Bringing attention to e-cigarette pH as an important element for research and regulation

Discussion The variation of pH among e-cigarette brands that contain the same amount of nicotine, and even among different flavors within the same brand, is an important finding. Since pH determines the amount of nicotine that is present in the biologically available unprotonated form, e-cigarettes with the same nicotine content, but different pH, may deliver different doses of nicotine to users. [...]potential pH variations represent an important factor that should be taken into account while designing and interpreting research studies involving e-cigarettes.