This is one of the biggest arguments for the legalization of all commonly used street drugs. Having them illegal only causes harm by putting them into the hands of the totally unregulated and dangerous black market.

Heroin being the biggest example in that the black market is the reason it keeps getting laced with fentanyl, but also smaller things like the inconsistency in marijuana strains. People are gonna smoke weed and do other drugs, might as well make sure it's as safe and consistent as possible.