Despite previous reports, sales of marijuana vape products are plummeting in the wake of a recent outbreak of an acute lung disease caused by vaping. And although the actual cause of this sudden illness remains a mystery, cannabis labs are now testing legal recreational vape products for an additive that experts believe could be responsible for this nationwide health scare.

As of last week, the Centers for Disease Control (CDC) reported 380 confirmed and probable cases of vaping-related lung illness across 36 states. Last Monday, California officials reported the seventh death connected to this illness, the first to occur in the Golden State. CDC officials have advised all Americans to avoid using all vape products until they have determined the cause of the illness, which can cause shortness of breath, coughing, fever, nausea, and chest pain.

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Although early reports have connected this illness with black market vape cartridges, concerned customers have also been steering clear of legal vape products. On the week of August 19th, when only a few cases of the illness were reported, weed vape sales accounted for 32.8 percent of California's adult-use retail market. As of last week, the share of vape sales plunged to 29 percent — a 12 percent drop in market share.

Colorado saw an even steeper drop of 24 percent of market share, from 19.2 percent during the week of August 19th to 14.5 percent by the week of September 9th. Nevada reported a modest drop from 22.4 percent to 19 percent, and Washington's vape sales share fell from 17.3 percent to 14.6 percent over the last three weeks. But, fortunately for vape manufacturers, sales are up significantly over this time last year, despite the recent decreases.

Pepe Breton, owner of Euflora cannabis shop in Denver, said that only two or three out of every hundred customers seem concerned about vape products. “We’ve had a few people that said they were going to stay away from vaporizers for the moment and they were going back to flower,” Breton told Marijuana Business Daily. 

“We are getting a lot of questions about the issues that are happening nationwide,” said Jerina Pillert, co-owner of Hashtag Cannabis in Washington. “We’ve been telling our customers that we share their concerns and we have testing results for each product we carry at both stores if they ever want to see it.”

Experts currently believe that vitamin E acetate, an additive commonly added to flavored black market vape cartridges, may be responsible for this illness. In response to this information, cannabis testing labs in many adult-use states have started explicitly testing vape products for this additive. Labs in Washington, Pennsylvania, California, and Colorado have all announced that they are working to develop tests for vitamin E acetate, and many have agreed to conduct these tests free of charge.

“It’s not that hard of a test to run, and it’s not that expensive,” said Edward Sawicki, CEO of California-based Think20 Labs, to Marijuana Business Daily. “We’ll probably eat the cost because we want to make sure the product is safe.” 

Keystone State Testing, which tests medical marijuana products in Pennsylvania and North Dakota, also said that they will be conducting tests, even though Pennsylvania already bans vitamin E additives in legal weed products.

Kelly Greenberg, Keystone's owner and chief science officer, noted that other states might have more problems with additive contamination “because there are no real standards and no oversight.” The cannabis industry has already condemned the federal prohibition of cannabis for allowing this illness to spread, as a lack of consistent, nationwide regulations creates space for untested and unregulated weed products to proliferate, especially in states where pot is still illegal.