How E-Cigs Could Hurt Your Lungs

Electronic cigarette flavored liquids may contain chemicals linked to bronchiolitis obliterans, also known as 'popcorn lung'


No, your electronic cigarette isn't healthy. There's already reason to believe it could cause a serious lung disease.

Flavored liquids used in e-cigarettes may contain a chemical linked to bronchiolitis obliterans, often referred to as "popcorn lung," a new study found. Inhaling the chemical, diacetyl, was first found to cause the disease in microwave popcorn factory workers.

Bronchiolitis obliterans is marked by the chronic obstruction of tiny airways in the lungs. Symptoms include wheezing, dry cough and trouble breathing.

"Recognition of the hazards associated with inhaling flavoring chemicals started with 'Popcorn Lung' over a decade ago," said lead study author Dr. Joseph Allen, an assistant professor at the Harvard T. H. Chan School of Public Health, in a press release. "However, diacetyl and other related flavoring chemicals are used in many other flavors beyond butter-flavored popcorn, including fruit flavors, alcohol flavors, and, we learned in our study, candy flavored e-cigarettes."

Often touted as a less harmful alternative to traditional cigarettes, e-cigs are battery-powered devices that heat a flavored nicotine solution to produce a vapor the user inhales. Nicotine is the primary addictive chemical in tobacco. US health officials do not currently regulate the product, but the US Food and Drug Administration has made some moves to do so in the near future.

Because e-cigs are a relatively new — and rapidly growing — phenomenon, sturdy research on their health effects is somewhat limited. And a large portion of the research that has been conducted focuses on the nicotine but not the other chemicals the devices might produce, Dr. Allen and colleagues noted.

Among the more than 7,000 flavors of e-cig liquid, Dr. Allen and team selected 51 from leading brands to test in the lab. In addition to testing for diacetyl, these researchers looked for acetoin and 2,3-pentanedione. The latter two chemicals might also pose respiratory health risks, although that hasn't been confirmed.

After analyzing the vapor from the 51 liquids, which included many fruit and candy flavors, Dr. Allen and team found that 47 contained at least one of the potentially harmful chemicals. Thirty-nine flavors contained diacetyl, 46 contained acetoin and 23 contained 2,3-pentanedione.

This study was published Dec. 8 in the journal Environmental Health Perspectives.

The National Institutes of Health funded this research. Dr. Allen and team disclosed no conflicts of interest.