As marijuana sales increase across the board, vaping weed from an e-cigarette-style device is also becoming more popular.
Vaping weed is relatively odorless and discreet, compared to smoking dried marijuana flower. And in the same way consumers are replacing conventional tobacco with e-cigarettes, Aaron Smith, CEO of the National Cannabis Industry Association, says vaping is increasingly the preferred method of consumption. "We're definitely seeing an increase in sales for vapes," he says.
But what, exactly, is in liquid versions of pot that are vaporized and inhaled? And how does their safety compare to conventional smoked marijuana? There, much is unknown.
Smith, as well as some researchers, posit that vaping pot — similar to vaping nicotine — is potentially easier on the lungs than smoking, because the liquid inside is heated to lower temperatures that may do less harm.
Sparse data
On the other hand, research on the health effects of marijuana is sparse because it remains federally illegal. Plus, no two vape brands are alike; there is a huge variety of products available on shelves today in the states where marijuana is legal. These vapes contain many other chemicals besides the drug itself that make each product different. And often, it's those other chemicals that prove problematic: In 2019, for example, 68 people died and thousands of others fell ill with mysterious lung damage eventually traced to e-cigarettes laced with pot and an additive called vitamin E acetate.
Smith says that's where legalization and regulation are helpful in providing some oversight of the ingredients. He says each state regulates and tests what goes into vaped products, "to ensure that these products are tested, dangerous chemicals are not used and in the process," he says.
But safety testing of vaped products show many chemicals are evading those regulations, says Josh Swider, CEO of Infinite Chemical Analysis Labs, a company that chemically evaluates marijuana products in all their forms.
Concentrated THC, concentrated chemicals
He says some states that allow marijuana to be sold also screen for up to 66 pesticides, yet there are thousands of other unauthorized chemicals that growers or processors use that he's identified throughout the country's pot supply.
He says distilling THC, the psychoactive ingredient in weed, is also a problem. "When you concentrate your flower cannabis into a concentrate, most pesticides come over and concentrate during that same procedure."
Those dangers are not limited to the drugs extracted from marijuana plants, because synthetically manufactured THC goes through a chemical process that leaves behind dangerous residues. Swider says about a quarter of those contain a corrosive, toxic chemical similar to sulfuric acid.
Swider, who supports access to safe marijuana without such adulterants, says the best way consumers can protect themselves is by seeking out brands that pledge to use processes that rigorously limit pesticides, and test their own products to ensure they are not contaminated.
Teens are vulnerable and at risk
Contamination is not the only danger vaping weed poses, says Dr. Deepak Cyril D'Souza, a psychiatry professor at Yale who's researched the effects of THC on mice for three decades. He says the potency of THC in the average vape pen is also a major problem.
"The story about concentrates is that the amount of THC that's present in these concentrates is far in excess of what average weed contains," D'Souza says. Whereas the average cannabis flower contains about 17% or 18% THC, the concentration in vapes can reach 95% or higher. And that, D'Souza says, has other implications for public health, especially among teenagers and young adults, who are at greater risk of both addiction and marijuana-induced psychosis.
"The young brain is much more vulnerable to addiction; concentrates are more likely to get people addicted to it," he says. And as marijuana goes more mainstream, he says, that's a message that's often drowned out.
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