The vaping illness outbreak is strengthening the argument for legalizing marijuana

At least 33 people have died and nearly 1,500 have fallen ill in the vaping-related lung illness outbreak that’s swept across the country since March. And months into their investigation, disease detectives at the Centers for Disease Control and Prevention say they still don’t know exactly what’s causing the severe shortness of breath and chest pain that’s landed people in hospitals.

One class of vaping product, however, has consistently been implicated in the illnesses: unregulated and unlicensed e-cigarette cartridges that contain THC, the main psychoactive chemical in cannabis.