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1.
Sci Total Environ ; 905: 166828, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37690766

RESUMO

This study investigates the role of floating plastics as integrative samplers of organic contaminants. To this end, plastics items were collected in two Western Mediterranean coastal areas: the Mar Menor lagoon, and the last transect of Ebro river. Floating plastics were identified and characterized by attenuated total reflection Fourier-transform infrared spectrometry. Then, organic contaminants were extracted from plastic items by ultrasonic extraction with methanol, and the concentrations of 168 regulated and emerging contaminants were analysed. These compounds were analysed by stir bar sorptive extraction coupled to gas chromatography-mass spectrometry (GC-MS), except for bisphenol analogues, which were analysed with a ultraperformance liquid chromatography pump coupled to a triple quadrupole mass spectrometer (UHPLC-MS/MS), and pharmaceutical compounds, determined by UPLC coupled to hybrid triple quadrupole-linear ion trap mass spectrometer (UPLC-MS/MS). All the contaminants groups considered were detected in the samples, being particularly relevant the contribution of plastic additives. The most frequently detected contaminants were UV-filters, PAHs, pharmaceuticals and synthetic musks. Apart from plasticizers, the individual contaminants octocrylene, homosalate, galaxolide, salycilic acid and ketoprofen were frequently detected in plastics items. The results pointed out to urban and touristic activities as the main sources of pollution in the coastal areas investigated. The utility of floating plastics as integrative samplers for the detection of organic contaminants in aquatic ecosystems has been demonstrated.


Assuntos
Espectrometria de Massas em Tandem , Poluentes Químicos da Água , Cromatografia Líquida , Ecossistema , Cromatografia Gasosa-Espectrometria de Massas , Poluentes Químicos da Água/análise , Plásticos/análise
2.
Int J Oral Maxillofac Surg ; 52(2): 237-244, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35985912

RESUMO

The purpose of this work was to prospectively correlate the most characteristic clinical symptoms of temporomandibular disorders, such as pain and limitation of mouth opening, with the findings of magnetic resonance imaging (disc position, degenerative changes, and effusion) and arthroscopy findings (roofing, synovitis, chondromalacia, adhesions, and perforations). These examinations were performed in 298 patients diagnosed with internal derangement refractory to conservative treatment. The mean age of the patients was 38.59 years; 92.6% were female. The t-test and one-way analysis of variance (ANOVA) were used to correlate the findings. Significant relationships were found between pain and disc displacement without reduction (P = 0.033) and effusion (P = 0.003) on MRI, coinciding with correlations between pain and roofing of 0-25% (P = 0.016) and synovitis (P = 0.001) on arthroscopy. A significant relationship was also observed between mouth opening limitation and the presence of osteoarthrosis (P = 0.018) on MRI, and between mouth opening limitation and synovitis (P = 0.022), chondromalacia (P = 0.002), and adhesions (P < 0.001) on arthroscopy. All of these findings were observed in patients with a poor initial clinical situation, which highlights the considerable potential of correlating these data with imaging and arthroscopy findings.


Assuntos
Doenças das Cartilagens , Luxações Articulares , Sinovite , Transtornos da Articulação Temporomandibular , Humanos , Feminino , Adulto , Masculino , Artroscopia/métodos , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/cirurgia , Sinovite/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Dor , Luxações Articulares/diagnóstico , Aderências Teciduais , Amplitude de Movimento Articular
3.
Anal Chim Acta ; 1142: 179-188, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33280695

RESUMO

Most of the plastics produced worldwide are finally disposed into the environment, most of them being one-use plastic packaging. Once released, plastics may undergone degradation through several agents, such as solar radiation, mechanical forces, and microbial action. Weathered plastics and microplastics (MPs) collected from the marine environment show considerable physical and chemical differences regarding their pristine counterparts; most notably on their surface, where spectrometric measurements are done. Hence, it is crucial to consider aging for their correct identification and quantification in environmental monitoring. Five of the most common polymers employed worldwide for packaging (LDPE, HDPE, PS, PP and PET) were weathered in a pilot-scale system simulating dry and marine conditions for more than 10 weeks. Aliquots were withdrawn periodically to monitor their weathering processes by means of infrared spectrometry and scanning electron microscopy; their spectra were compared and band ratios calculated. Results showed that an individual study of each polymer is necessary since degradation pathways and products depend on the polymer type. Moreover, including spectra of weathered polymers in the spectral libraries to obtain reliable identifications in microplastics pollution studies was critical.

4.
Talanta ; 162: 648-653, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27837884

RESUMO

In this work, a new reliable, simple and fast method for the determination of six PAEs in sediments, based on ultrasonic solvent extraction (USE) followed by head space solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry determination (GC-MS), is proposed. The extraction parameters were studied, and the most favourable conditions were selected. The analytical features of the method were calculated: matrix effect, accuracy (ranged from 90% to 111%), repeatability and intermediate precision (RSD <10%), detection and quantification limits of the method (ranged from 0.001µgg-1 (DOP) to 0.142µgg-1 (DEP)), and satisfactory results were obtained. Major advantages of this approach are low consumption of reagents and solvents, no clean-up or evaporation steps were required and minimum sample manipulation. In addition, cross contamination from glassware, solvents and samples is minimized, thus procedural blanks are keeping to a minimum.. The applicability of the proposed method was demonstrated analysing sediment samples from Galician coast (NW Spain). The proposed method allows the application in routine laboratory conditions and its implementation in environmental monitoring studies under the European Water Framework Directive (WFD) and Marine Strategy Framework Directive (MSFD).

5.
J Chromatogr A ; 1385: 85-93, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25678317

RESUMO

The European Union Water Framework Directive (2013/39/EU) sets very restrictive environmental quality standards for 45 priority substances and other pollutants, including organotin compounds (OTCs). Therefore, it is necessary to develop analytical methods in compliance with the environmental quality standard (EQSs) proposed to protect the aquatic environment and humans. The proposed method (HS-SPME-GC-QqQ-MS/MS) allows the determination of OTCs, i.e. monobutyltin (MBT), dibutyltin (DBT) and TBT in water in the range of few ng L(-1). The method is nearly full automated, sensitive and simple; it involves less reagents, reduces waste, and is less-time consuming than traditional methods for OTCs. As such, the procedure connects with the principles of green analytical chemistry. Additionally, good precision (RSD<20%), a very low method quantification limit (MQL) (0.76 ng L(-1) for TBT by using only 10 mL of sample) and excellent linearity (range MQL-20 ng L(-1)) are achieved. Under these conditions, the very restrictive limits for the environmental quality standards (EQS) fixed by the 2013/39/EU Directive are achieved.


Assuntos
Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Compostos Orgânicos de Estanho/análise , Microextração em Fase Sólida , Poluentes Químicos da Água/análise , Água/química , União Europeia
6.
Mar Pollut Bull ; 91(1): 45-53, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25577476

RESUMO

Currently, the lipid content of fish feeds includes high amounts of terrestrial vegetable oils, rich in n-6 fatty acids and poor in n-3 fatty acids. Sinking organic matter in the shape of fragmented pellets and fish faeces could be ingested by the surrounding fauna attracted to the submerged structures of aquaculture facilities or living in natural benthic habitats. Fatty acids contained in feed pellets were used as trophic markers to shed light on the assimilation and incorporation of aquaculture wastes by the invertebrate fauna associated to sea-cages. Eighteen macroinvertebrate species, and zooplankton, seaweeds and sediments were collected from two fish farms, one of which (control) had not been used as such for two years. This study demonstrates that macroinvertebrate fauna present in fouling can take up sinking organic matter from farms. Further research should be directed at assessing the potential implications of aquaculture production for the surrounding ecosystem.


Assuntos
Ração Animal/análise , Aquicultura/métodos , Cadeia Alimentar , Invertebrados/metabolismo , Resíduos/análise , Análise de Variância , Animais , Cromatografia Gasosa , Ecossistema , Ácidos Graxos/análise , Ácidos Graxos/farmacocinética , Fezes/química , Peixes/crescimento & desenvolvimento , Sedimentos Geológicos/química , Mar Mediterrâneo , Espanha , Zooplâncton/metabolismo
7.
Mar Environ Res ; 103: 27-35, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25460059

RESUMO

"Taxocene surrogation" and "taxonomic sufficiency" concepts were applied to the monitoring of soft bottoms macrobenthic assemblages influenced by fish farming following two approaches. Polychaete assemblage evaluation through multivariate analysis and the benthic index BOPA were compared. Six fish farms along the Spanish Mediterranean coast were monitored. Polychaete assemblage provided a suitable picture of the impact gradient, being correlated with total free sulphides. BOPA did not support the impact gradient described by the polychaete assemblage, providing erroneous categorizations. The inclusion of several polychaete families, which were locally identified as indicative of affection to recalculate BOPA, resulted in an improved diagnosis and correlation with the impact gradient. Nevertheless, frequent misclassifications occurred. These results suggest that the structure of polychaete families, sulphides and granulometry conform an appropriate strategy for fish farming monitoring. Biotic indices need to be specifically designed for concrete activities, and regionally validated, because of the environmental plasticity of benthic invertebrates.


Assuntos
Aquicultura , Biodiversidade , Monitoramento Ambiental/métodos , Poliquetos/fisiologia , Sulfetos/análise , Anfípodes/fisiologia , Animais , Organismos Aquáticos/fisiologia , Bass/fisiologia , Sedimentos Geológicos/análise , Mar Mediterrâneo , Análise Multivariada , Dourada/fisiologia , Espanha
8.
Mar Environ Res ; 101: 22-28, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25164018

RESUMO

Nocturnal pelagic swimming is common in the daily activity of peracarids in marine ecosystems. Fish farming facilities in coastal areas constitute an optimal artificial habitat for invertebrates such as amphipods, which can reach high abundance and biomass in fouling communities. Additionally, fish farms may modify the local oceanographic conditions and the distribution of pelagic communities. The aim of this study was to determine if nocturnal abundance and species composition of planktonic amphipod assemblages are affected by fish farm structures, using light traps as collecting method. A total of 809 amphipods belonging to 21 species were captured in farm areas, compared to 42 individuals and 11 species captured in control areas. The most important species contributing to the dissimilarity between farms and controls were the pelagic hyperiid Lestrigonus schizogeneios, the fouling inhabitants Ericthonius punctatus, Jassa marmorata, Stenothoe sp. and Caprella equilibra, and the soft-bottom gammarids Periculodes aequimanus and Urothoe pulchella. The great concentrations of planktonic amphipods at fish farm facilities is a result of the input of individuals from fouling communities attached to aquaculture facilities, along with the potential retention there of hyperiids normally present in the water column and migrant amphipods from soft sediments. Therefore, in addition to the effects of aquaculture on benthic communities, the presence of fish farms induces major changes in planktonic assemblages of invertebrates such as amphipods.


Assuntos
Anfípodes/fisiologia , Aquicultura , Animais , Biodiversidade , Ritmo Circadiano , Ecossistema , Densidade Demográfica , Dinâmica Populacional , Zooplâncton/fisiologia
9.
Chemosphere ; 79(7): 698-705, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20299072

RESUMO

This work proposes a pressurized hot water extraction (PHWE) followed by solid phase microextraction (SPME) and determination by gas chromatography-mass spectrometry method for the analysis of organochlorine pesticides in sediment samples. For SPME, extraction temperature and time, desorption temperature and desorption time, and effect of an organic modifier were studied. For PHWE, parameters such as organic modifier, percentage of organic modifier, temperature, and static extraction time were studied. When these parameters were selected, the figures of merit were calculated in order to assess the performance of the proposed method. Quantitative recoveries (80-115%) and satisfactory precisions were obtained. The detection and quantification limits were between 0.11 and 16 microg kg(-1) and between 0.24 and 22 microg kg(-1), respectively with good linearity between LOQs and 500 microg kg(-1) for most of the studied pesticides. The method was validated by the analysis of a reference marine sediment material (SRM 1944). The obtained results are in excellent agreement with the certificate material. Another sediment reference material (SRM 1941b), with a very low concentration of pesticides was also analyzed with good results. In addition, this method was successfully applied to the analysis of three marine sediment samples. The developed method seems to be a nearly full automated, environmental friendly, sensitive, simple and less-time consuming method. Moreover this method, look for the implementation of the principles of green analytical chemistry and has demonstrated to be suitable for the analysis of organochlorine pesticides at trace levels in environmental matrices as sediment samples.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes do Solo/análise , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/análise , Temperatura Alta , Hidrocarbonetos Clorados/química , Hidrocarbonetos Clorados/isolamento & purificação , Praguicidas/química , Praguicidas/isolamento & purificação , Poluentes do Solo/química , Poluentes do Solo/isolamento & purificação , Microextração em Fase Sólida , Fatores de Tempo , Água/química
10.
J Chromatogr A ; 1207(1-2): 136-45, 2008 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-18760791

RESUMO

This paper presents the development of a programmed temperature vaporization-gas chromatography-tandem mass spectrometry (PTV-GC-MS-MS) method for the determination of PAHs in complex environmental matrices. This method aims at overcoming the current problems in detecting these compounds in matrices such as biota samples. When these matrices are extracted, great amounts of lipid compounds are co-extracted and can interfere with the analysis of PAHs, complicating their identification and quantification. The developed method significantly improves the detection and quantification limits, since PTV-GC-MS-MS can detect compounds at low-ppb level in complex matrices. The instrumental LODs and LOQs achieved lie between 1.04 and 26.9ngl(-1) and 2.06 and 45.4ngl(-1), respectively, and are lower than those calculated in the GC-MS-SIM mode. The LODs and LOQs of the method range between 1.9 and 3.6ngkg(-1) and between 79 and 99ngkg(-1), respectively. The validation of the method were made with a mussel reference material (SRM 2799). The applicability of the method to real mussel samples was also studied. Samples were extracted by means of microwave energy (with acetone:hexane 1:1, v/v) and the extracts were cleaned in a glass column with 22g of alumina. The usefulness of the MS-MS detection was verified. The obtained results were satisfactory, with good accuracy and precision. The proposed PTV-GC-MS-MS method was successfully applied to real mussel samples affected by the Prestige sinking off the Galician coast.


Assuntos
Cromatografia Gasosa/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Espectrometria de Massas em Tandem/métodos , Animais , Bivalves/química , Volatilização
11.
J Chromatogr A ; 1196-1197: 65-72, 2008 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-18501367

RESUMO

A fully automated, environmentally friendly, simple, and sensitive method was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sediment samples. The procedure is based on pressurized hot water extraction (PHWE) followed by solid-phase microextraction (SPME) and determination by gas chromatography-mass spectrometry. For PHWE, parameters such as organic modifier, percentage of organic modifier, temperature, and static extraction time were studied. For SPME, extraction temperature and time, desorption temperature and time, splitless time, ionic strength adjustments, and effect of an organic modifier were studied. When these parameters were selected, the figures of merit were calculated. The detection and quantification limits were between 0.4-15 microg kg(-1) and 1.2-51 microg kg(-1), respectively. The linearity of the method was assessed spiking sediment samples at seven levels of concentration ranged between 2.5 microg kg(-1) and 500 microg kg(-1) for most of the studied PAHs. The method was validated by two concentration levels reference marine sediment materials (SRM 1944 and SRM 1941b). The obtained results are in very good agreement with the certificate materials. The developed method seems to be suitable for the analysis of PAHs at ultratrace levels in environmental matrices as sediment samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Microextração em Fase Sólida/métodos , Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Reprodutibilidade dos Testes , Microextração em Fase Sólida/instrumentação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
12.
Talanta ; 74(5): 1096-103, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18371756

RESUMO

The trace analysis of polycyclic aromatic hydrocarbons (PAHs) in environmental matrices requires highly sensitive and selective methods. The use of large-volume injection in gas chromatography with mass spectrometry detection allows the improvement of the sensitivity. In this work, one of the most popular large-volume injectors, programmed temperature vaporization (PTV)-splitless injection, was optimized to determine 26 alkylated and non-alkylated PAHs at ultratrace levels. The injection conditions that use two different injection volumes, 10 and 25mul, were optimized applying experimental designs. Six experimental factors that could affect the vaporization efficiency were studied. Detection limits for each assayed volume were compared with splitless injection, both in full scan and in SIM mode. An improvement of 50- and 100-fold, for 10 and 25mul, respectively, was achieved for PAHs in comparison with splitless injection. Finally, the method that was optimized for 25mul was applied successfully to the analysis of a certified marine sediment SRM 1941b and a real marine sediment extracted by microwave assisted extraction.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Análise de Injeção de Fluxo , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Temperatura , Volatilização
13.
J Chromatogr A ; 1176(1-2): 48-56, 2007 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-18037429

RESUMO

This article presents a solid-phase microextraction (SPME) procedure to determine 27 parent and alkylated polycyclic aromatic hydrocarbons (PAHs) with diverging polarities and molecular masses in various types of water samples (tap, well, superficial, and seawater). A 65-microm polydimethylsiloxane-divinylbenzene (PDMS/DVB) fiber was used, and parameters affecting the extraction procedures such as extraction temperature and time, desorption temperature and time, splitless time, effect of an organic modifier or ionic adjustment were studied. The linearity and precision of the proposed method were satisfactory. The use of GC-MS determination in the full scan mode, in the selected ion monitoring (SIM) mode, and in the GC-MS-MS mode provided the unequivocal identification and quantification of the target analytes. Moreover, the proposed SPME-GC-MS-MS method, extracting only 18 ml of sample, reached the very restrictive limits fixed by the 2006/0129 EC proposal for a new water directive to be achieved by 2015. The matrix effects were evaluated through the analysis of tap, well, superficial, and seawater. A discussion on different behaviors, a result of the matrix effects, was included. Analytical recoveries were satisfactory in all cases. The novelty of this work consisted in the wide range of analyzed PAHs, the very low detection limits that were reached, the coupling of SPME-GC-MS-MS, and the study of the matrix effect on water samples. With this developed procedure, detection limits between 0.07 and 0.76 ng l(-1) and quantification limits between 0.10 and 0.98 ng l(-1) were obtained with MS-MS detection. Moreover, the analytical recoveries for different aqueous matrices were near 100% in all cases.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Policíclicos/análise , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , União Europeia , Concentração de Íons de Hidrogênio , Concentração Osmolar
14.
J Chromatogr Sci ; 45(7): 369-74, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17725863

RESUMO

In order to propose a versatile method to use in laboratories devoted to environmental analysis, a scheme for the determination of organochlorine pesticides from different solid matrices is evaluated. Pressurized liquid extraction is chosen as the sample preparation technique, followed by the purification of the extract by means of solid-phase extraction with Envi-carb cartridge (100 m(2)/g). Finally, the extracts are analyzed by programmed temperature vaporization (PTV)-gas chromatography (GC)-electron-capture detection and PTV-GC-mass spectrometry. The suitability of the method for the analysis of different matrices is determined by the extraction and analysis of four certified reference materials of solid matrices: CRM 804-050 (soil), SRM 1941b (organics in marine sediment), SRM 1944 (New York/New Jersey waterway sediment) and SRM 1649a (Urban Dust). Good statistical concordance between the results obtained and the certified or reference concentration are observed for most of the analyzed pesticides.


Assuntos
Hidrocarbonetos Clorados/química , Praguicidas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Pressão , Padrões de Referência
15.
Anal Bioanal Chem ; 383(2): 174-81, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16132137

RESUMO

The blank extracts obtained from the pressurized liquid extraction (PLE) of a 11 mL empty cell of ASE 200 were analysed by GC-FID and GC-ECD and many interfering peaks were detected, which could difficult the trace analysis of persistent organic pollutants (i.e. polycyclic aromatic hydrocarbons, aliphatic hydrocarbons and organochlorine pesticides). These interfering compounds were identified as phthalates, silicones and organic acids and their sources were established. A solution to this analytical trouble is a previous extraction step of the empty cell under the same conditions optimised for the sample extraction.


Assuntos
Poluentes Ambientais/análise , Hidrocarbonetos/análise , Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Ácidos Carboxílicos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Clorados/análise , Miniaturização , Ácidos Ftálicos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Silicones/química , Fatores de Tempo
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