5 cigarettes a day really bad No Safe Level of Smoking Smoking: Effects, Risks, Diseases, Quitting

95% Approximately 95% of smokers started smoking before they reached the age of 21

Cullen KA, Ambrose BK, Gentzke AS, Apelberg BJ, Jamal A, King BA

However, this easy handling system remains to be characterized in a complete setup dedicated for e-cigarettes aerosol exposure using an appropriate puffing regimen

Ask if they have heard of vaping or if they have seen their friends using e-cigarettes

A transcriptomic analysis between primary oral and bronchial models following e-cigarette aerosol exposure showed that bronchial epithelium was more sensitive than oral tissue but recovered quicker suggesting a tissue-specific response through distinct molecular pathways [23]

New Bern Sun Journal