Marijuana Use Up In Adults, Not Teens Since recreational use of marijuana in Washington became legal in 2012, marijuana use increased among adults, but not among teens. Read More Substance Use, HealthLouise CarterOctober 25, 2018cigarette smoking, health, health insurance, King County, lgb, lgbtq, marijuana, substance use, tobacco, disability, infant mortality, adolescent birth, teen birth, LGBTQ community spotlightComment