Categorization of nano-structured titanium dioxide according to physicochemical characteristics and pulmonary toxicity

Publication date: Available online 20 May 2016 Source:Toxicology Reports Author(s): Naoki Hashizume, Yutaka Oshima, Makoto Nakai, Toshio Kobayashi, Takeshi Sasaki, Kenji Kawaguchi, Kazumasa Honda, Masashi Gamo, Kazuhiro Yamamoto, Yasuhiro Tsubokura, Shozo Ajimi, Yoshiyuki Inoue, Nobuya Imatanaka A potentially useful means of predicting the pulmonary risk posed by new forms of nano-structured titanium dioxide (nano-TiO2) is to use the associations between the physicochemical properties and pulmonary toxicity of characterized forms of TiO2. In the present study, we conducted intratracheal administration studies in rats to clarify the associations between the physicochemical characteristics of seven characterized forms of TiO2 and their acute or subacute pulmonary inflammatory toxicity. Examination of the associations between the physicochemical characteristics of the TiO2 and the pulmonary inflammatory responses they induced revealed (1) that differences in the crystallinity or shape of the TiO2 particles were not associated with the acute pulmonary inflammatory response; (2) that particle size was associated with the acute pulmonary inflammatory response; and (3) that TiO2 particles coated with Al(OH)3 induced a greater pulmonary inflammatory response than did non-coated particles. We separated the seven TiO2 into two groups: a group containing the six TiO2 with no surface coating and a group containing the one TiO2 with a surface coating. Intratr...
Source: Toxicology Reports - Category: Toxicology Source Type: research