Colorstay Limitless Matte Liquid Lipstick Poster Child

A lightweight hydrocarbon that gives formulas a smooth, silky feel. Used in color cosmetics and sunscreens. Well tolerated and inert.

Trimethylsiloxysilicate is a silicone resin built from trimethylsiloxy and silicate units, used in makeup and skin and hair products to form a light, flexible film that adds body, wear, and a soft-focus finish. CIR's expert panel reviewed clinical and animal data on this and related silylates and concluded the ingredient is safe as used, provided the finished product is formulated so it isn't irritating to the eyes or respiratory tract when it's inhaled as a fine powder or aerosol.

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

A synthetic polymer used as a gentle exfoliant in scrubs and peeling products. It is an inert, non-biodegradable microparticle with no known skin irritation or sensitization potential when used topically in cosmetic formulations.

A naturally occurring mineral silicate that adds shimmer and light-diffusing properties to cosmetics. Cosmetic-grade mica is well tolerated and should be free of asbestos and talc contamination.

A quaternized clay mineral used to thicken and suspend products. CIR found it safe as used, though the mineral base means trace amounts of inhalable silica particles exist if the powder form is aerosolized. It is well tolerated in leave-on and rinse-off cosmetics when formulated properly.

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

A diester formed from malic acid and isostearyl alcohol. It conditions and smooths skin with no known safety issues in cosmetic use.

A linoleic-acid-rich plant oil used as an emollient and, in some small pediatric studies, associated with support of the skin barrier when applied to infant skin. It is well tolerated with a low reported rate of contact reactions.

A starch derivative used in cosmetics to thicken formulations and improve texture. It has been used safely in food and cosmetics for decades and shows low irritation potential across rinse-off and leave-on products.

A synthetic film-forming emollient that provides a protective, flexible layer on skin. Not absorbed and well tolerated with no documented safety issues in cosmetic use.

Propylene carbonate is a small, high-boiling solvent used to dissolve other ingredients and thin out formulas in products like lipstick, eyeshadow, and mascara. Undiluted material caused moderate skin irritation in testing, but at the concentrations actually used in finished products (generally under 20%), CIR's panel found it at most moderately irritating and reaffirmed it safe as used, with no meaningful sensitization or photoirritation seen.

A plant-derived emollient oil rich in ricinoleic acid, used in skincare for decades. Contact allergy has been reported but is uncommon relative to how widely it is used in leave-on products.

A humectant that holds water at the skin surface for a more hydrated look. No safety concern.

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 fragrance fixative and solvent found naturally in balsams and used to help scents last longer. It is one of the 26 EU-designated fragrance allergens, with documented but uncommon contact sensitization.

A citrus-scented fragrance component. Fine for most, but it oxidizes over time into a known contact allergen, so it must be labelled in the EU.

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

A naturally occurring acid used to preserve and adjust pH in cosmetic formulas. It is generally recognized as safe at cosmetic use levels, with mild irritation possible on broken or very sensitive skin at higher concentrations.

Mineral pigments used to add color to cosmetics. Iron oxides are FDA-approved colorants with a well-established safety record in cosmetic formulations.

A mineral UV filter and white pigment used in sunscreens and makeup. It sits on the skin surface rather than being absorbed, and major regulators consider it safe for topical cosmetic use.

An FDA-approved synthetic colorant commonly used in cosmetics and personal care products. A small proportion of individuals report sensitivity or allergic reactions, particularly those with existing dye sensitivities. Remains safe at approved cosmetic concentrations.