Comparative antioxidant responses in liver of Carassius auratus exposed to phthalates: An integrated biomarker approach

•Antioxidant responses in fish exposed to 17 different PAEs were evaluated.•Activities of antioxidant enzymes (SOD, CAT, and GPx) were significantly decreased after short-term exposure.•Toxicity order was proposed via the IBR index, with DCHP the most toxic and DEP the least.

Phthalates (PAEs) are chemical agents typically used as plasticizers in numerous industrial products. They have become ubiquitous contaminants due to their tendency to release into the environment. The present study was conducted to investigate the comparative antioxidant responses in liver of freshwater goldfish Carassius auratus injected intraperitoneally with 17 different PAEs at a concentration of 10 mg/kg for 10 days. The results indicated that these PAEs can adversely affect the antioxidant status, confirmed by the significantly inhibited activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase). Especially, the latter two enzymes constituted the most affected antioxidant enzymes after the exposure, and the lowest values were recorded for the catalase activity. The toxicity order was proposed via the integrated biomarker response, with dicyclohexyl phthalate the most toxic and diethyl phthalate the least. Overall, these findings may contribute to the risk assessments of these chemicals on aquatic species.