Nov. 14 (UPI) -- Three more vaping-related deaths were reported Thursday, bringing the total to 42. In addition, 2,172 lung injury cases have been confirmed in 49 states, the U.S. Virgin Islands, Puerto Rico and Washington, D.C., the government said.
Meanwhile, U.S. Senate members have criticized the Food and Drug Administration for taking so long to start regulating vaping products. The Senate's Committee on Health, Education, Labor & Pensions grilled representatives of the FDA and Centers for Disease Control and Prevention on Wednesday.
President Donald Trump and top U.S. health officials met two months ago to work on a vaping policy, but nothing has yet emerged from the FDA. Last week, Trump said he wanted to protect jobs, and that vaping had become a "pretty big industry."
Also this week, a Detroit hospital announced that a Michigan teen with the vaping illness underwent a double lung transplant in October and was recovering well.
The likely cause of many of the confirmed cases remained a mystery until last week, when the CDC announced it had pinpointed vitamin E acetate as a "chemical of concern" in lung fluid. It was found in samples collected from 29 patients in 10 states who suffered lung injuries, two of whom died.
Vitamin E acetate, a common substance approved for foods and cosmetics, causes an immune reaction similar to pneumonia in the lungs when vaporized and inhaled.
"These findings provide direct evidence of vitamin E acetate at the primary site of injury within the lungs," the agency said last week.
Investigators for the U.S. Food and Drug Administration and CDC have said that vitamin E acetate was found in THC vape cartridges patients said they purchased through informal sources, such as online, through friends or off the street.
The diluent agent has been used as a cutting agent for THC vaping cartridges. It was sold online under different names such as "Honey Cut" and "Uber Thick."
Makers of illegal THC cartridges increased their profits by adding vitamin E acetate and reducing the amount of THC oil used in vape cartridges, said Anne Schuchat, the CDC's principal deputy director.
However, the agencies have said other toxic chemicals or a combination of substances might be contributing to the vaping lung disease epidemic.
One study by the Mayo Clinic released in October in the New England Journal of Medicine found evidence of "exposures to toxic chemical fumes, poisonous gases and toxic agents," but not vitamin E acetate oil.
Until more information is found, both agencies recommended people avoid vaping THC and nicotine until more is learned about their possible health effects.