How many tests have been conducted on cake mixes for their "long-term" health impact? None. You throw a bunch of ingredients together that everyone considers safe and you blast it through enough heat to bake a small chicken or to kill any reasonably-sized living thing, and then you eat it. The texture, flavor, smell, density, and mouth-feel of the resulting cake all depend on the complex chemical reactions of the ingredients -- eggs, flour, sodium bicarbonate, salt, sugar, animal and vegetable oils, chocolate, artificial flavorings, artificial colorings, preservatives, gums & gels.
How about flavored vitamin water?
What's the long-term impact of Slurpees?
How many tests have been conducts on people who have consumed non-dairy creamer for decades?
What about those "apple pie" things they sell at McDonalds?
How many tests have been performed measuring the long-term impact of the textured vegetable protein (TVP) consumed by so many vegans and vegetarians?
Look, I'm not knocking any of these things. I'm just saying that all of this focus on coming up with a 100% certified long-term proof of safety for vaping is a crock, plain and simple; we must lose no opportunity to say so.
Vaping ingredients have been used in foods, beverages, cosmetics, and pharmaceutical products for decades. Millions of people have been vaping them for years, and the best thing that the news can come up with is a story about an idiot with a poorly designed, homemade battery that exploded.
When people complain that, "We don't know the long term health impact," they're either (a) falling prey to the pseudo-scientific belief that there's some measure of safety for everything that we do, or (b) they're trying to fuel paranoia among vapers and anti-vapers.
Look, there may be legitimate health questions about vaping, but "we don't know the long term health impact" answers a question that isn't even worth answering. Reject the basic assumption of the question and get on with things.