Marijuana is decriminalized or legal in some form in multiple states. But, because it’s illegal on the federal level, states have had to build their own regulatory infrastructure. Without a centralized body to guide them, regulations in one state can look vastly different from those in another. For more on the scope of the issue, Short Wave host Regina G. Barber talks to independent science journalist Teresa Carr and NPR pharmaceuticals correspondent Sydney Lupkin. Read more of Teresa’s reporting on state marijuana testing, and more of Sydney’s reporting on the ways California is trying to make weed safer.Interested in hearing more science behind consumer products? Email us your question at shortwave@npr.org – we may feature it on an upcoming episode!Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave.