Substitutions For Cyclomethicone
Author: Susan Barclay-Nichols
Thursday, July 5, 2018


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The silicone we call cyclomethicone can be one of three cyclic or “closed loop” versions, the name of which is based on the number of repeating silicone-oxygen units in the molecule. Cyclotetrasiloxane or D4 has four repeating units; cyclopentasiloxane or D5 has five repeating; and cyclohexasiloxane or D6 has six repeating. The cyclomethicone we buy is generally 95% + D5, up to 0.1% D4, and up to 4% D6.

Why is cyclomethicone so ubiquitous? It’s a very light, non-greasy, silky emollient with excellent spreading properties for hair and skin. It appears matte in moisturizers, sera, and primers, and doesn’t build up on hair.

If it’s so awesome, why are we trying to replace it? Because REACH, the EU’s chemical management program, recently decided “after 31st January 2020, the concentration of D4 & D5 in cosmetic products that are rinsed off after application (“wash-off”) should be less than 0.1% by weight of either substance,” as it’s considered detrimental to the environment. (The commission noted leave on products aren’t a concern as cyclomethicone is volatile, meaning it evaporates at room temperature, and rinses off during normal cleansing routines.) They concluded D4 is “persistent, bioaccumulative and toxic (PBT) and very persistent, very bioaccumulative (vPvB) substance”, while “D5 meets the criteria for a vPvB substance.” What does this mean? These are “a class of chemicals that resist degradation and persist in the environment for extensive periods.”

There’s general agreement about the environmental concerns about D4, but not so much when it comes to cyclopentasiloxane. Environment and Climate Change Canada concluded that, “siloxane D5 is not harmful to the environment,” while Australia noted it’s persistent and bio-accumulative.

For D6, Australia considers it persistent, while the UK considers it “not readily biodegradable and so meets the screening persistent (P) or very persistent (vP) criteria.” Canada stated, “Based on the available information on its potential to cause ecological harm, it is concluded that D6 is not entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment.”

You may see it said cyclomethicone is hazardous, but this word refers only to its category when being shipped as it has a low flash point of 171°F, on par with some fragrance or essential oils, but far below dimethicone’s 599°F or virgin olive oil’s 410°F. It’s been affirmed again and again by so many different agencies and studies that it is safe for our hair and skin. The Scientific Committee on Consumer Safety concluded in 2010, “cyclomethicone (D4, D5) does not pose a risk for human health when used in cosmetic products.” The Cosmetic Ingredient Review noted, “Minimal percutaneous absorption was associated with these ingredients and the available data do not suggest skin irritation or sensitization potential…The CIR Expert Panel concluded that these ingredients are safe in the present practices of use and concentration.”

If you’re concerned about using cyclomethicone, what can you use instead? There isn’t a one-size-fits-all answer: What we choose depends on what it brings to the party. One product might be all about the non-greasiness and matte appearance, while another might need a silky and powdery skin feel.

When it comes to choosing oils, good substitutes would be those considered dry and light, such as caprylic/capric triglycerides, meadowfoam seed oil, macadamia nut oil, hazelnut oil, evening primrose oil, and up to 5% isopropyl myristate.

I make a super simple yet decadent body oil with 33% IPM, 33% MCT, 33% sesame seed oil, and 1% essential or fragrance oil, which is non-greasy, light, and silky.
Tucuma butter is said to have a “silicone like” skin feel, and babassu oil is simply luxurious, non-greasy and silky. These can be used as part or all of the oil phase in an emulsion, emulsified scrub, or anhydrous product, alone or in combination.

Adding a powder, like tapioca starch, arrowroot powder, or Crafters Choice™ Slick Fix - Oil Locking Powder, to a lotion or anhydrous product reduces greasiness and increases glide, as do treated sericite micas or silica microspheres. Clay can have that effect, but it’s best to save it for dry masks or body powders as it’s hard to preserve in lotions and creams.

In my favorite anhydrous eye shadow primer stick, I’ve mimicked the properties of cyclomethicone by combining caprylic/capric triglycerides, IPM, mango butter, 3% Slick Fix - Oil Locking Powder with 15% Crafter's Choice Matte White Pigment Powder - For Oil to give me a nice white base for all my vivid, shiny colors.

Hair care products are the hardest substitutions as it’s used in all kinds of conditioners, anti-frizz products, and heat protecting sprays as it helps distribute all those lovely botanicals, proteins, and vitamins more evenly, and acts as an emollient without making hair look or feel greasy. Choosing a very light to light oil or ester will work well for all but the oiliest or finest hair types.

When formulating a conditioner or lotion, using Crafter's Choice Emulsifying Wax – conditioning results in an emulsion with a powdery, silky hair or skin feel, to which you can add silk amino acids, Honeyquat, or a very light oil to increase slip and glide.

I admit it’ll be hard for me to re-formulate some of my favorite as it has become a staple in my workshop, but if I keep in mind which properties I’m hoping to emulate, experiment a lot, and gift many samples on my testers for feedback, I’m sure I’ll be saying cyclomethicone schmyclomethicone before you know it!