A small study of lung biopsy specimens clearly demonstrates the damage of vaping to the lungs, particularly vaping tetrahydrocannabinol (THC), pathologists concluded in a recent article in the American Journal of Clinical Pathology.
Vaping typically refers to the inhalation of aerosol with heated nicotine, flavorings, or marijuana from electronic cigarette (e-cigarette) devices. The inhalation of aerosol with superheated THC or similar plant substances at high concentrations is known as "dabbing."
The researchers examined lung biopsy tissue from eight men between the ages of 19 and 61 who had respiratory symptoms and had engaged in vaping or dabbing within the past 90 days, with no other plausible diagnosis. The study results were reported by Dr. Sanjay Mukhopadhyay, director of pulmonary pathology at the Cleveland Clinic, and colleagues on October 17 in the journal.
Of the eight patients included in the study, all had been vaping THC and two were also vaping nicotine. One patient had engaged in dabbing.
"Lung biopsies (seven transbronchial, one surgical) showed acute lung injury, including organizing pneumonia and/or diffuse alveolar damage," the authors wrote.
In a statement from the Cleveland Clinic, they noted that the evidence to date on vaping injury has been limited -- in fact, this is only the second study to include an analysis of lung tissue in people with respiratory symptoms, according to the researchers.
Consistent with reports in the literature, the fact that all patients were vaping THC means that "THC or a component in THC-containing vape fluid may be implicated in vaping-associated pulmonary illness," Mukhopadhyay and colleagues wrote.
According to the U.S. Centers for Disease Control and Prevention, as of October 8, there were 1,299 confirmed and probable cases of lung injury associated with the use of e-cigarette or vaping products. Among those for whom information was available, 32% reported exclusive use of THC products and 13% reported exclusive use of nicotine-containing products.