If you can’t quit smoking for the sake of your own health, consider the health of your dog or cat: Your pets not only breathe in your cigarette smoke (secondhand smoke), they also take up residues of the smoke particles left on skin, clothing, carpets, curtains, and furniture (thirdhand smoke), according to the FDA.
Pets may be exposed to a lot of thirdhand smoke, since they are probably home most or all of the time, and they spend more time low to the ground where the particles land and concentrate in dust. They also can get residues on their fur, which they ingest if they groom themselves.
Dogs with longer noses (which trap more particles) have double the risk of nose cancer, while shorter-nose dogs have a higher risk of lung cancer (more particles go to the lungs). Cats who live with smokers have higher rates of lymphoma and mouth cancer. The FDA warns that smoking can also harm pet birds, fish, and guinea pigs.
Also see Can Pets Help You Live Longer?