According to the American Thoracic Society, harmful chemicals from vaping may stay in the air long after people stop vaping.
According to a 2021 study, exhaled vape particles can persist in the air and mix with the environment indoors. They can also increase concentrations more than 3.6 meters away from the original vaping source.
In a 2020 study, researchers looked at levels of vape chemicals in the air in vape shops during open and closed hours. Concentrations of nicotine, formaldehyde, and acetaldehyde were 3–4 times higher when the shops were open than when they were closed.
Nicotine may also stay on clothes and surfaces, resulting in possible thirdhand vape exposure.