Smoking bans linked to less second-hand smoke in children

Children who live in non-smoking homes are less likely to be exposed to second-hand smoke if their communities have smoking bans, a Harvard study reports today.

Laws that limit smoking in workplaces or restaurants have been tied to lower exposures in adults. Smoking bans in Massachusetts have also been credited for 600 fewer deaths from heart attacks each year since they were passed. A team of researchers from the Harvard School of Public Health looked at a more vulnerable population: children age 3 to 19.

Most second-hand smoke is found in the home. One out of 5 children live with smokers, but they also breathe in smoke elsewhere. Their smaller, still-developing lungs are more easily irritated than adults', and second-hand smoke has been associated with illnesses such as asthma and ear infections as well as sudden infant death syndrome, according to research cited in the study.

Using a national survey of more than 11,000 children and teenagers that measured signs of smoke exposure in the blood, the researchers compared children in smoking and non-smoking homes who lived in counties that had smoking bans with children who live in counties without such laws. None of the children themselves smoked.

More than half of all the children had detectable levels of cotinine, a byproduct of nicotine found in the blood. But the prevalence of cotinine was 39 percent lower among children who lived with nonsmokers in counties that had smoking bans compared to similar children in counties without such laws. For children in smoking homes, the bans made no difference in their cotinine levels.

Melanie Dove, lead author of the paper appearing in Pediatrics, said her next study explores respiratory diseases such as asthma and the impact of smoking bans.