Effects of passive smoking evident in children
Children as young as seven are showing the physical effects of their parents' smoking habits, a study has found.
Those subjected to second-hand smoke at home had elevated levels of cotinine – a by-product of nicotine – in their systems.
The levels were particularly high in children whose mothers smoked 10 or more cigarettes a day.
Cotinine levels in the seven-year-olds were four times higher than in children of non-smoking mothers, research found.
And by the time the children had reached 15, the levels had risen to five times higher.
The elevated levels at ages seven and 15 are comparable to those in teenagers who are infrequent smokers.
Passive smoking is known to increase the risk of heart disease, lung cancer and respiratory disease.
Researchers at the University of Bristol say the research, published yesterday, provides new evidence of the need to reduce smoking in private homes and cars.
Alex Stilby, lead author of the research, published in the journal 'Nicotine and Tobacco Research', said children and teenagers were affected by second-hand smoke.
He said: "We have found that the children of mothers who smoke have elevated cotinine levels, indicating clear evidence of passive smoking exposure.''
The research involved 3,000 children when they were aged seven, and 2,000 when they reached 15. They were taking part in the 'Children of the 90s' study.
It found elevated levels of cotinine in the blood of children at both ages were strongly related to whether the mother smoked and if so, how heavily – providing "clear evidence" of passive smoking.
A study by the Royal College of Physicians showed that about 17,000 children in the UK are admitted to hospital every year because of illnesses caused by second-hand smoke.