With a flood of mysterious lung diseases grabbing global headlines and the U.S. moving to ban flavoured e-cigarettes, the ability to vape is quickly evaporating from some markets.

But will the rush to prohibit the products do more harm than good?

In the U.S., eight people have already died from a lung disease connected to vaping and hundreds more have fallen ill, prompting intervention by the highest levels of government.

India, the world’s second-largest consumer of tobacco behind only China, is in the process of completely banning vaping. With more than 900,000 people dying yearly from tobacco-related illnesses, the country’s health ministry noted it felt compelled to act before it became an epidemic among its youth.

But a rush to ban vaping altogether will likely just push more consumers to the black market where the bigger problems lie, said David Hammond, a public health professor at the University of Waterloo in southwestern Ontario. “I don’t think prohibition would make sense. If you prohibit it, you might increase cases of contaminants because you don’t get chance to apply proper standards to products,” Hammond said.

The billion-dollar question, yet unanswered, is what is making consumers sick. “People suspect a contaminant because we all of a sudden saw a big number of cases,” Hammond said. “Like food illness outbreaks, cases clustered together suggest something with the supply chain.”

The most recent report from the Centers for Disease Control and Prevention (CDC) said that most, but not all, cases of illness in the U.S. involved THC and not nicotine. With researchers turning their focus to the presence of Vitamin E as a potential problem in the process, consumers are just tired of the uncertainty.

“People are frustrated by not having enough information,” Hammond said. “But there is no doubt that THC products are widely implicated, with some products purchased outside of the legal market,” he added.

Until the cause is determined, Hammond recommends only vaping dried cannabis and avoiding products from the black market. “For the most part, risks are reduced through good manufacturing. I expect that to remain true. But there may be a question mark at end of that statement now,” he said.

“Health Canada should also be taking a good look at its product standards to make sure we aren’t just saying ‘good luck’ to companies that are trying to make sure their products are not harmful.”

Hammond anticipates that the popularity of vaping will bounce back once the source of the contaminant is discovered because it is safer than smoking cigarettes and is far more convenient. “Vaporizing is ready when you are. It doesn’t smell, it’s easy to conceal and use unobtrusively and you get the immediate effects of smoking compared to edibles. It checks a lot of boxes,” he said.

“This scare is the big unknown. It all depends on how this is resolved,” Hammond said.