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(80-20) European eel exposed to Aroclor 1254: correlation between PCB muscle content and EROD activity. Mariottini, Michela*,1, Corsi, Ilaria1, Bonacci, Stefano1, Focardi, Silvano1, Regoli, Francesco2, 1 University of Siena, Siena, Italy2 University of Ancona, Ancona, Italy ABSTRACT- The European eel (Anguilla Anguilla L.) is an euryaline fish that lives in the brackish water areas feeding on natural food available in bottom sediments. It is particularly suitable for the study of persistent and lipophilic pollutants such as polychlorinated biphenyls (PCBs) due to the high lipid contents. Cytochrome P-4501A1, measured by 7-ethoxyresurfin-O-deethylase activity (EROD), can be specifically induced by PCBs and provides a quantitative measurement even if the relative inductions by various PCB congeners have yet to be defined. Twenty European eels were captured from a brackish lagoon along the Tyrrhenian coast of Italy, acclimatised in the laboratory and then exposed to Aroclor 1254 by single intraperitoneal injections using corn oil as carrier at 0.1, 1, 10, 50 mg/Kg body weight. Fish muscle was analysed for PCBs by GC-ECD and GC-MS. EROD activity was performed in the liver microsomial fraction. Significant differences among PCB levels in fish exposed to the various doses were observed while fingerprints showed different patterns of PCBs respect to controls. Highly positive correlation (r=0.80; p<0.001) was found between PCB content and EROD activity, which was also confirmed by high correlation with P450 inducing congeners in the Aroclor 1254 mixture (r=0.81; p<0.001). Possible correlations between EROD and calculated TEQ values were investigated. EROD activity increased at increasing doses from controls to a maximum dose of 50 mg/Kg. These results show a clear P450 response in the European eel exposed to Aroclor 1254 indicating the suitability of this species as bioindicator for monitoring both the presence and the effects of lipophilic pollutants in Mediterranean brackish environments. Key words: Aroclor 1254, European eel, biomarkers, bioindicator |
