Regarding how long the electronic cigarette will leave the residue on the wall, there is no accurate time to indicate.
During the use of electronic cigarettes, there are some harmful substances in the released gas, such as formaldehyde. These harmful substances may be attached to the cigarettes, cigarette rods and walls of electronic cigarettes to form residues.
Although electronic cigarettes have reduced the harm of traditional tobacco, they still need to pay attention to the environment of electronic cigarettes, maintain the circulation of indoor air, and avoid harmful substances for too long in indoor air.