Vaping

[ErmWhatWasIDoing]

My 20 year-old DD Vapes In her bedroom. Her bedroom smells stale and whilst some might disagree, I can prove that the vapour is staining her walls. I cleaned her (fairly new) carpet recently and the residual water was dirty brown. I absolutely detest smoking or vaping of any kind and certainly don't want it in my house. I have talked to her about this, pointing out the health implications and asked her not to vape in the house but she continues to do so.
What would you do in this situation?

It's your house, so you can certainly ask. However, she is an adult, and it's her room. The smell of vaping disperses pretty quickly and doesn't impact anyone else. In addition, can't she clean her own room?

She could use nicotine pouches in the house, and vape outside. Switching to a mint flavour is less offensive. It takes many years of vaping to stain a wall, so I don't think that's a thing.