The effect of microplastics with different colors on some oxidative stress biomarkers in Gambusia holbrooki Girard, 1859

This experiment aims to evaluate the effect of colored microplastics (MPs) on oxidative stress indicators in Gambusia holbrooki. This study hypothesized that the risk of oxidative stress in fish may be different based on MPs’ color. In this study, fish in 7 experimental treatments with two replications, including the control group and six experimental groups, were exposed to 150 micrograms per liter of colored MPs (white, green, yellow, red, blue, and black colors) for 14 days. In the end, some oxidative stress indicators were assayed. Furthermore, the bioaccumulation potential of MPs was measured with an FTIR instrument. The results showed that the activity of superoxide dismutase in the liver of fish exposed to black, yellow, and red MPs is significantly higher than in the control group (P<0.05). In addition, exposure of fish to black, green, and red MPs led to a significant increase in the activity of catalase, glutathione-peroxidase, and glutathione-reductase in liver cells (P<0.05). These results showed that the risk of oxidative stress in fish exposed to black, green, and red MPs was significantly higher than other colored MPs.