Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Bull Environ Contam Toxicol ; 101(2): 160-165, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29721597

RESUMEN

We examined the sediments of four coastal lagoons (Ria Lagartos, Bocas de Dzilam, Laguna de Chelem and Ria Celestun) from the state of Yucatan, Mexico, for three widely used commercial polybrominated diphenyl ethers formulations (penta-, octa- and deca-BDE). The most commonly found congeners in all four lagoons were BDEs 47, 99 and 100 (all in the penta-BDE formulation) and BDE209 (deca-BDE formulation). The greatest variety and highest concentrations of brominated flame retardants were found in Ria Lagartos, which also showed the highest BDE 100 concentration (24.129 ng/g). Hexabromocyclododecane was found in all lagoons, but at lower concentrations than those of the various polybrominated diphenyl ethers. Dispersal routes of these compounds are discussed, such as a ring of sinkholes (cenotes) adjacent to the lagoons. Moreover, electronic waste is a serious problem because municipal landfills have been the primary disposal method for these wastes and therefore represent a reservoir of brominated fire retardants.


Asunto(s)
Retardadores de Llama/análisis , Sedimentos Geológicos/análisis , Éteres Difenilos Halogenados/análisis , Hidrocarburos Bromados/análisis , Monitoreo del Ambiente , Estuarios , México
2.
Chemosphere ; 92(3): 309-16, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23602656

RESUMEN

In the present study the occurrence of emerging hydrophobic organic pollutants in sediment samples from South America (Chile and Colombia) was investigated for the first time. Nineteen Chilean and thirteen Colombian sediment samples were analyzed in order to determine their content of brominated flame retardants (BFRs) (including PBDEs and emerging BFRs) as well as UV filters (UV-F). Samples were collected from neighboring aquatic ecosystems highly urbanized and industrialized in Colombia (Magdalena River area) and Chile (Biobio region). Different analytical procedures were applied depending on the selected analytes, based on chromatographic and mass spectrometric methodologies (GC-MS and LC-MS-MS). In general, concentration levels of both BFRs (up to 2.43 and 143ngg(-1) dw of PBDEs in Chile and Colombia, respectively) and UV-F (nd-2.96 and nd-54.4ngg(-1) dw in Chile and Colombia, respectively) were in the low range of published data, and the contribution of BFRs was higher than that of UV-F for almost all the sampled sediments.


Asunto(s)
Contaminantes Ambientales/análisis , Contaminantes Ambientales/química , Sedimentos Geológicos/química , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos Orgánicos/análisis , Compuestos Orgánicos/química , Rayos Ultravioleta , Chile , Colombia , Retardadores de Llama/análisis , Hidrocarburos Bromados/análisis , Hidrocarburos Bromados/química
3.
Environ Pollut ; 178: 23-32, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23524177

RESUMEN

We developed a model for evaluating the environmental risk of persistent organic pollutants (POPs) to aquatic organisms. The model is based on fuzzy theory and uses information provided by international experts through a questionnaire. It has been tested in two case studies for a particular type of POPs: brominated flame retardants (BFRs). The first case study is related to the EU-funded AQUATERRA project, with sampling campaigns carried out in two Ebro tributaries in Spain (the Cinca and Vero Rivers). The second one, named the BROMACUA project, assessed different aquatic ecosystems in Chile (San Vicente Bay) and Colombia (Santa Marta Marsh). In both projects, the BFRs under study were polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). However, the model can be extrapolated to other POPs and to different aquatic ecosystems to provide useful results for decision-makers.


Asunto(s)
Monitoreo del Ambiente/métodos , Modelos Químicos , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Chile , Colombia , Ecosistema , Retardadores de Llama/análisis , Lógica Difusa , Éteres Difenilos Halogenados/análisis , Hidrocarburos Bromados/análisis , Medición de Riesgo/métodos , España
4.
Environ Pollut ; 170: 152-60, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22797349

RESUMEN

Liver samples from 53 Franciscana dolphins along the Brazilian coast were analyzed for organobrominated compounds. Target substances included the following anthropogenic pollutants: polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), as well as the naturally-generated methoxylated-PBDEs (MeO-PBDEs). PBDE concentrations ranged from 6 to 1797 ng/g lw (mean 166 ± 298 ng/g lw) and were similar to those observed in cetaceans from Northern Hemisphere. PBBs were found in all sampling locations (

Asunto(s)
Delfines/metabolismo , Monitoreo del Ambiente , Hidrocarburos Bromados/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Océano Atlántico , Brasil , Femenino , Retardadores de Llama/análisis , Retardadores de Llama/metabolismo , Éteres Difenilos Halogenados/análisis , Éteres Difenilos Halogenados/metabolismo , Hidrocarburos Bromados/análisis , Hígado/metabolismo , Masculino , Bifenilos Polibrominados/análisis , Bifenilos Polibrominados/metabolismo , Contaminantes Químicos del Agua/análisis
5.
Mar Pollut Bull ; 62(11): 2463-8, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21925687

RESUMEN

Halogenated natural products (HNPs) are frequently detected in marine organisms. High HNP concentrations have previously been found in marine mammals from the Great Barrier Reef, Australia, including in the blubber of herbivorous dugongs (Dugong dugon). To identify the source of HNPs we initially focused on the analysis of Australian seagrass (Halophila ovalis) which serves as the principal food source for dugongs. GC/MS analysis of the seagrass indicated the presence of several organobromine compounds. One compound was identified as 2,3,4,5-tetrabromo-1-methylpyrrole (TBMP) by synthesis. Subsequent analysis of semipermeable membrane devices demonstrated that the photo-sensitive TBMP is widespread in the Great Barrier Reef (Queensland, Australia). The detection of larger TBMP concentrations in fish fillets from Chile and traces in mussels from New Zealand indicated that this potential HNP may be distributed throughout the Southern Pacific Ocean.


Asunto(s)
Bivalvos/química , Monitoreo del Ambiente/estadística & datos numéricos , Hidrocarburos Bromados/análisis , Hydrocharitaceae/química , Salmo salar/metabolismo , Plantas Tolerantes a la Sal/química , Animales , Chile , Arrecifes de Coral , Cromatografía de Gases y Espectrometría de Masas , Nueva Zelanda , Océano Pacífico , Queensland
6.
J AOAC Int ; 92(5): 1366-72, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19916374

RESUMEN

A sensitive and specific LC/MS/MS method was developed and validated for the determination of scopolamine butylbromide in human plasma. Scopolamine butylbromide and propanolol (internal standard) were extracted from the plasma by liquid-liquid extraction with dichloromethane as the extraction solvent and separated on a C18 analytical column (50 x 4.6 mm id) maintained at 40 degrees C. The analytes were eluted at a constant flow rate of 0.45 mL/min; the mobile phase consisted of acetonitrile and a buffer of 5 mM ammonium acetate and 0.1% formic acid (60 + 40, v/v). The mass spectrometer, equipped with an electrospray source in the positive ionization mode, was set up in the multiple-reaction monitoring mode to monitor the transitions m/z 360.6 > 102.5 (scopolamine butylbromide) and m/z 259.7 > 115.6 (propanolol). The chromatographic separation was obtained within 2.0 min, and the responses were linear over the concentration range of 0.10-40.00 ng/mL. The mean extraction recoveries of scopolamine butylbromide and propanolol from plasma were 69.00 and 80.76%, respectively. Method validation parameters, such as specificity, linearity, precision, accuracy, and stability, were within the acceptable range. Moreover, when the proposed method was successfully applied to a pharmacokinetic study of healthy human volunteers, the results showed that the two scopolamine butylbromide formulations tested are not bioequivalent in rate and extent of absorption.


Asunto(s)
Química Farmacéutica/métodos , Cromatografía Liquida/métodos , Hidrocarburos Bromados/análisis , Hidrocarburos Bromados/sangre , Escopolamina/análisis , Escopolamina/sangre , Espectrometría de Masas en Tándem/métodos , Acetatos/análisis , Adolescente , Adulto , Técnicas de Química Analítica , Femenino , Formiatos/análisis , Humanos , Masculino , Plasma/efectos de los fármacos , Reproducibilidad de los Resultados , Solventes/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Temperatura
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA