Vitamin E acetate is now a focus of the investigation into vaping-related respiratory illnesses that have sickened 34 people in New York, state health officials say.

As of Thursday afternoon, there have been 361 confirmed or suspected cases reported by state health departments nationwide. Two people — one in Illinois and another in Oregon — have died.

An announcement is expected from the FDA on Friday about its investigation into the illnesses. The FDA wouldn’t confirm to NBC News whether the investigation is focused on vitamin E acetate.

On Thursday, the New York State Department of Health said lab tests showed extremely high levels of vitamin E acetate in nearly all of the analyzed samples of products that contained cannabis.

Vitamin E acetate was not found in the nicotine products tested.

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The compound is a commonly available nutritional supplement that is not known to be harmful when taken as a vitamin or applied to skin, according to the New York State Department of Health.

“We urge the public to be vigilant about any vaping products that they or any family members may be using and to immediately contact their health care provider if they develop any unusual symptoms,” New York health commissioner Dr. Howard Zucker wrote in a new release.

“Vaping of unknown substances is dangerous, and we continue to explore all options to combat this public health issue.”

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