Hydrogen cyanide has been detected in several black market marijuana vaping products tested in California, according to an NBC News commissioned report.

Of the three purchased from legal dispensaries in California, the CannaSafe testing company found no heavy metals, pesticides or residual solvents like Vitamin E. But 13 out of the other 15 samples from black market THC cartridges were found to contain Vitamin E.

CannaSafe also tested 10 of the unregulated cartridges for pesticides. All 10 tested positive. The products all contained myclobutanil, a fungicide that can transform into hydrogen cyanide when burned.

Read more at www.nbcnews.com