Respiratory and blood responses following intratracheal instillation of titanium dioxide nanoparticles in rabbits

Nowadays، nanomaterials are used in daily life extensively. One of the most common of these materials is nano titanium dioxide (TiO2) which is used to purify the air and also sunscreens، shampoos and other hygienic products. Although nano-particles are useful، can also have potential hazards. The aim of this study is to evaluate the effects of TiO2 on lung tissue in rabbits. We divided 18 male rabbits into three groups randomly. The first group recei-ved 50 µl of TiO2 with dose of 50 mg/kg by intratracheal instillation. The second group received 50 µl of TiO2 with dose of 100 mg/kg and the third group received 50 µl of nor-mal saline by the same route. Chest X-rays were taken from all rabbits before injection and on days of 10، 17 and 24 after injection. Twenty four days after injection، rabbits anesthetized and histopathological assays، blood samples and biochemical factors were evaluated. Radiographic assays showed a progressive pulmonary fibrosis in rabbits recei-ved TiO2 rather than the control group and this lesion developed to maximum at 24th day of the experiment. We also showed pulmonary emphysema and inflammation in histo-pathologycal study of groups treated with TiO2. Moreover، we observed a significant increase in the amount of liver enzymes، white blood cells and hematocrit in TiO2 treat-ed groups compared to control group (P≤0. 05). There were no significant differences between plasma levels of creatinine in different groups (P>0. 05). Results showed that nanotitanium dioxide particles can lead to pulmonary fibrosis and inflammation and also increasing liver enzymes and inflammatory cells.