EurOCEAN 2000 - Vlaams Instituut voor de Zee

TRACE METAL MONOTORING IN SURFACE MARINE WATERS
AND ESTUARIES
MEMOSEA
INTRODUCTION
E. Vander Donckt
The need for monitoring of heavy-metals in marine environments is well established. The
requirements for this have been specified by the Oslo-Paris convention. Analytical techniques
with the necessary sensitivity and accuracy are available, but often they are time consuming
off-line methods.
The major drawback of present analytical tools is that they are often fragile and their
application in stand-alone systems is difficult. This is due to their size and weight (ICP-
MS/GFAAS), operational difficulties and their sensitivity to matrix components present in sea
water. In addition, the manual sample handling procedures involved in metal determination
using present tools do not always preserve sample integrity.
Optical techniques based on molecular spectroscopy offer distinct advantages for reason of
simplicity and absence of physical contact between the detection system and the analytes. In
particular, luminescence methods (fluorescence, phosphorescence, chemiluminescence) offer
potential advantages in ion determination: high sensitivity, ease of automation and
straightforward application of fibre optics based remote sensing.
The project is aiming at the development of a marine water optical sensor for metals detection
and at the development of dedicated analytical procedures.
Three of the partners were selected for their complementary experience in analytical and
luminescence techniques. Each of them establishes an analytical method pertinent to the metals
to be determined. Cu, Fe, Mn and Co are to be addressed by chemiluminescence methods; Hg
and Pb by steady and time dependent phosphorescence (ms time-range); Cd and Zn by steady
and time-dependent fluorescence (ns time-range).
One of the partners has to design a steady and time-dependent luminometer based on
commercially available excitation, detection and optical parts. This generic equipment is to be
adapted to the requirements of all the partners in the project. It is thus a further step towards a
multi-element, multi-technique monitor.
A heavy metals preconcentration system is to be designed and constructed by the fourth
partner. This preconcentration equipment becomes an integral part of the shared luminescence
detector at the end of the project.
RESULTS
This project synopsis reports the state of the work, two years after its beginning.
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