Kids can’t escape second-hand smoke

U. ROCHESTER (US) — Children living in apartments are exposed to second-hand smoke even when no one smokes inside their own unit.

The study, published online in the journal Pediatrics, strongly suggests that housing type contributes to children’s exposure to tobacco smoke, despite the best intentions of parents.

Children exposed to second-hand tobacco smoke are at greater risk for a variety of illnesses, including respiratory infections, asthma, and sudden infant death syndrome.

For the current study, researchers measured blood levels of cotinine, a chemical commonly used to test for tobacco exposure.

Overall, using the most sensitive cutoff for tobacco smoke exposure, more than 84 percent of children in multi-unit housing had been exposed to tobacco smoke, compared to almost 80 percent of children living in attached houses and 70 percent of children in detached houses. At every cutoff level of cotinine, children living in apartments had higher rates of exposure.

“Parents try so hard to protect their children from dangers, such as tobacco smoke,” says Karen Wilson, assistant professor of pediatrics at the University of Rochester.

“It’s surprising to see these results and realize that too many parents have no control over whether their children are exposed to second-hand smoke in their own homes.”

Controlling for other factors such as poverty and age, children living in apartments had an increase in cotinine of 45 percent over those living in detached houses.

While some of the tobacco exposure may have come from family members who only smoke outside, but carry in tobacco residue on their clothes, researchers suggest this is unlikely to explain all of the difference since there are many more exposed children than adult smokers.

Instead they conclude tobacco smoke may have seeped through walls or shared ventilation systems. Earlier studies have shown that tobacco smoke contaminates non-smoking units of multi-unit dwellings.

The study analyzed data from more than 5,000 children ages 6 to18 in a national database (National Health and Nutrition Examination Survey 2001-2006) to see if there was any relationship between their smoke exposure and their housing type.

Cotinine levels were highest for children who were younger than 12, black and living below the federal poverty level.

Previous studies have shown that children with cotinine levels indicating even very low amounts of tobacco smoke exposure have delayed cognitive abilities and decreased antioxidant levels.

“This study is an important piece of evidence supporting universal smoke-free multi-unit housing,” says Jonathan Winickoff, associate professor of pediatrics at Harvard Medical School.

“This research will help promote the notion that it is never acceptable to smoke indoors, even in your own unit, because the smoke get into the bodies of children in other units.”

The authors also stress the importance of making sure that tobacco cessation resources are provided for smokers whose buildings become smoke-free.

“Hopefully this research and the movement towards smoke-free housing will open up programs and opportunities for more folks to quit smoking. Promoting the use of the free quitlines in every state is a great way to facilitate these efforts,” Wilson says.

The study was funded by by the Julius B. Richmond Center of Excellence of the American Academy of Pediatrics, through a grant from the Flight Attendant Medical Research Institute.

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