Toxicity assessment of simulated urban runoff containing polycyclic musks and cadmium in Carassius auratus using oxidative stress biomarkers.

The objective of this study was to assess potential toxic effects of simulated urban runoff on Carassius auratus using oxidative stress biomarkers. The activity of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and the content of malondialdehyde (MDA) in the liver of C. auratus were analyzed after a 7-, 14- and 21-day exposure to simulated urban runoff containing galaxolide (HHCB) and cadmium (Cd). The results showed that the activity of antioxidant enzymes and the content of MDA increased significantly exposed to the simulated urban runoff containing HHCB alone or mixture of HHCB and Cd. The activity of the investigated enzymes and the content of MDA then returned to the blank level over a longer period of exposure. The oxidative stress could be obviously caused in the liver of C. auratus under the experimental conditions. This could provide useful information for toxic risk assessment of urban runoff.