Vapor cigarettes, also known as e-cigarettes, do release toxic vapors into the air and worsen air quality, although there is much less second-hand danger than with traditional cigarettes. Tests have shown nicotine, aluminum and other dangerous chemicals in the air around e-cigarette smokers.
Many of the harmful compounds released into the air when traditional cigarettes are smoked come from the combustion process. Burning a cigarette produces polycyclic aromatic hydrocarbons, which are damaging to lungs. Nicotine and some heavy metals, such as lead and zinc, are also found in cigarette smoke.
Vapor cigarettes produce little to no polycyclic aromatic hydrocarbon, but studies have shown that they do still release nicotine into the air when used with cartridges that contain it. They also release heavy metals into the air, which can contribute to toxic build-up in those exposed. Lead and zinc are generally present at much lower rates than in traditional cigarette smoke, but Science Daily reports that researchers found a toxic element called chromium in e-cigarettes but not paper cigarettes. Vapor cigarettes also contain nickel in amounts up to four times higher than those found in paper cigarettes.
Researchers theorize that these toxic metals may be introduced into the vapor as a side effect of the manufacturing process, so there may be potential to reduce them. As of 2015, however, e-cigarettes are safer for bystanders than traditional cigarettes, but still pose health risks.