The dangers of passive smoking are highlighted by a new government awareness campaign that is launched this week.
The adverts, which will be used on TV, online, in the press and on posters, illustrate the fact that 85 per cent of the cancer-causing toxins in cigarette smoke are invisible and odourless.
"Smoking is harmful not just to smokers but to the people around them," said public health minister Caroline Flint.
"What this new campaign brings home very clearly is the full impact of second-hand smoke."
The campaign comes just weeks ahead of the launch of smokefree legislation for Wales on April 2nd and months ahead of similar legislation in England in July.
Jean King, director of tobacco control at Cancer Research UK, said: "The effects of smoking are devastating. Every day in the UK 300 people are killed by a smoking related disease.
"We know that the vast majority of smokers want to quit. And we hope this campaign will encourage many to give up for good as well as make non-smokers feel justified in asking other people not to smoke around them.
"England goes smokefree on July 1st and the new law will give smokers a golden opportunity to stop. Quitting is the best present you can give yourself and your loved ones."
Previous research has shown that tobacco increases the risk of lung cancer by around 24 per cent and heart disease by 25 per cent.
The campaign follows a Department of Health campaign earlier this year, illustrating the dangers of tobacco with smokers 'hooked' by their need for a cigarette.
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