Smoking in cars: Should it be banned?
16 November 2011 Last updated at 03:16 GMT
The British Medical Association thinks the smoking band should be extended to lighting up in car.
Research compiled by the BMA shows strong evidence that smoking in vehicles exposes non-smokers to very high levels of second-hand smoke.
This is because of the restrictive internal environment in vehicles, which expose drivers and passengers to up to 23 times more toxins than the environment of a smoky bar.
Dr James Cant, from the British Lung Foundation, carried out an experiment to measure the amount of toxins passed on to the passengers.