Doctors are learning more about vaping-related lung illnesses every day.
The latest study confirms vaping does, in fact, injure the lungs.
Dr. Sanjay Mukhopadhyay, director of pulmonary pathology at Cleveland Clinic, led the research and said the study adds to mounting evidence that vaping is harmful to the lungs.
"We have absolute proof that lung damage can occur in some patients who vape, especially those who vape THC; there's absolute confirmation of that," he said.
Researchers studied lung tissue samples from eight men who were hospitalized with breathing problems after vaping products containing THC, a chemical found in marijuana.
They looked at the samples for signs of infection and injury.
Results showed varying degrees of injury to the lung tissue, but no sign of infection.
The team also looked for characteristics of oil damage because of a theory that vitamin E oil in some vape products may be to blame for the illnesses.
However, researchers could not find any signs of traditional oil damage in the tissue samples.
This is just the second study in the world to look at actual lung tissue from people with vaping-related illness -- and both studies show similar results, confirming that vaping can lead to lung injury.
"For the general public, they should be extremely cautious when vaping, especially when vaping stuff that comes off the black market or in an illicit way," Mukhopadhyay said. "There's much more debate to be had, and many more questions to be answered, but there's no doubt, at this point, that some patients get severe lung damage because of vaping."
Now that doctors have confirmed vaping causes lung injury, additional research is needed to determine exactly what chemical contained in vape products is causing harm.
Complete results can be found in the American Journal of Clinical Pathology.