Ammonium Bisulfite
AKA “Ammonium hydrogen sulfite, Ammonium acid sulfite, Ammonium monosulfite, Monoammonium sulfite, Ammonium hydrosulfite, Sulfurous acid, monoammonium salt, Ammonium sulfite
Synthetic
Ingredient Facts
Ammonium bisulfite
AKA: Ammonium hydrogen sulfite, Ammonium acid sulfite, Ammonium monosulfite, Monoammonium sulfite, Ammonium hydrosulfite, Sulfurous acid, Monoammonium salt, Ammonium sulfite
Synthetic · Preservative · EWG: 4
Synthetic
Preservative
Synthetic
Clean
A chemical that helps straighten or wave hair while keeping the product fresh and effective. Works by altering hair structure to create your desired style.
Solubility In water: 267 g/100 ml @ 10 °C, 620 G/100 ml @ 60 °C
Formula
H5NO3S
Mol. Weight
99.11
CAS #
10192-30-0
Form
Powder
State
Ammonium bisulfite is colorless crystals which are soluble in water. It is noncombustible. It is corrosive to aluminum. It is a strong irritant to skin and mucous membranes. It is toxic by skin absorp
See origin →
Functions
Hair Waving Or Straightening
Preservative
Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.
Reducing
Preserves Formula
Reducing Agent
Antioxidant Protection
Fights Bacteria
Reduces Inflammation
Changes hair texture
Prevents microbial growth
Chemical reduction
Traditional Use
Developed as a preservative and antioxidant in the 19th century for use in food and cosmetics. Used to prevent oxidation and microbial growth in cosmetic formulations.
Skin Types
all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Caution
EWG
4
CIR
Safe w/Qualifications
Pregnancy
Caution
CIR Safety Findings
Not an Irritant
medical-approval
all-shades-safe
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 Status
USApermitted
EUpermitted
JAPANpermitted
CANADApermitted
Verified Feb 2026
Data: PubChem · CosIng · EWG · CIR