Academic professor Wayne Hall says young Australians should have a zero blood alcohol requirement attached to their driver's license until they turn 21 at least, in a bid to reduce road toll.

The move would prevent dozens of road fatalities and serious injuries from alcohol-associated accidents each year, said Prof Hall from the Centre for Clinical Research at the University of Queensland.

He said he supported an approach to the model applied in some American states where it was illegal to drink at all until age 21, though this was unlikely to be accepted well in Australia.

That would be a huge change in policy, and likely to be resisted by young people and the alcohol industry and if it were to get up, it probably wouldn't be well complied with, said Prof Hall.

... there may well be a case to go to 25, because that's the age at which young people are especially likely to drink heavily and get involved in motor vehicle crashes.

Fewer alcohol-related crashes involving young people have been observed in US states in which the minimum legal drinking age is 21 compared with those American states where 18 year-olds can drink legally.

Based on the calculation made by Prof Hall, 17 fewer deaths would have occurred in 2003 among those aged 18 to 21 years, if zero blood alcohol limits are applied to Australian drivers up to age 21.

He also said, 50 deaths would have been prevented if the requirement is imposed on drivers up to age 25, and rates of serious injury would significantly decrease.

You're looking at another 12 to 20 serious injuries for each death, so there's a lot of young people who wouldn't have been seriously damaged and spending lots of time in hospital, said Prof Hall.

The change, he said, could be seen in the same light as the universal roll-out of seat belt laws and setting the blood alcohol limit for fully licensed drivers at .05.

Licensing system in Victoria has already set a minimum age of 22 for a driver to obtain full license, but other states are generally more lenient about when a young driver can legally have alcohol in their system.

There would not be a lot of additional enforcement costs because police are already random breath-testing drivers, said Prof Hall.

The only additional thing would be to check their age when they were breath-tested.