Affiliation: | aCooperative Research Centre for Sustainable Sugar Production, James Cook University of North Queensland, PO, Townsville 4811, Qld, Australia bCRC Reef Research Centre, James Cook University of North Queensland, PO, Townsville 4811, Qld, Australia cAustralian Institute of Marine Science, PMB 3, Townsville MC 4810, Qld, Australia dJames Cook University of North Queensland, PO, Townsville 4811, Qld, Australia eAgriculture and Agri-Food Canada, 32 Main Street, Kentville, Nova Scotia, Canada B4N IJ5 fKey Centre for Applied and Nutritional Toxicology, RMIT-University, Melbourne 3000, Vic., Australia |
Abstract: | A variety of sources of organic contaminants to the Great Barrier Reef lagoon and near-shore environment exist including boating activity, agriculture and urban run-off. Cytochrome P-450 1A activity as measured by ethoxy-resorufin O-deethylase (EROD) activity has been widely used as an indicator of the exposure of fish to organic contaminants such as polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAH) and some organochlorine pesticides. This study demonstrates the successful application of EROD measurements in a common Australian tropical estuarine fish species, Acanthopagrus berda (Pikey Bream), to identify areas under potential stress from organic contaminants. Fish were captured from four creeks draining agricultural land, a creek draining urban land and two creeks with less disturbed catchments. Significant induction of cytochrome P450-1A was observed in fish captured from Ross Creek (urban catchment, 7.4-fold) and Cromarty Creek (agricultural catchment, 6.4-fold). Increased activity was also observed in fish captured from other creeks draining agricultural land (Plantation Creek, Victoria 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/min/mg protein). |