ST. PAUL — Minnesota health officials say they've taken an important step in linking a chemical in marijuana vaping products to the growing number of cases of lung-injuries and deaths associated with the devices.

The Minnesota Department of Health Public Health Laboratory on Tuesday, Nov. 26, announced that illicit THC products used by 11 of 12 patients who'd developed lung injuries from the e-cigarettes and vapes tested positive for vitamin E acetate. The chemical is a synthetic version of vitamin E used to thicken or dilute THC vaping liquids.

The other patient in the study vaped several THC products and wasn't able to share each for testing. In all, 52% of the 46 THC products put forth by the patients tested contained the chemical, the lab found.

The Minnesota study is one of the first in the nation to evaluate the presence of the chemical in vaping cartridges and liquids used by patients who've sustained lung damage from vaping.

"The findings further support a potential role for vitamin E acetate in causing lung injury associated with vaping products," State Epidemiologist Dr. Ruth Lynfield told reporters. "It may not be that every single cartridge that people vaped had vitamin E acetate, but if some did, particularly if it had a high concentration of vitamin E acetate, it may have been problematic for them."

And in additional tests of THC vaping liquid and cartridges seized by law enforcement, the lab determined that older cartridges and vaping liquids didn't contain vitamin E acetate. Twenty-five illicit THC products seized by law enforcement were tested. And of those, the 20 seized in 2019 tested positive for the chemical while five samples obtained in 2018 did not. The disparity could suggest those selling the illicit vaping liquids added vitamin E acetate to dilute the products in recent months.

The findings were also shared in a Centers for Disease Control and Prevention special publication Tuesday. And CDC officials said that because the impact of the chemical remains unclear, it shouldn't be added to e-cigarette or vaping products.

The CDC earlier this month reported that it found vitamin E acetate in the fluid samples of 29 people with vaping-related lung injuries. The finding made the chemical a "strong culprit of concern" in e-cigarette and vaping products, CDC officials said. But Vitamin E acetate has not been confirmed to cause lung injuries.

Physicians who worked on the study said more research is needed to establish or rule out the connection to lung injuries.

"We are merely saying there is work to be done," Lynfield said. "We are extremely concerned about vitamin E acetate."

Additional surveys of 58 of the 96 patients that the department determined to have e-cigarette or vaping related lung damage between Aug. 6 and Oct. 31 found that 91% reported using illicit THC vaping liquid or cartridges, according to the state's findings. And among those, 67% said they'd used Dank Vapes.

As of Tuesday, the department has identified 125 confirmed or probable cases of vaping-related lung injuries in the state and three have been confirmed dead. Health officials urged those not currently using vaping products to avoid using them and encouraged those using the devices to quit smoking cigarettes to consider FDA-approved cessation alternatives.