Effects of food limitation on 9 metal concentrations in liver and polycyclic aromatic hydrocarbon metabolites in bile of juvenile turbot (Scophthalmus maximus) previously exposed to contaminated sediments.
A 2-step experimental design was employed in the present study on juvenile turbot (Scophthalmus maximus): 1) juveniles were exposed for 26 d to 2 contaminated sediments and a reference one, and 2) they were transferred in clean seawater with clean sediment for 35 d, feeding fish once a day, twice a week, or once a week. Fish exposed to contaminated sediments presented a significant increase of hepatic Cd, Cu, and Pb concentrations compared with the reference condition after the 26-d exposure. Higher fluorescence signals of polycyclic aromatic hydrocarbon (PAH) metabolites were found in bile from turbot exposed to contaminated sediments for 26 d compared with reference. These signals returned to values similar to reference fish after depuration whatever the food quantity. The metal bioaccumulation of Cd, Cu, and Pb was no longer observed after 35-d depuration with once-a-day feeding but was still found with restricted feeding conditions. Results on reference fish also showed significantly higher concentrations of most metals analyzed in fish fed twice a week and once a week compared with fish fed once a day. These results could be related to a decrease of fish hepatosomatic index with food limitation and, thus, a dilution effect on metal concentrations. The present study clearly demonstrates that changes in feeding status have significant effects on metal concentrations in fish and no observed effect on PAH metabolites.