Are internal concentrations of micro pollutants in aquatic organisms predictive of the ecological quality of water courses?

For the monitoring of pollutants in the aquatic environment and the prediction of their ecological effects on aquatic organisms, most of the time only water, sediment or suspended matter is measured. However, with this approach the results only reflect the situation at the moment of sampling while concentrations might fluctuate with time. Moreover, this approach does not take into account the bio-availability, which is influenced by factors such as acidity, water hardness and temperature and that may differ substantially among sites. Therefore it makes more sense to measure toxic compounds in organisms that are resistant to pollution and that easily accumulate them. In this way fluctuations in time and differences in accumulation are integrated in the measurement. The aim of this study is to look for species (invertebrates and fish) that can be collected from natural waters (rivers, lakes, canals) or introduced in cages and in which accumulation of micro pollutants is assessed. The accumulated levels of pollutants and internal distribution will be related to the invertebrate and fish community structure. In order to confirm field results, also laboratory and mesocosm (artificial ponds) experiments will be performed in which invertebrates are exposed to the pollutants and effects on physiology, reproduction and behavior will be assessed. In this way we will investigate if this approach is suitable to derive biota quality standards that are protective of ecological damage. -

Keywords:ECOLOGICAL QUALITY OBJECTIVES

Disciplines:Aquatic biology, Environmental monitoring