I read it. It's not compelling.

The first cited research regarding DNA damage is a dead link. It says "error: this is not a published article" or something like that.

The second cited research is an abstract claiming that 20% of mice developed lung cancer after being exposed to vape smoke for 9 weeks. The methodology is blocked behind a paywall, but I'm betting they concentrated trace components and blasted mice with it for two months straight. This isn't very informative; if I concentrated the carcinogens found in normal city air, I could probably achieve a higher kill rate.

A better example of this strategy would be if I blasted mice with extremely high intensity UV radiation to prove that the sun was dangerous. Sure, 90% of mice would quickly get skin cancer, but it doesn't tell us how harmful the sun is in real scenarios. Blasting an animal with a lifetime worth of sun in an hour is more dangerous than gradual exposure.

Tobacco the plant has a host of carcinogens. No matter where you put tobacco -mouth, lungs, bladder, nose, ass, wherever-it causes cancer. The article's claim that nicotine causes lung cancer but nicotine gum is safe is pretty ridiculous.

Source: I'm a chemist. Part of my schooling was making mundane results appear as sensational as possible.

I suspect it has to do with repeated inhalation of something that is not air, but I'm not a doctor nor a scientist so this is purely vibes