Organochlorine bioaccumulation and biomarkers levels in culture and wild white seabream (Diplodus sargus)

Persistent organic pollutants (POPs), which can accumulate in the adipose fish tissues, can enter the human food chain through the consumption of fish, and cause risk to health. The use of chemical analysis, and biochemical and cellular responses is a way to detect the impact of pollutants in aquatic systems. The purpose of this study was to investigate the levels of organochlorine compounds (polychlorinated biphenyls - PCB and p,p'-dichlorodiphenyltrichloroethane and its metabolites - tDDT) in, wild and cultivated, white seabream (Diplodus sargus), and also its biological effects that were evaluated by assessing the activity of biotransformation enzymes and genotoxic effects. To achieve that we have sampled five different size classes (I - 13 g, II - 64 g, III - 143 g, IV - 315 g and V - 441 g) of white seabream from a local aquaculture, and also a group of wild fish (375g) in order to compare accumulation and responses between cultured and wild fish. White seabream, cultured and wild, presented low levels of organochlorine content, both in liver and in muscle. Wild white seabream, in comparison to cultured ones at the marketable size, showed lower organochlorine accumulation. Biotransformation enzymes showed negative correlations with organochlorine levels in liver. Micronucleous numbers revealed that wild white seabream are not so exposed to genotoxic compounds as cultured ones.