The Centers for Disease Control and Prevention has finally named a culprit behind the mysterious lung illness tied to vape use that's been making headlines since the summer.

A new report identifies vitamin E acetate as a cause of the illness that has come to be identified as EVALI. The CDC reached that determination after 29 EVALI patients from 10 different states were tested, and the offending substance showed up in every result.

"Vitamin E acetate is used as an additive in the production of e-cigarette, or vaping, products," the report notes. "This is the first time that we have detected a potential chemical of concern in biologic samples from patients with these lung injuries."

While this formal identification of vitamin E acetate as a cause of EVALI represents a positive step, it's not exactly surprising news. The vitamin supplement was identified in early September as a possible cause, after the U.S. Food and Drug Administration found it in cannabis products used by a number of people who had fallen ill.

"While this is the first common element found in samples from across the country, health officials said it is too early to know whether this is causing the injuries," a Washington Post report noted at the time.

The CDC test involved analyzing fluid samples collected from patients' lungs. Out of the 29 patients tested, THC (the psychoactive ingredient in cannabis) was found in 82 percent of the samples and nicotine was found in 62 percent of the samples. This suggests that, at this point, any vape poses a potential danger.

The report reflects that risk. "CDC continues to recommend that people should not use e-cigarette, or vaping, products that contain THC, particularly from informal sources like friends, or family, or in-person or online dealers," it cautions. "We will continue to provide updates as more data become available."

It's worth pointing out that the higher THC risk factor was first suspected and then later identified in October

Research continues, as it's still possible that there's more than one substance behind the EVALI outbreak. The illness has now shown up in every state except Alaska, as well as Washington, D.C. and one U.S. territory. In all, 39 deaths have been reported.

While the CDC continues to recommend staying away from vaping products entirely for the time being, the report acknowledges that some options are riskier than others. Since THC has popped up in most of the samples tested, the agency recommends avoiding any e-cigarettes or other vaping products that contain THC.

Further, the evidence seems to suggest that THC products obtained from "informal sources like friends, or family, or in-person or online dealers" are a source of the illness. So while the blanket recommendation to avoid THC vaping products remains, the CDC strongly advises against purchasing such products "off the street."

If you do insist on using THC vapes and you live in a place where cannabis is legal for medicinal and/or recreational use, you should at least take the step of doing some research. Ask the companies that make these products what kind of additives are used during production.

Really though, your best bet for now is to just follow the CDC's guidance and steer clear of vaping products that contain cannabis.