CDC Homes In on the Chemical Villain Causing Mysterious Vaping Illnesses

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Hello and happy Friday, readers!

There’s been a rush to figure out what, exactly, is the chemical villain fueling a growing rash of vaping-related lung injuries and illnesses. The Centers for Disease Control (CDC) on Thursday announced that the total case count had climbed to 2,051, as well as 39 confirmed deaths.

We may finally be getting some answers. Potential culprits have included various compounds including vegetable glycerin, propylene glycol, and vitamin E acetate. But the latter was linked to all cases examined by the CDC, the agency announced in an update on Friday.

The CDC tested lung fluid samples from 29 patients across ten states; all of these sample included vitamin E acetate. The vast majority of the collected samples (82%) included the marijuana psychoactive compound THC while 62% contained nicotine (marijuana vaping pods, depending on the source they come from, may contain nicotine).

“This is the first time that we have detected a potential chemical of concern in biologic samples from patients with these lung injuries. These findings provide direct evidence of vitamin E acetate at the primary site of injury within the lungs,” wrote CDC researchers.

The agency also reiterated its warning to avoid THC-containing vaping products, especially if they come from the black market. And, to be clear, this is still a relatively small sample size, so there could well be other chemicals at play in the illness. But this could prove an initial breakthrough in this particular public health mystery.

Read on for the day’s news, and have a wonderful weekend.

Sy Mukherjee
sayak.mukherjee@fortune.com
@the_sy_guy