My mom believes the odor tobacco, produces, not the smoke, is harmful by itself... Is it true?

You smell something when particles of some chemical substance hit receptors in your nose. So the smell is really the same thing as the smoke although it wouldn't be as concentrated. If you live in a place where you smell the smell of smoke constantly it could certainly affect your health.

Smoking and Christianity don't mix. This should be obvious. Smoking It is a defilement of the body. Having faith requires more than just believing. Like James said, even the demons believe, and they are fearful. You must exercise faith, which requires action, and a willingness to turn your life around. That includes quitting smoking. It's interesting that you chose smoking of all things to slam us on, when most people agree that smoking is bad for your health. It is also interesting to note that if a person seeking baptism quits smoking to achieve that, you see that as something negative. That makes no sense. Here is the scripture behind the principle: 2 Corinthians 7:1 - Therefore, since we have these promises, beloved ones, let us cleanse ourselves of every defilement of flesh and spirit, perfecting holiness in God’s fear. Smoking is a defilement of the body. Hope this helps.

Incorrect.

Take an unlit cigarette and smell it. It smells like a cigarette... because it is a cigarette.

You can tape that cigarette to your nose and sniff at it for 60 years, but you're not gonna develop any lung conditions because you're not inhaling smoke... you're just smelling cigarrettes.

Simultaneously, the odor for cigarettes is intense, and caps off after a certain point. Have someone smoke in a room. Walk in while the smoke is fogging the air and smell the air. It's strong. Walk out, wait 10 minutes. Walk back in while it's clear and smell the air. It's still strong... yet the air is clear.

When you walk by someone on the sidewalk smoking a cigarette and get a whiff of smoke, the odor is just that, odor. It's unpleasant. Farts are unpleasant, and inhaling methane lately will kill you but that doesn't mean passing by someone who farted outdoors and then smelling it is gonna give you methane poisoning for crying out loud.