One in ten children in the North East are still being exposed to secondhand smoke in their home.
The new figures come as a new campaign by anti-smoking group Fresh - supported by the British Lung Foundation - is launched today.
The campaign - Secondhand Smoke is Poison - warns that smoking in the home exposes smokers, their children and others in the family to harmful levels of toxic chemicals such as carbon monoxide, benzene and cyanide.
These creep from room to room and can linger for up to five hours.
Experts say 85% of secondhand smoke is invisible and odourless and many people are not aware that simple steps, like opening a window, smoking by the back door or in another room does little to protect children and non-smoking adults.
Secondhand smoke causes numerous health problems in infants and children, raising the risks of more frequent and severe asthma attacks, respiratory infections, ear infections, and even meningitis and sudden infant death.
Children are more vulnerable because they breathe faster than adults so inhale more of the poisons.
Ailsa Rutter, director of Fresh, said: “When someone lights a cigarette they are setting fire to a cocktail of chemicals and industrial pollutants.
“These not only go into the lungs and around the body, but into the air as secondhand smoke.
“Every parent wants to protect their children. Many smokers think they’re already doing enough by opening a window or smoking at the back door, without realising how poisonous secondhand smoke spreads around the house and lingers long after you can see it or smell it.”
The Royal College of Physicians estimate that secondhand smoke exposure in UK children each year caused over 20,000 cases of lower respiratory tract infection, 120,000 cases of middle ear disease, at least 22,000 new cases of wheeze and asthma, 200 cases of bacterial meningitis, and 40 sudden infant deaths - one in five of all cot deaths.
Dr Venkatesan Kannan, consultant paediatrician with South Tyneside NHS Foundation Trust, said: “Breathing in secondhand smoke is harmful to people from all age groups, but children are especially vulnerable as their lungs are still developing and they breathe faster than adults, so inhale more of the harmful poisons.
“There is no safe level of exposure.”
“We see the effects of this on hospital wards too often. Most parents take this seriously when they realise that their smoking may be making their child unwell and want to do something positive about it.”
For more informaton, go to smokefreefamilies.co.uk.