Let’s talk about “dewshine.” The CDC is pretty sure that two Tennessee teenagers who died earlier this year overdid it on an insane cocktail of Mountain Dew and racing fuel, an even more twisted variation on the soda-and-poison theme laid out by purple drank. Sobriety-hating humans have a long history of cutting toxic substances with better-tasting liquids — in this case, the acid-green ambrosia long peddled by PepsiCo — but no amount of Voltage or Baja Blast can temper the eye-watering and potentially life-ending burn of racing fuel.

Is it too idealistic to dream of a nation where teenagers are smart enough not to ingest anything intended to be pumped into the back end of a car? The case of dewshine forces us to nod our heads in reluctant affirmation. In choosing racing fuel as their intoxicant of choice, young people are showcasing their ignorance of this basic chemistry. Is methanol ethanol? No, no it is not. While the latter can be safely imbibed with temporary, though nauseating, consequences, drinking the former might kill you and will likely blind you.

Nonetheless, racing fuel containing methanol has, according to HotRod.com, “come back in a big way.” For the underage set, it’s probably easier to get than ethanol itself.

To be fair, humans have been getting the two confused for centuries. For those grasping desperately at intoxicants, it’s easy to look at “methyl alcohol” and “ethyl alcohol” — more cumbersome names for methanol and ethanol — and ignore the chemical prefixes. To do so is, to put it lightly, fucking dumb: The terms refer to structural differences between the two chemicals (methanol has one methyl group, while ethanol has two), which dictate the way our body metabolizes them.

Flooding the body with the powerfully citrusy admixture of Mountain Dew and methanol causes the body to undergo metabolic acidosis; that is, the blood gets dangerously acidic. When its ingested, methanol is first metabolized into the chemical formaldehyde — yes, the same substance we bathe corpses and preserve pigs in — and then into formic acid, which is what actually shuts the body party down.

Methyl and ethyl alcohol, also known as methanol and ethanol, have very different effects when imbibed with Mountain Dew.

The increasingly bleary eyesight that results from dewshine bingeing — it just takes 10 milliliters to cause vision loss — is thought to be the result of formic acid causing changes to the eye’s fundus within the rest few hours. Eventually, water pools in the retina and the optic disc, causing a condition known as edema, and hyperemia — an excess of blood — ensues. Unless the formic acid is filtered out of the body through, say, dialysis, blindness could set in after as little as 48 hours.

Drinking as little as 15 milliliters of pure methanol (roughly two U.S. tablespoons worth) enough to kill a person. It’s not immediately noticeable. Sucking it down does, admittedly, get you drunk — like ethanol, it’s a depressant of the central nervous system — but its inebriating effects are generally less intense than those of booze itself, at least at first. But about 10 hours after drinking, a set of secondary symptoms sets in, which include the aforementioned blindness and acidosis. The slow buildup of formic acid in the body eventually causes respiratory failure, which, in most cases, is synonymous with death.

The fatalities earlier this year can’t be good for Pepsi’s throwback to Mountain Dew’s roots, the high-caffeine, crystalline Dew variant known as — yup — Dewshine, which launched last year. While the new Dew product is not alcoholic, Dewshine was, when it originated in the “gnarled backwoods” of Tennessee, essentially moonshine. Whether the methanol-laced cocktail was actually inspired by its historic namesake remains to be seen (or, let’s be real — not).

The beverages in the Mountain Dew family are potent enough in their original forms. Adding racing fuel to the mix is unnecessary adulteration, dangerous and disrespectful. Dewshine, a debased concoction, presents an extreme case, one in which doing the Dew is ill advised.