Dental sedation using nitrous oxide identified as significant contributor to greenhouse gas emissions in the United Kingdom

UCL study reveals the environmental impact of dental 'laughing gas,' equating one appointment's emissions to a 72-mile car journey.

By: AXL Media

Published: Mar 2, 2026, 8:45 AM EST

Source: The information in this article was sourced from Air Quality News

Environmental Cost of Clinical Sedation

A study led by University College London (UCL) has highlighted the hidden environmental toll of nitrous oxide, a common sedative used to manage patient anxiety. While the gas has a long-standing safety record for procedures such as root canals and fillings, it possesses a global warming potential 273 times greater than carbon dioxide. Researchers found that the average carbon footprint per sedation episode is 28.6 kilograms of carbon dioxide equivalent, illustrating a substantial conflict between clinical necessity and environmental sustainability.

Variations in Delivery and Wastage

The research analyzed 891 sedation episodes across 31 dental services and discovered massive disparities in how the gas is managed. Services using centrally piped delivery systems exhibited 30% higher wastage on average compared to those utilizing individual gas cylinders. Weekly emissions at the service level ranged from 38.9 kg to a staggering 1,849 kg of carbon dioxide equivalent. Lead author Alexandra Lyne noted that these differences are largely due to inconsistent supply and administration methods rather than patient needs.

Inefficiencies in Gas Flow Rates

Contributing author Professor Paul Ashley pointed out that gas flow rates varied wildly between 1 and 13 liters per minute, with no clear correlation to the age of the patient. The study suggests that many patients receive significantly more gas than required for effective sedation. High flow rates do not improve clinical outcomes or the patient experience, but they do drastically increase the environmental impact, presenting a clear opportunity for more precise, patient-centered administration.