An article published in The New England Journal of Medicine from a team of Mayo Clinic researchers is raising doubts over the previously floated hypothesis that "lipid pneumonia" is responsible for the current vaping crisis. Based on reviews of lung tissue biopsies the new research claims there is no evidence of oil accumulation but instead identifies direct tissue damage most likely caused by toxic chemical fumes.

As of late September, the Centers for Disease Control and Prevention (CDC) reported 805 confirmed and probable cases of lung injury associated with e-cigarette use or vaping. Twelve deaths are confirmed as being related to the condition with several more under investigation, and the cases now span 46 American states.

Several weeks ago a University of Utah team presented a strong hypothesis suggesting the mystery illness to be a new form of lipoid pneumonia. This was based on close investigation of several local cases revealing lipid-laden macrophages in the lungs of all studied patients. The hypothesis was that certain vaporized oils enter patients’ lungs triggering the acute condition.

The new Mayo Clinic research counters this hypothesis. After studying lung biopsies from 17 patients the researchers found no trace of lipid accumulation.

"While we can't discount the potential role of lipids, we have not seen anything to suggest this is a problem caused by lipid accumulation in the lungs,” says Brandon Larsen, a surgical pathologist from the Mayo Clinic. “Instead, it seems to be some kind of direct chemical injury, similar to what one might see with exposures to toxic chemical fumes, poisonous gases and toxic agents.”

No single product or liquid unified all 17 studied patients, although 71 percent were noted as vaping marijuana or THC oil. The new research suggests the lung illness seems to be caused by direct tissue damage from chemical contaminants or other noxious agents within vape liquids.

"We were not surprised by what we found, regarding toxicity," says Larsen. "We have seen a handful of cases, scattered individual cases, over the past two years where we've observed the same thing, and now we are seeing a sudden spike in cases.”

A recent statement from the CDC offers a reminder that there still seems to be no singular cause or corresponding factor linking all the identified cases outside of straightforward e-cigarette use. An analysis of 514 patients by the CDC found 77 percent used THC-containing products, while 16 percent exclusively used nicotine products.

The new research was published in The New England Journal of Medicine.

Source: Mayo Clinic