It is well known that air pollution causes negative health effects, especially to the lungs, and that diesel exhaust is one of the major contributors to outdoor air pollution.

Previous studies have shown that exposure to diesel exhaust particles induces airway inflammation, through a mechanism of oxidative stress. However, all living organisms have the ability to protect themselves against oxidative stress through antioxidant defences, such as vitamin C, glutathione and urate present in the airways.

In this study undertaken by Thomas Sandström (Department of Respiratory Medicine and Allergy, University Hospital, Umeå, Sweden) and his European colleagues, healthy human volunteers were exposed to diesel exhaust in a specially designed exposure chamber, at concentrations likely to occur in larger cities during traffic congestion.

During bronchoscopy, a lung investigation, samples were taken from the airways on the day following exposure, to evaluate the inflammatory and antioxidant responses.

It was shown that diesel exhaust induces airway inflammation in the larger airways, but not in the more distal parts of the lungs, where the antioxidant defences were found to be increased.

The authors conclude that diesel exhaust induces inflammation in the lungs and that antioxidants are of importance in the protection of the lungs against the harmful effects of air pollution.

Title of the original article:
Airway antioxidant and inflammatory responses to diesel exhaust exposure in healthy humans

EUROPEAN RESPIRATORY JOURNAL