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(T/EH043) The energy metabolism of Neomysis integer : a new biomarker for endocrine disruption in estuaries ? Verslycke, Tim1, Janssen, Colin1, 1 ABSTRACT- Few environments expose their inhabitants to such a variety of abiotic variables (e.g. temperature, salinity, dissolved oxygen) and of such large magnitude, as does an estuary. Moreover, estuaries worldwide are contaminated with a wide range of environmental pollutants, many of these are potential endocrine disrupters. It is therefore hypothesised that through the interaction of abiotic and toxic stresses, certain estuarine animals could be environmental sentinels for the effects of environmental endocrine disrupters. The energy metabolism is under hormone control and therefore susceptive to endocrine disruption. Changes in the energy metabolism, in general, will ultimately influence future life characteristics such as growth and reproduction. In this context, a new methodology (Cellular Energy Allocation, CEA) to assess the energy budget was adopted for the estuarine crustacean Neomysis integer (De Coen and Janssen, J. Aq. Ecos. Stress Recov., 6, 43-55, 1997). Available energy reserves (total carbohydrate, lipid and protein content) and energy consumption (electron transport activity) were quantified biochemically and integrated into a general stress indicator. To assess the natural variability of this biomarker, a fractional factorial test design was set up with different natural occurring combinations of temperature, salinity and dissolved oxygen. The importance of natural variability versus toxic response of the energy metabolism of N. integer is described. These results provide new insights into the use of biomarkers in general, but also add to the discussion of biomarker variability under field conditions. By modelling the influence of these abiotic stresses on the energy metabolism (CEA) of N. integer, it will be possible to use the CEA as an ecologically relevant biomarker for endocrine disruption in estuaries. Key words: energy metabolism, Neomysis integer , endocrine disruption, abiotic stress |
