The sharp fall reversed months of explosive growth in vaporizer sales — consumers overall have purchased about 356,000 individual vaporizer products from licensed marijuana stores since sales began last November.

Weekly sales of oil-filled vaporizer cartridges, the second-most-popular category of marijuana product (after cannabis flower), fell from a recent peak of $919,776 for the seven-day period ended Aug. 11 to $689,924 last week.

Revenue from sales of marijuana vaporizers at licensed cannabis stores in Massachusetts has plunged 25 percent amid widespread consumer health concerns about the devices, according to data provided to the Globe by the Cannabis Control Commission.

It also came during a period in which four new recreational pot retailers and two medical marijuana dispensaries opened in the state, suggesting the actual decline in demand is even larger.


Experts said the change, which mirrors data from other states where cannabis is sold legally, is almost certainly because of warnings from state and federal authorities that vaporizers are probably the cause of a mysterious outbreak of lung ailments that has killed seven people and sickened another 530 people in 38 states.

Health officials announced the first vaping-related death on Aug. 23.

In Massachusetts, the Department of Public Health said Thursday that it was investigating 45 suspected cases of vaping-related illness.

Horace Small, a marijuana consumer, community advocate, and member of the state’s Cannabis Advisory Board, said he quit vaping at the urging of friends and family members concerned about the news.

“I just completely stopped,” Small said.

“I had this vaporizer that got me through [a vacation], but I had enough people who love me say, ‘Put the vape down’ — so I did. Folks are scared half to death. All my friends are encouraging each other not to vape and just err on the side of caution until there’s more knowledge on what the hell is going on.”


The exact cause of the illnesses remains a mystery.

Food and Drug Administration officials announced Thursday that they have launched a criminal probe into the supply chain of companies that manufacture nicotine vaporizers.

State and federal officials have said they suspect Vitamin E acetate, an additive found in some illicit marijuana vape cartridges, could be one culprit and urged consumers to avoid such products.

Other patients who became sick, however, were simultaneously (or only) using e-cigarette devices.

And experts have raised concerns about additives in regulated marijuana cartridges, such as propylene glycol.

So far, no cases have been linked to the use of marijuana products sold at licensed stores in Massachusetts. Nonetheless, the data from the commission suggest that lingering uncertainty about the cause of the outbreak is discouraging many consumers from using vaporizers.

Brandon Pollock, chief executive of the marijuana company Theory Wellness, said consumer spending on vape cartridges at his company’s recreational shop in Great Barrington has dropped about 20 percent since news emerged of the health crisis. Overall revenue has remained steady, though, suggesting consumers are simply switching to other methods of consuming cannabis.

Like many other licensed marijuana companies in Massachusetts, Theory Wellness has launched a marketing campaign aimed at convincing customers its vaporizers are safe and contain only pure marijuana concentrate and cannabis-derived terpenes, aromatic compounds that occur naturally in the plant.

Pollock is predicting that vaporizer sales will rebound and continue growing. That’s because the devices are more convenient and less odorous than marijuana flower, he said, and because the health scare will prompt consumers to switch from illicit products to those sold in regulated stores.


“I’m not surprised there’s an initial contraction,” he said. “I actually expect an increase in sales as people really exit the black market. I think people right now are just digesting the news — in the long run, this is good for the regulated cannabis industry.”

While the vaping-related illnesses have only recently made national headlines, many local doctors say the issue has probably been going on for much longer.

Vaping-related symptoms — such as fevers, chest pain, and breathing troubles— could easily have been mistaken by physicians for pneumonia or another common infection.

Also, most doctors only recently began asking patients whether they use vaping devices.

A significant number of experienced marijuana consumers and patients said they had stopped using vaporizers before the news of the health crisis, concerned about the presence of additives or the possibility that the heating coils in cheap, Chinese-made cartridges could be leaking heavy metals into the oil they contain.

“I used vape cartridges as my main source of medicine for about five years, but I’ve actually stopped using those and threw my last one away completely,” said Kate Phillips, a former dispensary manager who uses medical cannabis to treat symptoms of Lyme disease.

“I started to feel health effects I didn’t like, and at the end of the day, the dispensaries just couldn’t back up their claims that these additives and the disposable cartridges are safe. I didn’t feel like being a guinea pig.”


The Cannabis Commission last week voted to require licensed marijuana companies to disclose more information on packaging about the types and quantities of additives in vaporized cartridges.

It will soon send out a bulletin and do a survey about vaping to the companies it regulates and is coordinating with testing labs about whether they can detect possibly harmful additives.

Dan Adams can be reached at daniel.adams@globe.com. Follow him on Twitter @Dan_Adams86. Felicia Gans can be reached at felicia.gans@globe.com. Follow her on Twitter @FeliciaGans.