If smoked indoors, the cold cigarette smoke settles in furniture, curtains, and wallpaper for months. From there it also re-enters the human body. Airing out doesn't help much with this tobacco residue problem, a study from the U.S. shows
If you've had a long party at home with lots of smoking guests, the first thing you'll do the next morning is tear open all the windows in your smoky apartment to get rid of the unpleasant odor. Because the cold tobacco smoke settles everywhere.
The bad news, however, is that airing your rooms once is not nearly enough to clean them up and reduce nicotine exposure to zero.
Tobacco residues on surfaces degrade very slowly
Researchers at the prestigious San Diego State University in the United States conducted a study to determine how long cold tobacco smoke ("third-hand smoke") lasts, abbreviated THS) in rooms and on surfaces where there has been heavy smoking.
To do this, scientists studied a California casino where people smoked daily for many years and took samples at eight different locations – twice before and six times after the smoking ban, which was enacted in 2014.
After the smoking ban was enforced, nicotine levels in indoor air dropped rapidly, but levels on surfaces and in soil dust decreased much more slowly. Here, researchers found nicotine, tiny particles and tobacco-specific nitrosamines even months later.
People ingest tobacco residues
In the second step of their study, the researchers wanted to know the amount of these tobacco residues people ingest. Using modern analytical techniques, the scientists found that here, too, levels dropped significantly after the smoking ban was introduced.
But even six months later, the non-smoking subjects were found to have higher THS levels on their fingers and in their urine after a four-hour visit to the casino than non-smoking subjects who had not been to the casino. Tobacco residues adhere to surfaces for many years. Can thereby penetrate deeply into the materials. Rooms in which a lot of smoking has taken place can therefore only be freed from tobacco residues by intensive surface cleaning or by changing the furniture, carpets and wallpaper.
The researchers published the results of their study in the journal Tobacco Control.
Are there possible long-term effects?
Tobacco smoke contains many toxic and carcinogenic pollutants that are rapidly absorbed into the body through the lungs. However, little research has been done on the long-term health effects of ingesting cold tobacco smoke.
However, the German Cancer Research Center (DKFZ) recommends in its guide to cold tobacco smoke that contact should be avoided. In addition, smoking should not be permitted in enclosed areas.