E-cigarettes, or vaping, has surpassed traditional cigarette use says the Centers for Disease Control, but a new research find that despite manufacturers’ claims, they’re not necessarily a safer alternative.

A study published by a team at the Harvard T.H. Chan School of Public Health found that most flavored e-cigarette and refill liquids contain harmful chemicals that can cause a respiratory disease which scars the lung and makes breathing difficult. The team tested 51 types of flavored e-cigarettes and liquids by leading brands and found that 47 contained diacetyl, acetoin, or 2,3-pentanedione.

“Since most of the health concerns about e-cigarettes have focused on nicotine, there is still much we do not know about e-cigarettes. In addition to containing varying levels of the addictive substance nicotine, they also contain other cancer-causing chemicals, such as formaldehyde, and as our study shows, flavoring chemicals that can cause lung damage,” study co-author David Christiani said.

The CDC also cites that e-cigarette use has tripled between 2013 and 2014 among middle and high schoolers, rising from approximately 660,000 to 2 million students.

Think you’re safe just because you’ve managed to avoid the vaping fad? Not quite. Also containing traces of diacetyl is microwaveable popcorn. Smoker or not, you’re basically bound to lose if you’re one to enjoy artificial foods on a regular basis.

➤ Chemical flavorings found in e-cigarettes linked to lung disease

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