CDC: Vitamin E acetate, THC implicated in vaping-related lung injury outbreak
Products containing tetrahydrocannabinol, or THC, remain a focus in the investigation into the outbreak of lung injuries associated with use of electronic cigarettes or vaping, but new data from CDC’s Environmental Health Laboratory indicate that the presence of vitamin E acetate may also be a factor.
As of Nov. 5, 2,051 confirmed and probable cases of e-cigarette- or vaping-associated lung injury (EVALI) have been reported to CDC by 49 states, the District of Columbia and the U.S. Virgin Islands. There have also been 39 deaths confirmed in 24 states and the District of Columbia.
Although the precise cause of the outbreak remains elusive, Anne Schuchat, MD, CDC principal deputy director, discussed current laboratory findings pointing to vitamin E acetate as a common factor.
“What we know from the laboratory methods that we put in place to look for potential toxins from e-cigarette or vaping products come from bronchoalveolar lavage, or BAL, fluid samples from patients who suffered these lung injuries,” she said during a Nov. 8 telebriefing.
“These new findings are significant because, for the first time, we have detected a potential toxin of concern — vitamin E acetate — in biologic samples from patients with lung injures associated with the use of e-cigarette or vaping products,” she added. “These findings provide direct evidence of vitamin E acetate at the primary site of injury within the lung, and the samples reflect patients from states across the country.”
Vitamin E acetate as a possible culprit
In a report published on Nov. 8 in MMWR, researchers provided details on BAL samples collected from 29 patients with EVALI that were submitted to CDC from 10 different states from August through the end of October.
Nicotine was found in 16 of 26 samples, THC was found in 23 of 28 samples, and vitamin E acetate was found in all 29 samples tested, including among three patients who reported not using THC-containing products, Schuchat noted.
To date, vitamin E acetate — a known additive used to dilute e-liquid in e-cigarette or vaping products containing THC — has been detected in product samples used by patients with EVALI, including in e-liquid testing completed by the FDA and by some state public health labs, such as the Wadsworth Center in New York state.
Schuchat said CDC tested for a wide range of substances that might be found in e-cigarette or vaping products, such as plant oils, petroleum distillates, medium chain triglycerides or terpenes, which are compounds often found in or added to THC products. However, no other potential toxins have been detected in the testing conducted so far.
Vitamin E acetate can be found in other products, such as supplements and cosmetics, and does not cause harm when swallowed in pill form or when applied topically to the skin. However, non-CDC studies have shown that when inhaled, it may interfere with normal lung function, according to Schuchat.
Importantly, though, these findings do not rule out other possible compounds or ingredients.
“Additional studies are needed to establish a causal link between exposure and EVALI, and there may be more than one cause of the outbreak. Many different substances and products are still under investigation, including those tested in these samples,” Schuchat said during the telebriefing.
Potential risk factors for EVALI
During the Nov. 8 telebriefing, Jennifer Layden, MD, PhD, chief medical officer and state epidemiologist at the Illinois Department of Public Health, discussed additional findings published in MMWR that shed some light on which e-cigarette users may be at greater risk for EVALI among people in Illinois. Using an online public survey developed by the Illinois Department of Public Health, Layden and colleagues gathered baseline data on e-cigarette users, comparing a subset of survey respondents with patients with EVALI to identify potential risk factors for the condition.
Of the 4,631 adult Illinois residents who completed the survey, all of whom reported recent use of e-cigarette or vaping products and did not have EVALI, 94% used nicotine-containing products, 21% used of THC-containing products, and 11% used both nicotine-containing and THC-containing products.
Use of THC-containing products was more common among younger survey respondents aged 18 to 24 years, and THC use decreased with age, according to Layden. Additionally, among younger respondents, men reported more frequent use of both THC- and nicotine-containing products than women.
Compared with survey respondents who reported use of THC-containing products but did not have EVALI, patients with EVALI were twice as likely to report exclusive use of THC-containing products. Also, a higher proportion of patients with EVALI reported use of THC more than five times per day.
Patients with EVALI were also nine times as likely to obtain these products from informal sources — such as from a dealer, off the street or from a friend — and eight times more likely to report use of Dank Vapes than survey respondents.
“Our findings reinforce current recommendations not to use e-cigarette or vaping products that contain THC and not to use any e-cigarette or vaping products obtained from informal sources,” Layden said. “In addition, the specific compound or ingredient causing lung injury is not yet known and CDC continues to recommend that people consider refraining from use of all e-cigarette products while the outbreak investigation continues.”– by Melissa Foster
Disclosures: The authors report no relevant financial disclosures.