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1.
Chemosphere ; 71(6): 1127-34, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18083211

RESUMO

A survey to estimate the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) emissions of Spanish hot dip galvanising sector was carried out during 2002. This investigation is the first presenting Spanish experimental data related to this industrial sector. Three different matrices: flue gas, ash and filter dust were tested to quantify the PCDD/Fs generated during the galvanising process. The organic source of PCDD/F formation could be from the insufficient degreasing o from inhibitors or additives used in the pickling steps such as quinoline, isoquinoline, 8-methylquinoline or polyether phosphoric acid. Low levels PCDD/Fs were achieved in air emissions when air control devices are used. On the contrary, filter dusts are highly contaminated; indicating that the absence of air control devices would increase the risk of fugitive emissions. Homologue profiles and Principal Component Analysis demonstrate there are differences in the formation mechanisms in the bath zone (ashes) compared to the stack location (filter dusts and air emissions), related to the de novo synthesis and reaction time. The annual PCDD/F emission to the atmosphere for this sector during 2002 has been estimated in 0.023g I-TEQ. The emission factor of plants with air control devices has been calculated at 0.030microg I-TEQ/ton of galvanised steel.


Assuntos
Benzofuranos/análise , Resíduos Industriais/análise , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzofuranos Policlorados , Monitoramento Ambiental , Dibenzodioxinas Policloradas/análise , Análise de Componente Principal , Espanha
2.
Environ Pollut ; 136(3): 493-501, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15862403

RESUMO

Fifteen sediment samples were analysed in order to determine their content of polybrominated diphenylethers (PBDEs), polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs). Samples were collected from several hot spots on the Spanish coast, such as the harbours of Almeria and Tarragona, and the mouths of the Besos and Llobregat rivers in Barcelona. A generic analytical procedure based on Soxhlet extraction followed by an automated cleanup system and gas chromatography-ion trap-mass spectrometry was employed for determining the toxic congeners of PCDDs and PCDFs, as well as dioxin-like PCBs. As regards PBDE determinations, a rapid method based on the use of selective pressurized liquid extraction followed by gas chromatography-negative ion chemical ionization-mass spectrometry was applied. Total toxicity equivalent (WHO-TEQ) values were calculated using the toxicity equivalent factors proposed by WHO for dioxin-like PCBs, PCDDs and PCDFs. WHO-TEQ values ranged from 0.3 to 75 pg/g dry weight (dw), with PCB contribution on the toxicity of the samples between 1 and 84%. Total PBDE levels ranged from 2.7 to 134 ng/g dw, with BDE-209 contribution on the total PBDE contamination between 50 and 99%.


Assuntos
Benzofuranos/análise , Poluentes Ambientais/análise , Sedimentos Geológicos/química , Bifenil Polibromatos/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Cromatografia Gasosa/métodos , Monitoramento Ambiental/métodos , Água Doce , Dibenzodioxinas Policloradas/análise , Espanha
3.
J Mass Spectrom ; 39(10): 1168-75, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15468104

RESUMO

Gas chromatography coupled to quadrupole ion storage mass spectrometry (QISTMS) operating in the non-resonant mode is presented as an innovative approach for the analysis of selected polybrominated diphenyl ethers (PBDEs). Although reductions in complexity and time needed for optimization are achieved in comparison with the resonant option, precise adjustment of the mass spectrometric conditions is required. Differences in isolation and fragmentation patterns of target species with degree of bromination were observed. The reliability of the method was confirmed by using standard solutions through the evaluation of certain quality parameters such as accuracy (92-108%), injection repeatability and reproducibility (coefficient of variation below 10% and 15%, respectively). Detection limits ranged from 62 to 621 fg, providing sensitivity similar to that of negative chemical ionisation (NCIMS) and greater than that of electron ionization mass spectrometry. The applicability of QISTMS method to real samples and matrix effects were evaluated through the analysis of some PBDE congeners in a sewage sludge sample from a Spanish waste-water treatment plant. Comparable results were obtained using QISTMS and NCIMS. According to these observations, QISTMS performed in the non-resonant mode may constitute a low-cost, rapid and reliable alternative to high-resolution devices for the analysis of selected PBDEs in environmental samples.


Assuntos
Éteres/análise , Retardadores de Chama/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Bifenil Polibromatos/análise , Esgotos/química , Saúde Ambiental , Cromatografia Gasosa-Espectrometria de Massas/normas , Reprodutibilidade dos Testes , Eliminação de Resíduos Líquidos
4.
Chemosphere ; 55(11): 1469-75, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15099726

RESUMO

The work aims to characterise PCDDs/Fs in environmental matrices by high resolution gas chromatography coupled to low resolution quadrupole ion-trap mass spectrometry (GC-QITMS/MS). In particular, the study was mainly focused in different environmental samples such as sewage sludge, soils, and sediments and in combustion residues as fly ashes. Previous experiences have already detected and quantified PCDDs/PCDFs in all matrices studied. Moreover, isomer-specific analysis of 2,3,7,8-PCDDs/Fs compounds corroborated good correlation between GC-QITMS/MS and a well-established technique such as high resolution mass spectrometry (HRMS). Finally, QC measures included the participation in intercalibration exercises. Successful results were achieved using GC-QITMS/MS in the analysis of fly ashes, soils and sediment materials. In general, GC-QITMS/MS constitutes an interesting alternative for routine analysis of dioxins in such as matrices.


Assuntos
Benzofuranos/análise , Dioxinas/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas/métodos , Carbono/análise , Cinza de Carvão , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Sedimentos Geológicos/análise , Material Particulado , Esgotos/análise , Solo/análise
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