Doctors are to warn that the government is putting the health of millions at risk by not tackling the issue of passive smoking.

A report from the British Medical Association is expected to call for action to safeguard the health of non-smokers.

It will say that a substantial number of people are highly vulnerable to the adverse effects of passive smoking.

Our aim, for many years, has been for an end to smoking in workplaces and public places

Clive Bates, ASH

Eighty per cent of the population do not smoke. But a quarter live with a smoker, and millions are exposed to smoke fumes in public places.

Passive smoking has been linked to lung cancer, heart and circulation problems in adults.

The BMA is set to say those at risk include:

• 8m people with lung disease
• 2.1m with angina
• 1.3m who have had a heart attack
• 300,000 who have had a stroke
• 10.8m women of childbearing age
• 750,000 pregnant women

The BMA says children, who make up 20% of the population, are also at risk including the 1.5m who have asthma.

Passive smoking has also been linked with an increased risk of meningitis, cot death and chest infections in children.

Workplace smoking

Clive Bates of Action on Smoking and Health welcomed the BMA's involvement in the passive smoking debate.

He told BBC News Online: "Our aim, and theirs, for many years has been for an end to smoking in workplaces and public places.

"If they move that on by strength of argument and by the power of their position as doctors, then they will have done smokers, non-smokers and the NHS a great service.

"This is how you tackle cancer and heart disease."

Simon Clark, director of the smokers' rights organisation Forest, said: "I would hate to see them calling for a complete ban on smoking in public places.

"I don't believe smokers should be able to light up where and when they want. We support smoke-free areas because we believe in choice."