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2K - Sediment Assays (TUP/137) Experiences with sediment toxicity testing methods in Hamburg Harbour. Maaß, Vera1, Meyer-Nehls, Regina2, 1 Free and Hanseatic City of Hamburg, State Ministry for Economic and Labour Affairs, Department of Port and River Engenieering, Hamburg, Germany2 , Hamburg, Germany ABSTRACT- Sediment toxicity testing methods were checked for practicability in the assessment of sediment quality in Hamburg Harbour. A set of biological tests, both sediment elutriate tests and whole sediment tests, have been realised since 1994. Following test organisms were used: sediment elutriate tests with the green alga Desmodesmus subspicatus and Pseudokirchneriella subkapitata, the cladocerans Daphnia magna, and the bacteria Vibrio fisheri (Microtox) whole sediment tests with the bacteria Bacillus cereus and Arthrobacter globiformis. Sediment samples were taken in the total area of Hamburg Harbour. The sediments were characterised by means of both biological tests and several chemical and physical methods. Additionally, measurements of dissolved concentrations of pollutants and nutrients of sediment samples were carried out. Results of chemical and physical analyses were correlated with data from biological tests. In the period of investigations, the toxicity of sediments of Hamburg Harbour does not appear to be attributable to the content of tested contaminants. For example, at a number of sampling stations the toxic response to various test organisms increased during 1999-2001. In contrast, the concentrations of tested contaminants showed a decreasing tendency in most of the sediment samples of Hamburg Harbour. These investigations confirmed again that the toxicity of sediment is a complex result of contaminant-particle interaction and, furthermore, strongly depends on the sensibility of the test species. In order to assess the quality of sediments by means of biological testing methods, the understanding of processes controlling bioavailability of pollutants is necessary. Additionally, identification of new contaminants should proceed. Key words: sediment contamination, sediment toxicity |
