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1.
Rev Bras Epidemiol ; 26: e230010, 2023.
Artigo em Inglês, Português | MEDLINE | ID: mdl-36722666

RESUMO

OBJECTIVE: To describe, within the Human Rights to Water and Sanitation (HRWS) framework, the access to water supply services and the incidence of waterborne diseases in the communities affected by the dam disaster in Brumadinho (MG), Brazil. METHODS: A quantitative and qualitative methodology was used, having as variables information on access to water supply services and waterborne diseases. The primary data were extracted from the "Brumadinho Health Project", using a sample stratum with 981 people interviewed, totaling 92.5% of the eligible population in the affected communities of Córrego do Feijão and Parque da Cachoeira. The secondary data from Brumadinho was extracted from the project "Sanitation conditions and the River Basin of the B1 River Basin of Mineradora Vale between 2017 and 2020", available in public databases between 2017 and 2020, and qualitative data was collected in 2022 through individual interviews with health professional also live in the communities. RESULTS: With regard to access to water supply services, the results of this combined data analysis indicate that the HRWS is being neglected, especially with regard to availability, accessibility, acceptability and quality of water. The study also shows a significant increase in the incidence of waterborne diseases in the region after the disaster. CONCLUSION: It is necessary to use the HRWS as the basis to the implementation of public policies aiming to reduce vulnerability in access to water supply services.


Assuntos
Colapso Estrutural , Doenças Transmitidas pela Água , Humanos , Brasil/epidemiologia , Incidência , Doenças Transmitidas pela Água/epidemiologia , Água
2.
Sci Total Environ ; 865: 161278, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36592904

RESUMO

The rupture of the Córrego do Feijão dam in Brumadinho (January 25, 2019) caused serious damage to the Paraopeba River and compromised the quality of its waters for human consumption. However, the possible effects of the dam collapse on the river microbiome and its antibiotic resistance profiles are unknown. The present study aims to analyse the possible shifts in microbial diversity and enhancement of antibiotic resistance in the Paraopeba River. To this end, two sampling campaigns (February and May 2019) were performed to obtain water across the entire Paraopeba River (eight sampling locations: Moeda, Brumadinho, Igarapé, Juatuba, Varginha, Angueretá, Retiro Baixo and Três Marias; ~464 km). This sampling scheme enabled determining the effects of the disaster on the river microbiome. Total DNA and microbial isolation were performed with these water samples. The 16S rRNA-based microbiome analyses (n = 24; 2.05 million 16S rRNA reads) showed changes in microbial diversity immediately after the disaster with the presence of metal-indicating bacteria (Acinetobacter, Bacillus, Novosphingobium, and Sediminibacterium). Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) identification of bacterial isolates (n = 170) also disclosed possible indicators of faecal contamination across the Paraopeba (Cloacibacterium, Bacteroides, Feaecalibacterium, Bifidobacterium, Citrobacter, Enterobacter, Enterococcus and Escherichia). Antibiotic resistance increased significantly to ampicillin, ampicillin/sulbactam, amoxicillin/clavulanate, ceftriaxone, and cefalotin among isolates obtained in May after the disaster. The effects of toxic mud on microbiomes were felt at all points sampled up to Anguereta. The ore mud may have exacerbated the growth of different antibiotic-resistant, metal-resistant, and faecal-indicating bacteria in the Paraopeba River.


Assuntos
Microbiota , Colapso Estrutural , Poluentes Químicos da Água , Humanos , Rios/microbiologia , RNA Ribossômico 16S/genética , Brasil , Bactérias/genética , Poluentes Químicos da Água/análise , Resistência Microbiana a Medicamentos , Água/análise , Ampicilina/análise , Monitoramento Ambiental
4.
Sensors (Basel) ; 22(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35890756

RESUMO

This paper presents a field implementation of the structural health monitoring (SHM) of fatigue cracks for steel bridge structures. Steel bridges experience fatigue cracks under repetitive traffic loading, which pose great threats to their structural integrity and can lead to catastrophic failures. Currently, accurate and reliable fatigue crack monitoring for the safety assessment of bridges is still a difficult task. On the other hand, wireless smart sensors have achieved great success in global SHM by enabling long-term modal identifications of civil structures. However, long-term field monitoring of localized damage such as fatigue cracks has been limited due to the lack of effective sensors and the associated algorithms specifically designed for fatigue crack monitoring. To fill this gap, this paper proposes a wireless large-area strain sensor (WLASS) to measure large-area strain fatigue cracks and develops an effective algorithm to process the measured large-area strain data into actionable information. The proposed WLASS consists of a soft elastomeric capacitor (SEC) used to measure large-area structural surface strain, a capacitive sensor board to convert the signal from SEC to a measurable change in voltage, and a commercial wireless smart sensor platform for triggered-based wireless data acquisition, remote data retrieval, and cloud storage. Meanwhile, the developed algorithm for fatigue crack monitoring processes the data obtained from the WLASS under traffic loading through three automated steps, including (1) traffic event detection, (2) time-frequency analysis using a generalized Morse wavelet (GM-CWT) and peak identification, and (3) a modified crack growth index (CGI) that tracks potential fatigue crack growth. The developed WLASS and the algorithm present a complete system for long-term fatigue crack monitoring in the field. The effectiveness of the proposed time-frequency analysis algorithm based on GM-CWT to reliably extract the impulsive traffic events is validated using a numerical investigation. Subsequently, the developed WLASS and algorithm are validated through a field deployment on a steel highway bridge in Kansas City, KS, USA.


Assuntos
Tecnologia de Sensoriamento Remoto , Aço , Colapso Estrutural , Humanos
5.
Environ Monit Assess ; 194(6): 410, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35532857

RESUMO

A great amount of iron ore tailings from the collapse of the Fundão dam in Southeast Brazil was deposited in an extensive agricultural area. The presence of this material creates insecurity for the resumption of agricultural activities, especially the cultivation of vegetables, which can accumulate metals at potentially toxic levels. In this study, two vegetables consumed in the affected area, arugula and radish, were cultivated in tailings and in soil. Productivity, photosynthetic pigment content, photosynthetic performance, metal accumulation, and the possible risk to food safety were analyzed. The productivity of both vegetables, arugula and radish, did not differ between cultivation in tailings and in soil. There were no differences in pigment content nor substantial differences in the photosynthetic parameters of plants grown in the two substrates. Plants grown in tailings had higher Fe, Mn, and Na contents than those grown in soil, reflecting the higher levels of these elements in the former. There were no visual signs of metal toxicity for plants grown in the tailings. The levels of metals potentially ingested through estimated consumption of arugula and radish grown in the tailings were below the maximum allowable limits for human consumption. In addition, calculated risk indices suggest a low potential for harm to the health of consumers of cultivated vegetables in the tailings. The results presented here suggest that agricultural cultivation in the tailings is viable and contribute to the resumption of vegetable cultivation in the region affected by the tailings released with the collapse of the Fundão dam.


Assuntos
Metais Pesados , Poluentes do Solo , Colapso Estrutural , Brasil , Monitoramento Ambiental , Inocuidade dos Alimentos , Humanos , Metais , Metais Pesados/análise , Plantas , Solo , Poluentes do Solo/análise , Verduras
6.
Sci Total Environ ; 822: 153661, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35122845

RESUMO

Flash floods are common manifestations of extreme weather events and one of the most severe natural hazards. In Europe, they have been responsible for 359 fatalities and an economic loss totalling 67 million USD in the past decade (EM-DAT), while their increasing severity is linked to climate change. Nevertheless, flash floods remain a poorly documented natural phenomenon due to the lack of flow intensity data in many of the affected watersheds. Based on a thorough field investigation, including UAV-based 3D mapping and material characterization with on-site testing, we carry out a numerical study of a notable flood that caused the collapse of bridges and buildings in Central Greece, following a recent Mediterranean hurricane. Focusing on a carefully selected case study, we combine 3D modelling of flow-structure interaction with detailed mechanical modelling of the nonlinear structural response to reproduce the flood-induced fracture of a bridge abutment. Back-analysis of this failure responds to the fundamental problem of estimating the undocumented magnitude of this extreme event. The paper estimates a lower bound value of the flow velocity at the studied location. This can be valuable input for the interpretation of the extensive damage that took place downstream and for the re-assessment of flood risk in a region where similar events are expected to become more frequent because of climate change. The approach, where disaster forensics and engineering analysis are used to fill the gap of missing real-time measurements, can be implemented for the a posteriori estimation of flood intensity in similar events. The well-documented case study of a bridge failure due to extreme flooding can also be used for validation of future numerical and experimental methods and motivate investigations of the mechanisms governing flow-soil-structure interaction in river crossings.


Assuntos
Desastres , Colapso Estrutural , Mudança Climática , Inundações , Rios
7.
Environ Sci Pollut Res Int ; 29(28): 43072-43088, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35091935

RESUMO

The present study investigated metal and metalloid dynamics in the estuarine water of the Doce River (Brazil) after the collapse of an iron ore-processing tailing dam in 2015. Spectroscopic and isotopic techniques were applied to bring new insights into the effects of the dam failure on the dynamics and hazardousness of particulate and dissolved metal(loid) concentrations along the fluvial-estuarine continuum. Spectroscopic analysis showed that the suspended particulate matter (SPM) of the Doce River estuary consisted of a combination of soil-delivered particles and fine tailing mud particles with small amounts of coarse tailing mud Fe oxides (~150-µm width). Enrichment and contamination factors showed that the dam failure increased particulate Fe, Pb, Cd, and As, and dissolved Pb concentrations. Total concentrations of As (15 µg/L), Pb (30 µg/L), Cd (8 µg/L), and Cr (105 µg/L) increased up to values higher than quality and regulatory guidelines. Human health risk assessment showed that local communities are exposed to a potentially chronic Cr noncarcinogenic effects, although Cr high concentrations were not linked with the dam failure by this study. The particulate Pb isotope signatures reported herein (206/207Pb ratios of 1.214 ± 0.006 and 208/206Pb ratios of 2.025 ± 0.011) can be applied to constrain metal(loid) sources in the Doce River sediment plume and continental shelf. The river-ocean mixing zone caused abrupt changes metal(loid) partitioning (Zn, Pb, Cr, Cu, Cd, and As), controlling their fate in the estuary and the Brazilian southeast coastal.


Assuntos
Metais Pesados , Colapso Estrutural , Poluentes Químicos da Água , Brasil , Cádmio/análise , Monitoramento Ambiental/métodos , Estuários , Humanos , Ferro/análise , Chumbo/análise , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise
8.
Disaster Med Public Health Prep ; 16(4): 1341-1345, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34176545

RESUMO

OBJECTIVE: The objective of this study was to determine whether coordination of prehospital emergency health services and Disaster and Emergency Management Presidency (DEMP) and being prepared for disasters, such as building collapses, allow quick evaluation and fast intervention. METHODS: The information flow, hierarchy, treatment, and rehabilitation processes, and rescue organization and planning during the rescue attempt for 35 people who needed help due to this building collapse were reviewed. RESULTS: Of the 43 people who lived in this 8-story building, 35 were inside the building during the collapse; 40% of them were assessed as injured and 60% as exitus. Almost two-thirds (64.3%) of the injured individuals who were rescued were women. The mean duration until rescue was 330 (57.0-512.0) min. CONCLUSIONS: Leading and important factors that can increase the success rate in search and rescue interventions are informing official authorities as first early warning by individuals who can clearly define the situation, early security measures by security forces arriving before the health and search-rescue teams, accurate identification of estimated numbers of injured victims, and identifying and informing appropriate hospitals which victims rescued from the debris will be transferred to there.


Assuntos
Planejamento em Desastres , Desastres , Serviços Médicos de Emergência , Colapso Estrutural , Feminino , Humanos , Masculino
9.
Sci Total Environ ; 807(Pt 2): 150880, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34634342

RESUMO

In November 2015, the collapse of the Fundão dam (Minas Gerais, Brazil) carried over 40 × 106 m3 of iron ore tailings into the Doce river and caused massive environmental and socioeconomic impacts across the watershed. The downstream mudslide scavenged contaminants deposited in the riverbed, and several potentially toxic elements were further released through reduction and solubilization of Fe oxy-hydroxides under estuarine conditions. A turbidity plume was formed off the river mouth, but the detection of contaminants' dispersion in the ocean remains poorly assessed. This situation is specially concerning because Southwestern Atlantic's largest and richest reefs are located 70-250 km to the north of the Doce river mouth, and the legal dispute over the extent of monitoring, compensation and restoration measures are based either on indirect evidence from modeling or on direct evidence from remote sensing and contaminated organisms. Coral skeletons can incorporate trace elements and are considered good monitors of marine pollution, including inputs from open cut mining. Here, we studied a Montastraea cavernosa (Linnaeus 1767) coral colony collected 220 km northward to the river mouth, using X-rays for assessing growth bands and Laser Ablation Inductively Coupled Plasma Mass Spectrometry to recover trace elements incorporated in growth bands formed between 2014 and 2018. A threefold positive Fe anomaly was identified in early 2016, associated with negative anomalies in several elements. Variation in Ba and Y was coherent with the region's sedimentation dynamics, but also increased after 2016, akin to Pb, V and Zn. Coral growth rates decreased after the disaster. Besides validating M. cavernosa as a reliable archive of ocean chemistry, our results evidence wide-reaching sub-lethal coral contamination in the Abrolhos reefs, as well as different incorporation mechanisms into corals' skeletons.


Assuntos
Antozoários , Colapso Estrutural , Oligoelementos , Animais , Monitoramento Ambiental , Rios
10.
Sci Total Environ ; 816: 151660, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-34785229

RESUMO

Sequences of erosion control/consolidation check dams are the most widespread channel countermeasure in the European Alps. Some of them were built in the past based on ancient technologies. Nowadays they may not be fully adequate to mitigate the debris-flow/flood events that are becoming more frequent and intense. Consequently, there is the remote possibility that they could fail with disastrous consequences as observed in some cases. A reliable methodology to reproduce the effect of check dam collapse has not yet proposed. Therefore the aim of this study is to define a procedure to simulate the effect of check dam collapse in a debris-flow event. In this study we analysed the catastrophic debris flow occurred in the Rotian channel (Italian Alps) during which a series of check dams collapsed magnifying the event and causing severe damages. With the aid of field data we reconstructed the event and used the simulation tool r.avaflow to reproduce the debris flow. We then defined three scenarios to simulate the event: (A) debris-flow propagation over an erodible channel; (B) propagation on a rigid channel bed combined with the release of impulsive masses to isolate the analysis of the effect of check dam collapse; (C) a combination of the previous scenarios. The simulation performance was assessed analysing the pre- and post-event LiDAR surveys. Results showed that the C scenario accurately reproduced the observed debris-flow erosion pattern. In particular, we found out that most of the entrained debris volume derived from bed erosion rather than the sediment retained by check dams. The adopted method, which composes the contribution of bed erosion and check dam collapse, could be of particular relevance for residual risk estimation when mitigation structures are old and may fail with potential disastrous consequences.


Assuntos
Desastres , Colapso Estrutural , Itália
11.
Sci Total Environ ; 807(Pt 2): 151486, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34742806

RESUMO

Human-induced rapid environmental changes can disrupt habitat quality in the short term. A decrease in quality of habitats associated with preference for these over other available higher quality is referred as ecological trap. In 2015, the Fundão dam containing iron mining tailings, eastern Brazil, collapsed and released about 50 million cubic meters of metal-rich mud composed by Fe, As, Cd, Hg, Pb in three rivers and the adjacent continental shelf. The area is a foraging site for dozens of seabird and shorebird species. In this study, we used a dataset from before and after Fundão dam collapse containing information on at-sea distribution during foraging activities (biologging), dietary aspects (stable isotopes), and trace elements concentration in feathers and blood from three seabird species known to use the area as foraging site: Phaethon aethereus, Sula leucogaster, and Pterodroma arminjoniana. In general, a substantial change in foraging strategies was not detected, as seabirds remain using areas and food resources similar to those used before the dam collapse. However, concentration of non-essential elements increased (e.g., Cd and As) while essential elements decreased (e.g., Mn and Zn), suggesting that the prey are contaminated by trace elements from tailings. This scenario represents evidence of an ecological trap as seabirds did not change habitat use, even though it had its quality reduced by contamination. The sinking-resuspension dynamics of tailings deposited on the continental shelf can temporally increase seabird exposure to contaminants, which can promote deleterious effects on populations using the region as foraging sites in medium and long terms.


Assuntos
Colapso Estrutural , Animais , Aves , Brasil , Ecossistema , Humanos , Rios
12.
Sci Total Environ ; 807(Pt 2): 151231, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34715230

RESUMO

The Abrolhos bank is home of the richest coral reef system of the Southwestern Atlantic, where endemic coral species are found. It has been reported that Abrolhos' corals are under intense stress due to increasing of Marine Heat Waves during the last decades. Additionally, anthropic interventions along the adjacent coastal regions are a factor of concern since they contribute to the increase in the sediment load and to organic debris input in the reef domain. In November 2015, the collapse of the Fundão mining tailings dam resulted in the release of approximately 50 million m3 of iron oxide and quartz-rich slurry into the Doce River. Aiming at using a fingerprint of the tailings and to assess the presence of traces of the Fundão dam material from this event on the Abrolhos bank, this work presents new 87Sr/86Sr and 143Nd/144Nd isotope ratios of marine suspended sediment samples collected between 2016 and 2020 from a network of sediment traps throughout the reef and complementary suspended material at sea. In parallel, we monitored meteo-oceanographic parameters and modeled surface marine currents as an attempt to identify the sediment transport between the Doce River mouth and Abrolhos bank. The r isotopes were used as provenance proxies based on the fact that minerals and rocks tend to have specific isotopic signatures reflecting their own geological derivation. In this context, the isotopic ratios of various potential regional sources for the sedimentation in Abrolhos bank were evaluated. Our monitoring and isotopic measurements indicate that Doce River signatures are detected at Abrolhos bank, following the seasonal Doce River discharge at sea. Isotopic signature of Doce River at Abrolhos bank was also observed during the austral winter (July-August) when cold fronts migrate at the Brazilian coast with higher frequency and energy.


Assuntos
Antozoários , Colapso Estrutural , Animais , Brasil , Recifes de Corais , Sedimentos Geológicos , Isótopos
13.
Front Public Health ; 10: 1104534, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36699904

RESUMO

In June 2021, a condominium in Florida collapsed, with the loss of 98 lives. Search and rescue teams spent 2 weeks, recovering the victims. This study's objective was to assess the presence of psychological symptoms that might emerge in the following months, using the PTSD Checklist for DSM-5 (PCL-5), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder - 7 (GAD-7), Suicide Cognitions Scale-Short (SCS-S), and the Insomnia Severity Index (ISI). A monthly survey conducted for 3 months found that overall, mean scores on these measures did not indicate significant emotional distress. We then compared the scores when the group was divided into responders who recovered human remains and those who did not. Scores were significantly higher among the subgroup that recovered human remains. Fifty-three percent (53%) of this sub-group met the cut-off score for a provisional diagnosis of PTSD, depressive disorder or generalized anxiety disorder-15% met the cut-off score criteria on the PCL-5 for probable PTSD, 36.8% for probable depressive disorder on the PHQ-9, and 26.3% for probable generalized anxiety disorder on the GAD-7. The results are consistent with other investigations examining mental health after mass disasters. Specifically, not all first responders will develop emotional distress but certain recovery activities may put some responders at higher risk, with a percentage displaying psychological distress. The results emphasize the need to assess the impact of these events on the mental health of first responders and to consider strategies to prevent or mitigate the development of impairing psychopathology.


Assuntos
Desastres , Transtornos de Estresse Pós-Traumáticos , Colapso Estrutural , Humanos , Restos Mortais , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Ansiedade/diagnóstico
14.
PLoS One ; 16(8): e0256028, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34383815

RESUMO

China is shifting from the stage of large-scale bridge construction to the stage of equal emphasis on the construction and maintenance of bridges. The problems of low efficiency and high cost in bridge inspection are becoming more and more prominent, which threaten people's life safety. In this paper, the deterioration state prediction model of concrete beam bridge under Boosting DT C5.0 was established as the basis, and optimization suggestions were put forward in terms of bridge inspection standards and processes, which aims to perfect the bridge inspection mechanism, realize the fine management of the bridge and prolong the service life of the bridge. Research shows that: first, the bridge inspection standard with a single index should be improved into the bridge inspection standard with multiple indexes, so as to scientifically determine the bridges that need to be inspected and optimize the allocation of maintenance resources. Second, the bridge deterioration state prediction model is used to add a screening mechanism for the bridge in the inspection plan, which can effectively reduce the workload of bridge inspection and enhance the inspection efficiency. Third, the deterioration phenomenon of coexistence between adjacent traffic assets should be fully considered and the linkage inspection mechanism of adjacent traffic assets should be established to improve the effect of bridge inspection.


Assuntos
Algoritmos , Materiais de Construção/análise , Teste de Materiais/normas , Estresse Mecânico , Colapso Estrutural/prevenção & controle , Humanos , Fenômenos Mecânicos , Vibração
15.
Sci Total Environ ; 800: 149302, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34426300

RESUMO

The ecology and life history of marine megafauna can answer the ecological importance of a region. This study assesses and monitors the abundance and home range of sea turtles, seabirds, marine mammals and the association with coastal microhabitats in potentially impacted areas at the Rio Doce river mouth, Comboios, and Piraquê-açu river mouth after the collapse of the Fundão dam. Remotely Operated Vehicles (ROV) and UAVs (Unmanned Aerial Vehicles, or drones) were used for megafauna species identification, behavior, population data, habitat characterization, and monitoring of environmental protection areas. The species Sotalia guianensis and Pontoporia blainvillei were the most recorded cetaceans, and the main observed behavior was feeding. Guiana dolphin (S. guianensis) occurs in greater density in the Rio Doce river mouth region, resulting in more than 10 sightings/km2, while franciscana (P. blainvillei) were the most concentrated Comboios area. The seabirds (all species) had up to 15 sightings/km2 at the Rio Doce river mouth, the highest density among sampled areas. The green turtle (Chelonia mydas) was the most frequently recorded, followed by the leatherback turtle (Dermochelys coriacea). The green turtle occurred at a higher concentration at the Piraquê-Açu river mouth (above 6 sightings/km2). The sites closest to Rio Doce river mouth and Comboios predominantly showed mud bottoms, while those at Piraquê-Açu mouth were mostly reef structures. The estuarine areas showed greater importance for megafauna than marine areas.


Assuntos
Golfinhos , Colapso Estrutural , Tartarugas , Poluentes Químicos da Água , Animais , Brasil , Ecossistema , Monitoramento Ambiental , Rios , Poluentes Químicos da Água/análise
16.
Sci Total Environ ; 796: 148965, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34328909

RESUMO

Freshwater biodiversity has been impacted by several stressors such as eutrophication, turbidity and metals. Besides these frequent impacts, large-scale accidents occasionally affect aquatic systems, input an intense load of contaminants to the water bodies, as in the case of the Fundão tailing dam collapse (Brazil), which launched millions of meters cubic of iron ore tailing in the Doce River Basin. Our aim in this study was to assess how much stress the environmental conditions of lentic and lotic environments in the lower region of this basin impact the periphytic community. In addition, we intend to verify whether the limits of changes of the periphytic communities agreed with Brazilian legislation for the protection of aquatic life. For that, monthly samplings were carried out in seven sampling stations in lentic environments and five in lotic environments, including the Doce River channel, between October/2018 and March/2021 (except in October/2019). Concentrations of metals (iron, aluminum, manganese and chromium), total nitrogen, total phosphorus, conductivity, and suspended particulate material were determined. The periphytic community was collected from natural substrates (macrophytes or pebbles) and quantified by the sedimentation chamber method. From these data, thresholds of concentrations of variables that caused changes in periphytic communities were determined by the Threshold Indicator Taxa ANalysis (TITAN). We concluded that evidence of chronic impact of iron ore tailing should be revealed and that the standards established by Brazilian legislation may be incompatible with the protection of aquatic life. Moreover, we found that the Doce River mouth and surrounding environments were the most stressful environments for the periphytic communities.


Assuntos
Colapso Estrutural , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Rios , Poluentes Químicos da Água/análise
17.
An Acad Bras Cienc ; 93(1): e20201209, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33886703

RESUMO

The restoration methods applied on the areas affected by the Fundão tailings dam collapse have a high priority in Mariana region. We evaluated the effect of different restoration methods and site preparation techniques, depth and seasonality on penetration resistance of tailings, and how these predictors affect tree aboveground biomass in areas affected by the Fundão dam collapse in Mariana, Brazil. No significant differences in penetration resistance and aboveground biomass between treatments were observed, but significant differences were observed between seasonal periods. The main univariate model explained the significant effects of depth and seasonality, mainly by a negatively wet effect on penetration resistance. According to the best models (univariate and multivariate) were those that had depth as a predictor. This study showed how penetration resistance can be an indicator to select the best period for restoration process in areas affected by the collapse of the Fundão dam, but no limit to the aboveground biomass recovery on tailing.


Assuntos
Mineração , Colapso Estrutural , Biomassa , Brasil , Monitoramento Ambiental , Florestas
18.
Leg Med (Tokyo) ; 50: 101870, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33730619

RESUMO

We aimed to show the usefulness of odontological assessment in forensic investigation. Charred remains of two female siblings were found in a collapsed building after a gas explosion. Due to thermal damage of the bodies, the facial characteristics, fingerprints, height and weight could not be used to distinguish between siblings. Since the victims, 4 and 10-year-old, died simultaneously and all personal belongings were lost, DNA profiling performed with their parents only confirmed the relationship. As dental charts of siblings were not found, we could not easily discriminate which remains would be of the elder and which of the younger sister. The odontological examination enabled us to discriminate between the siblings based on differences in deciduous and permanent dentition. We conclude that although DNA profiling is becoming a standard method of personal identification in some cases it should be supported by additional methods to deliver comprehensive forensic reports.


Assuntos
Impressões Digitais de DNA , Explosões , Colapso Estrutural , Criança , Pré-Escolar , Feminino , Odontologia Legal , Humanos , Irmãos
19.
Chemosphere ; 262: 127879, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32781334

RESUMO

The collapse of the Fundão Dam, in Southeastern Brazil, caused about 50 million m³ of iron ore tailings to sluice down the mountain to Rio Doce, in what is considered the greatest environmental disaster in Brazilian history. The fluvial system received an intense and sudden mudflow that was transported for more than 650 km, before reaching the Atlantic Ocean. Because the area was already impacted by the mineral activities in the region, it becomes essential to evaluate the environmental conditions before the disaster to correctly assess the disaster real damage. This study compares the concentration of trace metals in the sediments of the Rio Doce alluvial plain, before and after the dam collapse, as well as the newly deposited iron ore tailings that became part of the sedimentary framework. The data indicate that the fine particles deposited have since been incorporated into the sandy river sediments. The cadmium and arsenic contents in the sediments increased to levels above the National Environment Council thresholds. The comparison between the levels of trace metals in the situations before and after disaster shows that the mining mud is the source of cadmium while the arsenic was present before the environmental disaster, and its concentration increased due to sediment remobilization. The iron ore tailings deposited on the alluvial sediments also affected the physical parameters since the formed ferruginous crusts waterproofed the ground surface and may, gradually, release toxic metals when exposed to weathering and river reworking.


Assuntos
Monitoramento Ambiental , Metais/análise , Mineração , Poluentes Químicos da Água/análise , Oceano Atlântico , Brasil , Desastres , Ferro , Compostos de Ferro , Minerais , Rios , Colapso Estrutural , Oligoelementos
20.
Environ Int ; 146: 106284, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33264733

RESUMO

Manganese (Mn) is an abundant element in terrestrial and coastal ecosystems and an essential micronutrient in the metabolic processes of plants and animals. Mn is generally not considered a potentially toxic element due to its low content in both soil and water. However, in coastal ecosystems, the Mn dynamic (commonly associated with the Fe cycle) is mostly controlled by redox processes. Here, we assessed the potential contamination of the Rio Doce estuary (SE Brazil) by Mn after the world's largest mine tailings dam collapse, potentially resulting in chronic exposure to local wildlife and humans. Estuarine soils, water, and fish were collected and analyzed seven days after the arrival of the tailings in 2015 and again two years after the dam collapse in 2017. Using a suite of solid-phase analyses including X-ray absorption spectroscopy and sequential extractions, our results indicated that a large quantity of MnII arrived in the estuary in 2015 bound to Fe oxyhydroxides. Over time, dissolved Mn and Fe were released from soils when FeIII oxyhydroxides underwent reductive dissolution. Due to seasonal redox oscillations, both Fe and Mn were then re-oxidized to FeIII, MnIII, and MnIV and re-precipitated as poorly crystalline Fe oxyhydroxides and poorly crystalline Mn oxides. In 2017, redox conditions (Eh: -47 ± 83 mV; pH: 6.7 ± 0.5) favorable to both Fe and Mn reduction led to an increase (~880%) of dissolved Mn (average for 2015: 66 ± 130 µg L-1; 2017: 582 ± 626 µg L-1) in water and a decrease (~75%, 2015: 547 ± 498 mg kg-1; 2017: 135 ± 80 mg kg-1) in the total Mn content in soils. The crystalline Fe oxyhydroxides content significantly decreased while the fraction of poorly ordered Fe oxides increased in the soils limiting the role of Fe in Mn retention. The high concentration of dissolved Mn found within the estuary two years after the arrival of mine tailings indicates a possible chronic contamination scenario, which is supported by the high levels of Mn in two species of fish living in the estuary. Our work suggests a high risk to estuarine biota and human health due to the rapid Fe and Mn biogeochemical dynamic within the impacted estuary.


Assuntos
Manganês , Colapso Estrutural , Animais , Brasil , Ecossistema , Compostos Férricos , Humanos , Oxirredução , Solo
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