It shouldn’t be too hard to find out what’s going into your e-juice liquid. After all, that stuff’s going into your body, right? And the truth is that most reputable brands have an ingredient list, and if you got some liquid cheap and it didn’t tell you what was in it, you’d avoid it, right?

But would you know what to look out for in an ingredient list that might mean your e-cigarette is actually harming you? The truth is that a lot of e-juices have flavorings, and those flavorings aren’t what you’d call ‘all-natural’. So what should you avoid?


This flavoring chemical makes things taste buttery without having to add actual butter. Perfect for modern life, right? All the taste, none of the calories. And that’s true when you’re munching on cinema popcorn or searching for something else to put on your baked potato.

Except scientists don’t know what happens when you’re inhaling the chemical instead of eating it. It’s even been linked to obstructive lung disease. Your favorite flavor might have this chemical in huge amounts, so it’s best to check any new bottles you get to make sure there’s no diacetyl anywhere near it.


Once manufacturers woke up to the fact that diacetyl caused the charmingly named ‘popcorn lung’, they started searching around for alternatives. Acetoin still has that buttery taste which enhances tastes like apple and maple syrup, but companies believed it would be able to do that without putting customers at risk.

Unfortunately, they were wrong. It’s not just similar enough to diacetyl to taste a little like butter—it can actually be just as harmful. Research has also found evidence to suggest diacetyl turned into acetoin in the body before it infected the lungs of hapless smokers.


‘Hmm,’ you might be saying. ‘I’ve heard of acetone before.’ You’re thinking of the stuff that melts away the plastic in nail polish, right? Yeah, it’s also used in paint thinner. And even in some e-liquid flavoring.

Evidence of this chemical was found in a 2014 study which investigated the components of various e-liquids around the States. If you suck down something which eats away even plastic glitter on skin, you might find that your lungs will start complaining.

Acetyl propionyl

This chemical is responsible for any e-liquid smelling sweet, nutty, or like caramel. However, as with its friends acetoin and diacetyl, it turns out it’s not good for you when you’re inhaling it. Not only can it damage your respiratory tract, it can also cause pads of tissue to raise on the lungs and make breathing for difficult, studies have show that it can literally genetically change animals’ brains.

These chemicals are collectively known as diketones, in case an e-juice manufacturer attempts to fool you by putting that on their product.

Ethylene Glycol

Sweet chemicals that are actually bad for you. Seems to be a common theme in e-liquid. Some manufacturers will put this into their e-juice to add to the sweet hit, but unfortunately it’s one of the things that makes antifreeze so dangerous. When the body breaks down the vapor, little toxic chemicals trickle into your blood and can make you very sick.


Acrolein is often a by-product of e-juice flavorings, but your body ingests it. It’s used a contact herbicide to kill weeds and, in normal cigarettes, can increase the risk of lung cancer. It’s toxic in its whole form, and although eating it in small quantities won’t harm you, the same can’t be said for inhaling it. It’s a strong irritant for the skin, eyes and nose, so if one of your e-juices always leaves you with stinging eyes and a steaming nose, you might need to stop using it no matter how great it tastes.

Unfortunately, it can be tough to know what’s actually in your bottle. That’s why Black Note are open and upfront about our ingredients, even producing a lab report to make sure our customers know exactly what’s in our flavors, which are all rich and authentically flavored with genuine tobacco.

Remember to always read the bottle carefully, and if you can’t pronounce it, don’t smoke it.