Public buildings in the United States are smoke-free for the most part because there is general consensus that exposure to the smoke from another person's tobacco product could cause respiratory problems in susceptible people such as asthmatics and children. Hotel rooms have the smoke-free option, and even bars are mostly non-smoking these days.
But what if it's not enough? Research has shown that so called "third-hand" smoke, the residue of exhaled second-hand smoke, is actually quite a health hazard that must be addressed. So simple banning of smoking in buildings will not necessarily protect the rest of us from what comes in on a smoker's skin and clothing after they smoke outside or in their car.
In 2010, a study by a group of environmental scientists showed that when residual nicotine reacts with other chemicals (mainly nitrous acid), it forms cancer-causing agents known as TSNAs, or tobacco-specific nitrosamines. Nitrous acid is found naturally in the environment as well as in association with gas appliances indoors. This interaction has the effect of producing potent carcinogens.
All non-smokers are familiar with that stale odor in a house, hotel room or car where a smoker has preceded them even if it has been days, weeks or months since anyone has actually lit up. It can be nauseating and annoying, but more importantly, it can contribute to disease with repeated exposure over time - this environmental science study confirms that potential.
Infants and toddlers are potentially more at risk for exposure to these toxins than the rest of us - we hold a baby close to our chest where the residue of a recently extinguished cigarette still clings to our clothing; we let our toddler crawl on the carpet that has years of toxic chemical accumulation....no one wants to cause harm to a child, and most smokers would have absolutely no idea that this silent exposure is happening.
The current policies of banning smoking within so many feet of a building are at least better than no policy at all, but unless there is some way to decontaminate clothing and objects that accompany the smoker through their day, the rest of us may not escape at least some exposure to the third-hand carcinogenic agents.