It’s ham-handed metaphor time!
Imagine a group of alien scientists has arrived at our galaxy and is eager to study our society, with a specific interest in our eating and drinking customs. The concept of warmed drinks is foreign to them, as they find all sensations of heat unpleasant and are typically damaged by things we’d consider to be just-more-than-warm. Stimulant use is similarly harmful to their systems. Hoping to kill two birds with one stone, they decide to study coffee.
Now, the aliens are much further along scientifically than we are; we don’t have interstellar travels or tenticular extenders or any of that cool stuff. As such, they consider us to be somewhere between “ape” and “slightly improved ape” and don’t feel it’s necessary to contact us about their work. They also suspect, given their biases, that coffee is probably a pretty dangerous drink and that we are either too dumb or too addicted to acknowledge it.
Using their scientific know-how they clone a working human, sans consciousness, to work on. They examine our records and find that coffee is the roasted seed of a coffee plant, boiled in water to produce a hot, brown beverage. They replicate some coffee, boil up a gallon of it, then pour the gallon of boiling coffee (they understand from our records it’s better fresh) down the throat of the clone.
Their experiment results show conclusive evidence that coffee causes massive damage to the digestive tract of humans, including heat damage, inflammation and scarring. The massive influx of caffeine stresses the clone’s cardiovascular system and their simulations show that similar amounts of stress over time would cause significant harm.
In their benevolence, the aliens use their omnipotent alien powers to remove all coffee from Earth and to render all coffee-making equipment inoperable. The Earthlings are upset about this, but the aliens disregard their complaints. They are after all essentially drug-addicted apes and as such need guidance, as proven by the fact that they were drinking a beverage the aliens easily proved to be horrifically dangerous.
The above scenario happens on Earth with Earthling-scientists fairly often, and it’s usually for about the same reason - they are scientists, damn it, and they aren’t in the habit of talking to the dumb apes they are forced to live with. This is especially the case when the particular apes concerned do something the scientists hate, as is pretty safe to assume is the case whenever we see a study from the public health/tobacco studies fields.
I think one of the better examples is this 2015 study of formaldehyde production in e-cigarettes. The premise is simple enough:
At low voltage (3.3 V), we did not detect the formation of any formaldehyde-releasing agents (estimated limit of detection, approximately 0.1 μg per 10 puffs). At high voltage (5.0 V), a mean (±SE) of 380±90 μg per sample (10 puffs) of formaldehyde was detected as formaldehyde-releasing agents. Extrapolating from the results at high voltage, an e-cigarette user vaping at a rate of 3 ml per day would inhale 14.4±3.3 mg of formaldehyde per day in formaldehyde-releasing agents. This estimate is conservative because we did not collect all of the aerosolized liquid, nor did we collect any gas-phase formaldehyde. One estimate of the average delivery of formaldehyde from conventional cigarettes is approximately 150 μg per cigarette,3 or 3 mg per pack of 20 cigarettes. Daily exposures of formaldehyde associated with cigarettes, e-cigarettes from the formaldehyde gas phase, and e-cigarettes from aerosol particles containing formaldehyde-releasing agents are shown in Figure 1.
The first warning sign we see that something has gone terribly wrong is that the authors only ever describe their power-source settings in terms of voltage. For context, voltage in the potential of the power source to do work; by itself, it doesn’t tell us anything more about how much power they are supplying to the vaporizer than me telling you how heavy the person on the long side of a lever is. The authors don’t seem to know this, since they don’t supply the resistance of the atomizer (think length of the lever) or the wattage (the number you actually want here, essentially how much lifting power the lever has after all factors are considered).
So immediately we have pretty good evidence that the authors don’t just think of them as superior to us apes, but also that their general knowledge of chemistry makes them fluent enough in all sciences that there was no need for them to consult an engineer on how the devices actually worked.
Some better studies on the same topic, like this, managed to at least list the resistance, but if you sift through the various papers from this time period that follow this general method of running e-cigarettes, you find a pattern: The authors would buy an e-cigarette from somewhere, turn it on at the lowest setting, and find it produced either very low levels of formaldehyde in the “much less than a cigarette” category or none at all, then gradually turn up the power until it produced alarming levels of embalming fluid. And, like magic, they had very concerning levels of toxins of the kind that would let them get published.
I want to stress that this isn’t entirely illegitimate; formaldehyde is bad news of the known-carcinogen variety, and we have a pretty good idea of the risks it gives over time. If all it took to turn the device from a reduced-risk alternative to cigarettes to a cancer-spewing death dragon was a user pushing a couple buttons, then this was a legitimately concerning or even terrifying thing. Without some sort of limiter controlling when the power levels were too high this was a real risk, and the devices themselves didn’t have these kinds of limits built in.
Meanwhile, during the era when this type of study was popular, all the e-cigarette folks who had some actual experience with the devices from an end-user standpoint were screaming. To understand why, you need some context of how an e-cigarette works (I’m very sorry and I’ll keep it as short as possible).
On the most basic level, an e-cigarette is a reservoir of e-liquid, a heating element to boil it off into vapor, and a wick to transfer the e-liquid to the heating coil. When the coil is well supplied with e-liquid by the wick, the overall temperature of any of the components never gets much over the boiling point of the liquid (this is true of any liquid that can be boiled and any heat source, provided the heat is added gradually). Given a good enough wick, you could potentially run unlimited amounts of wattage through the heating element without anything substantial changing except the amount of vapor produced - the vapor carries off all the energy you added just as quick as you can add it, so the temperatures stay constant and relatively low.
What the e-cigarette people knew that the scientists doing the studies didn’t care to learn is that this situation changes very quickly when the wick can’t keep up with the power of the coil. In that case, the coil gets dry; because there isn’t enough liquid to carry off the heat, the temperature of the assembly spikes and any remaining liquid on the wick literally catches on fire. A good way to think about this is in terms of distilling alcohol - you can evaporate it off pretty easily and safely, so long as you don’t increase the heat suddenly, in which case the whole thing explodes and kills some unfortunate rum-runner.
And the e-cigarette people had a name for this. It was called a “dry hit”, and was universally reviled. As you might expect from burning something that was supposed to be vaporized, it was a surprise hit of unpleasant, harsh smoke that users couldn’t help but be aware with and pretty universally tried to avoid. The limiting factor the scientists failed to find in the devices that kept formaldehyde production at bay was, the users claimed, simply that no sane person would use the devices in the study author’s failure-state settings in the first place.
And so you had thousands of e-cigarette users all incredulously saying nonsense-sounding things like “wait, they went to 5v on a CE4?” because to anyone who had any idea of what that device was and what it was a designed to do, it was no surprise that it produced formaldehyde at those settings.
None of this is meant to convince you on the actual matter of e-cigarettes and formaldehyde - in fact, since these articles were published there’s been a whole cottage industry of debunking and rebunking them (pick your poison on which studies to believe - this isn’t exactly a top-tier subfield so there’s some problems with virtually all of them). But if you are a scientist who is looking into the dangers of the actual use of a product, then it’s important that you look into how the product is actually used.
If you care about the people you are ostensibly trying to help, this is pretty easy - you talk to them and find out how they do what they do. But if you have contempt for them, or you’re only concerned with producing something publishable, truth-be-damned, this step gets missed. And so around the fringe of science you find a lot of stuff like this - essentially aliens who never found out humans let coffee cool before they drink it, confused about how they are the first ones to notice the massive tissue damage.
Of course, "dripping" - dropping your homemade vaping mix directly onto heated coils - threw any this splitting hairs out the window. But common sense informed anyone they saw vaping for the first time that that massive cloud exhaled into the air couldn't be a "safer" thing.