Tobacco.org

Thirdhand Smoke Forms Cancer-Causing Residue Indoors That Lasts 

Tobacco smoke contamination lingering on furniture, clothes and other surfaces, dubbed thirdhand smoke, may react with indoor air chemicals to form potential cancer-causing substances, a study found.

After exposing a piece of paper to smoke, researchers found the sheet had levels of newly formed carcinogens that were 10 times higher after three hours in the presence of an indoor air chemical called nitrous acid commonly emitted by household appliances or cigarette smoke. That means people may face a risk from indoor tobacco smoke in a way that's never been recognized before, said one of the study's authors, Lara Gundel.

Previous research has shown that secondhand smoke, which is inhaled by nonsmokers exposed to fumes from cigarettes, raises the risk of cancer and heart disease. More research is needed to identify the potential health hazards of thirdhand smoke, Gundel said. Overall, tobacco use causes 20 percent of all cancer deaths, according to the study published in today's Proceedings of the National Academy of Sciences.

"We have considered that nicotine on surfaces has been pretty benign up to this point. It turns out we shouldn't say that now," said Gundel, a staff scientist at Lawrence Berkeley National Laboratory in Berkeley, California, in a Feb. 5 telephone interview. "People can be exposed to toxins in tobacco smoke in a way that's never been recognized before."

Jump to full article »