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1.
J Environ Radioact ; 101(5): 414-20, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20346550

RESUMEN

Two former uranium mines and a uranium reprocessing factory in the city of Aktau, Kazakhstan, may represent a risk of contaminating the surrounding areas by uranium and its daughter elements. One of the possible fingerprinting tools for studying the environmental contamination is using plant samples, collected in the surroundings of this city in 2007 and 2008. The distribution pattern of environmental pollution by uranium and thorium was evaluated by determining the thorium and uranium concentrations in plant samples (Artemisia austriaca) from the city of Aktau and comparing these results with those obtained for the same species of plants from an unpolluted area (town of Kurchatov). The determination of the uranium and thorium concentrations in different parts of A. austriaca plants collected from the analyzed areas demonstrated that the main contamination of the flora in areas surrounding the city of Aktau was due to dust transported by the wind from the uranium mines. The results obtained demonstrate that all the areas surrounding Aktau have a higher pollution level due to thorium and uranium than the control area (Kurchatov). A few "hot points" with high concentrations of uranium and thorium were found near the uranium reprocessing factory and the uranium mines.


Asunto(s)
Monitoreo del Ambiente/métodos , Torio/análisis , Uranio/análisis , Kazajstán , Espectrometría de Masas , Plantas/química
2.
Pharmazie ; 59(11): 824-7, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15587579

RESUMEN

Monitoring both the trace element and main element content of drugs forms part of their quality control. Chromium, selenium and molybdenum were determined in therapeutic diet samples by inductively coupled plasma/mass spectrometry (ICP-MS) and electrothermal atomic absorption spectrometry (ET-AAS). Samples were digested by high pressure microwave digestion or by ashing in oven. ICP-MS measurements have demonstrated that the chromium determination in liquid therapeutic diet should be estimated on the basis of 53Cr. In solid samples in some cases the value for Cr was elevated in comparison with the Cr content found by ET-AAS. The content of selenium can be determined on the basis of 77Se or 82Se after appropriate interference correction. Molybdenum content was determined on the basis of 95Mo. Control measurements were made by ET-AAS. For quality assurance purposes some of the samples were analyzed by a control laboratory.


Asunto(s)
Cromo/análisis , Dieta , Alimentos Formulados/análisis , Molibdeno/análisis , Selenio/análisis , Chlorophyta/química , Polvos , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Atómica , Nicotiana/química
3.
Pharmazie ; 58(7): 480-2, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12889531

RESUMEN

As, Ca, Cd, Cu, Fe, Mg, Mn, Pb and Zn were determined by ICP-MS and ET-AAS in preparations made from peppermint and nettle leaves after microwave high pressure digestion with nitric acid. In preparation from nettle leaves the Ca content was more than three times higher than in preparations made from peppermint leaves. Only very small differences (less than 10%) were observed for all the other elements. In all the samples investigated the content of inorganic elements were below the WHO limit (where existing). Variation coefficients ranged from 0.68% to 10.5% for ICP-MS measurements and from 1.48% to 10.0% for ET-ASS.


Asunto(s)
Mentha piperita/química , Urtica dioica/química , Calibración , Elementos Químicos , Espectrometría de Masas , Microondas , Hojas de la Planta/química , Espectrofotometría Atómica
4.
Fresenius J Anal Chem ; 370(4): 434-7, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11495070

RESUMEN

A potentiometric stripping analysis (PSA) method has been developed and checked for the fast and reliable determination of antimony in vegetation samples of Cistus ladanifer from a mining area in Badajoz, Southwest Spain. The method, modified from previous PSA methods for Sb in environmental samples, is based on dry ashing of the homogenized leaves, dissolution in hydrochloric acid, and PSA analysis on a mercury film plated on to a glassy carbon disk electrode. The influence of experimental variables such as the deposition potential, the deposition time, the signal stability and the calibration parameters, has been investigated. The method has been compared with an independent technique (instrumental neutron activation analysis) by analysis of standards and reference materials and comparison of the results. As a result of automation of the PSA equipment, the proposed method enables unattended analysis of 20 digested samples in a total time of 2 h, thus providing a useful tool for Sb monitoring of a large number of samples.


Asunto(s)
Antimonio/análisis , Contaminantes Ambientales/análisis , Minería , Plantas/química , Calibración , Electrodos , Indicadores y Reactivos , Mercurio/química , Oxidantes/análisis , Hojas de la Planta/química , Potenciometría
5.
Sci Total Environ ; 255(1-3): 75-84, 2000 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-10898396

RESUMEN

Various vegetables (broad beans, corn, potato, alfalfa and onion) were sampled in northern Chile, Antofagasta Region. They are the basis of human nutrition in this region and of great relevance to human health. This region is characterized by volcanic events (eruptions, thermal springs, etc.). Most of the vegetables cultivated in this area enter the local markets for a population of approximately 4000 people, whose ancestors were mainly atacameños and quechuas (local indigenous people). The cadmium and lead in these foods was determined by differential pulse anodic stripping voltammetry (DPASV). Results indicate that the highest concentration of Pb and Cd are in the potato skin, while the edible part of the potatoes contained a lower concentration of these metals. The INAA analyses of As in the vegetables from Socaire and Talabre, two towns located close to active volcanoes (e.g. Lascar), show a very high As content: 1850 microg/kg in corn (Socaire) and 860 microg/kg in potatoes (+ skin) (Talabre). These values exceed the National Standard for arsenic (500 microg/kg) by approximately 400% and 180%, respectively. In general, the data show a concentration of Pb greater than Cd with the potential for some vegetables to accumulate heavy metals, The values, expressed in fresh weight, vary from 0.2 to 40 microg/g for Cd and from 0.6 to 94 microg/g for Pb. These concentration intervals, except that of arsenic, are within the recommended standards in the Food Sanitary Regulation (Decree 977), which, expressed as fresh weight, must be equal to or smaller than 500 microg/kg for Pb. There is no legal standard for Cd.


Asunto(s)
Arsénico/análisis , Cadmio/análisis , Monitoreo del Ambiente , Plomo/análisis , Verduras/química , Chile , Dieta , Electroquímica , Monitoreo del Ambiente/legislación & jurisprudencia , Monitoreo del Ambiente/estadística & datos numéricos , Humanos , Indígenas Sudamericanos
6.
Sci Total Environ ; 255(1-3): 85-95, 2000 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-10898397

RESUMEN

The pre-Andes water in the region of Antofagasta is the main drinking and irrigation water source for approximately 3000 Atacameña (indigenous) people. The concentration for soluble elements (filtration in field through a 0.45-microm filter) was: Cd < 0.1 ng/ml; Pb < 0.5 ng/ml; and Zn and Cu between 1 and 10 ng/ml. In particulate material the concentrations were: for Cd < 0.1 ng/ml; for Pb < 0.3 ng/ml; and for Zn and Cu less than 1 ng/ml. The total content of these elements is far below the international recommendations (WHO) and the national standards (N. Ch. 1333 mod. 1987 and 409-1 of 1984). On the other hand, in some rivers a very high arsenic concentration was found (up to 3000 ng/ml) which exceed more than 50 times the national standard. In order to verify the analytical results, inter-laboratory and comparison with different determination methods have been done.


Asunto(s)
Monitoreo del Ambiente , Agua Dulce/química , Metales Pesados/análisis , Oligoelementos/análisis , Contaminación Química del Agua/análisis , Abastecimiento de Agua , Chile , Electroquímica , Monitoreo del Ambiente/legislación & jurisprudencia , Monitoreo del Ambiente/estadística & datos numéricos , Humanos , Indígenas Sudamericanos , Reproducibilidad de los Resultados , Abastecimiento de Agua/análisis , Abastecimiento de Agua/legislación & jurisprudencia , Abastecimiento de Agua/estadística & datos numéricos
7.
Zentralbl Hyg Umweltmed ; 202(2-4): 165-78, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10507126

RESUMEN

Patients with health problems attributed to environmental factors such as chemical pollutants and electromagnetic fields often do not present evidence of an environmental aetiology of their symptoms. It has been postulated, that their problems are due to disorders diagnosed by other medical disciplines, especially allergology and psychiatry. Our study was designed to subject these patients to a comprehensive diagnostic program involving several medical disciplines in order to achieve diagnoses appropriate to explain the patients' symptoms. Fifty patients consecutively referred to the department of environmental medicine in the university hospital of Aachen, Germany, were submitted to the following examinations: (i) environmental medicine (history, clinical examination, biological and/or ambient monitoring for environmental agents); (ii) allergological examination (history, clinical examination, skin tests); (iii) psychiatric examination (psychopathological examination, psychometric and neuropsychological testing). In addition, the patients were examined in other hospital departments according to the symptoms presented. The findings were discussed in case conferences attended by the physicians involved in order to achieve individual diagnoses. The numbers of patients to whom diagnoses were given by different medical disciplines are as follows: psychiatry (32 patients), dermatology (4), allergology (2), neurology (2), rheumatology (2), gynaecology (1), haematology (1). The most frequent mental disorders diagnosed by the psychiatrists were somatoform disorders (19), followed by schizophreniform and delusion disorders (7). In spite of extensive diagnostic efforts, patients with health problems attributed to the environment usually do not present sufficient evidence of an environmental aetiology of their symptoms. On the other hand the symptoms often meet the diagnostic criteria of other diseases, especially of mental disorders.


Asunto(s)
Enfermedades Ambientales/diagnóstico , Enfermedades Ambientales/psicología , Medicina Ambiental , Grupo de Atención al Paciente , Trastornos Somatomorfos/diagnóstico , Adulto , Contaminantes Ambientales/efectos adversos , Femenino , Alemania , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Trastornos Somatomorfos/psicología
8.
Sci Total Environ ; 229(3): 209-15, 1999 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10418170

RESUMEN

Copper, lead, cadmium, and zinc were determined by anodic stripping voltammetry after sample digestion and potentiometric stripping analysis was used for Pb and Cd determination in original samples. Selenium was determined by cathodic stripping voltammetry or hydride generation AAS. Element levels found in the whole blood sample in a group of 82 people are for Cd: 0.98 +/- 0.94 ng/ml; for Pb: 46.7 +/- 28.6 ng/ml; for Cu: 1.07 +/- 0.12 micrograms/ml; for Zn: 6.95 +/- 1.08 micrograms/ml, and for Se: 116 +/- 25 ng/ml. Analytical data have been correlated to age, sex, smokers or non-smokers, drinking and food habits.


Asunto(s)
Metales Pesados/sangre , Oligoelementos/sangre , Población Urbana , Adulto , Factores de Edad , Anciano , Cadmio/sangre , Cobre/sangre , Femenino , Humanos , Plomo/sangre , Masculino , Persona de Mediana Edad , Potenciometría , Factores Sexuales , Fumar , España , Zinc/sangre
9.
J Environ Monit ; 1(1): 97-102, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11529088

RESUMEN

Algae are increasingly used for the purpose of environmental biomonitoring, for instance in the long-term program of the Federal Environmental Specimen Bank of Germany. Therefore, for the studies presented here, freeze-dried samples of Fucus vesiculosus collected from the North Sea shores were analyzed for a broad range of elements by instrumental neutron activation analysis (INAA), while inductively coupled plasma atomic emission spectrometry (ICP-AES) and mass spectrometry (ICP-MS) were carried out on digests. The entire analytical procedures, including field sampling, cleaning of material, sample handling, determination of blanks and instrumental parameters, are described. Certified reference materials analyzed in parallel with real samples and intermethod comparisons were used for assuring the accuracy of the analytical data. Reproducibility of INAA measurements was between 4 and 6% depending on the element considered. Possible sources of uncertainty and variation of the contaminant origins are discussed. Boundary conditions for the performance of algae sampling within environmental monitoring programs and the application of this marine bioindicator for the purpose of controlling time-dependent and local differences in element patterns are presented.


Asunto(s)
Monitoreo del Ambiente/métodos , Eucariontes/química , Metales Pesados/análisis , Criopreservación , Monitoreo del Ambiente/normas , Espectrometría de Masas/métodos , Espectrometría de Masas/normas , Neutrones , Control de Calidad , Manejo de Especímenes , Espectrofotometría/métodos , Espectrofotometría/normas
10.
Sci Total Environ ; 207(1): 29-42, 1997 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-9397597

RESUMEN

In order to evaluate the influence of geographically varying marine ecosystem properties on the uptake of trace elements in bioindicators, samples were taken of seaweed (Fucus vesiculosus) and common mussel (Mytilus edulis) along the North Sea and Baltic Sea coast. Seasonal variations of the bioindicator status were minimized by sampling within 1 month. Ecosystem properties considered were the geographical position, the salinity and the concentrations of the macroelements Ca, Fe, K, Mg, Na, P and S in the bioindicators. Trace elements studied were As, Cd, Co, Cu, Hg, Mn, Ni, Pb and Zn. Factor analysis of the concentration patterns in the bioindicators and of salinity as a function of location confirmed the influence of the geographically varying salinity on the biological uptake of macroelements and trace elements. This influence of salinity was higher in the case of seaweed than in the case of mussel. Comparison of the geographical courses of the macroelement and trace-element concentrations by cluster analysis revealed corresponding courses for As and Hg in both bioindicators. All other elements showed different courses in seaweed and mussel. Subsequent cluster analysis comparing locations with respect to the macroelement or trace-element concentration patterns in the bioindicators, indicated a clear separation of North and Baltic Sea locations. However, the trace-element concentration patterns provided a regionally less distinctive ecosystem arrangement than those of the macroelement ones. The results of the cluster analysis were verified by discriminant analysis forming groups of locations with respect to geographical position and salinity. Results of discriminant analysis demonstrated, both for seaweed and for mussel as bioindicators, that the location groups formed according to the macroelement concentration patterns corresponded well with the geographical regions in the order of salinity. On the other hand, location groups based on the trace-element concentration patterns again showed a modified less distinctive ecosystem arrangement than the location groups based on macroelement concentration patterns. This confirms modified conditions for the uptake of trace elements in seaweed or mussel in comparison to the uptake of macroelements.


Asunto(s)
Bivalvos/metabolismo , Ecosistema , Algas Marinas/metabolismo , Oligoelementos/farmacocinética , Animales , Bivalvos/química , Manganeso/análisis , Manganeso/metabolismo , Manganeso/farmacocinética , Modelos Estadísticos , Análisis Multivariante , Mar del Norte , Potasio/análisis , Potasio/metabolismo , Algas Marinas/química , Sodio/análisis , Sodio/metabolismo , Estadística como Asunto/métodos , Oligoelementos/análisis , Oligoelementos/metabolismo , Zinc/análisis , Zinc/metabolismo , Zinc/farmacocinética
11.
Chemosphere ; 34(9-10): 2049-58, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9159904

RESUMEN

Results of more than ten years of experience in the determination of metals in mussels and algae collected in the North Sea and the Baltic Sea are presented. The various elements determined here are Hg, As, Se, Cd, Pb, Cu, Na, K, S, P, Zn, Mn, Fe, Sr, Ca, Ba, Mg, Tl, Ni, Co using techniques such as cold vapor AAS, INAA, hydride generation AAS, electrothermal AAS, ICP-AES, IDMS and stripping voltammetry. The results indicate the occurrence of three groups of elements with respect to long-term tendencies of their concentrations. In the first group, the concentrations in both mussels and algae varied in the same manner; in the second group no change was observed in either matrix while in the third group, the concentrations of elements changed in an opposite manner.


Asunto(s)
Bivalvos/química , Ecosistema , Elementos Químicos , Monitoreo del Ambiente/métodos , Phaeophyceae/química , Contaminantes Químicos del Agua/análisis , Animales , Modelos Lineales , Océanos y Mares , Especificidad de la Especie , Factores de Tiempo
12.
Chemosphere ; 34(9-10): 2143-51, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9159910

RESUMEN

Since 1985 the common mussel Mytulis edulis has been collected, characterized and stored within the framework of the German Environmental Specimen Bank program. Selected results about the determination of various pollutants such as heavy metals, polycyclic aromatic hydrocarbons and chlorinated hydrocarbons are presented. Particular emphasis is given to the comparison of seasonal variations with respect to different environmental contaminants and their correlations depending on sampling location and time.


Asunto(s)
Bancos de Muestras Biológicas , Bivalvos/química , Monitoreo del Ambiente/métodos , Estaciones del Año , Contaminantes Químicos del Agua/análisis , Animales , Alemania , Hidrocarburos Clorados/análisis , Océanos y Mares , Hidrocarburos Policíclicos Aromáticos/análisis , Factores de Tiempo , Oligoelementos/análisis
13.
Chemosphere ; 34(9-10): 2133-42, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9159909

RESUMEN

Several elements and metal species were analyzed in eel-pout or viviparous blenny (Zoarces viviparus). The analytical data demonstrate that fish muscle is a suitable bioindicator for mercury (Hg) and arsenic (As). About 90% of the total Hg content is present in the fish muscle in the form of methyl mercury. Due to higher concentration levels, the liver is more useful for monitoring Pb and TI. No biomagnification of some trace elements, such as Cd, Ni or Co, were observed in eel-pout. More information is necessary to decide about the use of eel-pout for long-time monitoring programs.


Asunto(s)
Bancos de Muestras Biológicas , Elementos Químicos , Monitoreo del Ambiente/métodos , Peces/metabolismo , Metales/análisis , Contaminantes Químicos del Agua/análisis , Envejecimiento/metabolismo , Animales , Sistemas de Computación , Femenino , Alemania , Hígado/química , Masculino , Músculos/química , Océanos y Mares , Factores de Tiempo
14.
Chemosphere ; 34(9-10): 2227-36, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9159915

RESUMEN

As part of the program of the German Environmental Specimen Bank (ESB), precipitation is sampled on a weekly basis from eight sites in different ecosystems throughout Germany. The samples are analyzed for Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, and SO4(2-) using ion chromatography with conductometrie detection Mn, Co, Ni, Cu, Zn, Cd, Pb, and Tl are determined by ICP-MS. In addition, pH and conductivity of the samples are measured. In this paper, the weekly and annual deposition in 1994 is compared for the different sampling sites and with literature data.


Asunto(s)
Bancos de Muestras Biológicas/tendencias , Ecosistema , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Precipitación Química , Conductividad Eléctrica , Alemania , Concentración de Iones de Hidrógeno , Factores de Tiempo
15.
Sci Total Environ ; 139-140: 365-86, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8272841

RESUMEN

Analyses of selected tissues from the Alaska Marine Mammal Tissue Archival Project (AMMTAP) have provided comprehensive information related to levels of 36 trace elements and methyl-mercury in marine mammal tissues. Liver, kidney and muscle tissues from two northern fur seals, four ringed seals and six belukha whales were analyzed. The bulk of the investigated tissues and additional tissues from a total of 65 marine mammals are banked in the AMMTAP. The results are compared to literature values for trace element concentrations in marine mammal tissues and their relevance to environmental studies is discussed.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Phocidae , Oligoelementos/análisis , Ballenas , Alaska , Animales , Femenino , Riñón/química , Hígado/química , Masculino , Músculos/química , Análisis de Activación de Neutrones , Especificidad de Órganos , Especificidad de la Especie , Manejo de Especímenes , Bancos de Tejidos
16.
Sci Total Environ ; 139-140: 403-10, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8272845

RESUMEN

The National Biomonitoring Specimen Bank at the National Institute of Standards and Technology applies a variety of techniques for extensive characterization of banked samples. To determine a large number of trace elements in small samples at low levels, instrumental neutron activation analysis has been combined with voltammetry. The two methods produce high quality data for thirty pollutant and biological trace elements. Results on archived specimens of human livers and intercomparisons of the two methods are reported.


Asunto(s)
Monitoreo del Ambiente , Hígado/química , Bancos de Tejidos , Oligoelementos/análisis , Animales , Electroquímica/métodos , Humanos , Mamíferos , Análisis de Activación de Neutrones/métodos , Agua de Mar , Manejo de Especímenes
17.
Clin Chem ; 38(10): 1995-2001, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1394983

RESUMEN

The commercially available equipment for potentiometric stripping analysis (PSA) was tested for routine lead and cadmium determination in whole-blood samples. In contrast to anodic stripping voltammetry, PSA is not subject to background interferences from organic electroactive constituents in the sample or to the presence of dissolved oxygen (i.e., oxygen removal is not necessary). To determine lead and cadmium by PSA, it is sufficient to dilute the blood sample with an appropriate supporting electrolyte (0.5 mol/L HCl). The detection limit changes with deposition time and volume of blood sample used. For 1 mL of blood and a 1-min deposition time, the detection limit is 1 microgram/L for both elements. If the deposition time increases to 10 min, cadmium can be determined at its normal concentration in blood (the detection limit is improved to < 0.1 microgram/L). Procedures for routine determination of lead and cadmium in whole blood are presented.


Asunto(s)
Cadmio/sangre , Plomo/sangre , Potenciometría/métodos , Humanos , Concentración de Iones de Hidrógeno , Octoxinol , Polietilenglicoles , Potenciometría/normas , Potenciometría/estadística & datos numéricos , Control de Calidad
18.
Sci Total Environ ; 60: 1-16, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3563481

RESUMEN

A reliable procedure for the determination of the trace metals Cd, Cu, Ni, Pb and Zn in liquid and solid environmental samples by an advanced voltammetric method has been developed. A convenient method of sample pretreatment is wet digestion in a HNO3/HClO4 mixture. The simultaneous voltammetric determination of Cd, Cu, Pb and Zn is made at pH 2 by differential pulse anodic stripping voltammetry (DPASV); the simultaneous determination of Ni and Co at pH 9 after adsorptive accumulation of the respective complex with dimethylglyoxime at the electrode is made by adsorption differential pulse voltammetry (ADPV). The particular advantages of the voltametric approach in food control for heavy metals are high sensitivity, good precision and accuracy, the possibilities for the simultaneous determination of groups of metals and low cost instrumentation.


Asunto(s)
Análisis de los Alimentos , Hígado/análisis , Plantas/análisis , Oligoelementos/análisis , Animales , Bovinos , Electroquímica , Alimentos Infantiles/análisis
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