Genotoxic and Oxidative Damage of Environmental Pollutant Microplastics on Zebrafish (Danio rerio)

Microplastics are any synthetic solid particles or polymeric matrices ranging in size from 1 to 5 mm and insoluble in water. This study aimed to evaluate the effects of polystyrene (PS) and polyethylene (PE) microplastics on DNA damage (8-OHdG), advanced oxidation protein products (AOPP μM/mg protein), malondialdehyde (MDA nmol/g tissue), and glutathione (GSH μmol/g tissue) in zebrafish. Zebrafish with an average length of 3-5 cm were placed in aquariums filled with spring water with 1-5-μm PE and 9.5-11.5-μm PS at 1- and 10-mg/L concentrations for 96 h and 21 days. The tissue levels of MDA exposed to 1-mg/L PS and PE (p = 0.008, p = 0.041) and GSH exposed to 1- and 10-mg/L PE (p = 0.004, p = 0.004) in 96 h were increased compared to the control group. GSH (1 and 10-mg/L PS in 21 days, p = 0.033, p = 0.045) and AOPP levels (1- and 10-mg/L PS in 96 h, p = 0.008, p < 0001) were decreased compared to the control group. DNA damage at 8-OHdG levels (96 h, 10-mg/L PS, p = 0.030) was decreased compared to the control and increased in the 1-mg/L PE at 21 days (p = 0.028). The 1- and 10-mg/L PE and PS microplastic doses were thought to affect the oxidant-antioxidant system. Besides, they may damage DNA in zebrafish, depending on the dosage and exposure time of the chemicals.