Breath analysis

Breath is a mixture of predominantly nitrogen, oxygen and carbon dioxide, plus some water vapour and inert gases, and trace amounts - parts per million (by volume) to parts per trillion - of volatile organic compounds (VOCs). Despite their low concentrations, these trace species reflect many processes occurring in the body. Endogenous (produced in the body) VOCs are the products of normal metabolism and of metabolic pathways that have altered owing to disease, and are transported via the bloodstream to the lungs where they are exhaled in breath.¹  Analysis of breath could potentially provide a non-invasive means to assess a person's state of health.