The British Medical Association (BMA) Scotland said there was “compelling” evidence for extending the current smoking ban to include vehicles.
It said more than 13,000 people in Scotland died each year because of smoking, almost a quarter of all deaths.
Research shows 26 per cent of adult non-smokers are exposed to second-hand cigarette smoke in cars, rising to 37 per cent of 18-24 year olds. In addition, 51 per cent of 8-15 year olds have been exposed to cigarette smoke while in a vehicle.
A paper from the BMA’s board of science said evidence suggested the levels of second-hand smoke in cars could “contribute to a serious health hazard for adults and children”. It said the concentration of toxins in a smoke-filled vehicle was 23 times greater than in a smoky bar.
It added that children and elderly people were particularly vulnerable to this. Children are at risk because they absorb more pollutants and have a less developed immune system, while elderly people are prone to respiratory problems.
Dr Dean Marshall, chairman of the BMA’s Scottish GP committee, said: “Every year in Scotland, almost a quarter of all deaths are caused by smoking. That equates to over 13,000 deaths. This figure increases to a shocking six million worldwide.
“Scotland made a huge step forward in the fight against tobacco by banning smoking in all enclosed public places, but more can still be done. We are calling on the Scottish Government to take the bold and courageous step of banning smoking in private vehicles. The evidence for extending the smoke-free legislation is compelling.”
A Scottish Government spokesman said: “While we have no plans to extend the smoke-free laws to private cars, the Scottish Government is conscious that private cars are now one of the main places for exposure of children to second-hand smoke.
“In developing our refreshed national tobacco control strategy for publication next year, we will consider what further steps might be taken to protect children from the risks posed by second-hand smoke.”