Sodium Metabisulfite
AKA “Sodium pyrosulfite, Sodium disulfite, Disodium pyrosulfite, Natrii disulfis, Campden Tablets, Disodium metabisulfite, Natrium pyrosulfit, Natriummetabisulfit”
Synthetic
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Ingredient Facts
Sodium metabisulfite
AKA: Sodium pyrosulfite, Sodium disulfite, Disodium pyrosulfite, Natrii disulfis, Campden Tablets, Disodium metabisulfite, Natrium pyrosulfit, Natriummetabisulfit
Synthetic · Antioxidant · EWG: 4
Plant-Derived
Antioxidant
Preservative
Medicated Active
Synthetic
Clean
A preservative that keeps products fresh and stable by protecting against oxidation. Helps extend shelf life so your beauty products stay effective longer.
Solubility 54 % (NIOSH, 2024)
Formula
Na2O5S2
Mol. Weight
190.11
CAS #
7681-57-4, 7757-74-6
Form
Powder
Plant-Derived
Synthetic. Produced from sulfur dioxide and sodium carbonate through chemical synthesis. Created by combining these precursor chemicals under controlled industrial conditions.
Functions
Antioxidant
Preservative
Reducing
Benefits
Neutralizes Free Radicals
Traditional Use
Developed in the 19th century as a preservative and antioxidant, first used industrially before being adopted in cosmetics in the mid-20th century to prevent oxidation and microbial growth in skincare products.
Skin Types
all-skin-types
Best For
Target
General
Melanin-Rich Skin
Suitable
Pregnancy Safe
Caution
EWG Score4
CIR Safety Findings
medical-approval, all-shades-safe, Not an Irritant
Concentration Guide
0.2%
0%0%
Reg. Limit
EU regulatory limit: 0.2%. SO2) Source: EU Cosmetics Regulation (EC) 1223/2009, Annex V (Preservatives), Entry 9.
Regulatory Agencies
Verified Feb 2026
Data: PubChem · CosIng · EWG · CIR