Induction of hepatic cytochrome P-450 1A in pikey bream (Acanthopagrus berda) collected from agricultural and urban catchments in far north Queensland

A variety of sources of organic contaminants to the Great Barrier Reef lago on and near-shore environment exist including boating activity, agriculture and urban run-off. Cytochrome P-450 1A activity as measured by ethoxyresor ufin O-deethylase (EROD) activity has been widely used as an indicator of t he exposure of fish to organic contaminants such as polychlorinated bipheny ls (PCB), polycyclic aromatic hydrocarbons (PAH) and some organochlorine pe sticides. This study demonstrates the successful application of EROD measur ements in a common Australian tropical estuarine fish species, Acanthopagpu s berda (Pikey Bream), to identify areas under potential stress from organi c contaminants. Fish were captured from four creeks draining agricultural l and, a creek draining urban land and two creeks with less disturbed catchme nts, Significant induction of cytochrome P450-1A was observed in fish captu red from Ross Creek (urban catchment, 7.4-fold) and Cromarty Creek (agricul tural catchment, 6.4-fold). Increased activity was also observed in fish ca ptured from other creeks draining agricultural land (Plantation Creek, Vict oria Creek, Seymour River, 1.9-2.6-fold) as compared to those captured from creeks in undisturbed catchments (Baldy Creek, Fisher Creek, 67-114 pmol/m in/mg protein). (C) 2000 Elsevier Science Ltd, All rights reserved.