title: Pulmonary toxicity of well-dispersed titanium dioxide nanoparticles following intratracheal instillation.
abstract: In order to investigate the pulmonary toxicity of titanium dioxide (TiO2) nanoparticles, we performed an intratracheal instillation study with rats of well-dispersed TiO2nanoparticles and examined the pulmonary inflammation and histopathological changes in the lung. Wistar Hannover rats were intratracheally administered 0.2 mg (0.66 mg/kg) and 1.0 mg (3.3 mg/kg) of well-dispersed TiO2nanoparticles (P90; diameter of agglomerates: 25 nm), then the pulmonary inflammation responses were examined from 3 days to 6 months after the instillation, and the pathological features were examined up to 24 months. Transient inflammation and the upregulation of chemokines in the broncho-alveolar lavage fluid were observed for 1 month. No respiratory tumors or severe fibrosis were observed during the recovery time. These data suggest that transient inflammation induced by TiO2may not lead to chronic, irreversible legions in the lung, and that TiO2nanoparticles may not have a high potential for lung disorder.
authors.affiliation: Department of Occupational Pneumology, Institute of Industrial Ecological Science, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Yoshiura
authors.affiliation: Department of Occupational Pneumology, Institute of Industrial Ecological Science, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Izumi
authors.affiliation: Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Oyabu
authors.affiliation: Department of Occupational Pneumology, Institute of Industrial Ecological Science, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Hashiba
authors.affiliation: Department of Occupational Pneumology, Institute of Industrial Ecological Science, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Kambara
authors.affiliation: Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Mizuguchi
authors.affiliation: Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Byeong Woo
authors.initials: BW
authors.lastname: Lee
authors.affiliation: Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Takami
authors.initials: T
authors.lastname: Okada
authors.affiliation: Department of Occupational Pneumology, Institute of Industrial Ecological Science, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Taisuke
authors.initials: T
authors.lastname: Tomonaga
authors.affiliation: Department of Environmental Health Engineering, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Myojo
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: National Sanatorium Hoshizuka Keiaien, 4204 Hoshizuka-cho, Kanoya, Kagoshima 893-8502 Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kitajima
authors.affiliation: Health Research Institute (HRI), National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa 761-0395 Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Horie
authors.affiliation: Laboratory of Vaccine Science, WPI Immunology Frontier Research Center, Osaka University, 6F IFReC Research Building, 3-1 Yamada-oka, Suita, Osaka 565-0871 Japan.
authors.forename: Etsushi
authors.initials: E
authors.lastname: Kuroda
authors.affiliation: Department of Occupational Pneumology, Institute of Industrial Ecological Science, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Morimoto
keywords: Chemokine; Environmental and health effects; Intratracheal instillation; Nanoparticle; Pulmonary inflammation; Titanium dioxide