Toxicity of nano-anatase TiO₂to mice: Liver injury, oxidative stress

The mechanism of oxidative damage in the nephrotoxicity of mice caused by nano-anatase TiO2

“…Afaq et al [20] reported that nano-TiO 2 could increase the activities of enzymatic antioxidants in alveolar macrophage, but elevate the level of lipid peroxidation and increase the accumulation of ROS. However, Liu et al [18] proved that the activities of antioxidative enzymes from mice liver were significantly reduced, and O À 2 , H 2 O and lipid peroxidation levels were elevated by higher nano-anatase TiO 2 dose. In the experiments, we also observed that the activities of SOD, CAT and APx of the kidney of mice injected by various nano-anatase TiO 2 doses were significantly inhibited (Table 5).…”

“…Such widespread use and its potential entry through dermal, ingestion and inhalation routes suggest that nanotitanium dioxide (nano-TiO 2 ) could pose an exposure risk to humans, though TiO 2 was considered to be biologically inert [4][5][6][7]. Recent investigations have unequivocally showed that exposure to nano-TiO 2 caused inflammation of the liver, kidney, spleen, lung, heart and brain as well as tumours [2,[8][9][10][11][12][13][14][15][16][17][18]. Human polymorphonuclear leukocytes exposed to TiO 2 (containing 90% anatase/10% rutile, 345 and 431 nm) dust produced enhanced levels of reactive oxygen species (ROS) quantified by chemiluminescence assay [1].…”

Toxicological Issues of Nanoparticles Employed in Photocatalysis

“…Lee and coworkers exposed rats to TiO 2 by inhalation exposure with concentrations of 0, 10, 50, and 250 mg=m 3 for 6 h=day, 5 days=week for 2 years and found no abnormal clinical signs, no body weight changes, and no excess mortality in any exposed group. However, the exposed groups showed slight increases in the incidence of pneumonia, tracheitis, and rhinitis, and obvious hepatic damage and renal lesion in female mice [188]. TiO 2 particles were found to be mainly retained in liver, kidney, spleen and lung [189].…”

“…The effect of various TiO 2 particles in mice, rats, and hamsters after oral exposure and instillation [180], [181], [182], [183], [184], [185], [186], injection [187], [188] and inhalation [189], [181], [190], [191] has been studied in detail.…”

Nanoparticles Toxicity and Their Routes of Exposures

“…The mechanism by which TiO2 NPs can generate free radicals is through decreasing the activities of antioxidant enzymes such as SOD, CAT, GPx and glutathione reductase (GR) or intracellular levels of antioxidants such as GSH and ascorbic acid [24][25][26][27].…”