Increased exhalation of hydrogen peroxide in healthy subjects following cigarette consumption

Sao Paulo Med J. 2000 Jul 6;118(4):93-8. doi: 10.1590/s1516-31802000000400004.


Context: Increased hydrogen peroxide has been described in the expired breath condensate (H2O2-E) of several lung conditions, such as acute respiratory distress syndrome, chronic obstructive pulmonary disease and asthma. This technique has been advocated as being a simple method for documenting airway inflammation.

Objective: To evaluate H2O2-E in healthy cigarette smokers, and to determine the acute effects of the consumption of one cigarette on H2O2-E levels.

Type of study: Prospective, controlled trial.

Setting: A pulmonary function laboratory in a University Hospital.

Participants: Two groups of healthy volunteers: individuals who had never smoked (NS; n=10; 4 men; age = 30.6 +/- 6.2 years) and current cigarette smokers (S; n=12; 7 men; age = 38.7 +/- 9.8). None of the volunteers had respiratory symptoms and all showed normal spirometric tests.

Intervention: Expired air was collected from all volunteers through a face mask and a plastic collecting system leading into a flask with dry ice and pure ethanol. Samples from the group S were collected twice, before and half an hour after the combustion of one cigarette.

Main measurements: Expired hydrogen peroxide using the Gallati and Pracht method.

Results: The S and NS groups showed comparable levels of H2O2-E at basal conditions [NS = 0.74 microM (DP 0.24) vs. S = 0.75 microM (DP 0.31)]. The smokers showed a significant increase in H2O2-E levels half an hour after the consumption of only one cigarette [0.75 microM (DP 0.31) vs. 0. 95 microM (DP 0.22)].

Conclusion: The present results are consistent with the concept that smokers increase oxidative stress with elevated production of reactive oxygen species, contributing to the development of smoking-related disorders.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Adult
  • Breath Tests
  • Female
  • Forced Expiratory Volume
  • Humans
  • Hydrogen Peroxide / analysis
  • Hydrogen Peroxide / metabolism*
  • Lung Diseases, Obstructive / etiology
  • Male
  • Middle Aged
  • Oxidants / analysis
  • Oxidants / metabolism*
  • Oxidative Stress
  • Prospective Studies
  • Smoking / adverse effects*
  • Spirometry


  • Oxidants
  • Hydrogen Peroxide