Third hand Smoke
Third hand smoke forms when particles from a cigarette or other tobacco-burning device seep into materials like hair, clothes, furniture, carpet and walls, and are absorbed. Nicotine residues will soak into a smoker's skin and clothing even if they smoke outside. The chemicals then undergo an aging process, which changes their chemical structure. Nicotine reacts with indoor air pollutants like nitrous acid to form carcinogens, or compounds that may cause cancer. The gas is then continuously re-emitted back into the air in a process called “off-gassing.”
Efforts to diffuse the smoke, like opening windows or using a fan, don’t prevent thirdhand smoke from forming or keep it from being inhaled, and the residue may give off harmful chemicals for years or even decades. “Thirdhand smoke is not a one-time thing,” Dr. Bechara says. “It’s actually a phenomenon that accumulates over time with increased exposure.” Normal cleaning methods also aren’t effective against the pollutants. Most of the time, replacing carpets or repainting walls are the only options.
Third-hand smoke is a potential health threat to children, partners, friends and family of smokers and workers in environments with smokers.