caption: Slide 4 of 21: You may not smoke, but did the previous occupants of your home indulge in the habit? Watch out for third-hand smoke, especially if you have rugs in your house. Even though you may not smell it, third-hand smoke can hang around in floors and walls for years and ultimately cause lung problems. Before moving into a home that once belonged to a smoker, be sure to give it a thorough cleaning. The same goes for any furniture or clothes you may have acquired from a smoker.