Vitamin E Acetate has been discovered in a majority of the vaping products that have been tested by the CDC as it investigates vaping-related lung diseases, including two deaths in Illinois and Oregon, the Washington Post reports.

FDA investigators found the oil in cannabis products in samples collected from patients who fell ill across the United States.

The FDA analyzed 12 viable nicotine samples and 18 viable THC products, state officials said. Vitamin E acetate was found in 10 of the 18 THC products.

“This was the only thing that seemed to show up in 10 of the 18 cannabis products,” said one state official who took part in the call.