FERROUS AMMONIUM SULFATE

About FERROUS AMMONIUM SULFATE

An iron(II) ammonium sulfate double salt used as an antimicrobial agent in cosmetic formulations, with EU restriction related to metal compound classification and environmental concerns about aquatic toxicity.

Detailed Analysis

Ferrous Ammonium Sulfate (CAS 10045-89-3, PubChem CID 24863) is an iron(II) double salt with ammonium sulfate (Mohr's salt) used for its antimicrobial properties in cosmetic formulations. The EU CosIng restriction 'ban substances that deplete the ozone layer' is likely a generic database flag for metal compound submissions rather than a specific concern for this compound. Ferrous iron can participate in Fenton-type reactions generating reactive oxygen species, which is the primary safety concern, particularly in leave-on products where cumulative iron exposure could occur. However, at antimicrobial use levels, systemic absorption of iron is minimal. Iron salts are generally well-tolerated topically, though they can cause temporary discoloration.

What It Does

Skin Benefits

• ✓ Antimicrobial/preservative activity
• ✓ Mild astringent effect

Known Concerns

• ⚠ Ferrous iron — Fenton reaction potential generates ROS at high concentrations
• ⚠ Metal compound classification in EU triggers generic restriction flag
• ⚠ Can cause temporary skin discoloration (brown iron staining)

References