A new study has confirmed smoking parents damage the health of their young children.
Researchers at the University of Bristol found kids exposed to second-hand smoke around the house had raised levels of cotinine, which comes from nicotine, particularly those whose mothers smoked in excess of 10 cigarettes a day.
Cotinine levels in children as young as seven were four times greater than in kids of mothers who did not smoke, and five times higher once the children celebrate their 15th birthday. The levels were similar to those in teens who occasionally smoke.
Passive smoking raises the chance of heart disease, lung cancer and respiratory disease.
Researchers said the findings highlight the importance of cutting smoking in private homes and cars. The study was published in the journal Nicotine and Tobacco Research .
Lead author Alex Stilby said: "We have found that the children of mothers who smoke have elevated cotinine levels, indicating clear evidence of passive smoking exposure.
"This provides a strong public health message about the risks to children if there are adults smoking in the home. Our research shows that the risks apply to older children just as much as to younger ones."
Copyright Press Association 2013