Investigators have discovered a contaminant in vaping products believed to be linked to the recent outbreak of lung disease.

State and federal health officials have identified the same chemical present in certain products linked to vaping illnesses across the U.S. The contaminant is an oil used in marijuana products derived from vitamin E. It was discovered after investigators in New York State asked patients to submit vape products for testing, and the oil was found in 10 of 18 cannabis products.

For anyone unfamiliar, vitamin E is commonly found in foods like almonds, canola oil and olive oil, which also can be present in supplements and skin care products. While not harmful when ingested or applied to the skin, it can be dangerous when inhaled. Symptoms linked to inhaling the oil include coughing, shortness of breath and chest pain.

As of Aug. 27, the U.S. Center for Disease Control and Prevention has confirmed 215 cases across 25 states of pulmonary lung disease possibly linked to vaping.

“We knew from earlier testing by New York that they had found vitamin E acetate, but to have FDA talk about it from their overall testing plan, that was the most remarkable thing that we heard,” an unnamed official said following a phone briefing this week. It was also revealed at least one vape product a patient submitted tested positive for vitamin E acetate.

FDA officials also revealed to New York health officials there was nothing unusual found in nicotine products but the investigation still is ongoing. A number of illnesses have been linked to nicotine products, as well.

Vaping has been associated with a slew of hospitalization cases in the US.