https://www.sciencedaily.com/releases/2021/06/210624135526.htm

In contrast to consistent rates of marijuana and alcohol use, nicotine vaping in high school seniors declined during the pandemic, along with declines in perceived availability of vaping devices at this time. The legal purchase age is 21 for nicotine products and alcohol in all states, and for cannabis in states that have legalized nonmedical cannabis use.

"Last year brought dramatic changes to adolescents' lives, as many teens remained home with parents and other family members full time," said NIDA Director Nora D. Volkow, M.D. "It is striking that despite this monumental shift and teens' perceived decreases in availability of marijuana and alcohol, usage rates held steady for these substances. This indicates that teens were able to obtain them despite barriers caused by the pandemic and despite not being of age to legally purchase them."