Biolage Hydra Source Daily Leave-in Treatment Versus Biolage Hydra Source Daily Leave-In Tonic

Butylphenyl Methylpropional is a synthetic fragrance. You might know it as "lilial". The scent of this ingredient is floral-like and similar to the scent of lily flowers.

In March of 2022, the EU banned this ingredient in both rinse-off and leave-on products. This is because research found Butylphenyl Methylpropional to disrupt fertility in rats.

This ingredient is a preservative, antimicrobial, and emulsifier. It is often used in cosmetics for its ability to cleanse, condition, and reduce static.

Cetrimonium chloride is a quaternary ammonium salt, meaning it has a water-soluble structure.

Coumarins are a group of substances found naturally in plants. There are over 1300 types of coumarins identified. It has a natural vanilla scent.

Coumarin is an identified EU known allergy, meaning it may cause an allergic reaction when applied to the skin.

Disodium EDTA plays a role in making products more stable by aiding other preservatives.

It is a chelating agent, meaning it neutralizes metal ions that may be found in a product.

Hexyl Cinnamal is a fragrance ingredient with a similar scent to jasmine. It can be naturally found in chamomile essential oil.

This ingredient is a known EU allergen and may sensitize the skin. The EU requires this ingredient to be listed separately on an ingredients list.

Hydroxycitronellal is a fragrance created from citronellal. The smell of hydroxycitronellal is often described as "citrus-like" or "melon-like".

Hydroxycitronellal is a known EU allergen and may cause irritation when applied to the skin.

Limonene is a fragrance that adds scent and taste to a formulation.

It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".

Linalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.

Like Limonene, this ingredient oxidizes when exposed to air. Oxidized linalool can cause allergies and skin sensitivity.

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.

Propylene Glycol is an odorless, colorless liquid. As a humectant, it helps skin retain moisture. It also aids in delivering active ingredients.

Another role of this ingredient is preventing a product from melting or freezing. Propylene glycol also adds antimicrobrial properties to a product, elongating product lifespan.

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.