Mousse & Foam
Mousse & Foam
British United Kingdom
American United States

What's inside

What's inside

Benefits

Concerns

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Preservative

Diazolidinyl Urea is an antimicrobial preservative. It is commonly used to prevent bacterial, yeast, and mold growth.

Diazolidinyl Urea slowly breaks down into formaldehyde, an effective microbe killer but also a known allergen/carcinogen.

Some people who are allergic to imidazolidinyl urea also react to diazolidinyl urea. It ranked as the 14th most common allergen in patch tests from 2005–06.

Safety reviews show that at concentrations under 0.5%, the formaldehyde released remains below the accepted safety limit, making it considered safe for cosmetic use.

Ultimately, its safety depends on individual skin sensitivity and personal comfort with formaldehyde-releasing preservatives.

Learn more about Diazolidinyl Urea

This ingredient is a low-molecular weight gas using as a propellant in foams, sprays, and mousses.

It is not intended to interact with skin in a meaningful way as it evaporates almost immediately after dispensing and only leaving behind the actual product formula.

If it does somehow make it onto your skin, it is chemically inert and does not penetrate or get absorbed into skin. Safety assessments note that adverse skin reactions to this ingredient are uncommon.

Learn more about Isobutane
Masking, Perfuming

Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.

Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.

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.

Learn more about Parfum
Skin Conditioning

PEG-12 Dimethicone is a type of water-soluble silicone. It has skin conditioning and hydrating properties.

According to a manufacturer, this ingredient's stability is decreased by strong acid or alkali.

Emulsifying, Surfactant

Polysorbate 80 is a synthetic surfactant and emulsifier derived from sorbitol and oleic acid.

It reduces the surface tension between oil and water phases to help them stay mixed and stable in a formulation. In other words, it prevents your formulas from separating into an oily mess.

The CIR Expert Panel has evaluated the scientific data and found this ingredient to be safe, non-irritating, and non-sensitizing at concentrations up to 5% (it's even approved by the FDA as an OTC eye drop ingredient).

Learn more about Polysorbate 80

Propane is a gas derived from petroleum and natural gas. In cosmetics, its only used as an aerosol propellant (it pushes your product out of the can when you press the nozzle).

That's why you'll find it in hair sprays, dry shampoos, deodorants, mousses, shaving foams, and sunscreen sprays.

It is volatile, meaning it only remains on skin for less than 10 seconds before evaporating. It doesn't really linger long enough on skin to act as a skincare ingredient in any meaningful way.

Hairspray concentrations are between 6-17%.

The CIR Expert Panel concluded it to be safe as a cosmetic ingredient under present concentration and usage.

Learn more about Propane
Humectant, Skin Conditioning, Solvent

Propylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.

As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.

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.

Learn more about Propylene Glycol
Skin Conditioning, Solvent

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

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!

Learn more about Water

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