E-cigarettes seemed to sweep in a few years ago with the promise of a safe, smokeless alternative to real cigarettes. You didn’t inhale the smoke, so all those cancer causing toxins never made it to your lungs. Even better, switching flavors just meant switching which liquid you used instead of having to buy a whole new pack of smokes. Vaping was to become the new, safe way to maintain a now harmless nicotine addiction.

Except things haven’t turned out so rosy.

First, there is the lesser issue of e-cigarette hardware itself. Hooking up a high-capacity battery to to a heating element that is used to warm potentially flammable liquids has, unsurprisingly, caused accidents. The battery inside an e-cig is more or less the same as the ones that power our smartphones. Modern batteries store a lot of energy in a small space, and if anything goes wrong that energy gets released as an uncontrolled jet of flames and burning plastics instead of a nice steady flow of electrons. Just ask Samsung, who had to recall every single one of their Galaxy Note 7 phones a few years back. Or talk to the makers of battery-powered self-balancing “hoverboards” whose quality control was so bad across the board that they were outright banned in the UK because their batteries were such a fire risk.

Two notable reports of e-cig fires include a young man who was caught on store video as his pocket burst into flames, and a lawyer who had to rush out of a courtroom when one of the spare batteries he had in his pocket began smoldering.

E-cigs aren’t exploding left, right, and center, but poorly made or poorly maintained e-cigarettes certainly can become a fire risk.

The second, more notable issue of e-cigarettes is the notion that they separate the act of smoking from the harmful chemicals that come with normal cigarettes seems to be incorrect. Vaping has now been linked to several hundred cases of sicknesses and severe lung injuries spread across the nation. E-cigarettes may not have the outrageous amount of harmful chemicals that a traditional cigarette has, but the smoke inhaled from vaping can apparently still be very dangerous. Some doctors are even going so far to say that the damage done by smoking an e-cigarette reminds them of the effects of actual chemical weapons such as mustard gas!

The issues seems to be one of chemical choice and quality control at vaping companies such as Juul. This year, that company was all but forced to remove several of its vaping flavors from stores across the US. Juul is also now tangled up in a whistleblower lawsuit brought against it by one of its former vice presidents of global finance. Siddharth Breja, the vp in question, is claiming that the vaping company ignored the expiration dates of its own products and cut corners to keep up with demand after it was forced to stop selling some of its products.

Any way you look at it, the promise of a safe, non-toxic, high-tech future of smoking delivered by e-cigarettes seems to be going up in smoke.