| 1. |
|
|
| 2. |
- Illuminati, S., et al.
(författare)
-
In-situ trace metal (Cd, Pb, Cu) speciation along the Po River plume (Northern Adriatic Sea) using submersible systems
- 2019
-
Ingår i: Marine Chemistry. - : Elsevier BV. - 0304-4203. ; 212, s. 47-63
-
Tidskriftsartikel (refereegranskat)abstract
- Information on the distribution and speciation of trace metals is of critical importance for our ability to interpret the links between the bioavailability and uptake of an element, and its biogeochemical cycle in coastal environments. Within the framework of the European Project "In-situ automated Monitoring of Trace metal speciation in Estuaries and Coastal zones in relation with the biogeochemical processes (IMTEC)", the chemical speciation of Cd, Pb and Cu was carried out along the Po River plume in the period 27 October - 2 November 2002. During the cruise, five Voltammetric In-situ Profiling systems and one Multi Physical Chemical Profiler, as well as conventional voltammetric instruments, were successfully applied in order to evaluate the distribution of Cd, Pb and Cu between different fractions (free ion, dynamic, colloidal, dissolved and particulate fractions) and to assess the evolution of these fractions during estuarine mixing and in the water column. Dynamic concentrations were 0.05-0.2 nmol L-1 Cd, 0.02-0.2 nmol L-1 Pb, and 0.15-4.0 nmol L-1 Cu. Cd was mainly present as dynamic fraction (40-100% of the dissolved Cd). High proportions of Pb (similar to 70%) and Cu (similar to 80%) were present as colloids probably of biogenic origin. Principal components analysis reveals a strong influence of the Po River discharge on the spatial and vertical distributions of metal species. Almost all the metal fractions globally decreased following the salinity gradient. Metal concentrations are far below (at least one order of magnitude lower) the Environmental Quality Standard established by the Italian law. However, the Cu dynamic fraction showed concentrations likely to be toxic to sensitive phytoplankton community and to have negative effects on larva development of coastal macroinvertebrate species (toxicity data extracted from literature).
|
|
| 3. |
- Braungardt, C. B., et al.
(författare)
-
Analysis of dissolved metal fractions in coastal waters: An inter-comparison of five voltammetric in situ profiling (VIP) systems
- 2009
-
Ingår i: Marine Chemistry. - : Elsevier BV. - 0304-4203. ; 114:1-2, s. 47-55
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents the results of an inter-comparison exercise undertaken to test the reliability and performance of a voltammetric in situ profiling system (VIP system) and carried out by partners based in Italy, Sweden, Switzerland and the UK. The VIP system was designed to allow in situ simultaneous monitoring of the dynamic fractions (i.e. the maximum potentially bioavailable fractions) of Cu(II). Pb(II) and Cd(II) in natural waters at a frequency of 2-3 analyses h(-1). The four participating groups used the VIP systems under laboratory conditions to determine dissolved concenterations of Cu, Pb and Cd in river, estuarine and coastal water reference materials (SLRS-3/4, SLEW-2/3 and CASS3/4, respectively). The accuracy of the VIP method was comparable to that of established methodologies, including inductively coupled plasma mass spectrometry and voltammetric methods using mercury-electrodes. The VIP systems were also applied to determine the dynamic fractions of the target analytes in freshly collected samples ex situ, as well as in situ in contrasting European marine waters. There was good agreement between the concentrations of the dynamic metal fractions determined in laboratory analyses, and observed during the Simultaneous deployment of up to five VIP instruments for periods of several hours in coastal waters. The simultaneous in situ deployment of two VIP instruments in an estuary showed a consistent analytical performance over several days of continuous operation. The results of this inter-comparison exercise show that the VIP system is a reliable submersible probe for accurate, sensitive and high resolution in situ monitoring of dissolved metal fractions in the picomolar (Cd, Pb) and nanomolar (Cu) concentration ranges. (C) 2009 Elsevier B.V. All rights reserved.
|
|
