A team of Harvard scientists has just published a study in the peer-reviewed journal Environmental Health Perspectives showing that candy-flavored e-cigarette liquid contains chemicals that cause the serious lung disease Popcorn Lung.
The study results reveal that 75 percent of the 51 flavored liquids tested contain diacetyl and other harmful compounds, the Harvard Gazette reports.
Fruit flavor diacetyl, alcohol flavor diacetyl, and candy flavor diacetyl are some of the culprit ingredients associated with the serious and irreversible lung disease, bronchiolitis obliterans, commonly known as Popcorn Workers Lung or Popcorn Lung. Popcorn Lung is an obstructive lung disease in which the bronchioles of the lungs are blocked by the growth of fibrous tissue. The name traces to the illness developed by employees at a popcorn factory in Missouri that made artificial butter flavoring for microwave popcorn. The workers inhaled diacetyl from the flavoring on a daily basis and developed respiratory symptoms and other symptoms, according to the National Institute for Occupational Safety and Health (NIOSH).
The symptoms of Popcorn Lung (bronchiolitis obliterans) usually occur gradually and become progressively worse. Symptoms include:
- Coughing (usually without phlegm)
- Shortness of breath on exertion
- Night sweats
- Weight loss
- Difficulty blowing air out fast and no improvement with asthma medication
Diacetyl, the chemical associated with the development of bronchiolitis obliterans, is a component in a number of the flavorings used in e-cigarette liquids. These chemicals include alpha-diketones 2,3-butanedione, 2,3-butanedione, and 2,3-pentanedione, and acetyl propionyl and they may be responsible for flavorings related lung disease.
People who “vape”—the practice of smoking with e-cigarette devices—with flavored e-cigarette liquids regularly inhale diacetyl. E-cigarettes are increasingly popular among teenagers, and although minors cannot buy traditional cigarettes, they can buy e-cigarettes in many states. At the urging of doctors and public health officials, the Food and Drug Administration (FDA) has proposed new regulations that would include a prohibition on the sale of e-cigarettes to minors.
The Harvard researchers tested 51 types of flavored e-cigarettes and liquids for the presence of diacetyl, acetoin, and 2,3-pentanedione, flavoring compounds that the Flavor and Extract Manufacturers Association lists as “high priority,” for respiratory hazard in the workplace, the Harvard Gazette reports. The flavors tested included fruit and candy varieties that appeal to young e-cigarette users.
To test for the dangerous chemicals, the researchers inserted each e-cigarette into a sealed chamber attached to a device that drew air through the e-cigarette for eight seconds at a time with a resting period of 15 or 30 second between each draw. They analyzed the air stream.
Dr. David Christiani, of the Harvard T.H. Chan School of Public Health was one of members of the research team and was co-author of a paper based on the study. Christiani said the e-liquids contained not only the addictive substance nicotine but also cancer-causing chemicals, such as formaldehyde, and flavoring chemicals that can cause lung damage, according to the Harvard Gazette.