In England, dentists are being encouraged to use less nitrous oxide in order to help protect the climate.

A new study by University College London has analysed the use of nitrous oxide in dentistry in greater detail. Typically, nitrous oxide is used to sedate anxious patients before a dental procedure.

Even dental practices can contribute to climate protection.

Whether young or old, dental anxiety can occur at any age. Nitrous oxide is commonly administered for treatments such as fillings, crowns, or root canals. Patients do not consciously experience the procedure and only regain full awareness once the uncomfortable situation is over.

It is up to 273 times more harmful than carbon dioxide

However, nitrous oxide is a powerful greenhouse gas. Its impact is approximately 273 times more damaging than carbon dioxide

“Nitrous oxide plays an important role in dental care, particularly for children and adolescents, but it is also a potent greenhouse gas. Our study shows that its environmental effects vary greatly depending on the service provided, mainly due to differences in delivery and administration,” said the study’s lead author, Alexandra Lyne.

The research team analysed a dataset of 891 cases collected from 31 dental practices. They were able to determine an average emission of the gas.

A large amount is released directly into the atmosphere

For each sedation appointment, an emission of 28.6 kilograms of carbon dioxide equivalent (kg CO₂e) was recorded. This is roughly equivalent to a car journey of approximately 72.8 miles (117 kilometres).

Overall, the CO₂ footprint for a week of clinical nitrous oxide use ranged from 38.9 to 1,849 kg CO₂e. These large differences are attributed to the individual practices of each dentist.

The research team sees a significant need for action and expects worldwide positive effects for the environment.

The high value of 1,849 kg CO₂e is equivalent to the emissions of a 4,709-mile (7,578-kilometre) journey in a petrol car.

“Our recommendations include monitoring usage, reducing unnecessary waste, and standardising practice where possible. In this way, dental services can reduce emissions while maintaining patient care,” the team advised.

The analysis found that there are different methods of administration. A smaller proportion of practices used centralised piping systems. On average, waste was 30 percent higher at sites with piped delivery compared to those using gas cylinders.

Correct handling could save a significant percentage

Finally, the study highlighted large differences in nitrous oxide administration, with flow rates ranging from 1 to 13 litres per minute, without a clear correlation to the age of the patients.

This suggests that many patients may be receiving more gas than they actually need.

References of the news

Helmholtz Klima. (2026). Laughing Gas’ Role in Climate Change. Klimawissen. Klimadialog.

University College London. (2026). Call for dentists to reduce unnecessary nitrous oxide use. Latest News. Home.