[EBC: a new matrix for assessment of airway and lung inflammation. Current aspects of environmental and occupational medicine]

Abstract

For many environmental and occupational pollutants the respiratory system represents the route of entry. Inflammation is a fundamental process in the pathophysiological cascade leading to respiratory diseases such as asthma or chronic obstructive pulmonary disease. Non-invasive inflammatory monitoring may assist in the diagnosis as well as assessments of severity and response to treatment. Of these, exhaled nitric oxide is the best validated constituent and is used for assessing airway inflammation in clinical practice, particularly in patients with asthma. Exhaled breath condensate (EBC) is the liquid phase of the exhaled breath sampled by cooling. EBC, like blood or urine, is not a marker itself but a matrix in which a wide variety of substances have already been detected. EBC biomarkers reflect acid stress, oxidative stress, or inflammation. There are still many methodological limitations and the interpretation of findings is hampered by the fact that the most widely used devices differ significantly in their collection efficiency for markers of interest and the analytical technology employed is often near the limit of detection. In spite of promising data, standardisation of the already existing procedures is required for the implementation of EBC in clinical practice. EBC might be of particular interest in preventive medicine since adverse inflammatory processes often precede changes in lung function. Concerning the adverse effects of air pollution, there is a special focus on markers reflecting oxidative stress since air pollutants have the ability to drive free radical reactions. This overview focuses on recent data on EBC obtained from articles concerning applications of exhaled breath analysis in environmental and occupational medical research.