() Towards an European Harmonisation of Sediment Quality Assessment Methods.

de Deckere, E1, Bakker, J2, De Cooman, W3, Meire, P1, 1 University of Antwerp, Department of Biology, 2610 Wilrijk, Belgium2 RIKZ, The Netherlands3 Flemish Environment Agency, Belgium

ABSTRACT- Water quality monitoring programs and assessment methodologies are being developed in all European countries in function of the implementation of the European Water Framework Directive. The monitoring focuses on a list of chemical priority substances and on biological parameters such as macrophytes, fish and benthic macro-invertebrates. The benthic macro-invertebrates are the only link to the sediment, but both researchers and water managers admit that the role of sediment is an important determining factor for the ecological quality of surface water. Therefore they try to implement sediment quality monitoring and assessment methods into this directive. The European SedNet network enhances this and some prelimnary investigation regarding the methods used in Europe was already done within one of itís working groups. _CR__LF_Based on the sediment quality data bank of the Flemish Environment Agency, containing the triad sediment quality assessment data of more than 1500 sampling locations, a selection was made of five sampling locations within the Schelde river basin, three freshwater, one brackish and one marine. One of the freshwater locations was contaminated with heavy metals, ecotoxicological effects were determined but the in-situ biological quality was good. Strong ecotoxicological effects were determined on the second location but the in-situ biological quality was good and no elevation of the chemical parameters was measured. The third location was a potential reference site. The brackish location is situated on the tidal flats just downstream of the harbour of Antwerp and the marine location is situated on a tidal flat near to the mouth of the Schelde estuary, which might be polluted with endocrine disrupting compounds. Sediment was collected with a Van Veen grab sampler, mixed, stored at 4°C and distributed to nineteen laboratories in nine European countries._CR__LF_Physical parameters such as the organic content, clay content and granulometry were analysed by two laboratories. The chemical compounds measured were arsenic, cadmium, chromium, copper, mercury, lead, nickel, zinc, mineral oils, extractable organohalogens, organic chlorine pesticides, PCBís, PAHís etc. Fourteen laboratories applied their own bioassays. Each laboratory applied itís own bioassays. Both acute and chronic tests were applied on the solid phase, the porewater and on extracts. Several laboratories applied some commonly used bioassays, like microtox, so this can be interpreted as an intercalibration exercise between those laboratories. The biological in-situ quality was characterised based on the present macrobenthic community. The results are interpreted by all laboratories according to their own assessment methods and to their national regulations. Subsequently the results and their interpretations will be used as a step towards a harmonised sediment assessment method.

Key words: sediment quality assessment

Internet Services provided by
Allen Press, Inc. | 810 E. 10th St. | Lawrence, Kansas 66044 USA
e-mail assystant-helpdesk@allenpress.com | Web www.allenpress.com
All content is Copyright © 2004 SETAC