Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Braz. j. biol ; 83: 1-10, 2023. map, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468945

RESUMO

Estuaries receive daily inputs of chemical elements which can impact the quality of water and sediment, as well as the health of biota. In addition to the sediment, bivalve mollusks have been used in the chemical monitoring of these systems. This study investigated the presence and contents of As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in superficial sediment and in bivalves (Crassostrea gasar, C. rhizophorae and Mytella guyanensis) from estuaries in the south / extreme south of Bahia State, northeast Brazil. The samples were evaluated with inductively coupled plasma optical emission spectrometry (ICP-OES, Varian 710). Except for Cd, all other elements were found in the samples, being that Co was exclusive in the sediment. The estuaries equivalent to sampling stations #1 - Valença, #2 - Taperoá, #3 - Ilhéus and #4 - Belmonte showed levels of metals compatibles with those established by the Brazilian legislation, however, the #5 - Santa Cruz Cabrália, in addition to the presence of As, presented a high level of Pb and Cu in C. gasar, which was attributed to the impacts of nautical activities in that locality.


Estuários recebem entradas diárias de elementos químicos, que podem impactar a qualidade de água e do sedimento, assim como a saúde da biota. Além do sedimento, moluscos bivalves têm sido utilizados no monitoramento químico desses sistemas. Neste estudo investigou-se a presença e os teores de As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn no sedimento superficial e em bivalves (Crassostrea gasar, C. rhizophorae e Mytella guyanensis) de estuários do sul / extremo sul do estado da Bahia, Nordeste do Brasil. As amostras foram avaliadas por espectrometria de emissão óptica de plasma indutivamente acoplado (ICP-OES, Varian 710). Exceto Cd, todos os demais elementos foram encontrados nas amostras, sendo que Co foi exclusivo no sedimento. Os estuários equivalentes às estações amostrais #1 - Valença, #2 - Taperoá, #3 - Ilhéus e #4 - Belmonte mostraram níveis de metais compatíveis com os estabelecidos pela legislação brasileira, porém, a #5 - Santa Cruz Cabrália, além da presença de As, apresentou alto nível de Pb e de Cu em C. gasar, o que foi atribuído aos impactos por atividades náuticas nesse local.


Assuntos
Animais , Bivalves , Metais Pesados/toxicidade , Poluição de Estuários/análise , Sedimentos/análise
2.
Acta amaz ; 50(2): 159-169, abr - jun. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118438

RESUMO

Studies on provenance of minerals in Amazonian rivers focus mostly on suspended sediments, while processes that control bottom-sediment production and distribution are still little known. We determined the provenance of the bottom sediments of Green Lake, a micro-basin draining into the Tapajós River, in the eastern Brazilian Amazon. We used X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and, cathodoluminescence techniques to analyze clay, light and heavy minerals of 22 samples. The lake is L-shaped, with 5.5 m maximum depth, and predominance of mud over sand in the center. Quartz and feldspar were dominant in the light fraction, while zircon, tourmaline, kyanite, rutile, and staurolite were dominant in the heavy fraction. The clay fraction was dominated by kaolinite, with morphology and degree of crystallinity indicative of a detrital origin related to weathering. The Alter do Chão Formation (ACF) is suggested as the main source of sand sediments and heavy minerals, due to their mineralogical and percentage similarity. The provenance of kaolinite was mainly the ACF, with a minor contribution of the Amazon and Tapajós rivers. The primary origin of the heavy minerals in the ACF indicates the basement of the Amazonas Basin as source rock and this formation as a source of sediments for Green Lake through weathering and erosion processes under current tropical conditions. The presence of Aulacoseira granulata and Aulacoseira ambigua indicates the importance of current erosive processes on sediment production. (AU)


Assuntos
Sedimentos/análise , Ecossistema Amazônico , Minerais
3.
Arq. bras. med. vet. zootec. (Online) ; 72(2): 623-632, Mar./Apr. 2020. ilus, mapas, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1128493

RESUMO

O presente estudo utilizou embriões de Danio rerio expostos aos elutriatos dos sedimentos estuarinos do rio Capibaribe, dos períodos chuvoso e seco, e analisou os efeitos letais, teratogênicos, bem como a frequência cardíaca. Os testes de toxicidade com os embriões seguiram as diretrizes da OECD 236. Mediante os resultados obtidos, a frequência cardíaca e a teratogenicidade foram os efeitos mais observados nos animais quando submetidos às amostras. Entre os efeitos teratogênicos, o retardo geral no desenvolvimento dos embriões foi o mais frequente durante as análises. Tais efeitos tóxicos se modificaram entre os pontos e entre os períodos de coleta. Essa variação de toxicidade pode estar relacionada à diversidade de atividades realizadas no entorno desse estuário, a influência do regime de chuvas, marés e correntes, indicando que a análise dos efeitos subletais e da teratogenicidade em embriões de D. rerio constitui bom parâmetro para avaliações de toxicidade de amostras ambientais.(AU)


The present study used Danio rerio embryos exposed to the elutriates of the estuarine sediments of the Rio Capibaribe, from the rainy and dry periods, where the lethal effects, teratogenic and heart rate were analyzed. Embryotoxicity tests followed the guidelines of OECD 236. Based on the results obtained, heart rate and teratogenicity demonstrated higher sensitivity to the samples. Among the teratogenic effects, the general delay in embryo development was the most frequent effect during the analyzes. These toxic effects changed between the points and between the collection periods. This variation of toxicity may be related to the diversity of activities carried out around this estuary, the influence of rainfall, tides, and currents, indicating the analysis of sublethal effects and teratogenicity in the D. rerio embryos are useful parameters for toxic evaluation of environmental samples.(AU)


Assuntos
Animais , Peixe-Zebra/embriologia , Sedimentos/análise , Desenvolvimento Embrionário , Frequência Cardíaca , Testes de Toxicidade , Estuários , Teratogênese
4.
Arq. ciências saúde UNIPAR ; 23(2): 107-112, maio-ago. 2019.
Artigo em Português | LILACS | ID: biblio-996708

RESUMO

Este trabalho teve como objetivo quantificar os metais Cobre e Chumbo presentes na água e no sedimento do lago Aratimbó, localizado na cidade de Umuarama-PR e analisar os indicadores abióticos de temperatura e pH da água. As coletas foram feitas em triplicatas, em três pontos distintos, em dois diferentes dias, sendo o primeiro em tempo seco, anterior a chuva e outro logo após a primeira chuva. As amostras tiveram sua temperatura e pH verificado in loco e a determinação dos metais ocorreu por meio de Espectrofotometria de Absorção Atômica por chama. Os resultados de pH obtiveram valores satisfatórios em todos os pontos. Em relação à concentração de metais, na água, houve maior concentração de chumbo antes da chuva e uma concentração abaixo do limite apenas para o cobre no ponto 1. No sedimento, a concentração de ambos metais foi maior antes da chuva, exceto no ponto três, onde a concentração foi maior após a chuva. É possível que os maiores valores de concentração para os metais tenham sido superiores no período de seca em virtude do volume aumentado de água após a chuva, com maior diluição. Assim, podendo atribuir a contaminação às atividades antropogênicas, uma vez que o lago se localiza em região urbana central.


The purpose of this paper was to quantify the copper and lead present in the water and sediments of the Aratimbó lake, located in the city of Umuarama, in the state of Paraná, and to analyze the abiotic indicators of temperature and pH of the water. The samples were taken in triplicate at three different points, on two different days - the first during dry weather, before the rain, and the other after the first rain. The temperature and pH of the samples were verified in locu and the metals were determined through Atomic Absorption Spectrophotometry by flame. The pH results obtained satisfactory values ​​at all points. Regarding the concentration of metals in the water, a higher concentration of lead was observed before the rain and a concentration below the limit was observed only for copper in point 1. In the sediment, the concentration of both metals was higher before the rain, except in point three, where the concentration was also higher after the rain. It is possible that the highest concentration values ​​for the metals were higher in the dry period due to the increased volume of water after rainfall, with higher dilution of the metals, as well as the attribution of contamination to the anthropogenic activities, since the lake is located in a central urban region.


Assuntos
Poluição da Água/análise , Cobre/toxicidade , Chumbo/toxicidade , Chuva , Temperatura , Sedimentos/análise , Rios , Metais/toxicidade
5.
Rev. biol. trop ; 66(3): 1065-1077, jul.-sep. 2018. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-977367

RESUMO

Abstract Barra de Navidad lagoon (BNL) is one of the main coastal wetlands in the coast of the State of Jalisco, Mexico. It is a Ramsar site (wetland of international importance) and has been included among the 81 mangrove sites with biological relevance and ecological rehabilitation needs in Mexico. Although fish fauna composition is well known in BNL, little evidence exists that support seasonal and spatial changes of fish assemblages' structure. The hypothesis tested in this study was that there are significant seasonal and spatial changes in BNL fish assemblages' composition which can be explained, at least partially, by changes in salinity, water temperature and sediment's granulometry. Fish assemblages were sampled monthly from October 2012 to September 2013 at four zones of BNL, using gill nets (7.62 mm stretched mesh). A sample was taken every month in a randomly selected area of each zone. Prior to each sampling operation, water salinity and temperature were measured using an YSI-30 probe. Samples of sediment were collected with a Van Veen grab sampler in three randomly selected points of each zone for granulometry and organic matter analyses. A total of 2 026 individuals belonging to 48 species were collected. Slightly more than 90 % of all caught fish belonged to nine species: Peruvian mojarra (Diapterus brevirostris), Pacific crevalle-jack (Caranx caninus), White mullet (Mugil curema), Blue sea-catfish (Ariopsis guatemalensis), Oval flounder (Syacium ovale), Pacific lined sole (Achirus mazatlanus), Yellowfin mojarra (Gerres simillimus), Pacific bumper (Chloroscombrus orqueta) and Freckled porcupinefish (Diodon holocanthus). Generalized linear models yielded significant differences among zones for the mean abundance of each of these nine species, but only in two cases seasonal differences were significant (D. brevisrostris and C. caninus). Permutational multivariate analysis of variance yielded also significant differences among zones and between seasons for the composition of the fish assemblage. Redundancy analysis using salinity, temperature, and percentage mud in sediment as environmental variables showed that fish assemblage's composition varies along two main gradients defined by mud fraction of sediments in a small spatial scale (~ 3 km) and salinity in a seasonal scale. Percentage of variation explained by canonical axes was less than 25 %, indicating that other factors could be influencing changes in assemblage composition. As most species appear as juveniles in the lagoon, fluctuations in their abundances could be linked, at least partially, with recruitment events. Rev. Biol. Trop. 66(3): 1065-1077. Epub 2018 September 01.


Resumen La laguna Barra de Navidad (LBN) es uno de los principales humedales costeros en la costa del Estado de Jalisco, México. Es un sitio Ramsar (humedal de importancia internacional) y ha sido incluida entre los 81 sitios de manglar con relevancia biológica y necesidades de rehabilitación en México. Aunque la composición de la ictiofauna es bien conocida en LBN, hay poca evidencia sobre la existencia de cambios estacionales y espaciales en la estructura de la misma. La hipótesis que guió este trabajo fue que en la composición de la ictiofauna de la laguna Barra de Navidad hay cambios espaciales y estacionales que pueden ser explicados, al menos parcialmente, por cambios en la salinidad, temperatura del agua y granulometría del sedimento. Los peces fueron muestreados mensualmente de octubre 2012 a septiembre 2013 en cuatro zonas de la laguna, usando redes agalleras (7.62 mm de malla estirada). Se tomó una muestra cada mes en un área seleccionada aleatoriamente en cada zona. Previo a cada operación de muestreo, se midieron la salinidad y la temperatura del agua con una sonda YSI-30. Muestras de sedimento para análisis granulométrico y del contenido de materia orgánica, se recolectaron con una draga tipo Van Veen en tres puntos seleccionados aleatoriamente en cada zona. Se recolectaron 2 026 individuos de 48 especies de peces. Poco más de 90 % de todos los peces contados pertenecieron a nueve especies: Diapterus brevirostris, Caranx caninus, Mugil curema, Ariopsis guatemalensis, Syacium ovale, Achirus mazatlanus, Gerres simillimus, Chloroscombrus orqueta y Diodon holocanthus. Modelos lineales generalizados arrojaron diferencias significativas entre zonas para la abundancia media de estas nueve especies, pero solo en dos casos se encontraron diferencias significativas entre estaciones (D. brevirostris y C. caninus). El análisis multidimensional de varianza basado en permutaciones, arrojó también diferencias significativas entre zonas y entre estaciones para la composición de la ictiofauna. El análisis de redundancia usando la salinidad, la temperatura y el porcentaje de lodo en el sedimento como variables ambientales, mostró que la composición de la ictiofauna varía a lo largo de dos gradientes definidos por la fracción de lodo de los sedimentos en una escala espacial pequeña (~ 3 km) y la salinidad en una escala estacional. El porcentaje de variación explicado por los ejes canónicos fue menor de 25 %, indicando que otros factores pudieran influir en los cambios de la composición de la ictiofauna. Como la mayoría de las especies aparecen en su estadio juvenil en la laguna, las fluctuaciones en sus abundancias pudieran estar relacionadas, al menos parcialmente, con eventos de reclutamiento.


Assuntos
Animais , Sedimentos/análise , Sedimentos Geológicos/análise , Salinidade , Peixes , México
6.
Acta toxicol. argent ; 26(1): 1-11, mayo 2018. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-973611

RESUMO

El hombre ha cambiado el ambiente para sostener la demanda global de recursos naturales como el agua. La gestión de los cuerpos hídricos tiene que ser constante, con el propósito preventivo y correctivo, dependiendo del estado de antropización de cada sistema. El objetivo de este artículo fue analizar la toxicidad del sedimento y los metales Mn, Zn, Pb, Ni, Cd y Cu, en el reservorio Paiva Castro, que abastece la Region Metropolitana de São Paulo. Se realizaron 2 muestreos (Mayo 2011, estación seca y Enero de 2012, estación húmeda) y se analizaron 5 puntos próximos a la captación de agua por la Companhia de Saneamento Básico do Estado de São Paulo. Se realizaron ensayos de toxicidad aguda y crónica en sedimento, a través de ensayos biológicos con el cladócero Daphnia similis y el insecto Chironomus xanthus. El tratamiento de datos se realizó con el test de Fisher (mortalidad). El nivel de asociación entre las variables en sedimento y en los test ecotoxicológicos fueron evaluados por test no-paramétricos, a través del coeficiente de correlación de Spearman's. Los resultados del presente trabajo señalaron bajas concentracones de metales en el sedimento del área de estudio y ausencia de toxicidad en los organismos ensayados. Se puede concluir que área estudiada del reservorio Paiva Castro se encuentra poco impactada por los metales, sin efectos directos sobre la calidad de vida los organismos bentónicos: D. similis y C. xanthus.


Man had changed the natural environment in an attempt trying to supply the global demand for resources. The management of the hydric bodies has to be constant, with preventive and corrective purpose, depending on the eutrophization state of each one. The objective of this article was to analyze the sediment toxicity and the metals Mn, Zn, Pb, Ni, Cd and Cu, in the Paiva Castro reservoir, that supply the Metropolitan Region of São Paulo. It was made 2 collections (May 2011, dry season and January 2012, wet season). It was analyzed 5 points next to the water captation station by the Companhia de Saneamento Básico do Estado de São Paulo. The sediment was analyzed as for acute and chronic toxicity through bioassays with the cladocerans Daphnia similis and the insect Chironomus xanthus. Data treatment was done with Fisher Exact Test (mortality). The association level between the variables in sediment and ecotoxicological tests was available in non-parametric tests, through the Spearman's correlation coefficient. Oriented on the results presented in this work, pointing low concentrations of heavy metals in the sediments presented in the collect local, and the absence of toxicity, we can say that at this reservoir, at least in the collect area, it's low impacted, not implicating in direct interferences in the quality of life of benthonic organisms.


Assuntos
Zinco/toxicidade , Cádmio/toxicidade , Reservatórios de Água/prevenção & controle , Sedimentos/análise , Cobre/toxicidade , Chumbo/toxicidade , Manganês/toxicidade , Níquel/toxicidade , Brasil , Metais Pesados/toxicidade , Testes de Toxicidade Aguda/análise , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/análise , Testes de Toxicidade Crônica/métodos
7.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 14(2): 106-109, ago. 2016. ilus
Artigo em Espanhol | LILACS, BDNPAR | ID: biblio-869082

RESUMO

Ciertos fármacos que son excretados en orina, como los antibióticos, pueden formar cristales cuando la dosis empleadas son elevadas, la diuresis se encuentra disminuida o el pH de la orina es ácido. Los eventos de cristaluria medicamentosa son poco frecuentes y pueden ser cuadros asintomáticos e incluso originar fallos renales agudos. En este reporte se describen dos casos: una mujer de 26 años con cristaluria de ampicilina y una niña de 8 años con cristaluria de amoxicilina, registrados en el laboratorio de urgencias del Hospital Central del Instituto de Previsión Social. El análisis del sedimento fue realizado empleando microscopía óptica, luego los cristales fueron sometidos a microscopía de polarización y espectrofotometría infrarroja logrando la identificación exacta de la naturaleza química de los cristales. Este es el primer reporte de cristaluria medicamentosa del país y pone de manifiesto la importancia del trabajo colaborativo entre instituciones del estado.


Certain drugs that are excreted in the urine, including antibiotics, could induce theformation of crystals when the dose used is high, the diuresis is low or the pH of the urine isacid. The events of drug induced crystalluria are rare and could be asymptomatic or couldcause acute renal failure. In this report, we describe two cases: One of a 26-year-oldwoman with ampiciline crystalluria and a 8-year-old child with amoxiciline crystalluria, bothregistered at the Emergency Laboratory of the Central Hospital of the Instituto de PrevisionSocial. The analysis of the urinary sediment was made by conventional microscopy, andthen the crystals were studied by polarized light microscopy and infrared spectroscopyachieving the exact identification of the chemical nature of the crystals. This is the firstreport of drug induced crystalluria in the country and shows the importance of thecolaborative work between state institutions.


Assuntos
Humanos , Adulto , Feminino , Microscopia de Polarização , Sedimentos/análise , Espectrofotometria Infravermelho , Urina
8.
Acta toxicol. argent ; 24(1): 33-47, jul. 2016. mapas, tab
Artigo em Espanhol | LILACS | ID: biblio-837852

RESUMO

El Río Matanza-Riachuelo y sus afluentes atraviesan zonas con diferente grado de contaminación generada por las actividades agrícola-ganaderas, urbana e industrial. Los contaminantes que llegan al agua y son depositados en los sedimentos pueden ser liberados nuevamente al agua generando efectos tóxicos y/o genotóxicos sobre los organismos acuáticos. El objetivo de este trabajo fue analizar la genotoxicidad de muestras de sedimentos de la cuenca Matanza-Riachuelo obtenidas de zonas con diferentes usos del suelo. Se seleccionaron cuatro sitios de muestreo. Se utilizaron 2 métodos de extracción de contaminantes (agitación y sonicación), 2 solventes orgánicos (metanol y diclorometano) y 2 solventes inorgánicos (agua y solución ácida), obteniéndose un total de 5 extractos para cada muestra. Se realizaron mediciones de metales pesados e hidrocarburos aromáticos policíclicos (HAPs) mediante espectrofotometría de absorción atómica y CG/MS, respectivamente. La genotoxicidad se evaluó mediante el test de Ames con 2 cepas de Salmonella typhimurium (TA98 y TA100), con y sin fracción microsomal S9, y el test de Allium cepa. De los cuatro sitios estudiados, los sedimentos del Riachuelo mostraron mayores concentraciones de metales pesados y HAPs. Para el test de Ames, sólo los extractos obtenidos en diclorometano resultaron genotóxicos para la TA100 +S9 mix. Tanto los extractos inorgánicos como los orgánicos fueron citotóxicos y genotóxicos para A. cepa. Se observó una correlación negativa entre algunos compuestos HAPs y la frecuencia de micronúcleos, indicando la presencia de efectos antagónicos con otros compuestos genotóxicos. Los extractos con mayor efecto tóxico y genotóxico fueron los obtenidos con diclorometano y solución ácida. Este estudio mostró que los contaminantes orgánicos e inorgánicos extraídos de muestras de sedimento de la Cuenca Matanza-Riachuelo, con diferente grado de impacto, presentan un potencial riesgo tóxico y genotóxico para el ecosistema acuático.


The Matanza-Riachuelo River and its tributaries traverse areas with different degrees of contamination due to farming, urban and industrial activities. The pollutants entering the water are deposited in sediments, and can be released back into the water producing toxic and/or genotoxic effects on aquatic organisms. The aim of this study was to analyze the genotoxicity of sediment samples from the Matanza-Riachuelo Basin with different land uses. Four sampling sites according to the characteristics of land use were selected. Two methods of extraction (stirring and sonication), two organic solvents (methanol and dichloromethane) and two inorganic solvents (water and acid solution) were used, yielding a total of 5 extracts for each sample. Measurements of heavy metals and polycyclic aromatic hydrocarbons (PAHs) by atomic absorption spectrophotometry and GC/MS, respectively were performed. Genotoxicity was assessed using the Ames test with 2 strains of Salmonella typhimurium (TA98 and TA100) with and without S9 microsomal fraction, and the Allium cepa test. Taking into account the four sites, sediments from Riachuelo showed higher concentrations of heavy metals and PAHs. Only the dichloromethane extracts were genotoxic to the Ames test using the TA100 strain +S9 the mix. Both organic and inorganic extracts were cytotoxic and genotoxic to A. cepa. A negative correlation between some PAHs compounds and micronucleus frequency were observed, indicating the presence of antagonistic effects with other genotoxic compounds in samples. The extracts with high toxic and genotoxic effects were obtained with dichloromethane and acid solution. This study showed that organic and inorganic contaminants extracted from sediment samples from the Matanza-Riachuelo Basin, with varying degrees of impact, have potential toxic and genotoxic risk to the aquatic ecosystem.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Sedimentos/análise , Metais Pesados/isolamento & purificação , Genotoxicidade , Espectrofotometria Atômica/métodos , Poluição de Rios/análise , Cromatografia Gasosa/métodos , Testes de Mutagenicidade/métodos
9.
J. venom. anim. toxins incl. trop. dis ; 21: 1-8, 31/03/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-741604

RESUMO

Background: Toxic cyanobacterial blooms are recurrent in Patos Lagoon, in southern Brazil. Among cyanotoxins, [D-Leu1] microcystin-LR is the predominant variant whose natural cycle involves water and sediment compartments. This study aimed to identify and isolate from sediment a bacterial strain capable of growing on [D-Leu1] microcystin-LR. Sediment and water samples were collected at two distinct aquatic spots: close to the Oceanographic Museum (P1), in Rio Grande City, and on São Lourenço Beach (P2), in São Lourenço do Sul City, southern Brazil. Methods: [D-Leu1] microcystin-LR was isolated and purified from batch cultures of Microcystis aeruginosastrain RST9501. Samples of water and sediment from Rio Grande and São Lourenço do Sul were collected. Bacteria from the samples were allowed to grow in flasks containing solely [D-Leu1] microcystin-LR. This strain named DMSX was isolated on agar MSM with 8 g L−1 glucose and further purified on a cyanotoxin basis growth. Microcystin concentration was obtained by using the ELISA immunoassay for microcystins whereas bacterial count was performed by epifluorescence microscopy. The genus Pseudomonas was identified by DNA techniques. Results; Although several bacterial strains were isolated from the samples, only one, DMXS, was capable of growing on [D-Leu1] microcystin-LR. The phylogenetic analysis of the 16S rRNA gene from DMXS strain classified the organism as Pseudomonas aeruginosa. DMXS strain incubated with [D-Leu1] microcystin-LR lowered the amount of toxin from 1 μg.L−1 to < 0.05 μg.L−1. Besides, an increase in the bacterial count–from 71 × 105 bacteria.mL−1 to 117 × 105 bacteria.mL−1–was observed along the incubation. Conclusions: The use of bacteria isolated from sediment for technological applications to remove toxic compounds is viable. Studies have shown that sediment plays an important role as ...


Assuntos
Água/análise , Biodegradação Ambiental , Cianobactérias , Estuários , Microcistinas/toxicidade , Sedimentos/análise , Brasil
10.
Rev. Salusvita (Online) ; 27(2): 99-118, 2008. mapas, tab, graf
Artigo em Português | LILACS | ID: lil-562305

RESUMO

O objetivo principal do presente trabalho foi estudar o impacto dos metais dissolvidos e em sedimentos no Córrego do Cintra, localizadona cidade de Botucatu-SP, à jusante do Campus da Unesp-SP, Brasil. Os metais potencialmente tóxicos dissolvidos na água foram detectados na maioria dos locais de coleta. Os Pontos de 1 a 7 superaram o limite máximo permitido pelo CONAMA para o Cd (até 0,280 mg.L-1), Fe (5,0 a 47,79 mg.L-1), Ni (0,027 a 0,378 mg.L-1), Zn (<5,0 mg.L-1), Pb (0,033 a 0,072 mg.L-1) e Cu (0,028 a 3,82 mg.L-1). Detectaram- se também as possíveis fontes geradoras pontuais (efl uentetratado e não tratado) e difusas (agroquímicos e resíduos lixiviadosda Rodovia Marechal Rondon) que comprometem signifi cativamentea qualidade da água...


The objective of the present study was to investigate the impact of metals dissolved and in sediments in the Cintra Stream located in Botucatu city, SP, downstream Unesp Campus SP, Brazil. The potentially toxic metal dissolved in the water were detected in mostof the collection places. Points 1 to 7 surpassed the maximum index allowed by Resolution of CONAMA nº 357/2005, for the Cd (until 0,280 mg. L-1), Fe (5,0 to 47,79 mg. L-1), Ni (0,027 to 0,378mg. L-1), Zn (< 5,0 mg. L-1), Pb (0,033 to 0,072 mg. L-1), Cu (0,028 to 3,82 mg. L-1). It was also detected the possible focal generating sources (effl uent treated and not treated) and diffuse (agrochemistry and lixiviated residues of the “Marechal Rondon” high-way) that signifi cantly impairs the water quality...


Assuntos
Humanos , Animais , Masculino , Feminino , Disponibilidade Biológica , Metais/toxicidade , Poluição Química da Água , Metais/análise , Metais/efeitos adversos , Sedimentos/análise , Água/análise
11.
J. bras. nefrol ; 29(2): 90-94, jun. 2007. ilus, tab
Artigo em Português | LILACS | ID: lil-606111

RESUMO

Introdução: A sedimentoscopia urinária com microscópio munido com contraste de fase (MCF) deveria ser a primeira etapa na determinação da origemdas hematúrias. Objetivo: Avaliar discrepâncias nas descrições dos parâmetros urinários relacionados à origem das hematúrias, comparando as descrições do nefrologista (Nef) e do profissional de análises clínicas (PAC). Métodos: Urinas de pacientes com glomerulopatias (GP) confirmadas por biópsia renal foram analisadas sob MCF, por um Nef e um PAC, ambos sem conhecimento prévio da origem das amostras. Cilindros hemáticos, acantocitúria ou células G1 >5% e dismorfismo eritrocitário foram utilizados na localização glomerular das hematúrias. Resultados: Dos 28 pacientes, 13 pacientes (46,4%) apresentavam glomerulonefrites não proliferativas e 15 (53,6%) glomerulonefrites proliferativas. Comparativamente ao PAC, o Nef identificou maior número de hemácias (mediana/mL de urina, 80.000 vs 4.800, p=0,001), maior número de cilindros hemáticos (39,3% vs 0%, p=0,001), maior freqüência de acantocitúria ou células G1 >5% (35,7% vs. 7,14%, p=0,021) e de dismorfismo eritrocitário (96,2% vs 7,14%, p<0,001). As discrepâncias dos resultados permaneceram após a separação das glomerulopatias em proliferativas e não proliferativas. Conclusão: Os parâmetros urinários que caracterizam a origem da hematúria foram mais freqüentemente identificados pelo nefrologista e sugerem que a urinálise, pela sua simplicidade e grande valor informativo, deveria ser incluída obrigatoriamente nos programas de treinamento em nefrologia.


Introduction: In the assessment of hematuria, the first step should be the identification of the origin of the bleeding, which can be done easily by analyzing the urine under phase-contrast microscopy. Obective: To assess the discrepancy of reports of the urinary parameters utilized in the localization of the glomerular origin of hematuria, comparing reports by the nephrologists and by the clinical laboratory technologist. Methods: Urines of patients with biopsy proven glomerulonephritis were assessed under phase-contrast microscopy by a nephrologist and a clinical laboratory technologist, both without previous knowledge of the origin of the samples. Red blood cell (RBC) casts, urinary acanthocytes or G1 cells >5%, and erithrocyte dysmorphism were used tolocalize the glomerular bleeding. Results: Among 28 patients, 13 (46.4%) had non proliferative glomerulonephritis and 15 (53.6%) had proliferative glomerulonephritis. Relatively to the clinical laboratory technologist, the nephrologist identified more RBC (median of 80.000 vs 4.800, p= 0.001), more RBC casts (39.3% vs 0%, p=0.001), more urinary acanthocytes or G1 cells >5% (35.7% vs 7.14%, p=0.021) and more dysmorphic RBC (96.2% vs 7.14%,p<0.001). The discrepancies of the reports were maintained after the separation of the glomerulonephritis in proliferative and non proliferative. Conclusion: The urinary parameters used in characterization of the origin of the hematuria were more frequently identified by the nephrologist, and suggest that the urinalysis, a simple and very informative test, should be mandatory in programs of training in nephrology.


Assuntos
Humanos , Masculino , Feminino , Adulto , Acantócitos , Hematúria/diagnóstico , Sedimentos/análise , Urina , Microscopia de Contraste de Fase
12.
Acta cient. venez ; 57(4): 149-158, 2006. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-537094

RESUMO

En Punta El Chaure por una extensión de 263 m se ubica un estrato de espesor variable entre 0,23 y 1,35 m. de dunas fósiles presumiblemente pleistocenas; hacia el NE, el depósito permanece recubierto alternativamente por sedimentos eólicos actuales y hacia el SW entran en contacto con los acantilados inactivos de El Chaure. La existencia de este modelado plantea consideraciones paleogeográficas de interés para la evolución de la costa norte de Paraguaná. Los objetivos del trabajo son: a) Establecer las características sedimentológicas de las formas topográficas estudiadas b) Identificar los procesos bajo los cuales evolucionan actualmente. c) Caracterizar las formas geomorfológicas actuales. La metodología utilizada se basa en trabajo de campo, análisis petrográfico de secciones finas, tamizado en seco, curvas granulométricas, parámetros estadísticos, análisis morfoscópico y calcimetría. Se concluye que las eolianitas en campo, se presentan como areniscas de grano medio a fino, bien cementadas de color crema con estratificación cruzada, observándose en las secciones finas abundante cuarzo detrítico. La redondez varía desde subangular en las tallas medias a subredondeada en las más gruesas. La selección es moderada a pobre, la asimetría negativa y la curtosis leptocúrtica. Estos resultados difieren de los depósitos actuales. El contenido de carbonato de calcio es superior al 50 por ciento en ambos casos. Las dunas fósiles presentan rasgos de morfología cárstica que favorecen el desmantelamiento.


A probable Pleistocene fossil dunes layer is located at Punta El Chaure, its thickness varies from 0,23 to 1,35 m and its extension goes about 263 m towards NE, the layer is covered by aeolian sediments and it makes contact with inactive cliff to SW. The presence of these deposits raises important paleogeographic considerations for Paraguaná north coast evolution studies. The objectives of this research are: a) to establish sedimentary characteristics of these topographic forms, b) to identify present evolution processes, and c) to characterize actual geomorphologic forms. The methodology used was based on field work, petrography analysis of thin sections, dry sieving, statistic parameters, granulemetric curves, morphologic analysis, and calcium content. Conclusions: Cream eolianites are found in field with cross stratification and good cementation of sandstone. Main grain size ranges from medium to fine. Abundant detritic quartz is observed under microscope. Roundness varies from sub-angular in medium sizes to sub–rounded in thick ones. Statistic parameters show a selection from moderate to poor, negative asymmetry and leptokurtic kurtosis. These results differ from actual deposits. The content of Calcium Carbonate is higher than 50 percent in both cases. Fossil dunes show karsts morphology traits which facilitate dismantlement.


Assuntos
Areia , Sedimentos/análise , Sedimentos/classificação , Geologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA