Scientists have long known the health hazards of being exposed to second-hand smoke. But a new study finds that third-hand smoke – defined as second-hand smoke that sticks to surfaces – can have a number of serious negative health impacts as well.
The study was carried out by researchers at the University of California, Riverside. In the study, researchers exposed mice to third-hand smoke in environments simulating those in which humans are exposed to it. The study showed that third-hand smoke exposure caused organ damage, less efficient skin healing, and hyperactivity in the mice.
“There is still much to learn about the specific mechanisms by which cigarette smoke residues harm nonsmokers, but that there is such an effect is now clear," researcher Manuela Martins-Green said. “Children in environments where smoking is, or has been allowed, are at significant risk for suffering from multiple short term and longer health problems, many of which may not manifest fully until later in life."
Let’s look at a few of the study’s specific findings.
In the liver, third-hand smoke exposure was found to increase lipid levels and non-alcoholic fatty liver disease, which is a precursor to cirrhosis and liver cancer. In the lungs, exposure to third-hand smoke caused increased collagen production and inflammation. Exposed mice with wounded skin took much longer to heal than mice that were not exposed to the smoke. Finally, exposed mice displayed notably hyperactive behavior.
All together, the findings present troubling information on the dangers of third-hand smoke.
“The latter data, combined with emerging associated behavioral problems in children exposed to second- and third-hand smoke suggests that with prolonged exposure, they may be at significant risk for developing more severe neurological disorders," Martins-Green said.
Science Daily notes that children who live with one or two parents who smoke in the home miss 40% more school days due to health problems than children who live in smoke-free homes.