Snippets from the Research world – Exhaling the evidence: markers of oxygen toxicity in divers’ breath

When lungs are exposed for long periods to high levels of oxygen it can cause discomfort and acute respiratory distress.  First discovered in 1899 by Lorrain Smith, pulmonary oxygen toxicity (POT) has been widely studied in divers.

In recent years it has been possible to detect novel volatile organic compounds (VOCs) in the breath of subjects breathing high partial pressures of oxygen for a prolonged time, providing a new means of studying the pre-clinical progression of pulmonary oxygen toxicity.

To date studies had only been undertaken in hyperbaric chambers and shallow diving environments, but in a recent paper published in Diving and Hyperbaric Medicine,  Feiko de Jong and co-workers from the Netherland took research a stage further and studied VOCs in the breath of heliox divers after dives to 81m seawater.

The study showed that even in deep heliox dives with surface recompression on oxygen, the production of the VOCs is reversible and the results supported previous findings that pulmonary oxygen toxicity develops sub-clinically before there are any discernible symptoms.  More research is certainly required but the ability to capture specific VOCs in exhaled breath in operational setting provides a tool to further explore the dose-response relationship.  It also opens the door to studying factors such as the potential protective effects of breathing helium  compared to nitrogen in both controlled and real-world situations.

de Jong FJM, Brinkman P, Wingelaar TT, van Ooij PJAM, van Hulst RA. Pulmonary oxygen toxicity breath markers after heliox diving to 81 metres. Diving and Hyperbaric Medicine. 2023 December 20;53(4):340−344. doi: 10.28920/dhm53.4.340-344. PMID: 38091594.