Exhaled Breath Reflects Prolonged Exercise and Statin Use during a Field Campaign

Volatile organic compounds (VOCs) in exhaled breath provide insights into various metabolic processes. Among these breath VOCs are, acetone, isoprene, acetaldehyde, ethanol and short chain fatty acids SCFA (acetic acid, propionic acid and butyric acid). The last ones have been of special interest since they are related to gut microbiome health. In this study, we demonstrated an on-line breath sampling protocol and analysis of exhaled breath using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) for use outside the laboratory conditions. Despite no restrictions regarding consumption of food and drinks on the participants, and only 2 minutes sampling time, the methodology proved to be robust and reliable. A cluster of short-chain fatty acids including acetic acid, butanoic acid, and propionic acid were identified in exhaled breath as potential indicators of gut microbiota activity. We have provided novel information regarding the use of breathomics for non-invasive monitoring of changes in human metabolism and especially for the gut microbiome activity