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1.
J Hazard Mater ; 148(1-2): 199-209, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17382467

RESUMO

In a long-term program polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) as well as dioxin-like polychlorinated biphenyls (DL-PCBs) were analyzed in the muscle tissue of eels (Anguilla anguilla), bream (Abramis brama), European chub (Leuciscus cephalus) and ide (Leuciscus idus) from the river Elbe and its tributaries Mulde and Saale. The variation of the PCDD/F and DL-PCB concentrations in all fish samples is very large, whereby the DL-PCBs predominate in comparison to the PCDD/Fs. In the eels, the concentrations (pg WHO-TEQ/g ww) for the PCDD/Fs lie in the range of 0.48-22 and for the DL-PCBs between 8.5 and 59. In the whitefish, the concentration range is 0.48-12 for the PCDD/Fs and 1.2-14 for the DL-PCBs. Statistical analysis using relative congener patterns for PCDD/Fs allow spatial correlations to be examined for sub-populations of eels and whitefish. The results are compared to the maximum levels laid down in the European Commission Regulation (EC) No. 466/2001 and the action levels of the European Commission Recommendation 2006/88/EC. Eels caught directly after the major flood in August 2002 as well as eels near Hamburg (years 1996 and 1998) show high concentration peaks. Compared to the eels whitefish is less contaminated with PCDD/Fs and DL-PCBs.


Assuntos
Monitoramento Ambiental/métodos , Resíduos Industriais/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Rios/química , Poluentes Químicos da Água/análise , Animais , Peixes , Alemanha , Dibenzodioxinas Policloradas/análise
2.
Sci Total Environ ; 364(1-3): 96-112, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16199077

RESUMO

Meadow soils, feeding-stuffs and foodstuffs from the alluvial plain of the river Elbe were analyzed in respect of PCDD/Fs, DL-PCBs and mercury with a view to assessing the consequences of the extreme flood of August 2002. The PCDD/F concentrations in the soils range from 3 to 2100 ng WHO-TEQ/kg dm, and for the DL-PCBs the range was 0.32 to 28 ng WHO-TEQ/kg dm. On the basis of established threshold values >40% of the areas are only fit for restricted usage. Mercury concentrations range from 0.11 to 17 mg/kg dm, whereby the action value of 2 mg/kg dm is exceeded in about 50% of the soil samples. A cumulative memory effect from past floods rather than a recent contamination from August 2002 is documented. Soils taken from behind broken dykes showed significantly lower concentrations. Grass, hay and grass silage originating from pasture land in Lower Saxony were taken before and immediately after the flooding. PCDD/Fs range from 0.29 to 16 ng WHO-TEQ/kg, the maximum permitted value of 0.75 ng WHO-TEQ/kg was exceeded in about 50% of the samples. Muscle-tissue from cattle, sheep, lamb and a roe deer as well as untreated milk from individual cows returned values ranging from 0.76 to 5.9 pg WHO-PCDD/F-TEQ/g fat, and 10% of the samples returned values higher than the permitted maximum of 3 pg WHO-PCDD/F-TEQ/g fat. The action value of 2 pg WHO-PCDD/F-TEQ/g fat was exceeded in 33% of the samples. No direct connection between these results and the effects of the flood could be established. A major input path for PCDD/Fs is the tributary Mulde, which discharges contaminated sediments from its catchment area into the Elbe.


Assuntos
Ração Animal/análise , Contaminação de Alimentos , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Animais , Animais Domésticos , Benzofuranos/análise , Dibenzofuranos Policlorados , Desastres , Europa (Continente) , Mercúrio/análise , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/análise , Rios/química
3.
Water Sci Technol ; 50(5): 309-16, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15497862

RESUMO

As a result of extreme precipitation in August 2002 major flooding occurred in the catchment area of the rivers Elbe, Vltava (Moldau) and Mulde. Pollutants from industrial sites and from municipal sewage treatment works (STW) entered the Elbe and led to a serious pollution problem in the river. PCDD/F concentrations (in pg WHO-TEQ/g dw) in SPM ranged from 7-150, in sediments from 3-140; the "safe sediment value" of 20 was exceeded in 46% of the samples. 24 eels showed a wide concentration variation for these contaminants. The WHO-PCDD/F+PCB-TEQ values lay in the range from 11-56 pg/g ww, whereby the WHO-PCB-TEQ values were several times higher than the WHO-PCDD/F-TEQ values. The maximum permitted value of 4 pg WHO-PCDD/F/g ww (EU Directive No. 2375/2001) was reached or exceeded in 54% of the individuals. A statistical analysis using data from SPM and sediment samples showed that in the Czech river section the flooding activated a contamination source in the vicinity of the Spolana works. The influence of the tributary Mulde could be clearly demonstrated. Only a major clean-up of the contaminated sites in Bitterfeld can lead to a mid to long term improvement in respect of PCDD/F and dioxin-like PCB input into the Elbe.


Assuntos
Benzofuranos/análise , Peixes/sangue , Dibenzodioxinas Policloradas/análogos & derivados , Dibenzodioxinas Policloradas/análise , Poluentes Químicos da Água/análise , Animais , Interpretação Estatística de Dados , Dibenzofuranos Policlorados , Europa (Continente) , Peixes/metabolismo , Geografia , Sedimentos Geológicos/química , Bifenilos Policlorados/análise , Rios/química , Fatores de Tempo
4.
Chemosphere ; 57(2): 107-26, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15294435

RESUMO

Medicinal drugs were found to be ubiquitous in the river Elbe, its tributary the river Saale and in other tributaries at their points of entry into the Elbe. The distribution of concentration peaks along the investigated river stretches provides an indication that they are mainly due to the emission of treated waste water from municipal sewage treatment works. This leads to the conclusion that medicinal substances can be regarded as faecal indicators for water pollution caused by human activity. The main substances found in the Elbe in 1998 were diclofenac, ibuprofen and carbamazepine as well as various antibiotics and lipid regulators in the concentration range of <20-140 ng/l. The more thorough investigations carried out in 1999 and 2000 show that in addition to the drugs (phenazone, isopropyl-phenazone and paracetamol) metabolite concentrations contributed significantly to the total concentration of pharmaceuticals in the Elbe. The metamizole metabolites N-acetyl-4-aminoantipyrine (AAA) and N-formyl-4-aminoantipyrine (FAA) were found in concentrations from <20 to 939 ng/l. A multivariate statistical analysis revealed a high correlation in respect of the distribution of persistent substances. The metoprolol distribution throughout the Saale demonstrated that the tributaries cause either an increase (Weisse Elster, Unstrut, Ilm) or a reduction (Wipper, Bode) in the concentration, depending on the respective load of waste water. Wide scale sampling in Saxony during 2002 showed the ubiquitous occurrence of carbamazepine in surface waters. The ecotoxicological effects of this contamination cannot be assessed at present. This is due to the fact that no legal framework in respect of these medicinal drugs for human consumption has been established and therefore little research and no risk assessment has been carried out. Therefore it is urgently necessary to include at least the quantitatively most significant substances in the new assessment concept of the EC White Paper.


Assuntos
Monitoramento Ambiental , Preparações Farmacêuticas/análise , Rios/química , Esgotos/química , Poluentes Químicos da Água/análise , Análise por Conglomerados , República Tcheca , Indústria Farmacêutica , Geografia , Alemanha , Humanos , Preparações Farmacêuticas/química , Preparações Farmacêuticas/classificação , Estações do Ano
5.
Chemosphere ; 45(3): 245-59, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11592413

RESUMO

The xenoestrogens Bisphenol A (BPA), p-alkylphenols and p-alkylphenol ethoxylates were determined in water samples of the North Sea, the Elbe river, and its tributaries Schwarze Elster, Mulde, Saale and the Weisse Elster. The sampling sites of the Elbe river reached from Schmilka at the German-Czech border to Cuxhaven at the estuary. Samples of the North Sea were taken in the German Bight. Additionally, freshly deposed sediments of the River Elbe and its tributaries were analyzed. Partitioning coefficients of these compounds for the distribution between suspended particulate matter (SPM) and the aqueous phase were calculated for samples of the River Elbe at sampling site Geesthacht. The analytical procedure consisted of liquid-liquid extractions of the acidified water samples using dichloromethane. Sediments and SPM samples were extracted by Accelerated Solvent Extraction with n-hexane/acetone. Following a clean-up by HPLC, the analytes were derivatized with heptafluorobutyric acid anhydride and quantified using GC-MSD. The concentration ranges of the compounds analyzed in water samples of the Elbe river were as follows (in ng l(-1)): BPA 9-776, alkylphenols 10-221 and alkylphenol ethoxylates 18-302. In sediment samples the concentrations were (in microg kg(-1) dry mass): BPA 66-343, alkylphenols 17-1378 and alkylphenol ethoxylates 30-1797. In samples of the North Sea the concentrations were generally about 1 order of magnitude lower. As shown by the concentration profiles following the River Elbe into the North Sea, the Elbe river must be considered as a major pollution source for the North Sea concerning the compounds analyzed. The SPM/water-partitioning coefficients calculated (mean values) amounted to: BPA 4.50, alkylphenols 5.52-5.58 and alkylphenol ethoxylates 5.60-6.38. A comparison of the results with data from other surface waters showed that concentrations of these xenoestrogens in the River Elbe and its tributaries were relatively low. The evaluation of the data based on the lowest observable effect concentration (LOEC) for alkylphenols (endpoint: vitellogenin synthesis in male trout) indicated that the concentrations were well below the effectivity threshold.


Assuntos
Estrogênios não Esteroides/análise , Fenóis/análise , Poluentes Químicos da Água/análise , Compostos Benzidrílicos , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Sedimentos Geológicos/química , Alemanha , Mar do Norte , Xenobióticos/análise
6.
Sci Total Environ ; 281(1-3): 153-63, 2001 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-11778948

RESUMO

Excessive amounts of heavy metals (e.g. Zn, Cu, Mn, Cr) are accumulated in river bottom sediments (RBS), being available to humans and animals along food chains. Increased exposure of mammals to certain metals (Cr, Cu) induces immunosuppresion, due to DNA damage and decreased survival of lymphoid cells. By contrast, excess of Zn and Cd causes inhibition of apoptosis thus suggesting increased survival of genetically mutated cells and higher cancer risks in exposed populations. Rat thymic lymphocytes represent a well-established model for apoptosis testing. The primary goal of our study was to assess the degree of apoptosis modulation with a number of RBS extracts differing in their metal contents. A series of freshly deposited RBS was collected at nine sampling stations along the Elbe River. All sediments were rich in Fe, Mn and Zn. The contents of Cu, Cr, Ni, Cd, Hg, Pb and As were much lower and interrelated. The short-term cytotoxicity of aqueous sediment extracts was assessed, using the following criteria: total cell counts; incidence of apoptosis and necrosis (morphological detection by fluorescent microscopy); and nuclear chromatin decay (by DNA flow cytometry). RBS extracts produced both apoptosis and necrosis of thymocytes. High contents of zinc and other heavy metals in the samples correlated with decreased thymocyte apoptosis (r= -0.543 to -0.608, P <0.01). The rates of thymocyte damage showed a distinct dependence on the time and region of sampling. Apoptosis modulation was also tested with pure salts of Mn(II), Zn(II), Cu(II), Cr(III) and Cd(II), at the test concentrations of 1, 10 and 100 microM. Cu(II) and Cr(III) proved to induce marked dose-related apoptosis, whereas Zn(II) ions caused significant suppression of apoptosis. These effects were similar to those trends observed with metal-rich sediments. In the present study. DNA flow cytometry proved to be a less sensitive index of cell death than morphological assay of apoptosis and/or necrosis. In summary, inhibition of lymphocyte apoptosis by RBS extracts and pure metals is associated with excess of zinc and, probably, cadmium. The proposed model of lymphoid cell apoptosis is a promising tool for screening cytotoxic effects of complex environmental samples.


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/efeitos adversos , Dano ao DNA , Timo/citologia , Zinco/efeitos adversos , Animais , Técnicas de Cultura de Células , Cromatina , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Monitoramento Ambiental/métodos , Citometria de Fluxo , Cadeia Alimentar , Sedimentos Geológicos/química , Humanos , Necrose , Ratos , Timo/patologia , Testes de Toxicidade
7.
Fresenius J Anal Chem ; 366(2): 196-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11225927

RESUMO

A monitor is described which provides the on-line determination of mercury in river water at concentrations from 20 to 1000 ng/L. The measurement includes an on-line digestion with Br-/BrO3- and UV-radiation. Each determination is controlled by an on-line addition of 50 and 100 ng/L mercury carried out by pre-dilution of a 500 and 1000 ng/L stock solution using sequential injection analysis (SIA). One cycle of analysis takes 20 min and results in nine signals. A five days stand-alone operation has been performed successfully. Details are also published at web page: "http/www.rzbd.fh-hamburg.de/-prmercol".


Assuntos
Monitoramento Ambiental/instrumentação , Água Doce/química , Mercúrio/análise , Poluentes Químicos da Água/análise , Alemanha
8.
Chemosphere ; 37(9-12): 1987-2002, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9828324

RESUMO

With several multivariate statistical methods a classification of dioxin data has been tried. As a main result one significant source of dioxin in the river Elbe, in the harbour of Hamburg as well as in soils of the flooding areas of the river Elbe could be identified: the dioxin contaminated region Bitterfeld. Our statistical results indicate that the dioxin contamination in the Bitterfeld region was caused partly by metallurgy processes and not only by chemical production.


Assuntos
Benzofuranos/análise , Dibenzodioxinas Policloradas/análogos & derivados , Poluentes Químicos da Água/análise , Indústria Química , Monitoramento Ambiental , Sedimentos Geológicos/química , Alemanha , Metalurgia , Análise Multivariada , Dibenzodioxinas Policloradas/análise , Poluentes do Solo/metabolismo
9.
Muscle Nerve ; 13(1): 56-62, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2183045

RESUMO

Duchenne de Boulogne was among the first to investigate neuromuscular diseases. He stimulated muscle and nerve with moistened surface electrodes, thereby avoiding tissue necrosis. Technique and self-designed equipment are discussed in his first major work de l'électrisation localisée. During his 30 years of practice, he examined several hundred patients with poliomyelitis. With electrodiagnostic evaluation, he focused on "electrocontractility," the intensity of muscle contraction elicited by electrical stimulation. Based on his electrophysiologic findings, Duchenne suggested that the responsible lesion resided within the spinal cord. He used electrical stimulation for treatment and recognized prognostic features.


Assuntos
Poliomielite/história , Eletrodiagnóstico/história , História do Século XIX , Humanos , Paris , Poliomielite/diagnóstico
10.
Drug Intell Clin Pharm ; 22(11): 889-90, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3234256

RESUMO

This report details the management of status epilepticus with high-dose lorazepam in a 14-year-old patient who was receiving oral clonazepam, ethosuximide, and phenobarbital for an intractable seizure disorder. Although respiratory depression is a frequently cited potential complication of therapy, it did not occur in this patient despite an extraordinarily high total dose of lorazepam, possibly because of tolerance associated with benzodiazepine-receptor down-regulation in this patient's chronic clonazepam therapy. Aggressive dosing of a benzodiazepine may be required for patients receiving chronic benzodiazepine therapy.


Assuntos
Lorazepam/uso terapêutico , Estado Epiléptico/tratamento farmacológico , Adolescente , Humanos , Lorazepam/administração & dosagem , Masculino , Estado Epiléptico/fisiopatologia
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