Copper accumulation and toxicity in the plata pompano trachinotus marginatus cuvier 1832 (teleostei, carangidae)

The Plata pompano Trachinotus marginatus inhabits the surf zone of sandy beaches in Southern Brazil. Increasing copper concentrations have been reported in this ecosystem likely associated with the growing industrial and urban activities in the surrounding area. In the present study, copper accumulation and toxicity were analyzed in T. marginatus acclimated to salinity 30. Toxicity tests were performed to determine the copper concentration lethal for 50% of the individuals tested after 96 h (LC50). Based on dissolved copper concentrations, LC50 was estimated at 0.449 mg/L. To determine gill copper accumulation, fish were exposed (96 h) to 0.146 (sublethal concentration) and 0.369 mg/L dissolved copper (lethal concentration). Gill copper accumulation linearly increased as a function of the exposure time when fish were exposed to the sublethal concentration. However, a saturation of copper binding sites was observed after 6 h of exposure to the lethal concentration. The maximum copper accumulation in gills was estimated at 11.85 μg/g dry weight. These findings indicate that T. marginatus tolerance to copper is similar to that shown by other pompano species. They also suggest that gills are a biotic ligand for copper in T. marginatus that could be used to model the toxic effects of this metal.