No.4 Icy Soothing Beauty Sheet Mask

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

A small glycol used as a solvent and to boost the absorption of actives, and to help preservatives work at lower levels. It is well tolerated and graded low concern in published assessments.

A light, low-odor glycol used as a solvent and humectant, extremely common in Korean toners and essences. It has a low reported irritation rate and is graded low concern in published assessments.

A glycol used very widely in Korean and Western skincare as a lightweight humectant, solvent, and gentle preservative-booster, often in place of traditional preservatives. It has a low reported irritation rate at use levels and is graded low concern in published assessments.

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

A lightweight humectant and solvent similar in role to propylene glycol, used to carry actives and give lotions a lighter feel. CIR has reviewed it and considers it safe as used in cosmetics.

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

A naturally occurring nucleoside used in anti-aging formulas, often marketed for smoothing the look of fine lines. It has a low irritation profile and no established hazard at cosmetic use 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.

Tea tree oil is used for its antimicrobial reputation in blemish-focused products, but it is a genuine, well-documented contact sensitizer, and its allergy potential rises sharply once the oil has oxidized from air exposure. Fresh, well-preserved, low-concentration formulations are much lower risk than old or improperly stored oil.

Carbomer is a synthetic polymer used purely to thicken and stabilize gels and lotions, with negligible skin penetration due to its large molecular size. Safety reviews have found low toxicity and minimal irritation potential even in leave-on use.

Xanthan gum is a microbial-fermentation-derived polysaccharide used to thicken and stabilize textures, similarly common in food. Cosmetic panel review of this and related microbial gums found them safe as used, with no meaningful irritation signal at typical concentrations.

A buffering agent used in tiny amounts to set a product's pH, most often alongside gel-forming polymers. It is graded low concern in published assessments at the levels used.

A plant extract long used in traditional wound care and now common in "cica" soothing products, valued for calming redness and supporting the skin barrier. It is generally well tolerated, with rare contact allergy reported.

A polysaccharide extracted from yeast cell walls or oat bran. Used for hydration and skin conditioning, beta-glucan is well tolerated with emerging evidence for supporting skin barrier function. No safety concerns flagged in cosmetic use.

A phospholipid emulsifier from soy or sunflower that binds water and oil and helps other ingredients absorb. It is a natural component of skin membranes, well tolerated, and reviewed as safe as used; a soy-derived grade is not a meaningful concern for a soy food allergy because the protein is largely absent.

Green tea extract is a well-studied topical antioxidant with a long history of use in serums and moisturizers, generally well tolerated at cosmetic concentrations. Panel safety reviews of Camellia sinensis-derived ingredients have not identified meaningful topical hazard.

A soothing plant extract traditionally used in skincare, valued for its potential anti-inflammatory properties. Published assessments note it is generally well tolerated in cosmetic formulations, though people with sensitivities to botanicals may want to patch test.

A plant-derived water or extract used mainly as a soothing humectant filler. Evidence for dramatic skin benefits beyond mild hydration and soothing is limited, but it is well tolerated by most people.

A broken-down form of hyaluronic acid with smaller molecules intended to penetrate more deeply into the skin. It functions as a humectant and is well tolerated, with the same safety profile as standard hyaluronic acid.

An aromatic plant extract rich in natural antioxidants, valued in skincare formulations for its protective properties. Published cosmetic assessments indicate it is generally well tolerated, though the botanical origin means some sensitive individuals may react.

Chamomile extract is used for its soothing and mild antioxidant reputation and is generally well tolerated. It belongs to the Asteraceae (Compositae) plant family, so people with a known ragweed or daisy-family allergy occasionally react to it and may want to patch test first.