1 / 25

Copper speciation in the Stockholm Archipelago

Acknowledgements. Hans Borg G

khuong
Télécharger la présentation

Copper speciation in the Stockholm Archipelago

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


    2. Work done at UC Santa Cruz campus located at the Northern end of the Monterey Bay which has the deepest submarine canyon (even deeper than the Grand Canyon) But I will not talk about Monterey today but instead will talk about the San Francisco Bay and estuary. Which unlike Monterey is very shallow with an average depth of only about 5 meters and drained by the Sacramento and San Joaquin rivers. And here we see the Golden Gate Bridge probably one of the most famous features of San Francisco and the Bay area Work done at UC Santa Cruz campus located at the Northern end of the Monterey Bay which has the deepest submarine canyon (even deeper than the Grand Canyon) But I will not talk about Monterey today but instead will talk about the San Francisco Bay and estuary. Which unlike Monterey is very shallow with an average depth of only about 5 meters and drained by the Sacramento and San Joaquin rivers. And here we see the Golden Gate Bridge probably one of the most famous features of San Francisco and the Bay area

    3. Ability to measure metal concentrations in natural waters significantly advanced in last 56-60 years largely due to improvements in instrumental analytical techniques especially AAS and IPC-OES/MS Trace metals in natural waters routinely being measured at low ng/ml level (and even lower with appropriate care) As detection limits dropped, workers became increasingly aware of the problems of contamination during both sample collection and analysis. Clean sampling and analytical protocols together with use of clean room facilities to minimize atmospheric contamination essential for ultra trace analysis are now in widespread use Over the last 1520 years, the combined use of clean techniques and sensitive instrumental methods has led to the generation of reliable data on metal distributions in the worlds oceanic, estuarine and (some) freshwater systems. As soon as ecotoxicologists availed themselves of these developments in trace analysis, it became clear that metal toxicity was poorly correlated with total metal concentrations. This stimulated an interest in measuring metal speciation, with the goal of determining the elusive metal fraction that correlated with toxicity. Ability to measure metal concentrations in natural waters significantly advanced in last 56-60 years largely due to improvements in instrumental analytical techniques especially AAS and IPC-OES/MS Trace metals in natural waters routinely being measured at low ng/ml level (and even lower with appropriate care) As detection limits dropped, workers became increasingly aware of the problems of contamination during both sample collection and analysis. Clean sampling and analytical protocols together with use of clean room facilities to minimize atmospheric contamination essential for ultra trace analysis are now in widespread use Over the last 1520 years, the combined use of clean techniques and sensitive instrumental methods has led to the generation of reliable data on metal distributions in the worlds oceanic, estuarine and (some) freshwater systems. As soon as ecotoxicologists availed themselves of these developments in trace analysis, it became clear that metal toxicity was poorly correlated with total metal concentrations. This stimulated an interest in measuring metal speciation, with the goal of determining the elusive metal fraction that correlated with toxicity.

    6. Fig. 2. This early data set illustrates the FIAM. The results highlight the effect of copper complexation by EDTA, a strong Cu-complexing agent, on the doseresponse curve for a dinoflagellate exposed to Cu. Of the three sets of curves that are shown, the middle set, labeled No EDTA indicates the response (% mortality, measured as % non-motile cells) plotted vs. total dissolved copper, in the absence of EDTA. The set labeled EDTA Added shows how the curves are displaced to the right when EDTA is present. Note how a single concentration may be associated with a wide range in organism response (e.g. ;10100% at log10 Cus3 or Cus1000 mgyl), depending on whether or not EDTA is present. Finally, the response data converge to a consistent relationship when plotted vs. free ion activity, Cu2q (the four curves plotted to the left). (Adapted from Anderson and Morel, 1978.)Fig. 2. This early data set illustrates the FIAM. The results highlight the effect of copper complexation by EDTA, a strong Cu-complexing agent, on the doseresponse curve for a dinoflagellate exposed to Cu. Of the three sets of curves that are shown, the middle set, labeled No EDTA indicates the response (% mortality, measured as % non-motile cells) plotted vs. total dissolved copper, in the absence of EDTA. The set labeled EDTA Added shows how the curves are displaced to the right when EDTA is present. Note how a single concentration may be associated with a wide range in organism response (e.g. ;10100% at log10 Cus3 or Cus1000 mgyl), depending on whether or not EDTA is present. Finally, the response data converge to a consistent relationship when plotted vs. free ion activity, Cu2q (the four curves plotted to the left). (Adapted from Anderson and Morel, 1978.)

    10. Synthetic Chelators

    11. (A) Release of complexing agents and metal-ligand complexes from marine phytoplankton: CdX-phytochelatin Cd complex released by diatoms, CuY peptide complexes of Cu released by coccolithophorids; CuZ, unidentified complexes released by synechococcus; sid, siderophore released by cyanobacteria; L, unidentified Co complexing agent released by prochlorococcus (B) Redox cycling of Mn and Fe via photochemical and biochemical processes. Diatoms extracellularly reduce Fe(III) ligand complexes during Fe uptake. Heterotrophic marine bacteria oxidize Mn(II), forming a MnO2 casing around the cell (A) Release of complexing agents and metal-ligand complexes from marine phytoplankton: CdX-phytochelatin Cd complex released by diatoms, CuY peptide complexes of Cu released by coccolithophorids; CuZ, unidentified complexes released by synechococcus; sid, siderophore released by cyanobacteria; L, unidentified Co complexing agent released by prochlorococcus (B) Redox cycling of Mn and Fe via photochemical and biochemical processes. Diatoms extracellularly reduce Fe(III) ligand complexes during Fe uptake. Heterotrophic marine bacteria oxidize Mn(II), forming a MnO2 casing around the cell

    17. A comparison with a previous investigation from the same area in 1993 shows that the levels of copper and zinc have increased since then in all types of samples and at all sites for which comparisons are possible. In the water samples the copper concentrations have generally doubled, while zinc concentrations have gone up with up to 6.5 times (conclusion from KEMI 2004 study)A comparison with a previous investigation from the same area in 1993 shows that the levels of copper and zinc have increased since then in all types of samples and at all sites for which comparisons are possible. In the water samples the copper concentrations have generally doubled, while zinc concentrations have gone up with up to 6.5 times (conclusion from KEMI 2004 study)

More Related