm Res ; 38: 196-205, 2010.
Article in English | MEDLINE | ID: mdl-20616512

ABSTRACT

Ghrelin, a peptide hormone first discovered as the endogenous ligand of the growth hormone secretagogue receptor (GHS-R), is predominantly produced and released into the circulation by ghrelin cells (X/A-like) of the stomach fundus cells. Ghrelin has multiple actions in multiple tissues. In particular, it is the most potent known endogenous orexigenic peptide, and plays a significant role in glucose homeostasis: deletion of the genes encoding ghrelin and/or its receptor prevents high-fat diet from inducing obesity, increases insulin levels, enhances glucose-stimulated insulin secretion and improves peripheral insulin sensitivity. In addition to its already mentioned roles, ghrelin has other activities including stimulation of pituitary hormones secretion, regulation of gastric and pancreatic activity, modulation of fatty acid metabolism via specific control of AMP-activated protein kinase (AMPK), and cardiovascular and hemodynamic activities. In addition, modulation of cartilage and bone homeostasis, sleep and behavioral influences, and modulation of the immune system, as well as effects on cell proliferation, are other relevant actions of ghrelin. In this review, we summarize several aspects of ghrelin effects at hypothalamic level and their implications in the control of food intake and energy balance.


Subject(s)
Ghrelin/physiology , Agouti-Related Protein/physiology , Animals , Body Weight , Eating , Homeodomain Proteins/physiology , Humans , Hypothalamus/metabolism , Lipid Metabolism , Neuropeptide Y/physiology , Receptors, Ghrelin/physiology
12.
Obes Surg ; 19(4): 484-9, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18855085

ABSTRACT

BACKGROUND: Existing medical therapeutic strategies to achieve and maintain clinically significant weight loss in morbid obesity remain limited and the biliopancreatic diversion (BPD) is still the most effective among the bariatric surgical procedures. Our objective was to evaluate the weight and food intake after this procedure in a rat model. METHODS: Rats randomly underwent one of the following protocols (1) BPD (n = 12) versus sham (n = 12) with a follow-up period of 30 days and (2) BPD (n = 4) versus pair-fed (PF; n = 4) with a follow-up period of 50 days. Under intraperitoneal anesthesia with ketamine-xilacine, a subcardinal corpo-antral gastrectomy was made, preserving the gastric fundus that was anastomosed to a jejunal limb after dissecting the proximal jejunum 5 cm below the ligament of Treitz to form the alimentary limb. The biliopancreatic limb was terminolaterally anastomosed to the distal ileum 5 cm above the ileocecal valve to form the common limb. Sham animals underwent only abdominal incision. Weight and food intake were measured every day. RESULTS: In protocol 1, after postoperative day 30, BPD rats exhibited a mean weight reduction of 17.9% while shams increased 12.4%. There was no difference in food intake adjusted per 100 g of body weight. In protocol 2, after postoperative day 50, BPD rats had a mean weight reduction of 22.6% and, despite increasing their caloric intake from a mean of 42.6 after 6 days to 65.8 kcal/day after 50 days, they kept a similar mean weight of 344.0 and 340.2 g, respectively; on the contrary, PF rats exhibited a 30.8% body weight gain. CONCLUSIONS: After the BPD, body weight is maintained independently of changes in food and energy intake.


Subject(s)
Biliopancreatic Diversion/methods , Eating , Weight Loss , Animals , Energy Intake , Gastric Bypass , Male , Postoperative Period , Rats , Rats, Sprague-Dawley
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