(WAND) - The Centers for Disease Control and Prevention said it has made a potential breakthrough in the vaping illness outbreak that has killed at least 39 people.

The potential toxin at the root of the problem... vitamin E acetate, officials announced Friday.

The compound used in supplements, cosmetics and vaping products was detected in all 29 lung tissue samples from patients that health officials tested.

THC, the active ingredient in marijuana, was found in 23 of the 29 samples tested, officials said.

Nicotine was detected in 16 samples, which came from ten different states.

However, officials said there may be more than one cause for the outbreak of the deadly vaping illness.

Vitamin E acetate is not normally dangerous to swallow or apply to the skin. More studies are needed to determine whether there actually is a link between vitamin E acetate and the vaping-related lung illnesses.

“There is a big difference between putting vitamin E acetate on one’s skin or swallowing a vitamin E pill and inhaling vitamin E acetate in an e-liquid,” officials said.

There have been 2,051 probable cases of vaping illness reported to the CDC as of Tuesday. 163 new cases were diagnosed in he past week.

The number of confirmed fatalities linked to the illness sits at 39.

Health officials are calling the disease EVALI, short for e-cigarette, or vaping, product use associated lung injury. Most patients have reported vaping THC, according to the CDC.

Findings suggest products containing THC, particularly those bought off the street or from illicit dealers, are linked to most of the cases, the CDC said.

The CDC is recommending that consumers stop vaping, particularly THC and especially anything bought off the street.