W9 AM Biomonitoring
Wednesday, 16 November 2005: 8:00 AM - 11:40 AM in 339-340

(VOE-1117-901829) Biomonitoring of chemical pollution in freshwater ecosystems using multiple biomarkers in the zebra mussel, Dreissena polymorpha.

Voets, J¹, Bervoets, L¹, Blust, R¹, ¹ University of Antwerp; Laboratorium for Ecophysiology, Biochemistry and Toxicology, Antwerp, Belgium

ABSTRACT- Chemical monitoring of pollutants in the water and sediment has significant shortcomings in predicting the impact of pollution on aquatic ecosystems. Therefore, measuring micropollutants in biota combined with biomarker responses, is an essential addition to routine chemical monitoring. There is an urgent need for good indicator species and for simple, accurate and cost-effective biomarkers to assess the exposure and the impact of pollutants. In this study, data of several biomonitoring studies are presented whereby zebra mussels (Dreissena polymorpha)are used to evaluate the quality of surface waters in Flanders (Belgium). Zebra mussels are particularly interesting to monitor environmental pollution because they are widespread, efficient accumulators of metals and organic pollutants and given their huge abundance in some surface waters can provide a good indication of pollutants entering the food chain. Accumulated levels of trace metals and organic pollutants (PCBs, HCB, pp'-DDEs and PBDEs) were measured in mussels from locations covering a broad range of environmental pollution. Biomonitoring studies were conducted in locations mostly contaminated with metals, locations polluted with organic compounds, small rivers contaminated with pesticides and in locations with mixed pollution. Concentrations of contaminants in mussels were related to levels in the surrounding environment. Several biomarker responses measured at different level of biological organisation were analysed to assess the impact of the different types of pollutants on the zebra mussels. The biomarkers included in the study were; condition indices (water content, tissue-condition-index), cellular respiration (electron transport activity), energy reserves (protein, lipid and sugar content), mussel survival, osmolality of the haemolymph, acetylcholinesterase activity, metallothionein like proteins and fluctuating asymmetry. Finally, a model will be presented to relate biomarker responses to metal accumulation, whereby metallothionein like proteins are taken into account as a measure for metal detoxification.

Key words: biomonitoring, metals and organic compounds, biomarkers, zebra mussel