|
(58-05) Development of a concept for biomarkers: ecological relevance and application in field bioassays. den Besten, Pieter*,1, van der Veen, Martijn1, Rotteveel, Serge1, Kamps, Ria1, de Bruyne, Ellanie1, 1 Institute for Inland Water Management and Waste Water Treatment (RIZA), Lelystad, Netherlands ABSTRACT- There has been controversy about the role, if any, of biomarkers in ecosystem health studies. Biochemical or physiological parameters have to meet several validity criteria before they can be used as markers of exposure or as biomarkers of adverse effects caused by contaminants. The relevance of biomarker reponses for risk assessment on the ecosystem level can be shown (i) by relating the biomarker response to consequences for population dynamics, or (ii) by using information about species-specific sensitivities of the biomarker response. Results will be shown of some studies on the relation between biomarker responses and life history parameters of marine and freshwater invertebrate species. The ecological relevance of the neutral red retention (NRR) test for lysosomal stability and the comet assay for the detection of DNA damage was evaluated for the water flea, Daphnia magna, by comparing the biomarker responses after short- or longterm in vivo exposure to different toxicants with mortality or effects on reproduction. The same approach was followed for the application of biomarkers in the fresh water mussel Dreissena polymorpha. In addition a field exposure of mussels was carried out on 3 locations in the river Meuse and the IJsselmeer (Netherlands). The results indicate that exposure to genotoxic compounds in the water from the Meuse enhances DNA damage. The consequences of these effects are evaluated by comparing comet responses with LC50 values of selected toxicants in laboratory bioassays. Key words: Biomarkers, DNA integrity, Invertebrates |
