Nitrogen dioxide exposure: Effects on airway and blood cells

Mark W. Frampton, Joseph Boscia, Norbert J. Roberts, Mitra Azadniv, Alfonso Torres, C. O.X. Christopher, Paul E. Morrow, Joan Nichols, David Chalupa, Lauren M. Frasier, F. Raymond Gibb, Donna M. Speers, Ying Tsai, Mark J. Utell

Research output: Contribution to journalArticlepeer-review

65 Scopus citations


This study examined the effects of nitrogen dioxide (NO2) exposure on airway inflammation, blood cells, and antiviral respiratory defense. Twenty-one healthy volunteers were exposed on separate occasions to air and 0.6 and 1.5 ppm NO2 for 3 h with intermittent moderate exercise. Phlebotomy and bronchoscopy were performed 3.5 h after each exposure, and recovered cells were challenged with respiratory viruses in vitro. Blood studies revealed a 4.1% NO2 dose-related decrease in hematocrit (P = 0.003). Circulating total lymphocytes (P = 0.024) and T lymphocytes (P = 0.049) decreased with NO2 exposure. Exposure to NO2 increased the blood lymphocyte CD4+-to-CD8+ ratio from 1.74 ± 0.11 to 1.85 ± 0.12 in males but decreased it from 1.88 ± 0.19 to 1.78 ± 0.19 in females (P < 0.001 for gender difference). Polymorphonuclear leukocytes in bronchial lavage increased with NO2 exposure (P = 0.003). Bronchial epithelial cells obtained after exposure to 1.5 ppm NO2 released 40% more lactate dehydrogenase after challenge with respiratory syncytial virus than with air exposure (P = 0.024). In healthy subjects, exposures to NO2 at levels found indoors cause mild airway inflammation, effects on blood cells, and increased susceptibility of airway epithelial cells to injury from respiratory viruses.

Original languageEnglish (US)
Pages (from-to)L155-L165
JournalAmerican Journal of Physiology - Lung Cellular and Molecular Physiology
Issue number1 26-1
StatePublished - 2002


  • Air pollution
  • Blood
  • Epithelial cells
  • Influenza virus
  • Respiratory syncytial virus

ASJC Scopus subject areas

  • Physiology
  • Pulmonary and Respiratory Medicine
  • Physiology (medical)
  • Cell Biology


Dive into the research topics of 'Nitrogen dioxide exposure: Effects on airway and blood cells'. Together they form a unique fingerprint.

Cite this