Cannes leads the way: municipal police test drivers for nitrous oxide
Cannes has become the first city in France to equip its municipal police with nitrous oxide detectors. Ten tests have already been carried out, one of which came back positive.
Cannes pioneering the fight against "laughing gas" at the wheel
According to Google News FR — Crime (fr), Cannes has become the first city in France to equip its municipal police with nitrous oxide detectors. Since Thursday 20 August, three devices measuring the concentration of this gas in exhaled air have been operational, and initial results have already emerged.
During the night from Friday to Saturday, ten motorists were subjected to the test. One of them tested positive: his vehicle was immobilised for more than an hour, until a second negative test. A passenger was also issued a fine for consumption, and three others for possession of canisters.
A test triggered by a road traffic offence
The tests are not systematic. They only take place when a driver is stopped after committing an offence or adopting driving that is deemed dangerous.
"When a vehicle runs a red light, crosses a continuous line or drives dangerously, we stop it. After confirming the offence, we can carry out the test," explains Yves Daros, director of Cannes municipal police.
A detector manufactured in Aix-en-Provence
The device used is designed by the company Olythe, based in Aix-en-Provence. Its operating principle is similar to that of an electronic breathalyser.
"You blow for three to four seconds and the result immediately shows the concentration of nitrous oxide in the exhaled air," explains Guillaume Nesa, co-founder of the company.
Nesa also cites the initial results of a study conducted by Aarhus University in Denmark: 85 per cent of participants still showed detectable traces four hours after consumption. The university confirms that the gas remains detectable for several hours in exhaled air, whilst clarifying that the device is a screening tool, not legal evidence.
Serious effects on driving ability
Dizziness, loss of reflexes, perceptual disturbances: nitrous oxide can seriously impair a driver's faculties. "People pay less attention, take more risks and sometimes no longer have the reflexes needed to avoid an accident," warns Professor Faredj Cherikh, psychiatrist-addictologist and head of the addiction medicine department at Nice University Hospital.
Cherikh acknowledges the deterrent value of these checks, but considers that they must be part of a broader approach: "Prevention is key. We need to inform young people who have used it and quickly offer them a medical assessment."
The phenomenon is far from marginal in Cannes: nearly 11,000 canisters were collected in the city in 2025.
A 150-euro fine pending the RIPOST law
For now, offenders face a 150-euro fine under municipal bylaws. Cannes town hall says it is thereby anticipating the future RIPOST law, whose national provisions provide for up to three years' imprisonment and a 9,000-euro fine for driving after manifest consumption of psychoactive substances. A decree must still specify the list of products concerned.
Furthermore, the general ban on the sale of nitrous oxide to private individuals will come into force on 1 February 2027.
A local context marked by several cases
This initiative comes in a tense local context surrounding nitrous oxide. A 25-year-old man was recently sentenced to six months' imprisonment after being arrested in the Musicians neighbourhood in Nice, in possession of canisters that he had been selling from a scrapped car converted into a point of sale.
In December 2025, Nice police court had already summoned four people for breaching the prefectural bylaw governing the sale of this gas. As early as 1 August, Cannes town hall had announced a ban on the sale of canisters to all private individuals, both adults and minors.
Source: Google News FR — Crime (fr)