Many parents across the globe are failing to protect their children from secondhand smoke, new research has found.
Exposure to secondhand smoke has been shown to increase the risk of many illnesses including cancer. Children, whose bodies are still developing, are particularly vulnerable. Secondhand smoke increases the risk of cot death, asthma and chest infections.
The study from the Johns Hopkins Bloomberg School of Public Health in the US found that 82 per cent of parents who smoked said that they did so around their children.
The findings are based on an analysis of people in 31 countries and show that secondhand exposure, particularly among children, is a global concern.
The researchers analysed household air and samples of children's hair and found levels of nicotine that confirmed those living with a smoker were generally subjected to high levels of secondhand smoke.
Published in the American Journal of Public Health (AJPH), the study showed that concentrations of nicotine in the air were 17 times higher in households with a smoker than those without.
Concentrations were 12.9 times higher in households where smoking was permitted indoors than in homes where residents chose to smoke outdoors.
The samples of children's hair showed that 78 per cent of those living with a smoker and 59 per cent not living with a smoker contained nicotine. Levels of nicotine in the hair samples tended to rise in line with the concentration of nicotine in the air.
Lead author Dr Heather Wipfli, project director at the Bloomberg School's Institute for Global Tobacco Control, said: "Our research clearly shows that parents are failing to protect their children from secondhand smoke exposure, perhaps because they are unaware of the risks.
"The results highlight the need to improve public awareness of the importance of going outside to smoke to limit the exposure to children living in the home."
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