For something that so many groups seem dead set on banning, electronic cigarettes have had a remarkable growth since their introduction in 2004. It had been projected that “vaping”—the word used to describe the smoking of e-cigarettes— would exceed conventional cigarette smoking in three decades, but their popularity took off so extraordinarily that that particular benchmark was reached in 2014. That's the same year that the popularity of vaping exceeded that of smoking among young people in the U.S. The percentage of e-cigarette use among middle school students grew from 1.1% in 2013 to 3.9% in 2014, surpassing rates of youth cigarette smoking.

So, is vaping any better than smoking?

If by “better” you mean that e-cigs are less likely to give you cancer, sure. But a new study just released in the Journal of Molecular Medicine upholds that electronic cigarettes expose the lungs to toxicity, reduce the effectiveness of the immune system and encourage bacterial activity, potentially making some ailments more lethal.

The study, conducted by the University of California-San Diego, exposed mice to e-cigarette smoke for an hour a day, five days a week, over four weeks. The results showed inflammatory markers in the blood and airways of the test subjects were 10% higher after inhaling the vapors than those in unexposed mice. Worse still, bacteria that had been exposed to the e-smoke were more virulent in mice that were already infected with pneumonia.

When “un-vaped” mice were first exposed to methicillin-resistant Staphylococcus aureus (MRSA), an antibiotic-resistant "superbug," they survived. But 25% of mice that were infected with MRSA after being exposed to e-cigarette cigarette died. The e-cigarettes made the superbug even more superior!

Dr. Laura E. Crotty Alexander, the Director of the university's school of medicine was not surprised, remarking that “We already knew that inhaling heated chemicals, including the e-liquid ingredients nicotine and propylene glycol, couldn't possibly be good for you. This work confirms that inhalation of e-cigarette vapor daily leads to changes in the inflammatory milieu inside the airways."

The researchers have not yet determined exactly which lung and systemic diseases would be caused in e-cigarette vapor inhalation, but they note that acute toxicities will result from the inflammatory changes involved. And taken in high doses, the vapor can directly kill lung cells.

The study examined a number of e-cigarette, and concluded that no one brand was any better or worse than any other.