A new British study has found that drivers who write and send off text messages are more impaired than those who've been drinking or are high on pot.

The study, commissioned by the Royal Automobile Club (RAC) Foundation, found that composing text messages while driving had a negative impact on all key measures of driving performance.

Researchers, who released the study this month, watched drivers between the ages of 17 and 24 on a driving simulator and discovered that:

• The reaction times of texting drivers deteriorated by over one-third (35 per cent).
• This was worse than alcohol at the legal limit, which slowed reaction times by 12 per cent.
• Even drivers under the influence of cannabis fared better than texting drivers, with reaction times that were 21 per cent slower than sober drivers.
• Drivers drifted out of their lane more often if they were texting. Steering control was 91 per cent worse, compared to 35 per cent worse when under the influence of cannabis.

In a press release outlining details of the study, the RAC Foundation said that text messaging while driving poses an "unacceptable risk," especially when it involves young drivers.

"Despite the danger, 48 per cent of U.K. drivers aged 18 to 24 admit to using short message services (SMS) whilst driving -- a group already at much higher risk of being involved in a crash," said the media release.

The RAC Foundation is calling for a high-profile education campaign to raise awareness among young people in Britain about the dangers of text messaging and driving.

Prof. Stephen Glaister, director of the RAC Foundation, said that study participants were almost unanimous in their view that drinking and driving was riskier than texting while driving.

"Yet this research clearly shows that a motorist who is texting is significantly more impaired than a motorist at the legal limit for alcohol," Glaister said in the press release.

"No responsible motorist would drink and drive. We need to ensure that text devotees understand that texting is one of the most hazardous things that can be done while in charge of a motor car."

The study's authors said that text messages that normally took about 22 seconds to compose at a desk took almost three times as long when the person texting was behind the wheel.

"Writing a text message had the biggest impact on reaction times, increasing them from 1.2 seconds to 1.6 seconds. At motorway speeds, this would mean travelling an additional three car lengths before beginning to brake. Some participants missed the visual trigger completely," the press release said.

Researchers said that drivers are distracted in three ways if they're writing and sending text messages:

• the work of composing the text takes the mind off the road
• using the phone's keypad means that only one hand is on the wheel, limiting control of the vehicle
• the driver's eyes are on the phone and not on the road ahead

Here in Canada, Quebec, Nova Scotia, and Newfoundland and Labrador have laws limiting text messaging or use of cellphones while driving.

A University of Toronto study that looked at the cellphone records of nearly 700 Toronto drivers who had been in car crashes found that they were four times more likely to get into an accident while on their phones.