The evaluation of water quality in Karakaya Dam Lake: An ecotoxicological approach

Ecotoxicological results of man made environmental pollution in Karakaya Dam Lake were evaluated in this biomonitoring study. The carp (Cyprinus carpio) captured from different localities in the lake between 2004 and 2006 were used to determine selected biomarkers. Also, water samples from the same region were collected to determine some of its physico-chemical parameters. Liver 7-ethoxyresorufin Odeethylase (EROD), glutathione S-transferase (GST), glutathione reductase (GR), carboxylesterase (CaE) activities; liver and plasma aspartate and alanine aminotransferase (AST and ALT), lactate dehydrogenase (LDH) activities; plasma vitellogenin (VTG) concentration were determined. Furthermore, hepatosomatic index and condition factor were calculated. A similar study was also conducted for one season period in Sultansuyu Dam Lake to compare the results of these two nearby lakes. Some fish samples were exposed to 17ß-estradiol in laboratory conditions for induction of VTG and results were compared to fish samples of Karakaya Dam Lake. Comparison of the selected biomarker results and physico-chemical analysis of water showed that the selected markers were most suitable for this biomonitoring study. Especially EROD, AChE, HIS, CF and VTG results showed good correlation and more sensitivity with sampling seasons and stational differences. ALT, AST, LDH, GST and GR activities were also represented further evidence about water pollution. Depending on the physico-chemical analysis results of water, we assumed that lead being the most contributing pollutant, Karakaya Dam Lake is polluted by a number of pollutants. In this regard, nitrite, total organic carbon level, copper and phosphate values were also determined as seasonal pollutants in some stations. Both biomarker values and physicochemical parameters of water showed that the dam lake