There are a lot of habits we find ourselves doing as we get older. For some of us these habits include eating, sleeping, drinking, facebooking... For others, this includes smoking.
According to AMVA, owners who smoke, especially in the same areas as their pets, are 3x more likely to have dogs and cats with lung and nasal sinus cancer and cats with lymphoma.
Dogs and cats noses are much stronger than a humans. A nonsmoker can tell always tell a smoker from a nonsmoker because the smell stains your clothes. Imagine what it is like for your pet. They are breathing it all in.
It is 10x more likely if your dog is brachycephalic. This means they have a shorter muzzle than your average dog. That means they have shorter muzzles, shorter airways, tighter airways. They run out breath a lot faster than nonbrachycephalics. Brachycephalic dogs include
other flat faced dogs/cats.
It is best to have your pet away from your smoke because the habit is hard to break and you don't want to risk your pets life. Try taking an extra set of clothes with you if you know you're going to smoke. This way your dog doesn't smell it as strong when you arrive home.