title: Pulmonary toxicity of indium-tin oxide production facility particles in rats.
abstract: Indium-tin oxide (ITO) is used to make transparent conductive coatings for touch-screen and liquid crystal display electronics. Occupational exposures to potentially toxic particles generated during ITO production have increased in recent years as the demand for consumer electronics continues to rise. Previous studies have demonstrated cytotoxicity in vitro and animal models have shown pulmonary inflammation and injury in response to various indium-containing particles. In humans, pulmonary alveolar proteinosis (PAP) and fibrotic interstitial lung disease have been observed in ITO facility workers. However, which indium materials or specific processes in the workplace may be the most toxic to workers is unknown. Here we examined the pulmonary toxicity of three different particle samples that represent real-life worker exposures, as they were collected at various production stages throughout an ITO facility. Indium oxide (In2O3), sintered ITO (SITO) and ventilation dust (VD) particles each caused pulmonary inflammation and damage in rats over a time course (1, 7 and 90 days post-intratracheal instillation), but SITO and VD appeared to induce greater toxicity in rat lungs than In2O3 at a dose of 1 mg per rat. Downstream pathological changes such as PAP and fibrosis were observed in response to all three particles 90 days after treatment, with a trend towards greatest severity in animals exposed to VD when comparing animals that received the same dose. These findings may inform workplace exposure reduction efforts and provide a better understanding of the pathogenesis of an emerging occupational health issue.
authors.affiliation: Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Badding
authors.affiliation: Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
authors.forename: Natalie R
authors.initials: NR
authors.lastname: Fix
authors.affiliation: Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
authors.forename: Marlene S
authors.initials: MS
authors.lastname: Orandle
authors.affiliation: Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Barger
authors.affiliation: Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Dunnick
authors.affiliation: Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
authors.forename: Kristin J
authors.initials: KJ
authors.lastname: Cummings
authors.affiliation: Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Leonard
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D018893:Bronchoalveolar Lavage; D004305:Dose-Response Relationship, Drug; D004391:Dust; D006863:Hydrogen-Ion Concentration; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008168:Lung / Q000187:drug effects / Q000473:pathology; D008297:Male; D010587:Phagocytosis; D011014:Pneumonia / Q000139:chemically induced / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017971:Tin Compounds / Q000633:toxicity*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000393:Air Pollutants; D004391:Dust; D053583:Interleukin-1beta; D015850:Interleukin-6; D017971:Tin Compounds; D014409:Tumor Necrosis Factor-alpha; C109984:indium tin oxide
keywords: cytokines; indium-tin oxide; occupational exposure; phagocytosis; pulmonary toxicity