E-cigarette vapor contains nicotine, not other toxins

Quoted from the article
"The researchers measured nicotine levels of 2.5 micrograms per cubic meter of air in the first study. Nicotine levels from e-cigarettes in the second study were slightly higher at about 3.3 micrograms per cubic meter. But tobacco cigarette smoking resulted in nicotine levels ten times higher at almost 32 micrograms per cubic meter."