The benzo[a]pyrene is a polycyclic aromatic hydrocarbon known to be genotoxic, mutagenic and carcinogenic in higher vertebrates. The aim of this study was to evaluate in vitro the enzymatic and genotoxic effects of BaP in a benthic fish species, Solea solea. Sole hepatocytes were exposed to BaP in order to measure the modulation of ethoxyresorufin-o-deethylase (EROD) activity and the DNA strand breaks induced by BaP metabolism. Exposures were performed in both culture flasks and microplate wells in order to check for the possible miniaturization of the exposure system. Moreover, sole liver microsomes were exposed to BaP in the presence of standard DNA in order to assess the potential formation of DNA adducts in sole. The results demonstrated the ability of sole hepatic enzymes to metabolize BaP into reactive species responsible for bulky DNA adducts and DNA strand breakage, whatever the tested exposure concentration and the mode of exposure.