What Causes Vaping-Related Lung Disease? Lung Biopsies Point to This

According to the latest research by Mayo Clinic pathologists on patients, lung damage associated with e-cigarettes is likely due to exposure to toxic chemicals rather than fatty substances like mineral oil.
 
This finding is based on lung biopsy samples from 17 patients across the United States and may help investigators narrow down the list of suspects behind the mysterious disease that has sickened 805 people and led to at least 12 deaths.

The study is one of the first to examine the relationship between biopsy samples from a large group of lung-damaged patients and nicotine or THC in e-cigarettes (the psychoactive component in cannabis).

These findings cast doubt on one theory behind the cause of the problem: that e-cigarette lung damage is a rare type of so-called lipoid pneumonia caused by the accumulation of e-liquid in the lungs.

Brandon Larsen, a surgical pathologist at the Mayo Clinic in Scottsdale, Arizona, stated that none of the 17 cases showed signs of lipoid pneumonia, such as the presence of large oil droplets in the lungs. He is an author of the study, which was published on Wednesday in the New England Journal of Medicine.

"The type of damage we see in the lungs is not damage caused by fat accumulation," Larsen said. "It is toxic chemical damage, similar to that caused by toxic smoke or toxic gas." The lung biopsies did not provide clues about the toxic components, but Larsen suspects it could be some contaminant in e-cigarettes.

The Mayo Clinic study also provides new evidence that vaping-related lung damage is not entirely new. The 17 cases included two previously unreported early cases from 2016 or 2017, predating the current outbreak. Bloomberg previously reported at least 15 early cases of e-cigarette lung damage before this year.

"This is not a new phenomenon," Larsen said. Despite the recent surge in cases, "it has been happening at least for the last few years."

Two of the biopsies came from patients at the Mayo Clinic, while the others were from hospitals across the country that sent samples to the Mayo Clinic for further consultation. Consistent with previous findings, 12 of the 17 patients had a history of vaping cannabis or cannabis oil.