Researchers from the Lawrence Berkeley National Laboratory have found that e-cigarettes emit toxic chemicals like acrolein and formaldehyde. Both are eye and lung irritants, and formaldehyde is a known carcinogen. These harmful emissions come from the combination of propylene glycol and glycerin, which are present in almost all e-liquids.
In total, researchers identified significant levels of 31 harmful chemicals, two of which had never previously been found: propylene oxide and glycidol, both of which are classed as probable carcinogens.
“Advocates of e-cigarettes say emissions are much lower than from conventional cigarettes, so you’re better off using e-cigarettes,” said the study author Hugo Destaillats. “I would say, that may be true for certain users—for example, long time smokers that cannot quit—but the problem is, it doesn’t mean that they’re healthy. Regular cigarettes are super unhealthy. E-cigarettes are just unhealthy.”