Butylene Glycol: Natural or Synthetic? Safe or Dangerous? Learn What This Ingredient Really Is, What it Does, and Where it Comes From

This is a common ingredient in many skincare, haircare, and other wellness and beauty products. It has a ~*•ºchemichallyº•*~ sounding name and is synthetically made, but it may be a much more Natural ingredient than you may think. Everything is a chemical. If you looked up the chemicals in an apple you’d find they’re just as hard to understand as your average overly-processed frozen dinner.

This chemichal was originally derived from

What is it?

Butylene Glycol is a type of Alcohol. It has several uses:

  • Adds hydration to products
  • Acts as a Solvent
  • Balances texture

An Example of a Product Formulated With Butylene Glycol

Water (Aqua), Methylpropanediol (hydration), Butylene Glycol (hydration), Salicylic Acid (beta hydroxy acid/exfoliant), Polysorbate 20 (stabilizer), Camellia Oleifera Leaf Extract (green tea/skin calming/antioxidant), Sodium Hydroxide (pH balancer), Tetrasodium EDTA (stabilizer).

The popular skincare product 2% BHA Liquid Exfoliant by Paula’s Choice uses this ingredient. It’s listed 3rd, so it’s one of the ingredients that make up the base of the product.

So why is in this particular product?

It helps combat the potential drying effects of Salicylic Acid, and helps make the texture of the product feel watery, but not too watery. This ingredient also helps keep the Salicylic Aciddissolved, since it can’t be dissolved in water, which is a common challenge in formulating a Salicylic Acid product is keeping it from separating.

Butylene Glycol also increases the permeability of the skin, allowing moisture and active ingredients to penetrate deeper.

The company Paula’s Choice actually has an informational page on this ingredient. Take a look if you’d like to see how/why they use it. I was pleasantly surprised to find that they even have an Ingredient Dictionary to help customers understand what’s in the products. Despite this feature being a bit hidden, the information is presented well.

Is it Safe?

It has been used in skincare for many years and there are no known health risks accosted. If you google around you may find warnings from unnamed “Skincare Experts” about it causing birth defects, however, I did some digging and found that the only evidence of this was one single study in 1844 done on mice. Since Butylene Glycol was invented in 1942, that’s already a huge inconsistency. I couldn’t even find the original study, which speaks to just how credible these claims are. I couldn’t even find articles that shared their sources on the “Experts” they consulted. I would disregard these claims.

I’ve observed a strange phenomenon in marketing with what I’m dubbing “Ingredient Which Hunts”. This is when a common ingredient suddenly has a bunch of propaganda about how dangerous it is and why it’s not “Clean” or “Green” or “Organic” or “Natural”. This causes brands using the ingredient-in-question to loose sales to the brands who can slap a “Does Not Contain X” label on their product. The most common examples I can think of are GMOs, or MSG in Asian cuisine. This is a delicate dance under the Sword Damocles for the industry though.

When you start falsely claiming a common, safe ingredient is dangerous in order to thwart competition, you just make it worse for everyone in the long run. This means that un-educated consumers will be confused about what is or isn’t safe. It also means that you’ll raise prices for both the consumer and other businesses, at least temporarily. This is due to the fact that switching out a staple ingredient isn’t easy, and there may or may not be a suitable alternative readily available.

How Common is it?

To illustrate how common this ingredient is, check out this hyper-specific google search for this ingredient within Sephora’s website. There are over 3.6K results for everything containing the exact text “Butylene Glycol” AND “Ingredients”.

Sephora claims to carry over 45K products. I can estimate via this other ultra-specific google search, that of that 45K, about 11.7K products contain an ingredient list. This means I’m not including non-consumable products in my comparison. Things like makeup brushes, hair tools, candles, face managers, etc. won’t count.

This means that about 1/3 of Sephora’s cosmetic/skincare/haircare products contain this ingredient. That’s how many high-end luxury brands are betting their bottom line that it’s safe for skin if that gives you peace of mind in terms of safety.

I couldn’t just search within Sephora itself. I discovered that you can only search for ingredients on their site that they market. For example if you search “green tea extract” or “retinol” or “salicylic acid” you’ll get results. If you just go search for any random, non-marketed ingredient from any list on any of their products, they won’t show any results.

I’m sure this is on purpose. But you can sidestep this barrier of information by using google search “hacks” to search within a single site.

My Experience With This “Chemical”

When I purchased some Butylene Glycol of my own, I discovered that on the bottle it said “typical use level 1% – 10&” to give some context to how it’s used in formulas. This is the one I purchased. The relatively low concentration, and high prevalence within beauty industry products lead me to the conclusion that even a small quantity could be used to create an array of skincare products at home.

It’s entirely safe to put it on your skin. If it can be in products in a concentration of up to 10%, and it’s in about 1/3 of products out there, then I’d certainly know if I’d have a bad reaction by now. Understanding this context allows me to know the relative safety of an ingredient without necessarily having to look anything up.

If you pour pure Butylene Glycol directly onto the skin it has a viscosity similar to a thick oil, but it feels slightly sticky and it spreads deep into the cracks of the skin very easily. It has an extremely faint plastic smell that is not unpleasant. You need to put your nose right on top of it to smell anything at all, it’s very faint. The substance itself is completely clear and colorless.

I’ve read that it has a sweet flavor, however I did not taste it. I have read nothing about it being safe to ingest, so I recommend you don’t drink it.

It’s Gotten a Bit of a Bad Rep (Undeservingly)

Honestly the poor branding of this substance has gotten it a lot of bad press. And by bad, I mean the science reporting is abysmal.

Here’s a quote from some website called The Science Times. One of the many I found making this claim without a valid source to speak of.

The Cosmetic Ingredient Review panel, a group that oversees the safety of the ingredients in skincare products, has determined that butylene glycol is safe to use. However, some experts still caution people using products containing clear substances to be careful as it might trigger some allergies.

So . . . . Last time I checked we don’t just eyeball the color of a chemical to determine its safety. This is highly unscientific. I don’t know who these “Experts” are, but the only thing they’ve got expertise in is clickbait.

You can have an allergy to anything, however there are extremely few documented cases of people having allergies to Butylene Glycol. The fact that ingredients lists are hard to understand by design would indicate that people are likely unable to properly diagnose the precise origin of their allergic/irritated reactions to products.

Just think about it, if you had a poor reaction to a product, and you wanted to check the ingredients to see what the culprit was, how likely is it that you’ll even be able to understand the full list? Almost Zero. Without a ton of research that is.

Where Does it Come From?

Let’s start with the basics. Butylene Glycol is an ORGANIC (yes, that’s correct) chemical.

Organic Chemistry –– the chemistry of carbon compounds (other than simple salts such as carbonates, oxides, and carbides).

In plain English this means that these are chemicals that our found in nature that exist within our bodies, or the bodies of plants and animals naturally. This is the chemistry of life itself. You don’t get more natural than that. We are carbon based life forms, and thus to study carbon compounds is to study the architecture of our own being.

It was first synthesized in 1942 by fermenting corn. It’s a byproduct created by the bacteria of the fermentation process. This is the actual study I found listed in The Library of Congress. Look at that, citing an actual study, is it really that f*ing hard CNN?

It was originally cited as a means to manufacture Antifreeze, to be used as an industrial solvent in various product manufacturing process, and to even make rubber.

Don’t let the Antifreeze thing scare you though. It’s not an ingredient in Antifreeze, but a precursor. That means that the Butylene Glycol is turned into a different substance via chemical reaction. Think about this similarly to table salt, one of its two components is Chloride, which if ingested is deadly, however when it reacts with potassium, the resulting substance (table salt) is entirely different and safe. When they add it to Antifreeze it’s not even the same substance anymore. There’s nothing to be afraid of, you’re not actually putting Antifreeze on your skin.

Since it’s a byproduct of fermenting Corn, Butylene Glycol is no more un-natural than a glass of red wine 🍷.

Since the 40s however, we’ve learned other ways of producing it by fermenting other things. If you’d like to learn more in-depth about the process of synthesizing it, you can check out Brontide a company working to produce Butylene Glycol in a more sustainable way.