Researchers demonstrate health risks posed by 'third hand' tobacco smoke

It seems popular opinion is relatively settled that breathing second-hand smoke is unhealthy, and that non-smokers who are exposed to it are at risk of illness. But the scientific evidence keeps piling up to support that theory, and even to extend the risks to another level: Third-hand Smoke!

Research into "third hand" smoke (residual tobacco smoke gases and particles that are deposited to surfaces and dust) has highlighted the potential cancer risk in non-smokers of non-dietary ingestion and dermal exposure to carcinogen N-nitrosamines and tobacco-specific nitrosamines (TSNAs) [Abstract].

Using a highly sensitive and selective analytical approach we have determined the presence of nicotine, eight N-nitrosamines and five tobacco-specific nitrosamines in forty-six settled dust samples from homes occupied by both smokers and non-smokers. Using observations of house dust composition, we have estimated the cancer risk by applying the most recent official toxicological information. Calculated cancer risks through exposure to the observed levels of TSNAs at an early life stage (1 to 6 years old) exceeded the upper-bound risk recommended by the USEPA in 77% of smokers' and 64% of non-smokers' homes.

[Ed. note: apparently, not only should you not stand next to someone smoking, but you shouldn't even walk through a place where someone has smoked, ever. Cancel my next trip to Paris, please.]