Third-hand smoke harms
05:55 AM Feb 10, 2010
WASHINGTON - You know inhaling someone else's smoke is bad for you. Now a US study says third-hand smoke - tobacco residue clinging to surfaces - is also bad for you.
When a cigarette burns, nicotine is released in the form of a vapour that condenses on indoor surfaces, such as walls and furniture, where it can linger for months, said the study, published in the Proceedings of the National Academy of Sciences.
"When this residual nicotine reacts with ambient nitrous acid, it forms carcinogenic tobacco-specific nitrosamines, or TSNAs," said author Hugo Destaillats.
The most likely human exposure to TSNAs is through either inhalation of dust or the contact of skin with carpet or clothes - particularly dangerous for infants and toddlers.
Smoking outdoors does not eliminate the hazard. "Nicotine residues will stick to a smoker's skin and clothing ... and spread everywhere," said co-author Lara Gundel. AFP
