What's Actually In Your Vape Juice — From Someone Who Sold It For 10 Years

I sold vape juice for 10 years. I've been to the manufacturing facilities. I've read the safety data sheets that never make it onto product labels. And I'm going to tell you exactly what you're inhaling.

This isn't meant to scare you — it's meant to inform you. Because the vape industry counts on you not knowing this stuff.

The Base: PG and VG

Every vape juice starts with two primary ingredients: propylene glycol (PG) and vegetable glycerin (VG). On paper, both are "generally recognized as safe" by the FDA — for ingestion. Eating something and superheating it into an aerosol that enters your lungs are two very different things.

When PG and VG are heated to the temperatures vape coils reach (200-300°C), they break down into compounds including formaldehyde, acetaldehyde, and acrolein — all known respiratory toxins.

Nicotine: Engineered for Maximum Addiction

Modern vapes use nicotine salt formulations (often called "nic salts") instead of the freebase nicotine used in traditional cigarettes and older vapes. This was a game-changer for the industry — and not in a good way.

Nic salts are smoother at high concentrations, which means devices can deliver 50mg/mL nicotine without the harsh throat hit that would make freebase nicotine unpleasant. For comparison, a typical cigarette delivers about 1-2mg of nicotine.

The result: faster absorption, tighter addiction loops, and a much harder product to quit.

The Flavoring Problem

Here's something most people don't realize: the flavorings in vape juice are the least regulated and most concerning ingredient category.

Most flavorings used in vapes were originally developed for the food industry. They're safe to eat. But inhaling them? That's an entirely different toxicological profile that, for most flavoring compounds, simply hasn't been studied.

Diacetyl — the buttery flavoring compound linked to "popcorn lung" — was the most famous example. But dozens of other flavoring compounds raise similar concerns:

• Cinnamaldehyde (cinnamon flavors): cytotoxic to lung cells in lab studies
• Vanillin (vanilla flavors): produces oxidative stress when heated and inhaled
• Benzaldehyde (fruit flavors): respiratory irritant

What the Labels Don't Tell You

In my 10 years in the industry, here's what consistently surprised people:

There's no requirement to list all ingredients. Unlike food products, e-liquid manufacturers in most jurisdictions aren't required to disclose every chemical compound in their formulations.

"Lab-tested" means almost nothing. Most third-party lab tests check nicotine concentration and a few heavy metals. They don't test for thermal degradation products — the compounds created when those ingredients are heated.

Quality control varies wildly. I've visited state-of-the-art facilities and I've seen batches mixed in converted garages. Both products end up on the same store shelves.

Ready to Quit?

If this article has you reconsidering your vaping habit, you're already taking the first step. Here are the products I genuinely recommend for people ready to make the switch:

The combination of a patch (baseline) plus gum (for cravings) has the highest success rate of any NRT approach. Add a behavioral support app and your chances go up even further.

The Bottom Line

You deserve to know what you're putting in your body. The vape industry has spent years keeping this information vague, buried in safety data sheets, or hidden behind marketing language designed to reassure rather than inform.

Now you know. What you do with that knowledge is up to you — but if you're ready to quit, we're here to help.