Inhaling harmful chemicals in vaping products can cause irreversible lung damage (they cannot be cured), lung disease and, in some cases, death. Some chemicals in vaping products can also cause cardiovascular disease and biological changes that are associated with the development of cancer. Instead of bathing lung tissue with a therapeutic spray, such as a nebulizer does, vaping coats the lungs with potentially harmful chemicals. E-liquid concoctions usually include a mixture of flavors, aromatic additives and nicotine or THC (the chemical in marijuana that causes psychological effects), dissolved in an oily liquid base.
Michele Hart, clinical pulmonary nurse at Baystate Pulmonary Rehabilitation, points out that vaping coats the lungs not only with steam but also with harmful chemicals. E-cigarette vapor can also adversely affect immune cells in the lung environment and cause lung inflammation, another precursor to cancer. When vaping, a device (usually a vaporizer or a mod, an improved vaporizer that may look like a USB memory stick) heats a liquid (called vaping juice or electronic liquid) until it becomes a vapor that is inhaled. Like the vapor inhaled by the user of the vaporizer, the second-hand vapor created by a device contains the same potentially harmful chemicals.
While second-hand vapor may not affect the lungs in the same way as vaping, it's best to avoid it if possible.