The short answer is "no" vape devices are not safe.
Given that vape devices don’t produce tar or carbon monoxide, two of the main toxins found in a tobacco cigarette, they’re likely safer than smoking a regular cigarette—but that doesn’t mean they’re harmless.
Propylene glycol, one of the main ingredients in e-liquid, is a food preservative. We don’t know yet if vaporized propylene glycol or the other chemicals in the cartridges are safe to inhale. They may irritate the lungs and airways over time. We also don’t know if the chemicals added to give flavour are safe. We do know that heating vaping liquids creates other chemicals that may have harmful health effects.
Because chemicals in the cartridges vary, it’s hard to know what vape device users and people nearby are breathing in. There are also risks using vape devices in pregnancy, as we do know that the chemicals affect how a baby’s brain develops. This remains to be true throughout childhood. This means that children and teens are especially at risk when exposed to these products.
A recent study identified that adolescent vape device users were exposed to cancer-causing organic chemicals when vaping.
CDC in the US confirms that vape associated lung injury (EVALI) is related to the vaping of THC products with vitamin E acetate as the thickening agent.
Dr. Andrew Pipe, a cardiovascular specialist at the Ottawa Heart Institute, presented to 1,400 health professionals across Canada in a webinar in January 2020. In his opinion, based on the current evidence, he would discourage vaping of any product. The webinar recording will be available in the near future.