Integrated assessment of biomarker responses in common carp (Cyprinus carpio) exposed to perfluorinated organic compounds

In this study, the toxicological effects of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) toward the common carp, Cyprinus carpio, were evaluated by assessing the responses of five biomarkers, including DNA single-strand breaks (COMET), vitellogenin (VTG) concentration, and the activities of 7-ethoxyresorufin-O-deethylase (EROD), acetylcholinesterase (AChE) and catalase (CAT). Upon PFOA exposure, both the VTG concentration and CAT activity were significantly increased, while there was a negligible change in the responses of other biomarkers when compared to the control. Upon PFOS exposure, a significant increase in the DNA single-strand breaks was observed, while the responses of other biomarkers were not significantly altered when compared to the control. Standardized scores of biomarker responses were visualized using star plots and computed as the integrated biomarker response (IBR). As expected from the different biomarker responses, PFOA and PFOS showed totally different patterns of star plots. Additionally, the IBR values were well correlated with the logarithmic concentrations of PFOA and PFOS (R2 = 0.9434 and 0.9511, respectively). These results suggest that the IBR might be a useful tool for quantification of various biomarker responses induced by toxic chemicals.