Toxicological evaluation of lung responses after intratracheal exposure to non-dispersed titanium dioxide nanorods

Details

• Personal Author:
  Antonini JM ; Chapman RS ; Chen BT ; Karim A ; Leonard, Stephen S. ; Roberts, Jennifer R. ; Schwegler-Berry D ; Stefaniak, Aleksandr B. ; Tirumala VR
• Description:
  Fine- and coarse-sized titanium dioxide (TiO2) particles are considered to be relatively inert when inhaled. The goal of this study was to assess potential lung toxicity associated with well-characterized, non-dispersed rutile TiO2 nanorods (10 x 40 nm). In vitro bioreactivity of TiO2 nanorods was determined by electron spin resonance (ESR) to measure free radical production. To assess pulmonary effects in vivo, Sprague-Dawley rats were intratracheally instilled with saline, silica, or TiO2 nanorods (10 ug, 100 ug, or 1 mg/rat). On d 1, 3, and 6 posttreatment, left lungs were preserved for microscopy and histopathology, and lung lavage was performed on right lungs. Additional rats were treated with saline or TiO2 nanorods (100 ug or 1 mg/rat) on d 0, intratracheally inoculated with 5 x 10(5) Listeria monocytogenes on d 3, and bacterial clearance was assessed. ESR showed a significant concentration-dependent generation of hydroxyl radicals by TiO2 nanorods in the presence and absence of macrophages; however, the hydroxyl radical signals from TiO2 samples were low compared to silica. Rats exposed to 1 mg of TiO2 nanorods had significantly elevated levels of lung injury, inflammation, and lavage fluid monocyte chemoattractant protein (MCP)-1 and macrophage inflammatory protein (MIP)-2 on d 1 and 3 that subsided by d 6, unlike the silica response that persisted. Immune cytokine secretion in the lung and bacterial clearance were not affected by preexposure to TiO(2) nanorods. To summarize, non-dispersed TiO(2) nanorods were found to induce radical formation and cellular oxidant production, and to generate transient and reversible pneumotoxic effects, and to not markedly alter pulmonary immune function. [Description provided by NIOSH]
• Subjects:
  Animals Hazardous Substances Immune System Irritants Laboratories Lung Lung Diseases Microbiology Occupational Health Particulate Matter Respiratory Hypersensitivity Respiratory System Respiratory Tract Diseases Safety Toxicology

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• Keywords:
  Alveolar-cells Animal-studies Biological-effects Biological-systems Immune-reaction Laboratory-animals Laboratory-testing Lung-disorders Lung-irritants Microscopic-analysis Nanotechnology Particle-aerodynamics Particulates Physiological-effects Physiological-response Pulmonary-system Pulmonary-system-disorders Quantitative-analysis Respiratory-hypersensitivity Respiratory-irritants Respiratory-system-disorders Tissue-disorders Toxic-effects

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• ISSN:
  1528-7394
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  Maryland ; OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division ; DRDS - Division of Respiratory Disease Studies
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  74
• Issue:
  12
• NIOSHTIC Number:
  nn:20038716
• Citation:
  J Toxicol Environ Health A 2011 May; 74(12):790-810
• Contact Point Address:
  Jenny R. Roberts, PhD, Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), 1095 Willowdale Rd. (M/S 2015), Morgantown, WV 26505, USA
• Email:
  jur6@cdc.gov
• CAS Registry Number:
  Silica (CAS RN 7631-86-9) ; Titania (CAS RN 13463-67-7)
• Federal Fiscal Year:
  2011
• NORA Priority Area:
  Manufacturing
• Peer Reviewed:
  True
• Source Full Name:
  Journal of Toxicology and Environmental Health, Part A: Current Issues
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:82627930753211fa754565fd33046f792d3a918d91036ff7424746f235cb75e009cb367f58cfb7df2192b8eb150fa165eb9d5ff6da963e5113e90de041f6f527
• Download URL:
  https://stacks.cdc.gov/view/cdc/192331/cdc_192331_DS1.pdf
• File Type:
  [PDF - 1006.22 KB ]