Cannabis Vaping: What’s Safe and What’s Not


PHOTO: Jason Schwartzman and Jenny Slate vape in HBO’s “Bored to Death” (2011)

Download CAL NORML’S Health Advisory on Cannabis Vape Oils

UPDATE 11/14 – A fourth death has been reported in California tied to vaping, this one apparently related to e-cigarettes. CDPH continues to urge everyone to refrain from vaping and e-cigarette use, no matter the substance or source, until the cause of vaping-associated lung disease is known.

UPDATE 10/29: CDPH’S weekly report says the VAPI case count in CA has increased to 144 but no new deaths are reported and the rate of hospital admissions has slowed. 

UPDATE 10/17: The California Department of Public Health reports there have now been three deaths reported in California related to the vape crisis, and one person who became ill from vaping reported buying vapes in two different licensed cannabis retailers. This is the first report of an illness possibly linked to a licensed product in California. Dr. Dean said more investigation was pending. 

A new report from CDPH says 113 people have contracted illnesses possibly related to unsafe vaping: 78 are “confirmed,” 55 are “probable” and 14 are “under investigation.” Over one-third of patients reported vaping multiple products with different active ingredients (THC, CBD, or nicotine) in the last three months: 81% said they vaped a product containing THC; 38% said they vaped CBD; and 47% said they vaped nicotine. Only 10% (8 people) said they vaped only nicotine.  Many patients are surrendering their vape products and those are being tested in an attempt to pin down the culprit(s) as part of a nationwide effort lead by the CDC and FDA. 

UPDATE 10/11: A new study by a Colorado lab points to a new potential culprit in the nationwide wave of lung injuries caused by vaping: a rare disease caused by inhalation of a chemical present in many cheap vape pens that is used to fuse metals together.

UPDATE 10/2: Cal NORML has received a response from CDPH, saying, “All cannabis products, including vape cartridges, must include a list of ingredients on their label. All ingredients and sub-ingredients must be listed. This allows the consumer to make an informed choice about what they are purchasing. This requirement is listed in section 40408 of the regulations, which are posted on our website.  We will continue review our list of allowed/prohibited ingredients (§40300-40306) as more information becomes available through the investigation to ensure that strong public health protections are in place.”

The New England Journal of Medicine published a communication from several doctors who reviewed lung biopsies from 17 patients, all of whom had a history of vaping (71% with marijuana or cannabis oils) and were clinically suspected to have vaping-associated lung injury. The researchers stated, “Much recent attention has been given to the possibility that vaping-associated lung injury may represent exogenous lipoid pneumonia. However, none of our cases showed histologic evidence of exogenous lipoid pneumonia and no radiologic evidence thereof has been found….The significance of this observation remains unclear, particularly in patients with a known vaping history; until more data accumulate, our observations suggest that this finding should be interpreted with caution, as it may simply be a marker of exposure and not necessarily a marker of toxicity…the agents responsible remain unknown.” 

UPDATE 9/30: NBC News commissioned one of the nation’s leading cannabis testing facilities to test a sampling of THC cartridges — 18 in all — obtained from legal dispensaries and unlicensed dealers.

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.

September 19, 2019 – At latest report, at least two Californians have died and dozens more have been hospitalized after using contaminated e-cigs and vape cartridges. To date, all of the casualties in California involving cannabis have come from unlicensed products on the underground market.

Outbreaks of vaping disease have been reported in areas of the state with a high proliferation of unlicensed cannabis distributors, including Los Angeles, Tulare, Kings, and Stanislaus counties, as well as in other states with no legal cannabis at all.

Suspect brands that have been linked to vaping-related disease include: West Coast Carts, Dank Vapes, Lucky Charms, and Green Machine vape pods.

Cal NORML strongly advises consumers to discard all cannabis vape pens and extracts except those obtained from known, reputable manufacturers at state-licensed dispensaries. (If in doubt, you can ask to see their license. To find or verify licensed dispensaries or delivery services, visit Cal NORML’s cannabis resource directory or the Bureau of Cannabis Control.) BEWARE: Many products of suspect origin are being sold in professional-looking packaging. Such bogus products are distributed only on the underground market, not in licensed dispensaries.

Symptoms of vaping-related illness include shortness of breath, coughing, chest pain, nausea, fever, vomiting, or diarrhea. If you are experiencing these, you should call your doctor or go to the hospital.

Cal NORML continues to recommend cannabis vaporization over smoking for users wishing to reduce their exposure to harmful toxins in smoke. Scientific studies have shown that cannabis vaporizers eliminate 95% – 100% of the noxious toxins and carcinogens in cannabis smoke (assuming they don’t use contaminated extracts). Vaporizers also effectively suppress second-hand smoke and eliminate mischievous sparks, embers and ashes. Read more about cannabis vaporization. 

Certain vape products can be regarded as safe:

• Herbal vaporizers that vaporize natural cannabis flowers or leaf by heating it instead of burning it don’t contain toxic additives and are definitely safer than smoking.

• E-cig cartridges that use pure cannabis extracts (including naturally occurring cannabinoids and terpenes) without any chemical additives are likewise safe. Although e-cigs operate at a higher temperature than herbal vaporizers, they still produce fewer toxins than smoked leaf.

Most cannabis vape extracts from good manufacturers contain no additives. Licensed manufacturers are required to list all ingredients on their product labels.  (§40408; 40300-40306). However, flavors must only be listed if they are allergens. There is some concern that flavors are an issue, both in tobacco and THC/CBD oils.

Some manufacturers add chemical diluents or excipients to extracts in order to facilitate vaporization. The most popular of these are propylene glycol (PPG) and polyethylene glycol (PEG). Although some questions have been raised about these additives, they have been widely used in cannabis and nicotine e-cigs for many years without any evident problems.

Other, new, toxic additives are thought to be responsible, at least in part, for the current vaping disease epidemic. In particular, Vitamin E acetate has been detected in some suspect vape extracts. Some labs have announced they can test for Vitamin E, but other unknown additives may also be causing problems. Synthetic marijuana substitutes that are toxic have been found in some purported CBD products. State-licensed CBD products should not have this problem.

In general, state-licensed vape extracts that were already on the market before April 2019, when the first cases of vaping disease were reported, can be assumed to be safe provided they haven’t updated their ingredients. However, it’s possible an additive ingredient has been contaminated.

Studies, federal repeal required. 

Further vaporization studies are needed to determine the safety of vaporized non-cannabis additives, excipients, and flavorings. Cal NORML strongly advocates the repeal of federal laws and DEA regulations that currently prohibit research with cannabis e-cigs.

Also see: Cal NORML Health Advisory: Don’t Use Unlicensed Vape Oils 9/5/2019

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