https://www.mercurynews.com/2019/10/05/inquiry-into-vaping-deaths-shines-bright-light-on-californias-dark-cannabis-underworld/

As health officials search for the missing link between vaping and a mysterious illness, California’s cannabis community is blaming untested products and devices sold to unsuspecting consumers on the state’s sprawling black market.

It’s still unclear what is causing the lung damage that has hospitalized 805 people and killed 18. But most of the cases have been traced back to illicit products, health officials say. In a cluster of 12 cases treated in the Central Valley’s rural Kings County, where cannabis is illegal, every patient vaped using cannabis or cannabis oil devices bought from an illicit “pop up” shop.