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1.
Food Chem ; 156: 73-80, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24629940

RESUMO

Bottled water is packaged in either glass or, to a large extent, in plastic bottles with metallic or plastic caps of different material, shape and colour. Plastic materials are made of one or more monomers and several additives that can eventually migrate into water, either during bottle manufacturing, water filling or storage. The main objective of the present study was to carry out a comprehensive assessment of the quality of the Spanish bottled water market in terms of (i) migration of plastic components or additives during bottling and during storage and (ii) evaluation of the effect of the packaging material and bottle format on the migration potential. The compounds investigated were 5 phthalates, diethylhexyl adipate, alkylphenols and bisphenol A. A set of 362 bottled water samples corresponding to 131 natural mineral waters and spring waters sources and 3 treated waters of several commercial brands were analysed immediately after bottling and after one-year storage (a total of 724 samples). Target compounds were detected in 5.6% of the data values, with diethyl hexyl phthalate and bisphenol A being the most ubiquitous compounds detected. The total daily intake was estimated and a comparison with reference values was indicated.


Assuntos
Água Potável/química , Plásticos/análise , Poluentes da Água/química , Compostos Benzidrílicos/química , Qualidade de Produtos para o Consumidor , Água Potável/efeitos adversos , Embalagem de Alimentos/instrumentação , Cinética , Fenóis/química , Ácidos Ftálicos/química , Espanha
2.
Environ Sci Pollut Res Int ; 21(4): 2846-55, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24146319

RESUMO

This study was aimed to determine the presence of 69 organic contaminants in 77 representative bottled waters collected from 27 countries all over the world. All water samples were contained in polyethylene terephthalate bottles. Target compounds were (1) environmental contaminants (including 13 polycyclic aromatic hydrocarbons (PAHs), 31 pesticides including organochlorine (OCPs), organophosphorus, and pyrethroids; 7 polychlorinated biphenyls (PCBs); and 7 triazines) and (2) plasticizers (including 6 phthalates and 5 other compounds). Samples were analyzed by stir bar sorptive extraction followed by gas chromatography-tandem mass spectrometry. PAHs, OCPs, PCBs, and triazines, which are indicators of groundwater pollution, were not detected in most of the samples, except for naphthalene (0.005-0.202 µg/L, n = 16). On the other hand, plastic components were detected in 77 % of the samples. Most frequently detected compounds were dimethyl phthalate and benzophenone at concentrations of 0.005-0.125 (n = 41) and 0.014-0.921 (n = 32), respectively. Levels detected are discussed in terms of contamination origin and geographical distribution. Target compounds were detected at low concentrations. Results obtained showed the high quality of bottled water in the different countries around the world.


Assuntos
Água Potável/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Clorados/análise , Compostos Organofosforados/análise , Praguicidas/análise , Ácidos Ftálicos/análise , Plastificantes/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Piretrinas/análise , Espectrometria de Massas em Tandem , Triazinas/análise
3.
Food Chem ; 141(1): 373-80, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23768370

RESUMO

This study is aimed to compare Tritan™ and polycarbonate (PC) from a point of view of migration of monomers and additives and toxicological evaluation. Migration assays were performed according with Commission Regulation (UE) No. 10/2011. Samples were incubated at 40°C for three consecutive periods of 10 days. Identification and quantification of the compounds intended to migrate was done using solid phase extraction (SPE) followed by gas chromatography coupled to mass spectrometry (GC-MS) in scan mode. Compounds identified in Tritan™ were 2-phenoxyethanol (2-PE), 4-nonylphenol (4-NP), bisphenol A (BPA), benzylbuthyl phthalate (BBP) and dimethyl isophthalate (DMIP) at levels from 0.027 ± 0.002 to 0.961 ± 0.092 µg/kg, although in the 3rd migration period, BBP and DMIP were the only compounds detected well below the specific migration limit. On the other hand, BPA was the only compound detected in PC polymers at a mean concentration of 0.748 µg/kg. In vitro bioassays for (anti)estrogenic, (anti)androgenic as well as retinoic acid- and vitamin D-like activity were negative for Tritan™ and PC migrates. BPA and DMIP were estrogenic in high concentrations. Exposure of the estrogen-sensitive molluskan sentinel Potamopyrgus antipodarum confirmed the estrogenic activity of BPA in vivo at 30 µg/L.


Assuntos
Embalagem de Alimentos/instrumentação , Plásticos/química , Plásticos/toxicidade , Cimento de Policarboxilato/química , Cimento de Policarboxilato/toxicidade , Poliésteres/química , Poliésteres/toxicidade , Animais , Bioensaio , Cromatografia Gasosa-Espectrometria de Massas , Genes Reporter/efeitos dos fármacos , Temperatura Alta , Cinética , Moluscos/efeitos dos fármacos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Leveduras/efeitos dos fármacos , Leveduras/genética
4.
Environ Sci Pollut Res Int ; 19(8): 3339-49, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22421799

RESUMO

BACKGROUND, AIM AND SCOPE: Groundwaters and source waters are exposed to environmental pollution due to agricultural and industrial activities that can enhance the leaching of organic contaminants. Pesticides are among the most widely studied compounds in groundwater, but little information is available on the presence of phthalates, alkylphenols and bisphenol A. These compounds are used in pesticide formulations and represent an emerging family of contaminants due to their widespread environmental presence and endocrine-disrupting properties. Knowledge on the occurrence of contaminants in source waters intended for bottling is important for sanitary and regulatory purposes. So the aim of the present study was to evaluate the presence of phthalates, alkylphenols, triazines, chloroacetamides and bisphenol A throughout 131 Spanish water sources intended for bottling. Waters studied were spring waters and boreholes which have a protection diameter to minimize environmental contamination. MATERIALS AND METHODS: Waters were solid-phase extracted (SPE) and analysed by gas chromatography coupled to mass spectrometry (GC-MS). Quality control analysis comprising recovery studies, blank analysis and limits of detection were performed. RESULTS AND DISCUSSION: Using SPE and GC-MS, the 21 target compounds were satisfactorily recovered (77-124 %) and limits of quantification were between 0.0004 and 0.029 µg/L for pesticides, while for alkylphenols, bisphenol A and phthalates the limits of quantification were from 0.0018 µg/L for octylphenol to 0.970 µg/L for bis(2-ethylhexyl) phthalate. Among the 21 compounds analysed, only 9 were detected at levels between 0.002 and 1.115 µg/L. Compounds identified were triazine herbicides, alkylphenols, bisphenol A and two phthalates. Spring waters or shallow boreholes were the sites more vulnerable to contaminants. Eighty-five percent of the samples did not contain any of the target compounds. CONCLUSIONS: Target compounds were detected in a very low concentration and only in very few samples. This indicates the good quality of source waters intended for bottling and the effectiveness of the protection measures adopted in Spain. None of the samples analysed exceeded the maximum legislated levels for drinking water both in Spain and in the European Union.


Assuntos
Água Potável/química , Herbicidas/análise , Fenóis/análise , Ácidos Ftálicos/análise , Poluentes Químicos da Água/análise , Compostos Benzidrílicos , Disruptores Endócrinos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos , Espanha
5.
Plant Mol Biol ; 50(2): 249-59, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12175017

RESUMO

The Arabidopsis gene Atrab28 has been shown to be expressed during late embryogenesis. The pattern of expression of Atrab28 mRNA and protein during embryo development is largely restricted to provascular tissues of mature embryos, and in contrast to the maize Rab28 homologue it cannot be induced by ABA and dehydration in vegetative tissues. Here, we have studied the subcellular location of Atrab28 protein and the effect of its over-expression in transgenic Arabidopsis plants. The Atrab28 protein was mainly detected in the nucleus and nucleolus of cells from mature embryos. In frame fusion of Atrab28 to the reporter green fluorescent protein (GFP) directed the GFP to the nucleus in transgenic Arabidopsis and in transiently transformed onion cells. Analysis of chimeric constructs identified an N-terminal region of 60 amino acids containing a five amino acid motif QPKRP that was necessary for targeting GFP to the nucleus. These results indicate that Atrab28 protein is targeted to the nuclear compartments by a new nuclear localization signal (NLS). Transgenic Arabidopsis plants, with gain of Atrab28 function, showed faster germination rates under either standard or salt and osmotic stress conditions. Moreover, improved cation toxicity tolerance was also observed not only during germination but also in seedlings. These results suggest a role of Atrab28 in the ion cell balance during late embryogenesis and germination.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas , Proteínas de Plantas/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Sítios de Ligação/genética , Transporte Biológico , Cátions/toxicidade , Núcleo Celular/metabolismo , Expressão Gênica , Germinação/genética , Germinação/fisiologia , Proteínas de Fluorescência Verde , Immunoblotting , Cloreto de Lítio/toxicidade , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Sinais de Localização Nuclear/genética , Cebolas/citologia , Cebolas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sementes/metabolismo
6.
Physiol Plant ; 114(2): 281-287, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11903975

RESUMO

Arginine decarboxylase (ADC; EC 4.1.1.19) is a key enzyme in one of the two possible ways to synthesize putrescine (Put) in plants. In previous work (Masgrau et al. 1997), we observed an altered phenotype (growth inhibition, leaf chlorosis and necrosis) in tobacco transgenic plants (Nicotiana tabacum L. var. Wisconsin-38) containing the oat ADC cDNA under the control of a tetracycline inducible promoter, the severity of which was correlated with Put content. Now we have analysed the T2 generation of a selected transgenic line (line 52), which in previous generations was characterized by presenting a moderate increase in ADC activity and polyamine levels, but no phenotype alterations. Studying two selected individuals, one with a high expression level of the transgene and the other with a moderate expression level, we demonstrate that only the one with increased polyamine content displays the altered (toxic) phenotype. The possible causes of toxicity have been analysed. The results suggest that either Put or its oxidation products, via diamine oxidase (DAO; EC 1.4.3.6), are the responsible factors for the deleterious effects observed in the transgenic plants.

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