silicon dioxide
AKA “Silica, Dioxosilane, 7631-86-9, Silicic anhydride, Diatomaceous silica, Wessalon, Zorbax sil, amorphous, colloidal
Ingredient
Ingredient Facts
Silicon dioxide
AKA: Silica, Dioxosilane, 7631-86-9, Silicic anhydride, Diatomaceous silica, Wessalon, Zorbax sil, Amorphous, Colloidal
Ingredient · Skin Conditioning · EWG: 4
Synthetic
Skin Conditioner
Not Clean
Silica is another name for the chemical compound composed of silicon and oxygen with the chemical formula SiO2, or silicon dioxide. There are many forms of silica. All silica forms are identical in chemical composition, but have different atom arrangements. Silica compounds can be divided into two groups, crystalline (or c-silica) and amorphous silica (a-silica or non-crystalline silica). c-Silica compounds have structures with repeating patterns of silicon and oxygen. a-Silica chemical structures are more randomly linked when compared to c-silica. All forms of silica are odorless solids composed of silicon and oxygen atoms. Silica particles become suspended in air and form non-explosive dusts. Silica may combine with other metallic elements and oxides to form silicates.
Solubility Insoluble (NIOSH, 2024)
Formula
O2Si
Mol. Weight
60.08
CAS #
7440-21-3
Form
Powder
State
Transparent to gray, odorless powder. Irritating to the skin and eyes on contact. Inhalation will cause irritation in the respiratory tract. [Note: Amorphous silica is the non-crystalline form of SiO2
See origin →
Functions
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Physical Exfoliant
Anti-Aging Benefits
Antioxidant Protection
Reduces Inflammation
Gently polishes surface
Traditional Use
Used historically as an absorbent and mattifying agent in mineral-based cosmetics and traditional powder formulations. Modern cosmetic-grade silica is produced synthetically and valued for its oil-absorbing, anti-caking, and texture-improving properties.
Skin Types
all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
EWG
4
CIR
Safe w/Qualifications
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
all-shades-safe
Regulatory Status
USApermitted
EUrestricted
JAPANrestricted
CANADArestricted
Safety assessment of borosilicate glasses as used in cosmetics.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of borosilicate glasses as used in cosmetics.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of borosilicate glasses as used in cosmetics.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of borosilicate glasses as used in cosmetics.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of borosilicate glasses as used in cosmetics.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of borosilicate glasses as used in cosmetics.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of silylates and surface-modified siloxysilicates.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of silylates and surface-modified siloxysilicates.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Safety assessment of silylates and surface-modified siloxysilicates.
Becker LC, Bergfeld WF, Belsito DV, Hill RA, Klaassen CD et al.
International journal of toxicology, 2013
Effects of Colloidal Oatmeal Topical Atopic Dermatitis Cr...
Kimberly Capone, Frank Kirchner, Shifra Liba Klein, Neena K Tierney
Journal of drugs in dermatology : JDD, 2020
Effects of Colloidal Oatmeal Topical Atopic Dermatitis Cr...
Kimberly Capone, Frank Kirchner, Shifra Liba Klein, Neena K Tierney
Journal of drugs in dermatology : JDD, 2020
Amended Safety Assessment of Silicates as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Amended Safety Assessment of Synthetically Manufactured Amorphous Silica and Hydrated Silica as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Final Report on the Safety Assessment of Aluminum Silicate, Calcium Silicate, Magnesium Aluminum Silicate, Magnesium Silicate, Magnesium Trisilicate, Sodium Magnesium Silicate, Zirconium Silicate, Att
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Final Report on the Safety Assessment of Potassium Silicate, Sodium Metasilicate, and Sodium Silicate
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Final Report on the Safety Assessment of Silica, Alumina Magnesium Metasilicate, Aluminum Calcium Sodium Silicate, Aluminum Iron Silicates, Hydrated Silica and Potassium Aluminum Silicate
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Safety Assessment of Borosilicate Glasses as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Safety Assessment of Silylates and Surface-Modified Siloxysilicates
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Alumina Magnesium Metasilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Aluminum Calcium Sodium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Aluminum Iron Calcium Magnesium Germanium Silicates
European Commission
EU Cosmetic Ingredient Database (CosIng)
Aluminum Iron Calcium Magnesium Zirconium Silicates
European Commission
EU Cosmetic Ingredient Database (CosIng)
Aluminum Iron Silicates
European Commission
EU Cosmetic Ingredient Database (CosIng)
Aluminum Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Ammonium Silver Zinc Aluminum Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Calcium Magnesium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Calcium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Calcium Sodium Borosilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Calcium Titanium Borosilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Dimethicone/Vinyltrimethylsiloxysilicate Crosspolymer
European Commission
EU Cosmetic Ingredient Database (CosIng)
Dimethiconol/Methylsilanol/Silicate Crosspolymer
European Commission
EU Cosmetic Ingredient Database (CosIng)
Dimethiconol/Silica Crosspolymer
European Commission
EU Cosmetic Ingredient Database (CosIng)
Hydrated Silica
European Commission
EU Cosmetic Ingredient Database (CosIng)
Lithium Magnesium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Lithium Magnesium Sodium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Magnesium Aluminometasilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Magnesium Aluminum Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Magnesium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Magnesium Trisilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Polymethylsilsesquioxane/Trimethylsiloxysilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Potassium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
silica
European Commission
EU Cosmetic Ingredient Database (CosIng)
Silica dimethyl silylate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Silica Silylate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Silver Borosilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Sodium Magnesium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Sodium Metasilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Sodium Potassium Aluminum Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Sodium Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Sodium Silver Aluminum Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Trifluoropropyldimethyl/trimethylsiloxysilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Trimethylsiloxysilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Trimethylsiloxysilicate/Dimethicone Crosspolymer
European Commission
EU Cosmetic Ingredient Database (CosIng)
Trimethylsiloxysilicate/Dimethiconol Crosspolymer
European Commission
EU Cosmetic Ingredient Database (CosIng)
Vinyldimethyl/Trimethylsiloxysilicate Stearyl Dimethicone Crosspolymer
European Commission
EU Cosmetic Ingredient Database (CosIng)
Vinyldimethyl/Trimethylsiloxysilicate/Dimethicone Crosspolymer
European Commission
EU Cosmetic Ingredient Database (CosIng)
Zinc Borosilicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Zinc Silicate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Developing a stable aqueous enteric coating formulation with hydroxypropyl methylcellulose acetate succinate (HPMCAS-MF) and colloidal silicon dioxide
Deshpande TM, Quadir A, Obara S, Ibrahim A, Hoag SW
International journal of pharmaceutics, 2018
Final report on the safety assessment of aluminum silicat...
Amy R Elmore
International journal of toxicology, 2003
Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2003
Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2003
Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2003
Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2003
Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2003
Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2003
Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate,
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2003
Final report on the safety assessment of potassium silicate, sodium metasilicate, and sodium silicate.
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2005
Final report on the safety assessment of potassium silicate, sodium metasilicate, and sodium silicate.
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2005
Final report on the safety assessment of potassium silicate, sodium metasilicate, and sodium silicate.
Elmore AR, Cosmetic Ingredient Review Expert Panel
International journal of toxicology, 2005
Alumina Magnesium Metasilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Aluminum Calcium Sodium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Aluminum Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Calcium Aluminum Borosilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Calcium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Calcium Sodium Borosilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Calcium Titanium Borosilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Dimethicone/Vinyltrimethylsiloxysilicate Crosspolymer
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Hydrated Silica
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Lithium Magnesium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Lithium Magnesium Sodium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Magnesium Aluminum Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Magnesium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Magnesium Trisilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Potassium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Silica dimethyl silylate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Silica Silylate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Sodium Magnesium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Sodium Metasilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Sodium Potassium Aluminum Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Sodium Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Sodium Silver Aluminum Silicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Trifluoropropyldimethyl/trimethylsiloxysilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Trimethylsiloxysilicate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Trimethylsiloxysilicate/Dimethicone Crosspolymer
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Trimethylsiloxysilicate/Dimethiconol Crosspolymer
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Misconceptions regarding the pathogenicity of silicas and silicates.
Feigin DS
Journal of thoracic imaging, 1989
Colloidal hydrogel systems of thymol-loaded PLGA nanoparticles designed for acne treatment.
Folle C, Marqués AM, Mallandrich M, Suñer-Carbó J, Halbaut L et al.
Colloids and surfaces. B, Biointerfaces, 2024
Colloidal oatmeal: history, chemistry and clinical properties.
Kurtz ES, Wallo W
Journal of drugs in dermatology : JDD, 2007
Jojoba Oil Soft Colloidal Nanocarrier of a Synthetic Retinoid: Preparation, Characterization and Clinical Efficacy in Psoriatic Patients.
Nasr M, Abdel-Hamid S, Moftah NH, Fadel M, Alyoussef AA
Current drug delivery, 2017
Studies of prophylaxis pastes containing sodium-potassium aluminum silicate and fluoride.
Putt MS, Kleber CJ, Muhler JC
Journal of dental research, 1979
Antioxidant and Anti-Melanogenesis Effects of Colloidal Gold Camellia sinensis L. Extracts.
Shin S, Kim M, Song N, Sun S, Choi J et al.
Molecules (Basel, Switzerland), 2022
Dermal peptide delivery using enhancer molecules and colloidal carrier systems. Part III: Tetrapeptide GEKG.
Sommer E, Neubert RHH, Mentel M, Tuchscherer B, Mrestani Y et al.
European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences, 2018
The preparation of lactoferrin/magnesium silicate lithium injectable hydrogel and application in promoting wound healing.
Wang B, Zhao J, Lu W, Ma Y, Wang X et al.
International journal of biological macromolecules, 2022
The preparation of lactoferrin/magnesium silicate lithium injectable hydrogel and application in promoting wound healing.
Wang B, Zhao J, Lu W, Ma Y, Wang X et al.
International journal of biological macromolecules, 2022
Composite Aerogel Scaffolds Containing Flexible Silica Nanofiber and Tricalcium Phosphate Enable Skin Regeneration.
Wang X, Yuan Z, Shafiq M, Cai G, Lei Z et al.
ACS applied materials & interfaces, 2024
Spindle-Like Zinc Silicate Nanoparticles Accelerating Innervated and Vascularized Skin Burn Wound Healing.
Zhang H, Ma W, Ma H, Qin C, Chen J et al.
Advanced healthcare materials, 2022
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR