Aesop Parsley Seed Anti-Oxidant Intense Serum Versus Aesop Lightweight Facial Hydrating Serum

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.

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

Peg-40 Hydrogenated Castor Oil is derived from castor oil and polyethylene glycol (PEG). It is used as a emollient and emulsifier.

As an emulsifier, it helps prevent ingredients from separating. It also helps make the other ingredients more soluble; it is often used to solubilize fragrances. This increases spreadability and elongates shelf life in a product.

Polysorbate 20 is made by combining ethoxylation of sorbitan, ethylene oxide, and lauric acid. It is a mild cleansing agent, surfactant, and emulsifier.

As a surfactant, it helps collect dirt and oils for washing. Emulsifiers prevent oils and water from separating.

Polysorbate 80 is a surfactant and emulsifier. It is used to keep ingredients together, and prevent oils and waters from separating.

It is made from polyethoxylated sorbitan and oleic acid. This ingredient can be found in cosmetics, foods, and medicine. It is water-soluble.

This ingredient is a preservative with antimicrobial properties. It is the sodium salt of dehydroacetic acid.

It is especially effective at preventing bacterial and fungal growth in low concentrations.

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.