Health officials said Friday that they've found evidence to suggest vitamin E acetate might be a "very strong culprit" in the slew of deadly vaping-related illnesses reported nationwide.
"For the first time, we have detected a potential toxin of concern, vitamin E acetate, from biological samples from patients," Dr. Anne Schuchat, principal deputy director of the Centers for Disease Control and Prevention, told reporters at a news briefing, according to The New York Times.
Vitamin E acetate was found in the fluids of 29 people who fell ill as part of the outbreak, CDC officials said, according to The Washington Post.
"These findings provide direct evidence of vitamin E acetate at the primary site of injury within the lungs," Schuchat said, according to the Post.
Vitamin E is safe as a vitamin pill or to use on the skin, but inhaling oily droplets can be harmful. It has recently been used as a thickener in vaping fluid, particularly in black market vape cartridges.
Federal and state investigators previously said they were investigating whether contaminants in black-market THC vaping cartridges might be behind the pulmonary illnesses. Symptoms of the vaping-related illnesses have included shortness of breath, fatigue, chest pain, diarrhea and vomiting.
Thousands of people across the country -- including the District of Columbia, the U.S. Virgin Islands and every state but Alaska -- have fallen ill in recent months after using e-cigarette or vaping products, according to the CDC. Health officials have confirmed 39 deaths related to the illnesses in 24 states, including Florida, Georgia, Massachusetts, Mississippi, New York, Pennsylvania, Tennessee and Texas.
Officials said patients who died after reporting vaping-related illnesses were between 17 and 75 years old.
Check back for updates to this developing story.