Two chemicals found in two popular vaping flavors could destroy lung function, experts have warned.
The Harvard scientists’ findings have suggested that inhaling the popcorn and caramel flavored e-cigarette liquids could increase a vaper’s risk of respiratory diseases.
The chemicals reportedly stop the cilia in the airways from working properly. The research was published in Scientific Reports.
Cilia are the tiny hairs that line our airways and move in a beating motion to keep the airways clear of mucus and dirt, allowing us to breathe easily.
Poor cilia function has been linked to lung diseases like chronic obstructive pulmonary disease (COPD) and asthma.
The study found that the popcorn flavored e-cigarette liquid is especially harmful, thanks to the chemical diacetyl.
Diacetyle is used as a flavoring agent in things like butter-flavored microwave popcorn and sweets, and although it’s a safe flavoring to eat, it is dangerous to inhale.
It’s been linked to a condition called obliterative bronchiolitis, dubbed “popcorn lung”, because of the high levels of disease found in workers from factories that used the chemical in microwave popcorn.
Because of that risk, manufacturers have sometimes used another chemical — 2,3-pentanedione — instead.
That chemical is used to make various things, including beer. In e-cigarettes, it’s used to make vape taste like caramel.
But scientists have also claimed that 2,3-pentanedione is equally as dangerous as diacetyle.
They exposed normal human bronchial epithelial (NHBE) cells to the chemicals for 24 hours and found that both diacetyl and 2,3-pentanedione were linked with changes in gene expression that could impair both the production and function of cilia.
Even low levels of both chemicals destroyed the cilia — suggesting that the current standards for safe limits are too low for people who work with them.
And there aren’t actually any standards for e-cigarette users, the report’s authors say.
“E-cigarette users are heating and inhaling flavoring chemicals that were never tested for inhalation safety,” Joseph Allen, associate professor of environmental genetics and pathophysiology and co-author of the study said.
“Although some e-cigarette manufacturers are stating that they do not use diacetyl or 2,3-pentandione, it begs an important question — what chemicals, then, are they using for flavoring?
“Further, workers receive warnings about the dangers of inhaling flavoring chemicals. Why aren’t e-cigarette users receiving the same warnings?”