Consulta: subjectFacets:"Arsenic"
Registros recuperados: 21
Data/hora: 01/06/2024 08:13:25

L'arsenic en milieu marin: Synthese bibliographique
Provedor de dados: 5
Autores: Michel, Pierre.
Arsenic is an important element in marine environment due to its level 1,000 times higher that of mercury and its behavior close to that of  phosphorus. This overview recalls few chemical and biochemical basis and presents the current state of knowledge about its sources, concentration levels in estuarine and oceanic waters, sediments and biota. Toxicity for species, ecosystems and consumers, and analytical methods for its control are approached.
Tipo: Text
Palavras-chave: Environmental impact; Literature reviews; Toxicity; Arsenic; Metals.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/publication-1779.pdf

Behaviour of arsenic on the continental shelf off the Gironde estuary: role of phytoplankton in vertical fluxes during spring bloom conditions
Provedor de dados: 5
Autores: Michel, Pierre; Boutier, Bernard; Herbland, Alain; Averty, Bernard; Artigas, Lf; Auger, Dominique; Chartier, E.
The arsenic (As) cycle in the marine environment is known to be sensitive to biological activity. Within the scope of the National Coastal Oceanography Program, we undertook a specific study of the behaviour of this element in a water column on the continental shelf of the Bay of Biscay off the Gironde estuary during two oceanographic cruises conducted in May 1994 and May 1995. Various chemical forms were measured: arsenite (As3), at-senate (As5), monomethylarsenic (MMA), dimethylarsenic (DMA) and dissolved total As after ultraviolet mineralization. The net flux of total As from the Gironde estuary was evaluated as well as its effect on the concentration in surface marine waters. The vertical profiles in the coastal zone during a period of active primary...
Tipo: Text
Palavras-chave: Arsenic; Phytoplankton; Speciation; Gironde plume; Biscay Bay.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/1998/publication-851.pdf

Accumulation of nine metals and one metalloid in the tropical scallop Comptopallium radula from coral reefs in New Caledonia
Provedor de dados: 5
Autores: Metian, M.; Bustamante, Paco; Hedouin, L.; Warnau, M.
Uptake of waterborne Cd, Co, Mn and Zn was determined in laboratory experiments using radiotracer techniques (Cd-109, Co-57, Mn-54 and Zn-65). Labelled Zn was mainly accumulated in the digestive gland (65%) and Co in kidneys (81%); Cd and Mn were similarly distributed in digestive gland and gills. In a complementary field study, Ag, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, and Zn were analysed in scallops collected at two stations showing different contamination levels. Digestive gland and kidneys displayed the highest concentrations. Ag, As, Cd, and Fe differed in soft tissues from the two stations, suggesting that Comptopallium radula could be a valuable local biomonitor species for these elements. Low Mn and Zn concentrations found in kidneys suggest that their...
Tipo: Text
Palavras-chave: Bioindicator species; Risk assessment; Pectinidae; Radiotracers; Arsenic; Trace elements; Tropical environment.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6953.pdf

Importance de la spéciation des métaux et composés organométalliques pour une bonne évaluation des risques environnementaux en milieu marin. Cas du mercure, de I'arsenic et de l'étain
Provedor de dados: 5
Autores: Michel, Pierre.
Methylmercury toxicity for sea-food consumers is well known long time ago. Tributyltin used as antifouling in paints is toxic at a level as low as 1 ng/l for oysters gastropod. At the opposite, organoarsenic compounds and especially arsenobetaine from fishes are much less toxic than inorganic species. Moreover, besides toxicological considerations, the biogeochemical fates of these elements need a good knowledge of the chemical forms of environmental inputs and of their behaviour in the various compartments (waters, sediments, biota). These phenomenons will be better understood by discussing typical applications.
Tipo: Text
Palavras-chave: Composés organométalliques; Mercure; Arsenic; Étain; Biogéochimie; Organometallic compounds; Mercury; Arsenic; Tin; Biogeochemistry.
Ano: 1992
URL: https://archimer.ifremer.fr/doc/00480/59138/61766.pdf

L'arsenic en milieu marin. Biogeochimie et ecotoxicologie
Provedor de dados: 5
Autores: Michel, Pierre.
Arsenic levels of in the marine environment are high in comparison with other contaminants. Over the past twenty years, a large number of arsenic organic compounds have been identified in the water, sediments and living species. This document constitutes a synthesis of current knowledge on arsenic sources, and contamination levels, on its biogeochemical cycle as well as its toxic effects on human and marine fauna. This paper highlights in particular the effects of phosynthesis on arsenic speciation and its distribution throughout the marine environment. Problems of toxicity in the case of certain phyto- and zooplankton species are identified. Bioaccumulation in seaweeds, molluscs and fishes is documented as well, with special attention to the species...
Tipo: Text
Palavras-chave: Ecotoxicology; Contamination; Biogeochemistry; Arsenic; Ecotoxicologie; Contamination; Biogéochimie; Arsenic.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/rapport-1448.pdf

Protective Role of Melatonin in Mouse Spermatogenesis Induced by Sodium Arsenite
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Poblete,Daniel; Catriao,Roberto; Fernandes,Fábio Henrique.
Arsenic is a testicular environmental toxic. Melatonin (Me), being a potent antioxidant, may reduce the damage caused by arsenic in male fertility. The effects of daily oral exposure of Sodium Arsenite (As; 7.0 mg/kg/bw); Melatonin (Me, 10.0 mg/kg/bw); Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw), and Negative Control (NaCl 0.9%) in male CF-1 adult mice were assessed in acute (8.3 days), chronic (33.2 days) and recovery (66,4 days) of testicular damage. We evaluated changes in testicular weight and histopathological, morphometric measurements, expression of COX-2 and Androgen Receptor (AR) antigens and lipid peroxidation levels. Treatment resulted in decreased tubular diameter and AR expression, and increased: interstitial area, luminal diameter, COX-2...
Tipo: Journal article
Palavras-chave: Mouse; Arsenic; COX-2; Androgen receptor; Oxidative stress; Melatonin.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022013000300012

Melatonin Protective Role in Mouse Cauda Epipidymal Spermatozoa Damage Induced by Sodium Arsenite
Provedor de dados: 77
Autores: Bustos-Obregón,Eduardo; Poblete,Daniel; Catriao,Roberto; del Sol,Mariano; Fernandes,Fábio Henrique.
We evaluated the sperm parameters such as cauda epididymis weight, sperm count, sperm morphology and sperm DNA stability of adult CF-1 male mice treated daily (oral exposure) with the toxic sodium arsenite (As, 7.0 mg/kg/body weight); Melatonin (Me, 10.0 mg/kg/bw), Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw) and Negative Control (NaCl 0.9%) to assess acute (8.3 days), chronic (33.2 days) and recovery of testicular damage (66.4 days). Arsenic decreases the number of sperm from chronic treatment (33.2 days) and this effect continued until 66.4 days of treatment. The toxic effect of As also altered the morphology of spermatozoa in all treatment periods when compared to the negative control group. However, Metalonin induced protective effects in periods of 33.2...
Tipo: Journal article
Palavras-chave: Mouse; Melatonin; Arsenic; Sperm; DNA stability.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022013000400017

EFFECTS OF PHOSPHORUS FERTILIZATION ON ARSENIC UPTAKE BY WHEAT GROWN IN POLLUTED SOILS
Provedor de dados: 126
Autores: Pigna,M; Cozzolino,V; Giandonato Caporale,A; Mora,M.L; Di Meo,V; Jara,A.A; Violante,A.
In this study we have examinated the results of two experiments on the uptake and distribution of arsenic (As) in roots, shoots, and grain of wheat grown in As-polluted soils and in an unpolluted soil irrigated with As-contaminated water in absence or presence of phosphorus (P) fertilization. Arsenic concentrations in wheat samples of the two experiments are higher than those in the plants grown on uncontaminated soil. In the experiments showed in this work, it is highlighted the role of P fertilization in preventing As uptake and translocation in wheat plants. These findings could have important implications to reduce the potential risk posed to human health by As entering the food-chain.
Tipo: Journal article
Palavras-chave: Phosphorus fertilization; Arsenic; Wheat; Polluted soils.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-95162010000200004

Toxicity and accumulation of arsenic in wheat (Triticum aestivum L.) varieties of China
Provedor de dados: 85
Autores: Zhang,WD; Liu,DS; Tian,JC; He,FL.
Soil arsenic contamination becomes a potential agricultural and environmental hazard worldwide, and has been a serious problem for safe food production. A field experiment on soil contamination was conducted on four wheat varieties (Jimai, Gaoyou, Weimai and Wennong) in Eastern China, using 50 or 100 mg arsenic/kg soil. Biomass production and yield components were determined and arsenic concentrations were measured in plant tissues. Differential arsenic effects on wheat varieties were determined at maturity. Results showed that addition of arsenic significantly (p&lt;0.05) reduced root, stem and spike dry weight and yield components, which resulted in the decrease of grain yield per plant. Arsenic concentrations in plant tissues increased significantly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arsenic; Wheat (Triticum aestivum L.); Biomass; Yield components; Arsenic toxicity.
Ano: 2009
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572009000200011

Estimating Economic Health Costs of Not Controlling Toxic Water Pollution
Provedor de dados: 31
Autores: Easter,   K. William; Konishi,   Yoshifumi.
The purpose of this paper is to determine what types of information may be important in determining the welfare benefits of preventing toxic water contamination when a given type of toxification occurs (or is likely to occur) in a given setting. It attempts to identify information and behavior issues that need to be considered when policy makers and others wish to obtain reasonable estimates of welfare benefits and weigh them against the economic costs of removing toxins. This paper also provides reasonable "scenarios" for three toxic pollutants that are found in water bodies (surface water or groundwater). We make use of two country alternatives--one in developing countries and the other in developed countries--to demonstrate, with specific examples of...
Tipo: Conference Paper or Presentation
Palavras-chave: Welfare costs; Arsenic; Mercury; Atrazine; Information; Water; Environmental Economics and Policy; Health Economics and Policy.
Ano: 2006
URL: http://purl.umn.edu/25768

Multi-criteria analysis for the impact assessment of food safety policies: The case of EU regulation on dietary arsenic
Provedor de dados: 31
Autores: Ragona,   Maddalena; Mazzocchi,   Mario; Alldrick,   A.J.
Developments in knowledge concerning the toxicology and occurrence of dietary arsenic suggest that levels of exposure in some groups of the population within the EU are a cause for concern. This applies also in the case of individual Member States where local regulatory limits exist. The situation is such that some foods on the market are already the subject of consumer advice provided by government agencies. In the light of these considerations, some have suggested that Member States’ legislation concerning arsenic in foods should be modified and harmonised to reflect such developments. An evaluation of alternative policy initiatives is considered in this work. It employed a computer-based, fuzzy multi-criteria impact assessment tool for the...
Tipo: Presentation
Palavras-chave: Multi-criteria analysis; Fuzzy; Regulatory impact assessment; Food safety regulations; Arsenic; Food Consumption/Nutrition/Food Safety; C02; C65; D81; Q18.
Ano: 2012
URL: http://purl.umn.edu/124122

Advanced Methods for Dose-Response Assessment: Bayesian Approaches - Final Report
Provedor de dados: 31
Autores: Wilson,   James D.
Resources for the Future (RFF), in conjunction with the U.S. Environmental Protection Agency, the Society for Risk Analysis, and the Electric Power Research Institute, held a workshop Sept. 18-20, 2000, at the RFF Conference Center in Washington, DC. The intent was to discuss how Bayesian approaches could be useful in improving techniques for estimating exposure-response functions. Ten distinguished scholars from a range of fields (medical biostatistics, decision sciences, environmental engineering, and toxicology) served as faculty. Approximately 80 people attended the workshop. Bayesian methods have been applied to a variety of problems in biomedical research and environmental risk analysis, including design of clinical trials, estimation of exposures to...
Tipo: Working or Discussion Paper
Palavras-chave: Bayesian analysis; Dose-response; Regulation; Risk assessment; Arsenic; Risk and Uncertainty.
Ano: 2001
URL: http://purl.umn.edu/10754

Induction of a geochemical barrier for As, Fe and S immobilization in a sulfide substrate
Provedor de dados: 90
Autores: Assis,Igor Rodrigues de; Dias,Luiz Eduardo; Ribeiro Jr,Emerson Silva; Abrahão,Walter Antônio Pereira; Mello,Jaime Wilson Vargas de; Veloso,Renato Welmer.
Acid mine drainage (AMD) is an environmental concern due to the risk of element mobilization, including toxic elements, and inclusion in the food chain. In this study, three cover layers were tested to minimize As, Fe and S mobilization from a substrate from former gold mining, containing pyrite and arsenopyrite. For this purpose, different layers (capillary break, sealant and cover layer) above the substrate and the induction of a geochemical barrier (GB) were used to provide suitable conditions for adsorption and co-precipitation of the mobilized As. Thirteen treatments were established to evaluate the leaching of As, Fe and S from a substrate in lysimeters. The pH, As, Fe, S, Na, and K concentrations and total volume of the leachates were determined....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Jarosite; Arsenic; Cover layers; Gold mining; Rehabilitation.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000200036

Role of glutathione in tolerance to arsenite in Salvinia molesta, an aquatic fern
Provedor de dados: 39
Autores: Silva,Adinan Alves da; Oliveira,Juraci Alves de; Campos,Fernanda Vidal de; Ribeiro,Cleberson; Farnese,Fernanda dos Santos.
ABSTRACT In many plant species, tolerance to toxic metals is highly dependent on glutathione, an essential metabolite for cellular detoxification. We evaluated the responses of glutathione metabolism to arsenite (AsIII) in Salvinia molesta, an aquatic fern that has unexplored phytoremediation potential. Plants were exposed to different AsIII concentrations in nutrient solution for 24 h. AsIII caused cell membrane damage to submerged leaves, indicating oxidative stress. There was an increase in the glutathione content and ϒ-glutamylcysteine synthetase enzyme activity in the submerged and floating leaves. The glutathione peroxidase and glutathione sulfotransferase enzymes also showed increased activity in both plant parts, whereas glutathione reductase only...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arsenic; Glutathione; Macrophytes; Oxidative stress; Phytoremediation.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000400657

Assessment of heavy metal residues in Brazilian poultry and swine tissue
Provedor de dados: 45
Autores: Alkmim Filho,J. F.; Germano,A.; Dibai,W.L.S.; Vargas,E.A.; Melo,M.M.
The aim of this study was to investigate the presence of arsenic, lead and cadmium residues in samples of liver, kidney and muscle of poultry and swine during the years from 2002 to 2008. A total of 1978 samples were analyzed: 1031 of poultry and 947 of swine from Brazilian slaughterhouses. The samples were analyzed at the National Agricultural Laboratory using the atomic absorption spectrometry technique. In poultry, the arsenic residues were detected in 53.6% of liver samples, although no results have exceeded the MRL. In kidneys, 39.7% of the samples showed measurable residues and there was no violation of the limits. Regarding lead, there were 5 contaminated liver samples and 24 contaminated kidney samples (1.5 and 3.6% respectively). In muscle tissue...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Trace elements; Arsenic; Cadmium; Lead.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352014000200022

Effectiveness of zinc in modulating perinatal effects of arsenic on the teratological effects in mice offspring
Provedor de dados: 48
Autores: Ahmad,Mohammad; Wadaa,Mohammad A. M; Farooq,Muhammad; Daghestani,Maha H; Sami,Ahmed S.
Exposure to arsenic via drinking water is considered as a worldwide problem. Studies have shown that arsenic exposure during pregnancy affects embryogenesis and offspring development in rats and mice. Zinc as a micronutrient regulates many physiological functions, including an antioxidative role under various toxic conditions. However, studies on the perinatal protective effect of zinc on offspring need further attention. The present study was designed to evaluate the potential protective role of zinc in mitigating the adverse effects in the offspring of arsenic exposure during pregnancy. The arsenic (40mg/kg body weight) and zinc (4% w/v) doses formed the only drinking fluid source for the experimental groups of dams during the perinatal period of the...
Tipo: Journal article
Palavras-chave: Arsenic; Zinc; Perinatal; Mice offspring; Sensory motor reflexes; Behavior; Oxidative stress.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602013000200003

Arsenic tolerance of Microcystis novacekii (Komárek-Compère, 1974) and its arsenic decontamination potential
Provedor de dados: 52
Autores: Ferreira,Fernanda Aires Guedes; Franco,Maione Wittig; Oliveira,Dirce Maria De; Magalhães,Sérgia Maria Starling; Barbosa,Francisco Antônio Rodrigues.
ABSTRACT Cyanobacteria possess metallic ion interaction properties that should be explored with the aim of recovering arsenic (As) contaminated areas. Contamination of As is an issue of worldwide concern due to the risk of human chronic intoxication and negative environmental health effects. In this study the potential decontamination of As(III) and As(V) using cyanobacteria cultures was assessed. Microcystis novacekii (Komárek-Compere, 1974) showed normal growth in concentrations of As(V) similar to those found in natural environments contaminated with As, demonstrating its resistance to As(V). Growth rates gradually decreased upon exposure to high As(V) concentrations from 600 to 5630 mg.L-1 while As(III) affected growth from 14.7 - 85.7 mg.L-1. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arsenic; Cyanobacteria; Bioaccumulation; Toxicity; Growth rates.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132018000100414

Draft genome sequence of Exiguobacterium aurantiacum strain PN47 isolate from saline ponds, known as “Salar del Huasco”, located in the Altiplano in the North of Chile
Provedor de dados: 58
Autores: Strahsburger,Erwin; Zapata,Felipe; Pedroso,Inti; Fuentes,Derie; Tapia,Paz; Ponce,Raul; Valdes,Jorge.
ABSTRACT In this report, we present a draft genome of 2,886,173 bp of an Exiguobacterium aurantiacum strain PN47 isolate from the sediment of a saline pond named “Salar del Huasco” in the Altiplano in the North of Chile. Strain PN47 encodes adaptive characteristics enabling survival in extreme environmental conditions of high heavy metal and salt concentrations and high alkalinity.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alkaline; Arsenic; Heavy metals; Pigments.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000100007

Effect of Phytoaccumulation of Arsenic and Chromium on Structural and Ultrastructural Changes of Brake Fern (Pteris vittata)
Provedor de dados: 61
Autores: Sridhar,Balaji B. Maruthi; Han,Fengxiang X.; Diehl,Susan V.; Monts,David L.; Su,Yi.
Structural and ultrastructural changes caused by bioaccumulation of As and Cr in brake fern (Pteris vittata), a known arsenic hyperaccumulator, were investigated. Potted plants of brake fern were exposed to metal treatments of As and Cr for three weeks. Leaf, stem and root samples were collected periodically and fixed for LM (Light Microscopy), SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy) to evaluate anatomical changes. The fresh weights, dry weights, RWC (Relative Water Content) and plant heights were obtained before the brake fern plants were harvested for metal accumulation analysis. The As accumulated mainly in the shoots while Cr accumulated mainly in the roots of the metal-treated plants. Significant changes in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anatomy; Arsenic; Chromium; Hyperaccumulator; Microscopy; Phytoremediation; Pteris vittata; Translocation; Ultrastructure.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000400006

Phytochelatins
Provedor de dados: 61
Autores: Inouhe,Masahiro.
Phytochelatins (PCs) were first discovered as Cd-binding "Cadystins A and B" in a fission yeast and then in many plants as the major components of Cd-binding complexes. PCs have the general structure of (gamma-glutamyl-cysteinyl)n-glycine (n=2-11) and the variants with the repeated gamma-glutamyl-cysteinyl units are formed in some plants and yeast. They are capable of binding to various metals including Cd, Cu, Zn or As via the sulfhydryl and carboxyl residues, but their biosyntheses are controlled preferentially by the metal Cd or metalloid As. PCs are synthesized from glutathione (gamma-glutamyl-cysteinyl-glycine) in steps mediated by PC synthase. Genes (CAD1, PCS1) of the enzyme have been isolated from plants, fission yeast and some animals. Inhibition...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arsenic; Cadmium-binding peptides; Heavy metal-tolerance; Phytochelatin; Phytoremediation.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000100006

Arsenic, cadmium and lead concentrations in Yerba mate commercialized in Southern Brazil by inductively coupled plasma mass spectrometry
Provedor de dados: 65
Autores: Santos,Lisia Maria Gobbo dos; Vicentini Neto,Santos Alves; Iozzi,Giovanna; Jacob,Silvana do Couto.
ABSTRACT: “Mate” or “Yerba Mate” (Ilex paraguariensis) is a native South American plant, commonly consumed in Argentina, Paraguay, Uruguay and southern Brazil. Recent research has detected the presence of many vitamins and metals in this plant. Theses metals are also part of yerba mate’s mineral composition, due to soil and water contamination by pesticides and fertilizers, coal and oil combustion, vehicle emissions, mining, smelting, refining and the incineration of urban and industrial waste. Regardless of their origin, some inorganic elements, such as arsenic, cadmium and lead, are considered toxic, since they accumulate in all plant tissues and are, thus, introduced into the food chain. In this context, the aim of the present study was to determine and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arsenic; Cadmium; Lead; ICP-MS; Yerba mate.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782017001200751