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1.
Environ Res ; 161: 399-408, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29197758

RESUMO

In the framework of the FP7 ECsafeSeafood project, 62 seafood samples commercialized in Europe Union from several representative species - mackerel, tuna, salmon, seabream, cod, monkfish, crab, shrimp, octopus, perch and plaice - were analysed for residues of 21 personal care products (PCPs), including 11 UV-filters (UV-Fs) and 10 musk fragrances (musks). PCPs analysis were performed by Quick, Easy, Cheap, Effective Rugged, Safe (QuEChERS), combined with liquid-liquid extraction (LLE) or dispersive solid-phase extraction (dSPE), followed by gas chromatography-tandem mass spectrometry (GC-MS/MS). The results showed the presence in a wide range of samples of nine out of eleven UV-Fs compounds analysed, namely 2-ethylhexyl salicylate (EHS), 2-ethylhexyl,4-methoxycinnamate (EHMC), 4-methylbenzylidenecamphor (4-MBC), benzophenone-1 (BP1), benzophenone-3 (BP3), isoamyl-4-methoxycinnamate (IMC), 2,2'-dihydroxy-4,4'-dimethoxybenzophenone (DHMB), homosalate (HS), and octocrylene (OC), whereas galaxolide (HHCB), galaxolide lactone (HHCB-lactone), and tonalide (AHTN) were the most found musks. The potential risks to human health associated with the exposure to eight of the more prevalent PCPs - EHS, EHMC, 4-MBC, BP1, BP3, IMC, HHCB, and AHTN - through seafood consumption were assessed for consumers from five European countries (Belgium, Ireland, Italy, Portugal and Spain). Results showed that the human exposure to UV-Fs and musks estimated from the concentration values found in seafood and the daily consumption of concerned seafood species, were far below toxicological reference values.


Assuntos
Ácidos Graxos Monoinsaturados , Odorantes , Alimentos Marinhos , Espectrometria de Massas em Tandem , Europa (Continente) , União Europeia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Odorantes/análise , Alimentos Marinhos/análise
2.
Environ Res ; 143(Pt B): 65-71, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25985745

RESUMO

In the last decades, awareness regarding personal care products (PCP), i.e. synthetic organic chemicals frequently used in cosmetic and hygienic products, has become a forward-looking issue, due to their persistency in the environment and their potential multi-organ toxicity in both human and wildlife. Seafood is one of the most significant food commodities in the world and, certainly, one of the most prone to bioaccumulation of PCP, what can consequently lead to human exposure, especially for coastal population, where its consumption is more marked. The aim of this work was to evaluate the co-occurrence of musk fragrances and UV-filters in both seafood and macroalgae collected in different European hotspots (areas with high levels of pollution, highly populated and near wastewater treatment plants). Despite the fact that UV-filters were detected in three different kind of samples (mussel, mullet, and clam), in all cases they were below the limit of quantification. Galaxolide (HHCB) and tonalide (AHTN) were the musk fragrances most frequently detected and quantified in samples from the European hotspots. Cashmeran (DPMI) was also detected in most samples but only quantified in two of them (flounder/herring and mullet). The highest levels of HHCB and AHTN were found in mussels from Po estuary.


Assuntos
Monitoramento Ambiental/métodos , Perfumes/análise , Alimentos Marinhos/análise , Alga Marinha/química , Protetores Solares/análise , Animais , Bivalves/química , Europa (Continente) , Peixes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes , Alimentos Marinhos/normas , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem
3.
Sci Total Environ ; 949: 175128, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39084383

RESUMO

Understanding the impact of plastic and its additives on wild species is crucial as their presence in the environment increases. Polybrominated diphenyl ethers (PBDEs), once used as flame retardants, were restricted due to known toxic effects, but are still detected in the environment. Naturally occurring methoxylated PBDEs (MeO-BDEs) can result from PBDE transformation and may cause similar hazardous effects. Yellow-legged gulls (Larus michahellis, YLG) and Audouin's gulls (Ichthyaetus audouinii, AG) are highly susceptible to plastic additives, due to their distribution, trophic position, and behaviour. In this study, we assessed PBDEs and MeO-BDEs uptake in different tissues and their effects on physiological and reproductive parameters. Findings indicate that, apart from annual differences, adult AG accumulated more MeO-BDEs than YLG in a natural breeding habitat (Deserta), while the latter had lower PBDE levels than YLG breeding in the city of Porto. In relation to chicks, only YLG from Deserta showed higher PBDE concentrations than AG chicks. Individual analysis of each physiological parameter revealed impacts only for adult YLG from Deserta, with neurofunction and immune system inhibition at higher MeO-BDE concentrations. For chicks, AG showed impaired neurofunction, while YLG chicks from Porto exhibited potential genotoxicity effects triggered by higher MeO-BDE levels. Overall health analysis showed activation of antioxidant defences and compromised immune system in YLG adults from Porto due to high values of PBDEs, while chicks from Deserta exhibited inflammation and oxidative stress with high concentrations of MeO-BDEs in the same species. Fertility parameters showed significant differences for sperm counts though suggesting individuals may be able to compensate any exposure effects. This study confirms the widespread presence of plastic-associated compounds and their harmful effects on gulls, particularly on neurofunction, immune system, oxidative balance and fertility, especially due to the presence of MeO-BDEs.


Assuntos
Charadriiformes , Fertilidade , Retardadores de Chama , Éteres Difenil Halogenados , Animais , Charadriiformes/fisiologia , Éteres Difenil Halogenados/toxicidade , Fertilidade/efeitos dos fármacos , Retardadores de Chama/toxicidade , Plásticos/toxicidade , Poluentes Ambientais/toxicidade , Masculino , Reprodução/efeitos dos fármacos , Feminino , Monitoramento Ambiental
4.
Sci Total Environ ; 945: 173815, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38857804

RESUMO

The presence of plastic debris and organo-brominated compounds in the marine environment poses a concern to wildlife. Plastic can absorb and release chemical compounds, making their ingestion potentially harmful, while chemical compounds have become omnipresent, with a tendency to bioaccumulate in the food web. Seabirds are often used as indicators of marine plastic pollution, yet studies on the exposure of tropical communities to plastic contamination are still scarce. In this study we monitored the amounts of plastics in faeces and organo-brominated compounds ingested/assimilated in feathers by adults and chicks of Cape Verde shearwaters and Bulwer's petrels from Cabo Verde. Anthropogenic pollutants, polybrominated diphenyl ethers (PBDEs), and naturally generated methoxylated-PBDEs (MeO-PBDEs) were among the probed compounds. The frequency of plastic debris ingestion was similar in both species' adults and chicks, although, the characteristics of the ingested plastic differed. Frequency and number of microplastics increased throughout the nestling season for chicks from both species. All species and age groups showed the presence of PBDEs and MeO-PBDEs. Among PBDEs, Bulwer's petrels exhibited higher concentrations than Cape Verde shearwaters, and chicks had higher concentration profiles than adults. Specifically, Bulwer's petrel chicks showed higher concentrations than Cape Verde shearwater chicks. On the contrary, Cape Verde shearwater adults exhibited higher occurrence and concentrations of MeO-PBDEs when compared to Cape Verde shearwater chicks. We found no effect of plastic loadings or loadings of organohalogen contaminants on body condition or size, although harmful effects may be hidden or reveal themselves in a medium- to long-term. Feather samples from both adults and chicks were shown to be useful for comparing intraspecific contamination levels and appear suitable for the long-term assessment of organohalogen contaminants in seabirds. Species-specific foraging and feeding strategies are likely the drivers of the observed variation in organochlorine contamination burdens among seabird species.


Assuntos
Monitoramento Ambiental , Éteres Difenil Halogenados , Plásticos , Poluentes Químicos da Água , Animais , Plásticos/análise , Éteres Difenil Halogenados/análise , Poluentes Químicos da Água/análise , Aves/metabolismo , Plumas/química , Masculino , Exposição Ambiental/estatística & dados numéricos
5.
Sci Total Environ ; 912: 168664, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37996016

RESUMO

In this study we found that endocrine disrupting chemicals (EDCs) were omnipresent in a tropical seabird community comprising diverse ecological guilds and distinct foraging and trophic preferences. Because EDCs tend to bioaccumulate within the food web and microplastics can absorb and release harmful chemical compounds, our findings draw attention to the potential threats to wildlife. Thus, the goal of this study was to investigate the role of plastic ingestion, trophic and foraging patterns (δ15N and δ13C) of five tropical seabird species breeding in sympatry, on the exposure to EDCs, namely Polybrominated diphenyl ethers (PBDEs), methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and personal care products (PCPs, e.g., musk fragrances and UV-filters). Results indicated that microplastics occurrence and EDCs detection frequency varied among species. Microplastics occurrence was higher in species with dual and coastal foraging strategies. Preen oil had higher levels of MeO-PBDEs and PCPs, while serum had higher levels of PBDEs. In brown boobies, the correlation between microplastics and ∑PBDEs levels was significant, suggesting that microplastics ingestion is a key PBDEs route. Trophic position (δ15N) plays a key role in PBDEs accumulation, particularly in Bulwer's petrel, which occupies a high trophic position and had more specialized feeding ecology than the other species. MeO-PBDEs were linked to foraging habitat (δ13C), although the link to foraging locations deserves further investigation. Overall, our findings not only fill key gaps in our understanding of seabirds' exposure to microplastics and EDCs, but also provide an essential baseline for future research and monitoring efforts. These findings have broader implications for the marine wildlife conservation and pollution management in sensitive environments, such as the tropical regions off West Africa.


Assuntos
Disruptores Endócrinos , Monitoramento Ambiental , Animais , Éteres Difenil Halogenados/análise , Microplásticos , Plásticos , Animais Selvagens , Aves , Ingestão de Alimentos
6.
Anal Bioanal Chem ; 404(8): 2453-63, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22995997

RESUMO

A new simple and reliable method combining an acetonitrile partitioning extractive procedure followed by dispersive solid-phase cleanup (QuEChERS) with dispersive liquid-liquid microextraction (DLLME) and further gas chromatography mass spectrometry analysis was developed for the simultaneous determination of bisphenol A (BPA) and bisphenol B (BPB) in canned seafood samples. Besides the great enrichment factor provided, the final DLLME extractive step was designed in order to allow the simultaneous acetylation of the compounds required for their gas chromatographic analysis. Tetrachloroethylene was used as extractive solvent, while the acetonitrile extract obtained from QuEChERS was used as dispersive solvent, and anhydride acetic as derivatizing reagent. The main factors influencing QuEChERS and DLLME efficiency including nature of QuEChERS dispersive-SPE sorbents, amount of DLLME extractive and dispersive solvents and nature and amount of derivatizing reagent were evaluated. DLLME procedure provides an effective enrichment of the extract, allowing the required sensitivity even using a single quadropole MS as detector. The optimized method showed to be accurate (>68 % recovery), reproducible (<21 % relative standard deviation) and sensitive for the target analytes (method detection limits of 0.2 µg/kg for BPA and 0.4 µg/kg for BPB). The screening of several canned seafood samples commercialized in Portugal (total = 47) revealed the presence of BPA in more than 83 % of the samples with levels ranging from 1.0 to 99.9 µg/kg, while BPB was found in only one sample at a level of 21.8 µg/kg.


Assuntos
Compostos Benzidrílicos/análise , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Microextração em Fase Líquida/normas , Fenóis/análise , Alimentos Marinhos/análise , Acetonitrilas/química , Embalagem de Alimentos , Portugal , Reprodutibilidade dos Testes , Alimentos Marinhos/normas
7.
Food Res Int ; 135: 109293, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32527484

RESUMO

The presence of bisphenol A (BPA) and eight BPA analogues was investigated in 30 canned meat samples (sausages, pâtés, and whole meals). For that, a previously developed gas chromatography-mass spectrometry (GC-MS) methodology based on a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction followed by dispersive liquid-liquid microextraction (DLLME) with "in situ" acetylation was optimized, namely by the introduction of a novel solid-phase dispersive sorbent. Results showed that all the samples were contaminated with at least one compound from the five bisphenol analogues found (BPA, BPB, BPF, BPAF, and BPZ). Nineteen samples showed the simultaneous presence of BPA and one or more analogues, with a maximum of four different compounds in two of the samples. In half of the samples, the sum of all bisphenols was higher than 50 µg/kg, with a maximum of 236 µg/kg. Regarding human food safety, the estimated daily intake (EDI), target hazard quotient (THQ) and hazard index (HI) assessed were higher than those established by the European Food Safety Authority suggesting hazard risk for human consumers.


Assuntos
Produtos da Carne , Compostos Benzidrílicos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fenóis/análise
8.
J Chromatogr A ; 1216(1): 119-26, 2009 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-19056088

RESUMO

A fast method using low-pressure gas chromatography coupled to mass spectrometry (LP-GC/MS) was implemented and optimized to yield a complete separation of 27 representative pesticides in grapes, musts and wines. Extraction was performed with acetonitrile, applying quick, easy, cheap, effective, rugged and safe (QuEChERS) methodology. Several LP-GC/MS conditions such as column temperature, injection conditions, flow rate, MS conditions and matrix effects were evaluated to achieve the fastest separation with the highest sensitivity in MS detection (selected ion monitoring mode). After optimization, all 27 pesticides were extracted, chromatographically separated and detected in less than 20 min. Acceptable recoveries for nearly all pesticides at three different spiking levels (from 0.04 to 2.5 microg/g) were achieved with good repeatability (from 3 to 21%). Limits of quantification (from 0.02 to 5 microg/g) were lower than the maximum limit of residues, when established for pesticides.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/análise , Vitis/química , Vinho/análise , Acetonitrilas/química , Pressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química , Fatores de Tempo
9.
Artigo em Inglês | MEDLINE | ID: mdl-31374422

RESUMO

Currently, consumption of illicit drugs and pharmaceuticals has increased significantly. Many of these substances are chiral and can be available as racemates or enantiomerically pure. Determination of the enantiomeric fraction (EF) in wastewater is useful for: i) distinguishing between the consumption of prescribed and illicit drugs; ii) identification of possible local of illegal synthesis; iii) illegal discharge of sewage and estimation of illicit drugs and pharmaceuticals consumption by a community (wastewater-based epidemiology). This work describes the development of an indirect method by gas chromatography-mass spectrometry (GC-MS) for enantiomeric quantification of chiral substances namely psychoactive drugs and ß-blockers based on the formation of diastereomers using (R)-(-)-α-methoxy-α-(trifluoromethyl)phenylacetyl chloride ((R)-MTPA-Cl) as chiral derivatization reagent. The developed method presented linearity (R2 > 0.99) for 20 compounds, 9 diastereomer pairs and paroxetine (PAR) and sertraline (SER). Recovery ranged from 80.7 to 114.5% (RSD < 9.1%) and accuracy between 84.6 and 118% (RSD < 9.9%). The limits of detection (LOD) varied from 0.03 and 26.0 ngL-1 and limits of quantification (LOQ) from 0.15 and 104 ngL-1. Results showed the occurrence of amphetamine (AMP), illicit drugs as 3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine (MAMP), alprenolol (ALP), norfluoxetine (NFLX), (SER), metoprolol (MET) and propranolol (PHO) at concentrations ranging from 21.7 ngL-1 (MDMA) to 622 ngL-1 (PHO). Measured concentrations were used to estimate the drug loads of the target chiral substances in a specific population. The EF was determined providing valuable information about the consumption and origin of the target drugs.


Assuntos
Antagonistas Adrenérgicos beta/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Psicotrópicos/química , Antagonistas Adrenérgicos beta/isolamento & purificação , Anfetamina/química , Anfetamina/isolamento & purificação , Limite de Detecção , Metanfetamina/química , Metanfetamina/isolamento & purificação , Psicotrópicos/isolamento & purificação , Esgotos/química , Estereoisomerismo , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
10.
Mar Environ Res ; 138: 110-118, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29709294

RESUMO

The increasing production and consumption of Personal Care Products (PCPs), containing UV-filters and musk fragrances, has led to its widespread presence in the aquatic environment which can cause harmful effects to the aquatic organisms due to its intrinsic toxicity. This study aims to evaluate the degree of contamination of wild mussels along the entire Portuguese coastline, continually exposed in their habitat to different contaminants. For this purpose, approximately 1000 mussel specimens were sampled during one year in seven different locations, along the Portuguese coastline. Simultaneous quantification of five UV-filters and seven musks in mussels was achieved by a Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction procedure combined with dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography with mass spectrometry (GC-MS) analysis. Ten out of the twelve target analytes were found in the analysed samples, highlighting the presence of AHTN (tonalide), EHS (2-ethylhexylsalicylate) and EHMC (2-ethylhexyl 4-methoxycinnamate) in all positive samples (93%). Overall, the results obtained indicate a widespread contamination of wild mussels along Portuguese coastline, all over the year. UV-filters were more frequently detected (90%) than musk fragrances (70%) and also quantified at higher levels, with average total concentrations reaching 1155.8 ng/g (dw) against 397.7 ng/g (dw) respectively. A high correlation was observed between the most densely populated and industrialized locations and the higher levels of musks and UV-filters found. In other hand, lower levels of PCPs were found in protected areas. As expected, an increase in UV-filters levels was observed after the summer, likely due to the intense period of recreational activities.


Assuntos
Bivalves/química , Monitoramento Ambiental , Ácidos Graxos Monoinsaturados/análise , Protetores Solares/análise , Poluentes Químicos da Água/análise , Animais , Cromatografia Gasosa-Espectrometria de Massas , Perfumes , Portugal
11.
Environ Pollut ; 225: 354-360, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28284552

RESUMO

Diclofenac a nonsteroidal anti-inflammatory drug (NSAID) has been confirmed as an emerging contaminant in the aquatic environment. Toxicology studies have revealed that harmful effects may emerge from diclofenac presence not only for human health, but also for marine organisms, which implies its monitoring. To overcome the demanding challenges of diclofenac quantification in biotic aquatic species, a novel method for the determination of diclofenac in mussels (Mytilus galloprovincialis and Mytilus edulis) and macroalgae (Laminaria digitata) using high performance liquid chromatography coupled to tandem mass spectrometry was developed and validated according to the EC Decision 2002/657/EC. Additionally, a study was done about diclofenac contamination in mussels collected from 8 sites along the 1115 miles of coastline in Portugal in 2015. The results suggested that levels in mussels are closely related to the environmental contamination. Therefore, mussels can be a potential bioindicator of diclofenac contamination in the coastal environment.


Assuntos
Diclofenaco/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Animais , Anti-Inflamatórios não Esteroides/análise , Organismos Aquáticos , Humanos , Mytilus/efeitos dos fármacos , Mytilus/fisiologia , Portugal , Frutos do Mar/análise , Espectrometria de Massas em Tandem
12.
J Chromatogr A ; 1414: 10-21, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26341596

RESUMO

A novel multi-residue gas chromatography-mass spectrometry (GC-MS) method was validated for the simultaneous determination of trace levels (ng/L) of 13 UV-filters and bisphenol A (BPA) in wastewater samples. It was based on dispersive liquid-liquid microextraction (DLMME) followed by rapid microwave-assisted silylation of the analytes. Several parameters of both extraction and derivatization steps such as type of extractive and dispersive solvents, solvent volumes, pH, salt addition, time and power of microwave were evaluated to achieve the highest yield and to attain the lowest detection limits. Optimized DLLME consisted in the formation of a cloudy solution promoted by the fast addition to the sample (10mL) of a mixture of tetrachloroethylene (50µL, extraction solvent) in acetone (1mL, dispersive solvent). The sedimented phase obtained was evaporated and further silylated under the irradiation of 600W microwave for 5min, being the derivatization yields similar to those obtained after a conventional heating process for 30min at 75°C. Limits of detection and quantification of the method using real samples were 2ng/L and 10ng/L, respectively. Mean extraction efficiency of 82% for three concentrations were achieved, supporting the accuracy of the method. Intra-day and inter-day repeatability of measurements (expressed as relative standard deviation) were lower than 22%. The method was successfully applied to the determination of UV-filters and BPA in samples collected from 15 wastewater treatment plants (WWTPs) in Portugal. Eight analytes were detected, among which 2-hydroxy-4-methoxybenzophenone, 2-ethylhexyl-4-(dimethylamino)benzoate, octocrylene, and BPA were consistently found in the three seasons of collection.


Assuntos
Compostos Benzidrílicos/análise , Compostos de Organossilício/química , Fenóis/análise , Protetores Solares/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microextração em Fase Líquida/métodos , Micro-Ondas , Solventes
13.
Food Chem ; 182: 143-9, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25842320

RESUMO

A QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was optimized and validated for the simultaneous extraction of 12 trichothecenes (type A and type B) from baby foods, followed by gas chromatography-mass spectrometry (GC-MS) analysis. Using this methodology, limits of detection and quantification ranging from 0.37 to 19.19 µg/kg and 1.24 to 63.33 µg/kg, respectively, were achieved. Mean recoveries between 44% and 135% were obtained and repeatability, expressed as relative standard deviation, was always lower than 29%. A comparison between the developed method and two alternative cleanup procedures (MultiSep and IAC--immunoaffinity columns) was performed, being the advantages and drawbacks of each one presented. The screening of nine commercially available cereal-based baby foods revealed the presence of 4 out of 12 studied trichothecenes: DON (deoxynivalenol), 15AcDON (15-acetyl-deoxynivalenol), T2-Tetrol and NEO (Neosolaniol). DON was the most commonly found, being detected in 4 samples in significant levels (29-270 µg/kg), sometimes exceeding the maximum permitted level. 15AcDON, T2-Tetrol and NEO were found only in one sample each.


Assuntos
Grão Comestível/química , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Alimentos Infantis/análise , Tricotecenos/análise , Cromatografia Gasosa-Espectrometria de Massas/economia , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
J Chromatogr A ; 886(1-2): 183-95, 2000 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-10950286

RESUMO

An accurate and very sensitive method which allows for the simultaneous determination of the diamines (1,3-diaminopropane, putrescine and cadaverine), of the polyamines (spermidine and spermine), and of the aromatic amines (beta-phenylethylamine and tyramine) found in Port wines and corresponding grape juices is presented. Sample clean-up consisted of the extraction of the amines with the ion-pairing reagent bis-2-ethylhexylphosphate dissolved in chloroform followed by a back-extraction with 0.1 M HCl. The hydrochloric extract obtained was dried and the amines were further derivatized with heptafluorobutyric anhydride and analyzed by GC-MS in the selected ion-monitoring mode, with a total run time of 18 min. Under the adopted conditions, the extraction of all the studied compounds was almost complete and the obtained extracts were free of potential interferents present in the samples, namely sugars, and most of the amino acids and polyphenols. Via the use of a set of five selected internal standards (amphetamine, [2H8]putrescine, 1,7-diaminoheptane, norspermidine and norspermine), the data obtained from the linearity, repeatability and recovery experiments were very good for all the compounds assayed. The corresponding limits of detection were invariably below 10 microg l(-1). The method was successfully applied to measure the content of biogenic amines in twelve young and five aged Port wine samples, eleven grape juice samples as well as in ten Portuguese red and white table wines. Results are presented and briefly discussed.


Assuntos
Aminas/análise , Bebidas/análise , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Vinho/análise , Padrões de Referência , Reprodutibilidade dos Testes
15.
J Chromatogr A ; 1040(1): 105-14, 2004 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-15248430

RESUMO

A derivatization method for the analysis of 12 heterocyclic aromatic amines (HAs) in food, by gas chromatography-electron impact mass spectrometry, was developed. The amines are derivatized in a one-step reaction with N-methyl-N-(tert.-butyldimethylsilyl)trifluoroacetamide. The derivatives are characterized by easy-to-interpret mass spectra due to the prominent ion [M-57]+ by loss of a tert.-butyldimethylsilyl group, allowing quantification in the selected-ion monitoring mode at the picogram level. The effect of temperature, time, and reagents on the formation of the derivatives was monitored in detail. Quality parameters were evaluated in the optimum working conditions. This derivatization method is not applicable to the pyridoimidazoles Glu-P-1 and Glu-P-2 and to the beta-carboline harman due to incompletely derivatization. The instability of the imidazolquinoline and imidazoquinoxaline derivatives, requiring their injection on the same working day, is a further drawback. This simple, rapid and accurate derivatization procedure is suitable for routine analysis, as illustrated by the analysis of some common foods.


Assuntos
Aminas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Heterocíclicos/análise , Compostos de Organossilício/química , Reprodutibilidade dos Testes
16.
J Chromatogr A ; 976(1-2): 285-91, 2002 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-12462620

RESUMO

A GC-MS method is described for quantification of 4-(5-)methylimidazole (4MI) in coffee. Although tested, GC-flame ionization detection proved inadequate for this purpose due to the complexity of the coffee matrix. The developed method was based on ion-pair extraction with bis-2-ethylhexylphosphate and derivatization with isobutylchloroformate. Quantification was carried out by the standard addition method using 2-ethylimidazole as internal standard. Reproducibility data from the complete procedure are presented. Mean recoveries were higher than 98%. The method was applied to green and roasted coffee samples from the two most important varieties, arabica and robusta, and to commercial "torrefacto" coffee blends. 4MI was not detected in the green coffee samples analysed and ranged from 0.307 to 1.241 mg/kg in roasted samples.


Assuntos
Café/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Imidazóis/análise , Reprodutibilidade dos Testes
17.
Food Chem Toxicol ; 50(3-4): 1019-26, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22227217

RESUMO

The determination of deoxynivalenol (DON) and its metabolites such as deepoxy-deoxynivalenol (DOM-1) in human urine is complicated due its low levels (ng/mL) and the complexity of the matrix. A gas chromatography-mass spectrometry method was optimized and validated for the confirmation analysis of DON and its metabolites in urine samples using 13C isotopic-labeled DON as internal standard. In the sample preparation the type and amount of ß-glucuronidase for enzymatic hydrolysis was investigated as well as the cleanup procedure, being compared the immunoaffinity column with solid-phase extraction (SPE). As far as we know, SPE C18 cleanup procedure was applied for the first time in the analysis of DON and its metabolites in human urine. Using this analytical methodology the detection and quantification limits achieved ranged from 0.06 to 0.30 ng/mL and from 0.2 to 1.0 ng/mL, respectively. Recoveries were higher than 73% for fortification levels between 25 and 100 ng/mL and repeatability were lower than 13%. The natural occurrence of DON and its metabolites in human urine samples from the north zone of Portugal was studied. Free DON was detected in 15% of the samples whereas total (free+conjugated) DON was detected in 69% of the samples. Deepoxy-deoxynivalenol, 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol were not detected in any of the samples analyzed.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Tricotecenos/urina , Adulto , Cromatografia de Afinidade , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Extração em Fase Sólida
18.
J Chromatogr A ; 1218(43): 7748-57, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21945620

RESUMO

A fast and simple gas chromatography-mass spectrometry (GC-MS) method for determination of forty-one pesticide residues in maize is introduced. The sample preparation involves liquid-liquid partitioning with acetonitrile in presence of anhydrous MgSO(4) and NaCl (QuEChERS) followed by dispersive liquid-liquid microextraction (DLLME) using carbon tetrachloride as extractive solvent and the extract obtained by QuEChERS as dispersive solvent. The main factors influencing DLLME efficiency including extractive solvent type and volume as well as the volume of dispersive solvent were evaluated in this study. The DLLME procedure effectively provides an enrichment of the extract and a cleanup of certain polar matrix components, which can maximize the sensitivity when a single quadrupole MS is used. For validation purposes, recoveries studies were carried out at two concentration levels, yielding recovery rates in the range 70-120% for 82% of the analytes. A good linearity and precision, with relative standard deviations generally below 20% were obtained for all forty-one pesticides. The limits of detection obtained were lower than 19 µg kg(-1) for more than 63% of the analytes. In two of a total of ten samples of maize, residues of lindane, tefluthrin, pirimicarb, folpet and bifenthrin were found, although at levels below the maximum limit established for this kind of samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Resíduos de Praguicidas/análise , Zea mays/química , Acetonitrilas/química , Grão Comestível/química , Análise de Alimentos , Resíduos de Praguicidas/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
J Agric Food Chem ; 59(16): 8742-53, 2011 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-21732693

RESUMO

A simple, reliable, and sensitive gas chromatography-mass spectrometry method for the quantification of volatile and nonvolatile biogenic amines in Port wines and grape juices was developed and evaluated. The method was based on a previously reported two-phase derivatization procedure with isobutyl chloroformate in a toluene medium, which provides a quantitative reaction in 10 min. Following the derivatization step, the excess of reagent was eliminated by treatment with alkaline methanol. The derivatization procedure was performed directly on 1 mL of sample, avoiding any fastidious and time-consuming cleanup extraction steps. The method allows the simultaneous quantification of 22 amines, which can be found in wines: methylamine, dimethylamine, ethylamine, diethylamine, propylamine, isopropylamine, butylamine, isobutylamine, amylamine, isoamylamine, 2-methylbutylamine, hexylamine, pyrrolidine, piperidine, morpholine, 1,3-diaminopropane, putrescine, cadaverine, 1,6-diaminohexane, 2-phenylethylamine, histamine, and tyramine. Because of the fact that histamine and tyramine derivatives are degraded during the isobutyl chloroformate elimination step, the corresponding determination was made after removal of the excess of derivatizing reagent by evaporating an aliquot of the toluene layer obtained after the reaction. The presented method showed excellent analytical characteristics in what linearity, recovery, repeatability, and limit of detections were respected. It was used to assess the concentration of biogenic amines in juice grapes and Tawny and Vintage Port wines with different aging times. On the whole, the total content of amines in Port wines was low. Most of the amines found in wines have their origin in the raw material used for their elaboration, so the Port winemaking process is not prone to the production of this kind of compounds. Total biogenic amine contents have shown a decrease with the aging of both types of Port wines.


Assuntos
Aminas Biogênicas/análise , Formiatos , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Vitis/química , Vinho/análise , Bebidas/análise , Fatores de Tempo
20.
Artigo em Inglês | MEDLINE | ID: mdl-21240700

RESUMO

The purpose of this study was to establish a reliable, cost-effective, fast and simple method to quantify simultaneously both bisphenol A (BPA) and bisphenol B (BPB) in liquid food matrixes such as canned beverages (soft drinks and beers) and powdered infant formula using dispersive liquid-liquid micro-extraction (DLLME) with in-situ derivatisation coupled with heart-cutting gas chromatography-mass spectrometry (GC-MS). For the optimisation of the DLLME procedure different amounts of various extractive and dispersive solvents as well as different amounts of the derivative reagent were compared for their effects on extraction efficiency and yields. The optimised procedure consisted of the injection of a mixture containing tetrachloroethylene (extractant), acetonitrile (dispersant) and acetic anhydride (derivatising reagent) directly into an aliquot of beverage samples or into an aqueous extract of powdered milk samples obtained after a pretreatment of the samples. Given the compatibility of the solvents used, and the low volumes involved, the procedure was easily associated with GC-MS end-point determination, which was accomplished by means of an accurate GC dual column (heart-cutting) technique. Careful optimisation of heart-cutting GC-MS conditions, namely pressure of front and auxiliary inlets, have resulted in a good analytical performance. The linearity of the matrix-matched calibration curves was acceptable, with coefficients of determination (r2) always higher than 0.99. Average recoveries of the BPA and BPB spiked at two concentration levels into beverages and powdered infant formula ranged from 68% to 114% and the relative standard deviation (RSD) was <15%. The limits of detection (LOD) in canned beverages were 5.0 and 2.0 ng l(-1) for BPA and BPB, respectively, whereas LOD in powdered infant formula were 60.0 and 30.0 ng l(-1), respectively. The limits of quantification (LOQ) in canned beverages were 10.0 and 7.0 ng l-1 for BPA and BPB, respectively, whereas LOQ in powdered infant formula were 200.0 and 100.0 ng l(-1), respectively. BPA was detected in 21 of 30 canned beverages (ranging from 0.03 to 4.70 µg l(-1)) and in two of seven powdered infant formula samples (0.23 and 0.40 µg l(-1)) collected in Portugal. BPB was only detected in canned beverages being positive in 15 of 30 samples analysed (ranging from 0.06 to 0.17 µg l(-1)). This is the first report about the presence of BPA and BPB in canned beverages and powdered infant formula in the Portuguese market.


Assuntos
Bebidas/análise , Disruptores Endócrinos/análise , Contaminação de Alimentos , Fórmulas Infantis/química , Fenóis/análise , Métodos Analíticos de Preparação de Amostras , Cerveja/análise , Compostos Benzidrílicos , Calibragem , Bebidas Gaseificadas/análise , Disruptores Endócrinos/química , Disruptores Endócrinos/isolamento & purificação , Embalagem de Alimentos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Indicadores e Reagentes/química , Lactente , Limite de Detecção , Fenóis/química , Fenóis/isolamento & purificação , Portugal , Pós , Reprodutibilidade dos Testes , Solventes/química
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