Hawaii health officials said they will “strictly enforce” a law prohibiting medical marijuana dispensaries from selling vape cartridges made with outside ingredients.

The Department of Health warned the dispensaries last week that it is against the law to sell vaping cartridges that contain nicotine, tobacco or any other non-cannabis-derived product, including organic compounds known as terpenes. They may sell cartridges filled with cannabis, cannabis oils or cannabis extracts manufactured by the dispensary.

“With increasing concerns over vaping related lung illnesses and injuries, the DOH requested ingredient lists from all eight medical cannabis dispensary licensees and learned that five were not in compliance,” said DOH spokeswoman Janice Okubo. “DOH is sending written notices which direct non-compliant licensees to immediately stop manufacturing and distributing the non-compliant … cartridges or face penalties including fines and/or suspension or revocation of their licenses.”

The DOH didn’t release the names of the dispensaries not in compliance since investigations are ongoing, but said it will be “ensuring future compliance” with regular examination of ingredients and on-site inspections.

A week ago health officials urged local residents to stop vaping regardless of substance or source as they investigate a second possible case of serious lung illness associated with the growing trend.

Nationwide, more than 1,000 cases of lung illnesses and 29 deaths have been associated with e-cigarettes. The DOH last month confirmed a teenager as the first reported case of vaping- related lung disease in Hawaii.

Kea Keolanui, spokeswoman for Hawaii island dispensary Hawaiian Ethos, said it will not be easy to regulate vaping cartridges sold by medical marijuana dispensaries.

“If a manufacturer is willing to lie about the ingredients of their cartridges, it would be very difficult for the DOH to discover that addition of outside ingredients,” she said. “We have asked the DOH how they intend to enforce the ban beyond simply asking the licensees on their honor, since the enforcement of this ban on third-party ingredients is something we think will be very difficult for DOH to regulate.”

Hawaiian Ethos has never used outside ingredients, and its vape cartridges have “zero additives,” Keolanui said.

Maui Grown Therapies, the first pot shop to open in Hawaii, said the ingredients used in its devices are exclusively derived from cannabis plants grown in its Upcountry production facilities. Cure Oahu said its medical cannabis products are in compliance.

In a text to patients last week, dispensary Big Island Grown said, “In light of the vaping crisis, the Department of Health is moving to ban all plant-derived and cannabis-derived external terpenes. While we do not agree with this decision and stand by our current distillate carts, we must transition.”

It then put all distillate cartridges on sale. Big Island Grown told the Honolulu Star-Advertiser that it will continue to sell distillate oil in syringes that can be consumed orally.

Justin Britt, CEO of Green Aloha on Kauai, said the dispensary was preparing to sell cartridges in November and had planned on using botanical terpenes found in cannabis from a third-party source to reduce costs for patients.

“We are now purchasing $200,000 in additional extraction equipment (to extract our own terpenes from cannabis) and adding an additional step in the manufacturing process,” he said. “This will increase the price for patients, but the benefit of having a 100% cannabis vape pen (lab-tested) far outweighs the health risk of the black market.”

Other dispensaries, including Aloha Green Apothecary and Noa Botanicals, also had sales on cartridges. Both companies did not respond to requests for comment. Pono Life Maui also did not respond.

Pedro Haro, executive director of the Hawaii Educational Association for Licensed Therapeutic Healthcare, or HEALTH, representing the state’s eight dispensary licensees, said while he understands the “abundance of caution” regarding vaping, “it is important to emphasize that there is not a single case of lung illness reported in Hawaii associated with any product purchased from a state- licensed dispensary.”

Nationally, many cases of vaping-related illness involve illicit off-market products that include tetra­- hydrocannabinol, or THC, the psychoactive ingredient in cannabis, though some victims have fallen ill using only nicotine products legally obtained.

There are now a dozen pot shops statewide run by the eight licensees: five on Oahu, one on Kauai, two on Maui and four on Hawaii island. The dispensaries are responsible for cultivation, manufacturing and retail sales from seed to sale. Products must be lab-tested for potency and purity and free of contaminants including pesticides, herbicides, fungicides, heavy metals, bacteria and mold.