The British Medical Association is calling for a total ban on smoking in cars to protect people from second hand smoke.
The association says Britain's current ban on smoking in public places should be extended to cars in light of the dangers, the BBC reports.
A spokesperson Vivienne Nathanson says passengers in cars may be exposed to levels of toxins more than 20 times higher than those found in a smoky bar.
She says cars are a restricted environment.
"Air gets concentrated in there and if somebody is smoking in a car, the people in that car - both at the time and later - are going to get very high doses of the cancer causing agents that are in cigarette smoke," she says.
She says the ban should be put in place immediately to save lives.
However, pro-smoking lobby group Forest says a ban would be an infringement of individual liberties.
