Study of Some Toxicological Aspects of Titanium Dioxide Nanoparticles Through Oxidative Stress, Genotoxicity, and Histopathology in Tilapia, Oreochromis mossambicus

Extensive use of nanotechnology in multiple commodities is raising concerns about nanotoxicity. In particular, many studies have reported the health-hazardous effects of titanium dioxide nanoparticles (TiO2-NPs). The present study focuses on the toxicity and accumulation of TiO2-NPs in tilapia (Oreochromis mossambicus). For this purpose, tilapia was kept in water tanks, acclimatized for 14 days, and treated with different doses of TiO2 nanoparticles: 0, 0.5, 1.0, and 1.5 mg TiO2-NPs/L. Results revealed an increase in the accumulation of TiO2-NPs with an increase in doses. Moreover, with a higher dose (1.5 mg/L), gills had maximum levels compared to muscles and liver tissues, whereas other doses showed different accumulation patterns. Catalase, glutathione, and lipid peroxidation levels were significantly higher in the gills, and superoxide dismutase levels were significantly higher in the liver. Characteristics like thickening and fusion in lamellae, rupturing of gill filaments, and hyperplasia of gills were also recorded. The phenomenon of increased necrosis and apoptosis in the liver was also noticed with increasing concentration of TiO2-NPs along with the formation of sinusoid spaces and condensed nuclear bodies. Elevated values of olive tail movement and % tail DNA were also noticed with an increased concentration of TiO2-NPs. This study concluded that TiO2-NPs produced oxidative stress by accumulation in soft tissues and induced pathology and genotoxicity.