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1.
Environ Monit Assess ; 195(2): 337, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36705892

RESUMO

At the end of 2015, the Fundão dam belonging to the Samarco S.A. mining company was ruptured, releasing a flood of mud into the Gualaxo do Norte River, which advanced into the Doce River. The aim of the present study was to apply exploratory multivariate approaches to water quality data obtained during sampling campaigns at the Gualaxo do Norte River during the dry and rainy seasons, between July 2016 and June 2017. A total of 27 locations along the river were sampled, covering unaffected areas and regions influenced by the tailings waste from the dam. Determinations of chemical, physical, and microbiological water quality parameters were performed. Application of principal component analysis (PCA) resulted in the first two components together explaining 39.49% and 37.91% of the total variance for the dry and rainy season data, respectively. In both cases, the PCA groups were related to variables such as turbidity and total solids, which both presented higher values in regions affected by the mud flow. These results are in agreement with those obtained by the Kohonen neural network method, where two-dimensional maps confirmed the samples according to the affected and unaffected area by the disaster.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , Rios , Monitoramento Ambiental , Brasil , Poluentes Químicos da Água/análise
2.
Arch Virol ; 165(3): 715-718, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31873766

RESUMO

In the present study, we evaluated the degree of contamination of fresh vegetables, cheeses and jellies from disaster area in Brazil with bacteria and enteric viruses. Food samples (n = 350) were tested for Escherichia coli, Salmonella spp., Listeria monocytogenes, Staphylococcus spp., and enteric viruses (rotavirus A (RVA), human adenovirus (HAdV), hepatitis A virus (HAV), and human norovirus (HNoV). E. coli was present in 56% of the samples, Salmonella spp. was present in 14% of the samples, L. monocytogenes and Staphylococcus spp. (coagulase-positive) were present in 36% of the samples. The enteric viruses RVA and HAdV were detected in cheeses and vegetables.


Assuntos
Queijo/microbiologia , Contaminação de Alimentos/análise , Verduras/microbiologia , Adenovírus Humanos/isolamento & purificação , Brasil , Escherichia coli/isolamento & purificação , Fazendas , Vírus da Hepatite A/isolamento & purificação , Humanos , Listeria monocytogenes/isolamento & purificação , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação
3.
Arch Environ Contam Toxicol ; 77(1): 144-153, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30976887

RESUMO

The 2015 rupture of the Fundão dam near the district of Bento Rodrigues in Mariana, Minas Gerais, Brazil, released around 50 million m3 of iron ore tailings. The first tributary of the Rio Doceto receive this waste was the Gualaxo do Norte River. Many groups in Brazil and from around the world have studied the environmental and social impacts of this disaster. However, relationships between the introduction of mining waste, the geological complexity of the area, and the presence of pathogenic organisms have not yet been investigated. The present study aimed to measure the concentrations of enteric pathogens along the Gualaxo do Norte River after the environmental disaster and to correlate their abundance with the presence of metals and semimetals coming from both mining tailings and geological sources. For this purpose, we collected water samples from 27 stations along the entire basin during a hydrological year. The concentrations of metals and semimetals measured in this study were generally within limits established by national and international legislation, except for those of iron and manganese. Positive correlations between the human adenovirus (HAdV) and arsenic, barium, iron, lead, manganese, and nickel were confirmed, allowing us to observe that there is an abundance of the potentially infectious virus present in the studied sites containing metal/semimetal concentrations. These studies indicate the importance of investigations that consider viral enteric pathogens complexed with metals and may favor the stability and prolongation of the infectivity of such pathogens in water destined for human and animal usage.


Assuntos
Adenovírus Humanos/isolamento & purificação , Metais/análise , Rios/química , Rios/virologia , Poluentes Químicos da Água/análise , Brasil , Monitoramento Ambiental , Humanos , Mineração
4.
Environ Sci Pollut Res Int ; 28(36): 50593-50601, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33963994

RESUMO

The hydraulic characteristics of the Gualaxo do Norte River (RGN), a tributary of the upper Rio Doce basin, were affected in November 2015 by the rupture of the iron ore tailings dam at Fundão, in Bento Rodrigues, Mariana, Minas Gerais. We analyzed two sections of the RGN, located upstream and downstream of the Fundão dam. Measurements were taken at 11 stations along the main river in distinct seasonal periods, including river depth, river width, velocity, and flow. We also calculated the deoxygenation coefficient (K1) and the reaeration coefficient (K2) and collected elaborate bathymetric profiles of the sections. Anthropogenic interference influenced the river's hydraulic characteristics mainly in relation to the depth. In upstream sections, the changes are believed to be due to mining activities at the head of the river, while downstream effects were due to the introduction of iron ore tailings coming from the rupture of the Fundão dam. Despite these influences, deoxygenation coefficient values were typical for clean water, and the reaeration coefficient findings show that the RGN is efficient at biological degradation of the organic matter even receiving untreated domestic sewage from riparian communities. With the results obtained in this work, we seek to replicate a source of information about the current state of the region and to contribute information to future river planning, control, and restoration projects.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Brasil , Mineração , Rios , Água , Poluentes Químicos da Água/análise
5.
Environ Sci Pollut Res Int ; 27(4): 4365-4375, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31832945

RESUMO

The rupture of the Fundão dam released about 39 million m3 of tailings into the Rio Doce/Brazil. The sediment load increase in the affected rivers has become a concern. As such, this article provides recent information about the region. In addition, based on past studies in the region, it shows the magnitude and dynamics of the environmental impacts caused by the rupture of the dam on the bottom sediments. Sediment samples in different seasonal periods were collected at eleven sampling stations located along the Gualaxo do Norte River, the first tributary of the Rio Doce affected by the environmental disaster. These sediments underwent physical, chemical, and granulometric analyses for their organic, metal, and semimetal content. The contamination factor and the enrichment factor of the samples also were calculated. To evaluate the anthropogenic contributions to sediment metal concentrations, reference values (regional background values) for the Gualaxo do Norte River were used. The results indicate that, in the sampling stations not affected by the disaster, the concentrations of the metals and semimetals reflect the geology of the Quadrilátero Ferrífero. However, in the area affected by the environmental disaster, there were changes in the chemical and physical properties of the bottom sediment, mainly in the concentrations of iron, organic matter, and fine sediment fractions. This was reflected in the contamination factors and enrichment factors calculated for the sediments of the sampling stations. Iron and manganese concentrations in sediments are much higher than other rivers in the world that are unaffected by mining activities. The observed changes in the bottom sediments of the river suggest a need for constant monitoring of the iron because the iron oxide minerals present in silt and clay have a high adsorption capacity. In the long term, these factors may contribute to the decrease of the quality of these sediments and consequently of the waters and biota present in these environments.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Mineração , Rios , Poluentes Químicos da Água/química , Brasil
6.
Food Environ Virol ; 11(2): 178-183, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30747345

RESUMO

Although the effects of heavy metals on the behavior, including infectivity, of bacteria have been studied, little information is available about their effects on enteric viruses. We report an investigation of effects on the biosynthesis of human adenoviruses (HAdV) and hepatitis A (HAV) of waters contaminated with mineral waste following an environmental disaster in Mariana City, Minas Gerais State, Brazil. The study area was affected on November 5, 2015, by 60 million m3 of mud (containing very high concentrations of iron salts) from a mining reservoir (Fundão), reaching the Gualaxo do Norte River (sites evaluated in this study), the "Rio Doce" River and finally the Atlantic Ocean. We found substantial counts of infectious HAdV and HAV (by qPCR) in all sampled sites from Gualaxo do Norte River, indicating poor basic sanitation in this area. The effects of iron on viral infection processes were evaluated using HAdV-2 and HAV-175, as DNA and RNA enteric virus models, respectively, propagated in the laboratory and exposed to this contaminated water. Experiments in field and laboratory scales found that the numbers of plaque forming units (PFU) of HAdV and HAV were significantly higher in contaminated water with high iron concentrations than in waters with low iron concentration (< 20 µg/L of iron). These findings indicate that iron can potentiate enteric virus infectivity, posing a potential risk to human and animal health, particularly during pollution disasters such as that described here in Mariana, Brazil.


Assuntos
Adenovírus Humanos/crescimento & desenvolvimento , Vírus da Hepatite A/crescimento & desenvolvimento , Ferro/análise , Minerais/análise , Rios/virologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , Adenovírus Humanos/metabolismo , Brasil , Enterovirus/genética , Enterovirus/crescimento & desenvolvimento , Enterovirus/isolamento & purificação , Enterovirus/metabolismo , Monitoramento Ambiental , Hepatite A/virologia , Vírus da Hepatite A/genética , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite A/metabolismo , Humanos , Ferro/metabolismo , Mineração , Rios/química , Poluição da Água
7.
Environ Pollut ; 252(Pt A): 8-13, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146241

RESUMO

The present study evaluated the river water quality improvement by implementation of household-based biodigesters in vulnerability and poverty rural area, in Minas Gerais State-Brazil. For that, 78 household-based biodigesters were installed for domestic wastewater treatment. Wastewater was collected before and after treatment and the physicochemical parameters and pathogens removal (human adenovirus (HAdV), hepatitis A (HAV) virus, Salmonella sp. and Escherichia coli) were evaluated; Additionally, river water was sampled before and after the household-based biodigesters implementation, to verify the contamination reduction and the positive impact of domestic wastewater treatment on waterborne pathogen reduction, considering HAdV, HAV, Salmonella sp. and E. coli quantification. The applicability in real-scale of decentralized treatment systems using household-based biodigesters promoted reduction of 90, 99, 99.99 and 99.999% from HAV, Salmonella sp., E. coli and HAdV from domestic wastewater, respectively; The river water quality improvement before the wastewater treatment application was highlight in the present study, considering that the reduction of waterborne pathogens in this water in 90, 99.99 and 99.999% of E. coli, HAV and HAdV, respectively (Salmonella sp. was not detected in river water). In general, this is an important study for encouraging the decentralized sanitation in vulnerable and poverty area, as well in rural sites, considering the positive impact of this implementation on public health.


Assuntos
Adenovírus Humanos/isolamento & purificação , Escherichia coli/isolamento & purificação , Vírus da Hepatite A/isolamento & purificação , Salmonella/isolamento & purificação , Águas Residuárias/microbiologia , Purificação da Água/métodos , Biodegradação Ambiental , Brasil , Humanos , Pobreza , Áreas de Pobreza , Rios/microbiologia , População Rural , Saneamento
8.
Environ Sci Pollut Res Int ; 24(8): 7456-7467, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28110455

RESUMO

In developing countries, it is uncommon to find watersheds that have been the object of detailed environmental studies. It makes the assessment of the magnitude of environmental impacts and pollution of these sites difficult. This research demonstrated ways to understand the dynamics of river bottom sediments contamination, even for watersheds with a lack of environmental data. Based on geochemical affinity, we conducted a comprehensive study on the concentration of metals and metalloids. Then, we discussed the probable origin of the concentration of these elements at the bottom sediment along the Matipó River. The Matipó River is an important tributary of the Doce River, which stood out in international headlines because of the mining tailing dam disaster in Mariana, Minas Gerais, in 2015. The bottom sediment samples were taken in 25 stations located along the basin in different seasonal periods. The results showed that copper ([Formula: see text] = 464.7 mg kg-1) and zinc ([Formula: see text] = 287.7 mg kg-1) probably have natural origin, despite of the high concentrations. Lead ([Formula: see text] = 28.0 mg kg-1), chromium ([Formula: see text] = 153.2 mg kg-1), and nickel ([Formula: see text] = 41.8 mg kg-1) also had high concentrations at some collecting stations, and this probably reflected the local natural conditions. The bedrock of the studying basin is dominantly composed of metabasalts and metatonalites interlayered with calcitic and dolomitic metalimestone. On the other hand, the concentration was worrisome in stations near human activities, possibly due to impacts caused by unsustainably agriculture and livestock.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Metaloides/análise , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Agricultura , Brasil
9.
Eng. sanit. ambient ; Eng. sanit. ambient;23(4): 767-778, jul.-ago. 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-953285

RESUMO

RESUMO O presente estudo foi realizado na bacia hidrográfica do Rio do Peixe, Quadrilátero Ferrífero (QF), em Minas Gerais. Essa bacia apresenta um cenário geológico distinto e atividades antrópicas diversificadas, como a mineração de ferro, ouro e gemas, a agropecuária e a silvicultura. O principal objetivo desta pesquisa foi investigar as possíveis fontes de contribuições antropogênicas dos metais em sedimentos de fundo. Para isso, foram realizadas duas campanhas com amostragens de sedimentos de fundo em 12 pontos da bacia, nos meses de março e julho de 2015. A partir da técnica analítica de espectrometria de emissão óptica com plasma, foram detectadas concentrações de Al, Ca, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti e Zn nos sedimentos de fundo. Os resultados dos indicadores da qualidade dos sedimentos fator de contaminação (FC), fator de enriquecimento (FE) e índice de geoacumulação (IGEO) demonstraram que há interferências antrópicas, sendo as atividades minerárias e industriais, o despejo de efluentes domésticos e o uso e a ocupação do solo inapropriado apontados como as principais fontes de contaminação de metais da bacia.


ABSTRACT The present study was carried out in the river basin area of Rio do Peixe, Iron Quadrangle, in Minas Gerais, Brazil. This basin presents geological scenario and diversified anthropic activities, such as iron, gold and gems mining, agriculture, and forestry. The main objective of this research was to investigate the possible sources of anthropogenic contributions of metals in bottom sediments. Thus, two surveys were carried out on bottom sediments at twelve basin sites from March to July of 2015. Based on the plasma optical emission spectrometry analytical technique, we found concentrations of Al, Ca, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti and Zn in the bottom sediments. The results of the FC, FE and IGEO sediment quality indicators showed that there are anthropic interferences, in which mining and industrial activities, disposal of domestic effluents and use and occupation of inappropriate soil are identified as the main sources of metals contamination of the basin.

10.
São Paulo; Rede Nacional Feminista de Saúde e Direitos Reprodutivos; 2000. 12 p. ilus.
Monografia em Português | Coleciona SUS | ID: biblio-935312
11.
São Paulo; Rede Nacional Feminista de Saúde e Direitos Reprodutivos; 2000. 12 p. ilus.
Monografia em Português | LILACS | ID: lil-583222
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