Biochemical markers in feral roach ( Rutilus rutilus) in relation to the bioaccumulation of organic trace pollutants

Abstract

The levels of organic trace contaminants, including polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), were analyzed in sediments and in roach ( Rutilus rutilus, a common fish in Dutch freshwater) from two Amsterdam lakes with different pollutant levels. Roach muscle tissue levels of PCBs and OCPs reflected those found in the sediments. PAH muscle tissue levels, however, were higher in roach from the less polluted lake. In addition, a suite of biochemical parameters was measured in roach livers in order to evaluate their utility as biomarkers of aquatic pollution. None of the phase I-enzymes (total cytochrome P450 [cyt P450], cytochrome b 5 [cyt b 5], cytochrome P450 1A [P450 1A], ethoxyresorufin O-deethylase [EROD] and NADPH cytochrome c reductase [RED]) appeared to be induced in roach from the polluted site. On the contrary, cyt P450 and cyt b 5 were significantly inhibited in roach from the more polluted lake. These findings were consistent with the results of measurements on phase II-enzymes. Glutathione S-transferase [GST] activity was significantly inhibited in roach from the polluted site, while no significant changes in the co-factor levels of glutathione [GSH or GSSG] were observed. Hepatic DNA adduct levels were the same in roach from the more polluted and the less polluted lake. Accordingly, the hepatic biochemical parameters measured in this study cannot be considered reliable indicators of chemical pollution or contaminant stress in roach from the polluted lake.