Now scientists are worried about another cigarette-related phenomenon: thirdhand smoke. It’s real, and it’s ubiquitous. Without knowing it, indoor smokers have left a toxic legacy that continues years after their last butt was stubbed out.
Researchers now know that residual tobacco smoke, dubbed thirdhand smoke, combines with indoor pollutants such as ozone and nitrous acid to create new compounds. Thirdhand smoke mixes and settles with dust, drifts down to carpeting and furniture surfaces, and makes its way deep into the porous material in paneling and drywall. It lingers in the hair, skin, clothing, and fingernails of smokers—so a mother who doesn’t smoke in front of her kids, smokes outside, then comes inside and holds the baby is exposing that child to thirdhand smoke. The new compounds are difficult to clean up, have a long life of their own, and many may be carcinogenic.
One of those compounds, a tobacco-specific nitrosamine known as NNA, damages DNA and could potentially cause cancer. “Thirdhand smoke is harmful to our genetic material,” Bo Hang, a scientist at the Lawrence Berkeley National Laboratory in California, said at a news conference this week at the annual meeting of the American Chemical Society, where the research was presented. “And the contamination becomes more toxic with time.”