In 2016, the FDA finalized a rule extending the Center for Tobacco Product’s authority to cover all tobacco products, including electronic nicotine delivery systems (ENDS). As a result, the FDA has assumed responsibility for regulating all aspects of ENDS, including the mixture of ingredients that end up in e-juice and vape cartridges.

So, what’s in your vape?

It’s hard to know for sure, but what we do know is that most e-cigarette liquids (also known as “vape juice”) use a standard combination of ingredients:


Nicotine is the chemical found in tobacco products that is responsible for addition. When using tobacco products, nicotine is quickly absorbed into the body and goes directly to the brain, where is triggers areas associated with happiness and satisfaction. Teens are especially susceptible to nicotine’s addictive effects.

Propylene Glycol

Used primarily in food and beverage and pharmaceutical industry, propylene glycol (PG) is added to e-liquids to produce a thick cloud of fog. PG mixes well with flavorings and other additives and creates a vapor when heated. It is also a minor irritant, which replicates the sensation of inhaling cigarette smoke.

Vegetable Glycerin

Although it is almost exclusively derived from plant products, vegetable glycerin (VG) doesn’t offer many benefits. It is predominately used as a food additive to impart a sweet flavor and help food products retain moisture. So why is it added to e-juice? Vegetable glycerin is used to produce an even thicker, more voluminous cloud of vapor. The higher the concentration of VG, the denser the plume of smoke.


Natural and artificial flavorings are ubiquitous in products ranging from snacks and soft drinks to toothpaste and cough syrup, but they’re an especially important selling point for vaping. Flavorings typically fall into a few categories: Sweet, fruity, savory, spicy, minty, or traditional tobacco.

The above ingredients makeup the foundation of most e-juices, but they can be added in different proportions to achieve varied effects: A higher proportions of PG results in less vapor and more of a sensation after inhaling, while higher VG ratios products a greater volume of vapor.

And although these additives are considered Generally Recognized as Safe (GRAS) by the Food and Drug Administration (FDA), the long-term effects of inhalation remain unclear. The Center for Disease Control and Prevention warns that aerosol from e-cigarettes is not merely harmless “water vapor” and can contain potentially harmful substances including ultrafine particles, diacetyl (a flavoring agent linked to lung disease), and heavy metals such as nickel, tin, and lead.