dried tobacco leaf Harvesting, Curing, and Fermenting 15%–18% Appearance Dried tobacco leaves with cigarette

Smoking-related leukoplakias most commonly involve the undersurface of the tongue and throat area, locations that account for 75% of oral cancer in the U.S

This effect is best understood in the context of gene promoters where DNA methylation can impair physical binding of transcription enhancers and promote the recruitment of methyl-CpG-binding domain proteins that increase chromatin condensation and thus decrease the DNA accessibility for the transcriptional machinery (Portela and Esteller, 2010)

You could take it like that

M., Geng, Y

Experiencing stress due to increasing problems in implementing the educational mission was positively related to smoking cigarettes, and the higher the probability of severe COVID-19 infection was assessed, the more likely teachers were to smoke