| What is it? |
Euxyl® PE 9010 is a very popular preservative that you’ll find in tons of commercial products, including eye makeup, lip makeup, products marketed for sensitive skin, and baby products (though Simply Ingredients notes it not recommended for use in diaper-area products for children). It is 90% phenoxyethanol and 10% ethylhexylglycerin with a small percentage of tocopherol (source). PE = phenoxyethanol & ethylhexylglycerin; 9010 = the usage ratios. Due to its phenoxyethanol content it is not natural, but is often considered ‘more’ natural than Liquid Germall™ Plus. Euxyl® PE 9010 is made by Ashland, but this blend of ingredients is manufactured by many different companies and sold under many names. As always, if any of the information from your supplier contradicts information I’ve shared here, defer to your supplier. Many sources describe Phenoxyethanol (and) Ethylhexylglycerin as being broad spectrum (Ashland, Simply Ingredients, Lotion Crafter, Evonik, Arxada), while others say it is weak on fungi. As with all preservatives, the only way to really know if it works for your formulation is to try it and test it, but you can improve chances of success by including a chelator, reducing water activity, and lowering the pH below 5. |
| INCI |
Phenoxyethanol (and) Ethylhexylglycerin |
| Appearance |
Clear liquid |
| Usage rate |
0.6–1% |
| Scent |
Nothing really noticeable, especially in a finished formulation. |
| Approximate Melting Point |
Liquid at room temperature |
| Effective pH range | Generally, really broad. Listed ranges usually start around 2–3 and go up to 10–12, depending on the manufacturer/source.
Ashland says 3–12. |
| Charge compatibility |
Effective in anionic, cationic, and non-ionic environments. |
| Solubility |
Due to its phenoxyethanol content, Euxyl® PE 9010 has limited solubility in water, but good solubility in ethanol, isopropanol, ethylene glycol, propylene glycol, butylene glycol, and glycerin. Because of its limited water solubility, Euxyl® PE 9010 isn’t a great choice for preserving really watery formulations like hydrous serums unless you include an adequate solvent or solubilizer. |
| Why do we use it in formulations? |
Euxyl® PE 9010 preserves our formulations so they don’t grow mould and get all gross and icky. |
| Do you need it? |
No, but it is a good preservative choice and I like having it on hand. |
| Refined or unrefined? |
Euxyl® PE 9010 only exists as a refined product. |
| Strengths |
Excellent global availability, good heat stability, broad effective pH range. |
| Weaknesses | Poor water solubility makes it a bit trickier to use in watery formulations (toners, mists, serums) when compared to Liquid Germall™ Plus.
High levels of ethoxylated surfactants can reduce efficacy. It is really common to find this preservative used in formulations that contain ethoxylated surfactants, solubilizers, and emulsifiers, so keep the potential for decreased efficacy in mind, but I wouldn’t worry about levels below 5%. I’m not saying 5% is a limit by any means, though! As with any preservative system, you will have to test and see if it works in your formulation. It’s not great against fungus, but I have generally had good experiences with it. As with all preservatives that contain phenoxyethanol, Euxyl® PE 9010 can thin emulsions—though just how much thinning you’ll experience can vary a lot with the formulation. |
| Alternatives & Substitutions |
You’ll need another broad spectrum preservative. I use Liquid Germall™ Plus a lot; it is more water soluble than Euxyl® PE 9010 but has a lower heat tolerance. Optiphen™ (INCI: Phenoxyethanol, Caprylyl Glycol) and Optiphen™ Plus (INCI: Phenoxyethanol, Caprylyl Glycol, Sorbic Acid) could be good options. I have found Optiphen™ Plus is even less water soluble than Euxyl® PE 9010 due to its caprylyl glycol content, so if you are looking to preserve a mostly-water formulation you may need more solvent/solubilizer for Optiphen™ Plus than you did for Euxyl® PE 9010. Plain phenoxyethanol can also work, depending on the formulation, but I would recommend pairing it with an ingredient to lower water activity (like ethylhexylglycerin, caprylyl glycol, pentylene glycol, propanediol 1,3, butylene glycol, etc.). |
| How to Work with It |
Euxyl® PE 9010 can be hot or cold processed. Ashland says it is stable up to 120°C (248°F), while other manufacturers list 80°C (176°F) as the maximum temperature. I’ve had great experience using it in emulsions (though it can cause thinning) and low-water content formulations like shampoo bars and conditioner bars. If you want to use Euxyl® PE 9010 in a watery formulation like a hyaluronic acid serum, pre-distribute it in a suitable solvent (glycerin, propylene glycol, and propanediol 1,3 are probably the easiest options) before adding the water. I’d try using 3–5x the amount (eg. 1% Euxyl® PE 9010, 3–5% solvent) and see how that works. (This strategy was suggested to me by cosmetic chemist Valerie George from Simply Ingredients.) |
| Storage & Shelf Life |
Stored somewhere cool, dark, and dry, Euxyl® PE 9010 should last 3 years. |
| Tips, Tricks, and Quirks |
There are many different products in the Euxyl® line and they are not interchangeable. Pay attention to the INCI of what you’re buying and using! There are also many INCI-identical preservatives out there, including:
You cannot assume any preservative with the same INCI is just Euxyl® PE 9010 under a different name, which means you also cannot be certain it will perform identically. Make sure you research and test! |
| Recommended starter amount |
30g (1.06oz) |
| Where to Buy it |
Buy it from an online DIY ingredient supplier.
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Want to learn more about preservatives and compare them? Check out this chart!