Study Finds Kids At Risk Of Smoke Exposure Even In Smoke-Free Areas

If you’ve ever rented a car or stayed in a hotel room previously occupied by a smoker, you’ve probably already smelled signs of thirdhand smoke.

When it comes to the dangers of smoking, most parents are familiar with the health risks associated with firsthand (smoking themselves) and secondhand (exposure to others) smoke.

However, a related, and often ignored, hazard is thirdhand smoke. Thirdhand smoke refers to the exposure of children to environments in which people smoke. We may forget residue from cigarette smoke remains on exposed surfaces, such as clothing, carpets and furniture …even long after the cigarette has been extinguished.

More and more research is stacking up to show the dangers of thirdhand smoke. A study published this week in the journal Science Advances explains the way tobacco smoke from outside finds its way into a nonsmoking classroom. The research conducted at Drexel University found that thirdhand smoke can attach to clothes, hair and other surfaces, allowing the pollutants to find their way into non-smoking buildings, such as classrooms. The smoke coats the classroom’s surfaces and the hazardous chemicals can then become airborne and circulate throughout the building because of air conditioning.

“While many public areas have restriction on smoking, including distance from doorways, non-smoking buildings and even full smoking bans on campus for some universities, these smoking limitations often only serve to protect non-smoking populations from exposure to secondhand smoke,” said Michael Waring, PhD, an associate professor in Drexel’s College of Engineering, and a co-author of the research. “This study shows that thirdhand smoke, which we are realizing can be harmful to health as with secondhand smoke, is much more difficult to avoid.”

Previous research on mice has linked thirdhand smoke to the risk of lung cancer and another study found a link to liver damage and diabetes.

If you are a non-smoker, you surely recognize immediately the odor created by the residue from tobacco smoke that clings to almost everything in the room. If you smell cigarette smoke in a room, car or on a friend, it means you and your children are being exposed to thirdhand smoke. Prolonged exposure to such circumstances can cause serious health problems. Residue that remains on surfaces includes heavy metals, carcinogens and even radioactive materials. Young children, especially if they’re crawling or playing on the floor, are at risk of either ingesting the residue or getting it on their hands and feet.

“This residue may react with other substances, forming toxic compounds that can be breathed in or absorbed through the skin,” said Don Wilson, M.D., a pediatric endocrinologist and an Endowed Chair of Cardiovascular Health and Risk Prevention at Cook Children’s. “The developing brain is uniquely susceptible to extremely low levels of toxins.”

Perhaps the worst part about thirdhand smoke is that it is hard to eradicate. Studies have found that thirdhand smoke accumulates in smokers’ homes and remains even after homes have been vacant for two months. A study found that heavy smoke residue remained on walls and carpet in casinos six months after smoking was banned.

 “The residue from cigarette smoking cannot be effectively removed by ventilation, scrubbing with an alkaline soap or cleaning carpets which have had long-term exposure… Bottom line, removal of tar and nicotine from cigarette smoking is nearly impossible,” Dr. Wilson said.

Although there is no direct proof yet that thirdhand smoking causes cancer in humans, studies have found it contributes to emphysema, asthma and bronchitis. Because a child’s body is still developing, he or she is more likely to be affected by thirdhand smoke. Children exposed to smoke are at increased risk for multiple serious health effects including asthma, respiratory infections, decreased lung growth and sudden infant death syndrome (SIDS).

For parents who don’t smoke or have quit – congratulations. You have made a wise choice for yourself (firsthand smoke) and for your children (secondhand and thirdhand smoke).

“For parents who still smoke, one of the best investments you can make for yourself and your child is to stop,” Dr. Wilson said.

Pediatricians can assist parents by providing counseling about the dangers of exposure, helping the parents or other family members quit smoking or by providing support for community policy change. If you’ve moved into a new house where the previous owners may have smoked, go ahead and redecorate; repainting the walls and replacing the carpets could save your child from suffering down the road.