A recent uptick in vaping-related lung injuries across Minnesota may signal the return of a health problem officials thought had peaked last summer — people lacing e-cigarettes with a dangerous additive.

On Friday, state Health Department officials reported that a lab analysis of illicit vaping products connected to a recent outbreak of severe lung injury cases found vitamin E acetate had been added to products containing THC, the active ingredient in marijuana.

Vitamin E acetate, often used as a thickening agent in cosmetics, is also added to THC to make it appear more substantial and, according to the Centers for Disease Control and Prevention, it was found in vaping products and in patients' lung fluid.

"It makes it look like there is more THC in the product," said Cori Cole, an epidemiologist with the Health Department's Injury and Violence Prevention section. "What we don't know is if this is from older batches or new."

Minnesota has had 12 lung-injury cases in patients ages 14 to 46 since June 1. All 12 required hospitalization and five needed intensive care, including time on a ventilator.

Two Minnesota patients submitted a total of 11 vaping products for analysis — with names such as Dank, Lion's Breath and KRT. Vitamin E acetate was found in all 11 products, officials said.

"Using THC-containing e-cigarette, or vaping, products, from informal sources like friends, family or dealers is not only illegal but also a serious health risk Minnesotans should avoid," state Health Commissioner Jan Malcolm said in a statement. "It's clear there are unscrupulous people, who, even after all we've learned, are willing to put potentially deadly vitamin E acetate in these products."

According to a statement Friday by the Minnesota Department of Health (MDH): In late July, it sent an alert to health care providers after learning of suspected cases in Minnesota of severe lung injuries associated with vaping. Vaping-associated lung injury patients typically seek care for symptoms similar to severe COVID-19 infection, including cough and shortness of breath.

Testing of those patients, however, found that they were not infected with COVID-19. They also responded to systemic steroid therapy, the treatment for e-cigarette or vaping product use-associated lung injury (EVALI).

The patients acknowledged a history of vaping. Most reported vaping THC. Some reported using nicotine-based products. Symptoms of EVALI include shortness of breath, cough, fever, malaise and gastrointestinal symptoms (nausea, vomiting, abdominal pain or diarrhea). Other symptoms reported included headache, dizziness and chest pain.

A national trend of vaping injuries was first detected last summer. In many of those cases, lab analysis also found vitamin E acetate. The syndrome was labeled EVALI, or e-cigarette or vaping product use-associated lung injury, after it was tracked by CDC officials. More than 2,800 cases have been reported in the U.S., including more than 100 in Minnesota, according to the latest CDC data. Of the 68 EVALI deaths as of last February, three involved people from Minnesota.

But after peaking in September 2019, the number of EVALI cases nationwide dramatically declined.

Officials credited increased public awareness of the risk associated with THC-containing e-cigarettes, the removal of vitamin E acetate from some product and law enforcement actions.

Staff writer Jeremy Olson contributed to this report.

James Walsh • 612-673-7428