Exhaled breath condensate
Exhaled breath condensate (EBC) is the exhalate from breath, that has been condensed, typically via cooling using a collection device (commonly to 4 °C or subzero temperatures using a refrigerating device). EBC reflects changes in the respiratory fluid that lines the airways and is an inexpensive, non-invasive tool that has potential for scientific research. Despite its promises, it has not been proven for screening or diagnosing diseases of the lung and other conditions, yet. It has long been appreciated that the exhaled breath is saturated by water vapour (e.g. by wind musical instrument players), but using it for studies of the lung was probably first described in the Russian scientific literature. Overview Exhaled breath condensate reflects not only the composition of the airway lining fluid and alveoli. EBC may also mix with salivary and gastric droplets. In addition, volatile gases arising from the alveoli, lower and upper airway wall as well as oral cavity dissolve into the exhaled water vapour and influence its pH. The primary constituents of EBC include: Aerosolised particles of airway lining fluid collected from the airways induced by airflow, probably by turbulence. Water vapour condensation produced around the aerosolised particles Water-soluble volatile gases dissolved into the