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Twenty years of elemental analysis of marine biota within the German Specimen Bank - a thorough look at the data

Rüdel, Heinz; Fliedner, Annette; Kösters, Jan; Schröter-Kermani, Christa Environ Sci Pollut Res 17 (2010), 5, 1025-1034 As one component of the German ecological environment observation, the Environmental Specimen Bank program was initiated in the mid-1980s. Under the program, representative specimens of marine, fresh water, and terrestrial ecosystems are sampled regularly and archived under chemically stable conditions. An initial characterization of the samples provides data regarding the status quo of the respective ecosystems. The aim of the present publication is to give insight into these real-time monitoring data, which have been generated for the last 10 to 20 years. This is done exemplarily for the heavy metals cadmium (Cd), mercury (Hg), and lead (Pb) in marine specimens of the Baltic and the North Sea. Bladder wrack (Fucus vesiculosus), blue mussel (Mytilus edulis), eelpout (Zoarces viviparus), and eggs of herring gulls (Larus argentatus) were sampled at one location in the Baltic Sea and at two sites in the North Sea (Schleswig-Holstein Wadden Sea and Lower Saxony Wadden Sea). Annual samples were pooled, homogenized, and analyzed for a set of elements. Cd and Pb were quantified after freeze-drying and microwave digestion using inductively coupled plasma-mass spectrometry. Total Hg in freeze-dried samples was determined by atomic absorption spectrometry using a direct mercury analyzer. Time series data covering up to two decades revealed comparable cadmium levels at all three locations. Concentrations in bladder wrack ranged between 0.10 and 0.37 µg/g on a wet weight basis (ww). Respective values for blue mussel and eelpout liver were 0.07–0.29 and 0.01–0.10 µg/g ww. Herring gull eggs were not included in cadmium analyses. Declining trends were observed in North Sea bladder wrack and mussels, eelpout from the Lower Saxony site, and mussels from the Baltic Sea. Upward trends were apparent in eelpout from the Schleswig-Holstein location. Mercury concentrations in Baltic Sea specimens ranged from 1.1–2.7 ng/g ww in bladder wrack to 2.6–5.1, 26–52, and 86–226 ng/g ww in blue mussel, eelpout muscle, and herring gull eggs, respectively. No temporal trends were observed. North Sea bladder wrack had accumulated 5.4–24 ng/g ww Hg. The respective Hg values for blue mussel and eelpout muscle were 19–64 and 73–187 ng/g ww. Highest Hg contents were detected in herring gull eggs (90–1,100 ng/g ww). Declining trends of Hg were observed in herring gull eggs at both North Sea locations and in blue mussels at the Lower Saxony site. Lead concentrations in Baltic Sea specimens were 48–222 ng/g ww in bladder wrack, 85–189 ng/g ww in blue mussel, 2.0–9.5 and 10–42 ng/g ww in eelpout muscle and liver, and 2.7–26 ng/g ww in herring gull eggs. In the North Sea, Pb concentrations were as follows: 68–397 ng/g ww in bladder wrack, 101–507 ng/g ww in blue mussels, 2.6–35 and 5.9–158 ng/g ww in eelpout muscle and liver, and 3.5–55 ng/g ww in herring gull eggs. Highest Pb-levels were found at the Lower Saxony site. Declining Pb-trends were observed in bladder wrack from the Baltic Sea; in bladder wrack and mussel at the Schleswig-Holstein location; and in bladder wrack, mussels, eelpout liver, and herring gull eggs at the Lower Saxony site. During the 10 to 20 years of monitoring, reliable data were obtained which allow a good insight into metal contamination of marine biota. Assessment of the data according to OSPAR criteria (OSPAR 2005) revealed cadmium levels above the derived background concentrations in mussels of all three sites. Mercury levels above background concentrations were found at both North Sea locations, whereas only mussels at the Lower Saxony site had Pb concentrations above the reference value. Archived specimens are available for further analyses and questions which may arise in the future (speciation of elements, metallomics). Electronic supplementary material: The online version of this article (doi:10.1007/s11356-009-0280-8) contains supplementary material, which is available to authorized users. Zur Veröffentlichung | doi:10.1007/s11356-009-0280-8

Extraction of antimony and arsenic from fresh and freeze-dried plant samples as determined by HG-AAS

Krachler, Michael; Emons, Hendrik Fresenius' Journal of Analytical Chemistry 368 (2000), 7, 702 - 707 Six extraction media (acetic acid, EDTA, tetrabutylammonium hydroxide, NaOH, MeOH/H 2 O, acetonitrile/H 2 O) were tested for their ability to extract antimony (Sb) and arsenic (As) from freeze-dried popular leaves, pine shoots and spruce shoots, as well as from a peat matrix. Additionally, the extraction efficiency of Sb and As in fresh and freeze-dried elder leaves and poplar leaves was compared. Total concentrations of Sb and As of aliquots (~220 mg) of the freeze-dried samples were analysed by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) after open vessel digestion with adequate mixtures of nitric, sulfuric, hydrochloric, and perchloric acid. Three reference materials GBW 07602 Bush Branches and Leaves, GBW 07604 Poplar Leaves, and SRM 1575 Pine Needles were analysed with every batch of samples to ensure the accuracy and precision of the applied analytical procedures. The use of hydrofluoric acid in the digestion mixture leads to distinctly lower As values (down to 40%) than actual concentrations in the investigated plant materials. Extraction efficiencies were generally low and lower for Sb than for As. Solutions of 0.66 mol L -1 NaOH liberated highest amounts of Sb with ~10% for popular leaves, and ~19% each for pine shoots and spruce shoots. Distinctly higher concentrations of As in NaOH extracts of popular leaves (22%), pine shoots (32%), and spruce shoots (36%) were quantified. Extraction experiments resulted in yields of 7-9% from fresh elder and popular leaves, respectively, and 8-13% for freeze-dried samples for Sb. The corresponding values for As were 10-35% for the fresh material and 7-37% for the freeze-dried samples. doi:10.1007/s002160000578

Staubniederschlag, Schwermetalle im Staubniederschlag

Der Datenbestand setzt sich aus Analysenergebnissen von Staubniederschlagsuntersuchungen zusammen. Neben dem Staubniederschlag werden die Schwermetalle als Inhaltsstoffe bestimmt.

Cadmium, Quecksilber und Blei im Blut des Menschen

Das Projekt "Cadmium, Quecksilber und Blei im Blut des Menschen" wird vom Umweltbundesamt gefördert und von Untersuchungsstelle für Umwelttoxikologie Schleswig-Holstein durchgeführt. Cd, Hg und Pb werden nach Druckaufschluss durch Atomabsorptionsspektrometrie im Blut des Menschen im Rahmen einer Feldstudie in Schlweswig-Holstein gemessen. Die Auswahl von Probanden erfolgt nach statistischen Kriterien.

Study of reactions between dry rocks and heat exchange fluids

Das Projekt "Study of reactions between dry rocks and heat exchange fluids" wird vom Umweltbundesamt gefördert und von Universität Karlsruhe, Mineralogisches Institut durchgeführt. Objective: To study the reaction between water and rock in order to obtain a better understanding of reactions that happen in a hot dry rock system. General information: reactions between rocks and heat exchange fluid change both the structure and chemical composition of the heated source rocks. Since the surfaces are of foremost interest, the investigations will be mainly concerned with these. The reaction mechanisms will be determined on the basis of measured reaction rates and reaction products. Major and trace elements will be measured in solution as well as surface structures and secondary minerals. Hdo will be used to study the possible replacement of metal cations by h3o+. Solids and liquids will be analysed with sims and mass spectrometry. See also contracts 0001/b, 0079/b, 0002/d, 0057/uk and 0010/f. Advancement: this contract started on 1.10.86 as a continuation of contract 0002/D. Achievements: The aim of the work has been to get closer understanding of water rock interaction at the conditions of hot dry rock energy exploitation by studying its initial reaction. Investigations have been carried out to prove the idea that during the initial phase of the reaction between feldspars and aqueous fluids an exchange between alkali and alkaline earth cations with hydronium ions takes place building a hydronium feldspar at the very outer layers of the mineral. The compositions of the reaction fluids were measured by atomic absorption spectrometry (AAS) and the investigations on the solid samples were carried out by infrared (IR) spectrometry, X-ray diffractometry (XRD), X-ray Guinier camera and secondary ion mass spectrometry (SIMS). Investigations on thin cleaved fragments with the IR method did not show any change of the absorption bands compared to the starting material. XRD investigations on powdered samples gave some evidence for the existence of (D3O) AlSi3O8 by the splitting of the (201) reflection. However these results were not unambiguous. They could not be substanciated with the X-ray Guinier method. SIMS investigations gave a clear direct indication for the incorporation of deuterium in feldspar along with simultaneous depletion of both potassium and aluminium. This result indicates an exchange reaction of deuterium oxide (D3O) for potassium and a disintegration reaction of the (Al, Si)O4 network to occur simultaneously.

Teilprojekt 8

Das Projekt "Teilprojekt 8" wird vom Umweltbundesamt gefördert und von Agraferm Technologies AG durchgeführt. Ziel des Projektes ist es, schnellstmöglich einen Biogasreaktor zur Vergärung von Schlempe im halbtechnischen oder technischen Maßstab auf dem Gelände der CropEnergies in Zeitz zu errichten. An diesem Reaktor werden dann die Versuche zur Charakterisierung der Fermenterbiologie und ihrer metabolischen Regulierung durchgeführt. Am DBFZ und an der TUHH, IUE werden parallel dazu in Laborreaktoren Gärversuche durchgeführt, mit dem Ziel die Methoden für die Versuche im Großmaßstab zu testen. Mit den gewonnenen Erkenntnissen wird der Reaktor so modifiziert, dass der Kohlenstoff-Umsetzungsgrad im Biogasreaktor weiter gesteigert wird. Die durchzuführenden Arbeiten bestehen aus der Erstellung der Planungsunterlagen nach HAOI, dem Abu der Anlage, der anschließenden Inbetriebnahme der Anlage und der wissenschaftlichen Begleitung der Anlage auf dem Schwerpunkt Spurenelemente/Spurenelementanalytik. Die analytischen Methoden sind die Standards zur Düngewertermittlung, Abwassercharakterisierung und der Spurenelementanalytik. (Naßchemische Methoden für N, P, NH4-N; AAS für Metalle; GC für VFA; TS, GV, SS nach ASME)

Geraet fuer die Feststellung von Quecksilber bei der kontinuierlichen Ueberwachung von Emissionen

Das Projekt "Geraet fuer die Feststellung von Quecksilber bei der kontinuierlichen Ueberwachung von Emissionen" wird vom Umweltbundesamt gefördert und von VEREWA Mess- und Regeltechnik durchgeführt. Objective: The project is to develop, manufacture, and test a sampling and measuring device for the continuous determination of mercury and its compounds in the flue gas of incineration plants. In addition, the sampling device will be capable of collecting other heavy metals, such as arsenic, cadmium, chromium, lead, copper, manganese, and nickel. Mercury will be determined photo metrically. The detection limit for Hg is approximately 2 mug/m3. The tests will take place in the industrial environment of a municipal waste incineration plant. The basic principle of the device has been patented. General Information: Mercury (Hg) and its compounds are highly toxic chemicals; emissions from plants, such as waste incinerators, should be prevented as far as possible. Typically, filters are used in order to remove the remaining emissions; for new municipal refuse incineration plants, the EC Directive 89/369 limits Hg emissions after the filters to 200 mug/m3. A device for the continuous control of Hg has been recently developed by the Essen-based VEREWA MESS- UND REGELTECHNIK GMBH. The EC Commission assisted the development and testing of an industrial-environment measuring device at 50 per cent of the project costs. The Hg measuring device consists of a sampling and the measuring part proper. The isokinetic sampling device is capable of sampling not only Hg but other heavy metals as well, such as Cu, Ni, Zn, Sn, Sb, Ba, Pb, Mn. The average Hg retrieval statistics is approximately 93 per cent. The measuring device proper determines the Hg concentration in the dried flue gas by UV AA photometry, the detection limit is approximately 2 mug/m3. The measuring device may be calibrated at any time, allowing for the check of the zero and reference points and of the linearity of the device. Idle time between each taking is in the range of ms; the measured values are shown on the monitor every 2 seconds; the measuring protocols may average the values to convenience. Overall standard deviations are approximately 5 per cent; thus, the device can be used for process control. Further extensions of the measuring device are possible to allow for the determination of heavy metals other than Hg as well. The device has been successfully tested and optimized for several months in the heavy-duty industrial environment of the flue gas stack of a municipal waste incineration plant. Working entirely automatically, the device meets the need for a reference device for the control of emissions from refuse incinerators, as stipulated by the EC Directive 89/369. Achievements: A device for the continuous control mercury has been recently developed. The measuring device consists of a sampling part and the measuring part proper. The isokinetic sampling device is capable of sampling not only mercury but other heavy metals as well, such as copper, nickel, zinc, tin, antimony, barium, lead and manganese. The average mercury retrieval is approximately 93 per cent...

Durchfuehrung von F+E-Arbeiten ueber ein beschleunigtes Pruefverfahren fuer die Auslaugungsbestaendigkeit von Glas - Stufe I

Das Projekt "Durchfuehrung von F+E-Arbeiten ueber ein beschleunigtes Pruefverfahren fuer die Auslaugungsbestaendigkeit von Glas - Stufe I" wird vom Umweltbundesamt gefördert und von Battelle-Institut e.V. durchgeführt. Hochradioaktive Abfaelle (HAW) werden durch Verglasen in eine endlagerfaehige Form gebracht. Korrosionsuntersuchungen sollen die in diesem Konzept enthaltenen Sicherheitsreserven aufzeigen. Hierzu soll ein beschleunigtes Pruefverfahren untersucht werden. Das Verfahren arbeitet mit einer rotierenden Glasscheibe, bei der die Diffusion von Auslaugungsprodukten durch die Grenzschicht kontrolliert variiert werden kann. Die Detektion erfolgt durch Atomabsorption. Die Versuche werden so ausgelegt, dass sie mit vorausgegangenen Untersuchungen des Hahn-Meitner-Instituts korreliert werden koennen. Ziel der Arbeiten ist es, in einer orientierenden Untersuchung zunaechst bei Normaldruck und nur wenig erhoehter Temperatur die Auslaugung in Abhaengigkeit von der Stroemung zu messen und damit die Anwendbarkeit der vorgeschlagenen Methode unter Beweis zu stellen.

Der Quecksilber-, Cadmium- und Bleigehalt in Fischen und anderen Meerestieren im Unterlauf und im Aestuar der Elbe und Weser

Das Projekt "Der Quecksilber-, Cadmium- und Bleigehalt in Fischen und anderen Meerestieren im Unterlauf und im Aestuar der Elbe und Weser" wird vom Umweltbundesamt gefördert und von Staatliches Veterinäruntersuchungsamt für Fische und Fischwaren Cuxhaven durchgeführt. Fische aus Fangplaetzen von Elbe, Weser und Jade werden in den Organen, Haut, Kiemen, Leber, Darm, Nieren, Gonaden und Muskulatur mit Hilfe der Atomabsorption auf Cadmium, Blei und Quecksilber untersucht. Durch die Untersuchungen sollen die Organe ermittelt werden, in denen sich die Schadmetalle anthropogenen Ursprungs akkumulieren. Hierbei sind Abhaengigkeiten der Belastung von Fischarten, den Organen und den Fangplaetzen zu pruefen.

Zur Geochemie des Selens, Thalliums und Schwefels in magmatischen Gesteinen

Das Projekt "Zur Geochemie des Selens, Thalliums und Schwefels in magmatischen Gesteinen" wird vom Umweltbundesamt gefördert und von Universität Karlsruhe (TH), Institut für Petrographie und Geochemie durchgeführt. Das Vorhaben dient zum ersten der Ermittlung des geochemischen Verhaltens von Selen in magmatischen Gesteinen. Darueber hinaus sind die paragenetischen Gehalte an Schwefel, Eisen und Titan zu bestimmen, um Aussagen ueber die Gesetzmaessigkeiten der Se-Gehalte zu erhalten. Der Einfluss von sekundaeren Umwandlungen soll ueber Kalium-, Thallium- und Wassergehalte sowie ueber Fe-II/Fe-III Verhaeltnisse weiter verfolgt werden. Zur Selenspurenbestimmung in geologischem Material wurde eine eigene Methode in Verbindung mit flammenloser Atomabsorptionsspektrometrie entwickelt und mit unabhaengigen Verfahren ueberprueft. Das Analysenverfahren ist sowohl fuer Boeden als auch fuer selendotierte Flachglaeser geeignet.

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