Intense Hydrating Mask

The base most products are built on. It carries the other ingredients and has no safety concern.

A fatty alcohol derived from stearic acid that thickens creams and gives them a smooth, non-greasy glide. It is one of the fatty alcohols the CIR panel reviewed together and found safe as used, with a very low reported rate of contact sensitization.

A humectant that draws water into the skin. One of the best-studied, best-tolerated ingredients in personal care.

A silicone that gives a smooth, soft feel and helps hold water in the skin. Inert and well studied.

A fatty alcohol used to soften skin and stabilize creams. Despite the name, it does not dry the skin.

A fatty-acid and tocopherol-rich plant oil used as a hair and skin emollient; CIR's review of plant-derived fatty acid oils found no evidence of irritation or sensitization and a long history of safe use in food and cosmetics.

An undisclosed scent blend that can contain dozens of components. The single most common cause of cosmetic contact allergy, and the blend is not itemized, so you cannot see what is in it.

A modified guar gum used to thicken and stabilize emulsions and gels. It is derived from guar beans and is well tolerated when applied topically. It is common in skincare formulas where a smooth texture is valued.

A soothing humectant that helps skin and hair look conditioned. Very well tolerated.

A common emulsifier and texture-softener made from glycerin and stearic acid. CIR review of this class found no evidence of reproductive, carcinogenic, sensitizing, or phototoxic effects in the studies examined.

A blend of cetyl and stearyl fatty alcohols used to thicken lotions and soften skin. It is chemically unrelated to drying alcohols like ethanol, and the CIR expert panel has found fatty alcohols safe as used in cosmetics.

A natural, plant-based emulsifier made from cetyl alcohol and glucose that mixes oil and water phases in cosmetics. It is well studied, nonirritating in published testing, and presents no known safety concerns for cosmetic use.

A PEG-based emulsifier that blends oils and water in formulas. It is a workhorse ingredient in stable emulsions and is approved for cosmetic use. Well tolerated.

A positively charged conditioning polymer used in shampoos and conditioners to reduce frizz and improve manageability. It is well tolerated and has been safely used in cosmetics for decades.

A gentle surfactant derived from stearyl alcohol and ethylene oxide. It is used to stabilize emulsions and is well tolerated in rinse-off and leave-on formulas. Approved for cosmetic use.

Caprylyl glycol is a plant-derived humectant that also has mild antimicrobial properties, so it is commonly paired with other preservatives to allow lower overall preservative levels. Available data do not point to meaningful irritation or sensitization concerns at typical use levels.

A small humectant and solvent molecule that helps other ingredients dissolve and helps skin hold water. It is one of the most studied cosmetic ingredients and is considered safe at the concentrations used in personal care products.

Used in tiny amounts to set a product to skin-friendly pH. No concern at those levels.

A chelating agent that binds trace metal ions to keep formulas stable and preservatives working properly. It is not a functional skincare "active" and only a very small amount is used, with minimal skin penetration expected.

An olive-oil-derived emulsifier, almost always paired with cetearyl olivate, that holds water and oil together and leaves a light skin-like finish. It is well tolerated and graded low concern in published assessments.

Chlorphenesin is a preservative subject to an EU maximum concentration limit and has been linked to contact dermatitis in a minority of users, particularly with repeated exposure. Most people tolerate it at the regulated use level without issue.

A quaternary ammonium conditioning agent that coats hair with a positive charge to smooth the cuticle, cut static, and ease detangling; it is one of the most common conditioning ingredients in rinse-off conditioners. CIR reviewed it as part of the trimonium family and found it safe as used, including in leave-on formulas at typical concentrations.

A quaternary ammonium salt used as a conditioning and antistatic agent in hair products. It has been extensively documented as safe in cosmetics when used in typical rinse-off formulations.

A widely used preservative, safe at the legal limit of 1% or less. Often the "paraben-free" replacement.

Alpha-isomethyl ionone is a violet-scented fragrance material and one of the EU-listed allergens requiring label disclosure. Documented sensitization is more common with this ingredient than with many other listed fragrance allergens.

A floral fragrance component and one of the EU-labelled fragrance allergens. Usually fine, worth watching if you react to scented products.

Hydroxycitronellal is a lily-of-the-valley scented fragrance ingredient on the EU allergen disclosure list. It has well-documented sensitizing potential in patch-test studies, so it is worth checking the label if you have known fragrance sensitivities.