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Being created from coconut oil means Cocamidopropyl Betaine is hydrating for the skin.

While Cocamidopropyl Betaine was believed to be an allergen, a study from 2012 disproved this. It found two compounds in unpure Cocamidopropyl Betaine to be the irritants: aminoamide and 3-dimethylaminopropylamine. High-grade and pure Cocamidopropyl Betaine did not induce allergic reactions during this study.

EDTA locks them up so it's a neat little background helper ingredient.

Typical use is under 2% but numbers as high as 10-25% have been reported in hair color products.

The Cosmetic Ingredient Review panel looked at the whole family and concluded they're safe as used. At cosmetic concentrations, they have not been found to be skin irritants or sensitizers.

Clinical testing has found no absorption through skin so the scary-sounding oral toxicity numbers from animal studies aren't relevant to a face cream.

One real formulation note: this ingredient is a penetration enhancer so it can slightly increase how much of the other ingredients get through (though this is more of a thing for formulators to work around).

Allergy is genuinely rare; there are a handful of case reports so be sure to avoid if you're patch test positive to EDTA.

It's typically used at levels below 5% but can go up to 8.5% in hand cleansers.

Human irritation data for this ingredient looks good: a 2024 study found that Laureth-23 had the lowest irritation score of all the fatty alcohol ethoxylates tested.

Sensitization risk is also low for allergies, the CIR found:

The only notable finding was slight irritation of the clear membrane in the eyes of rabbits so that's worth knowing for eye-area products.

There is one caveat for this whole ingredient family: ethoxylated surfactants slowly oxidize when exposed to air, and it's the oxidation products, not the fresh material, that act as sensitizers.

A study that patch tested 528 dermatitis patients found stronger reactions to the oxidized surfactants; this is mostly a formulation and shelf life issue.

This ingredient does have a comedogenic rating of 3, but this doesn't mean a formula with this ingredient will clog pores. Human testing has proved that any finished product with this ingredient won't automatically make you break out; it really comes down to concentration, formula, and your skin.

The chemistry for this ingredient is reassuring; Malassezia uses long chain fatty acids from its surroundings (C11-24) to grow, and Laureth-23 has no fatty acid for it to grab onto.

Supporting this, closely related alkyl PEG ethers like Ceteth-20 get used in Malassezia lab work as neutral carriers to disperse a separately added fatty acid (not as the food source itself).

A 2012 assessment found this ingredient is used in leave-on products at up to 21%, which is at the very high end for the category; most cosmetic use is far lower and typically in the single digits.

A true allergy to Laureth-4 is rare; similar alcohol ethoxylates tested negative for skin sensitization in undiluted guinea pig studies, and related compounds were non-sensitizing in Magnusson-Kligman maximization tests.

There is one caveat for this whole ingredient family: ethoxylated surfactants slowly oxidize when exposed to air, and it's the oxidation products, not the fresh material, that act as sensitizers. This is mostly a formulation and shelf life issue.

Dr. James Fulton's rabbit ear test from the 1980's scored this ingredient as a 5 on the comedogenic scale. Fulton himself described the rabbit ear as not an ideal model and the tests used undiluted ingredients on rabbit ears, which are more reactive than human facial skin.

Dr. Draelos later used a human assay on finished cosmetic products and found that products built with so-called comedogenic ingredients are not necessarily comedogenic themselves.

This ingredient can be potentially pore clogging if it appears high in the ingredient list of a leave-on product.

The fungal acne picture is actually reassuring: Malassezia uses fatty acids from its surroundings (C11-24). This ingredient has nothing for the Malassezia yeast to use since it is an alcohol and not an acid.

Supporting this, closely related ethoxylated alcohol detergents like Ceteth-20 get used in Malassezia lab work as neutral carriers to disperse a separately added fatty acid (not as the food source itself).

The EU requires it to be named on the label above 0.001% in leave-on and 0.01% in rinse-off products.

Fresh linalool is a weak sensitizer but air exposure turns some of it into hydroperoxides, which are strong sensitizers. Those oxidation products are the actual allergy concern.

Patch-test clinics see positive reactions to linalool hydroperoxides in about 4% to 12% of dermatitis patients depending on country and test concentration.

Resassuringly, one analytical study found hydroperoxide levels in real fragranced products to be orders of magnitude below what induced sensitization in animal studies with no evidence of oxidation building up during normal storage.

The practical takeaway is that linalool is fine for most people but worth avoiding if you have a confirmed fragrance contact allergy or a badly compromised barrier.

Products stored a long time after opening are also the high-risk scenario since that is when oxidation happens.

The scent of linalool is described as floral, spicy tropical, and citrus-like.

For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.

The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.

For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.

One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.

Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.

Parfum can also be used to mask or cover an unpleasant scent.

The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.

Due to its large molecule size, it doesn't penetrate beyond the skin's surface.

This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.

A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.

As an emollient, it helps trap moisture in the skin. It is considered an occlusive.

The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

It is commonly used in food. It should be noted sodium sulfite degrades both vitamins B1 and E.

Fun fact: Sulfites are naturally occuring in wine.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!