Even as health officials recommend that medical marijuana users avoid vaping products, medical marijuana companies say their products are safe.

State health officials have advised medical marijuana cardholders not to use vaping products — even those purchased at legal marijuana dispensaries — until a nationwide spate of e-cigarette-related hospitalizations and deaths is better understood.

At the same time, the Ohio medical marijuana industry is taking strides to remind consumers that their vaping products are thoroughly scrutinized to ensure their safety.

“There’s not a whole lot of room for interpretation. It’s pretty well spelled out,” Alex Thomas, executive director of the Ohio Medical Marijuana License Holder Coalition, said of the state’s safety testing and tracking rules. “The product is tracked from seed to sale.”

Though some medical marijuana users are being cautious, many said they will continue to use vaping products sold in the state’s dispensaries.

E-cigarettes, or vape pens, work by heating cartridges containing chemicals such as nicotine or THC — the active ingredient in marijuana — until those substances vaporize so users can inhale them into their lungs.

Some of those hospitalized said they had vaped THC, according to Columbus Public Health Commissioner Dr. Mysheika Roberts and Amy Acton, director of the Ohio Department of Health. In some instances, victims were vaping a combination of legally purchased vaping cartridges and cartridges acquired on the street, health officials said.

Little is known about the black market for vaping products, and the extent of their use is unclear. Columbus police said they are unaware of any arrests made in connection with black market vaping products.

>>Read more: State health director urges medical marijuana users to avoid vaping

Yet on Sept. 13, Westerville police found several vaping cartridges filled with THC and hashish in a search of a Liverpool Place home, according to a warrant filed in Franklin County Municipal Court. So far no one has been charged as a result of the search, and a Westerville police spokesperson did not respond to messages seeking comment on the case.

A handful of medical marijuana patients in central Ohio who spoke to The Dispatch said they will continue to vape regardless of news reports on hospitalizations and deaths.

“It comes down to convenience,” said Diane Gin, 61, of Dublin, who uses marijuana to manage chronic pain from a recent surgery. Gin said she can use the pens discreetly in public.

“I carry (my vape pen) in my pocketbook, and if I’m out and I start hurting or get anxious, I whip out my pen and inhale,” she said. How often she uses the vape pen depends on how much pain she’s feeling, Gin said.

Tim Alley owns the Peace Pipes tobacco and smoke shop in Cambridge in Guernsey County, which sells e-cigarettes and vaping cartridges filled with CBD, a cannabis extract that lacks THC but is said to have a calming effect. He said vaping products took a hit recently.

Though Alley said he trusts the safeguards of the third-party wholesaler he buys vape pens and cartridges from, he has mixed feelings about those products.

“I am a bit conflicted because cigarettes kill people every day and they are still legal,” he said.

Nevertheless, Alley said he will still sell vape pens and cartridges until the laws change.

In contrast, Brian Wingfield, co-owner of the Ohio Cannabis Company dispensary in Coshocton, said the business hasn’t seen a decline in vaping purchases, but patients are asking more questions.

>>Read more: Vaping joins cellphones as recurring problem for school districts

“Everybody is asking, ‘Are you adding the extra items into the product?’” Wingfield said. In a handful of cases, substances such as Vitamin E acetate were found in the vaping products of victims who were hospitalized. “We’re telling them that the products that we’re getting are 100% cannabis.”

Acton recommended in September that medical marijuana patients avoid vaping, and the State of Ohio Board of Pharmacy has urged dispensaries to offer refunds for vaping products. Anyone who experiences problems with a product is urged to call the state’s toll-free medical marijuana helpline at 1-833-464-6627. Multiple dispensaries agreed to offer refunds, but none said that customers have requested them. Dispensary officials are quick to point out that they take the safety of their products seriously.

“All Terrasana dispensary locations will follow the direction of the Board,” Terrasana, a medical marijuana company with dispensaries in Columbus, Cleveland, Fremont and Springfield, said in a prepared statement. “Patients are welcome to stop into one of our four locations should you have any questions or concerns regarding your vape cartridges.”

Industry officials attributed the spate of hospitalizations and deaths to black market vaping cartridges.

“If nothing else, this episode has illustrated why we have a regulated program in the state and why there is a need for smart regulations and testing requirements for these products,” Thomas said. “If you’re a patient or consumer who wants to have peace of mind and certainty, the only place you can buy those products is in a licensed dispensary.”

>>Read more: State investigating reports of 6 Ohioans with severe pulmonary illnesses from vaping

Advocates worry that high prices for vape pens and cartridges at dispensaries are driving patients to buy them on the street. A single day supply of marijuana flower, which is what many users vape, costs between $30 and $50.

“I trust Ohio’s program, because we put the testers in there to protect patients,” said Bob Bridges, who was, until recently, the patient advocate on Ohio’s Medical Marijuana Advisory Committee. But he expressed concern that patients would resort to illegal products if they can’t afford legal ones.

Despite its ubiquity, vaping is still not well understood. When Peter Tandler, an associate professor of chemistry at Walsh University in Canton, started working with two students to research the impact of vaping on the human body earlier this year, he found few existing studies.

“We’re letting people do this and there’s a lot of questions out there that haven’t been answered,” Tandler said. “It’s surprising how little information is out there about the composition of the vaping products going into your lungs.”

Tandler and Dr. Peter Shields, deputy director of Ohio State University’s Comprehensive Cancer Center, hope their work will shed some light on vaping safety.

Shields is overseeing his own study on the impact of vaping nicotine and THC on the lungs of users. His research involves users of legal and illegal THC vaping products, he said.

“We need to figure that out so we can inform the public,” he said.

pcooley@dispatch.com

@PatrickACooley