What does Formamidine sulfinic acid do?

Used in cosmetics as a reducing agent.

Is Formamidine sulfinic acid safe?

We haven't assessed a concern score for this ingredient yet. It is listed for cosmetic use in the EU.

beauty
industrial

Formamidine sulfinic acid

CAS 23056-93-1

Also registered as 6 other CAS numbers

42580-06-3 · 56766-73-5 · 110445-04-0 · 852937-99-6 · 1081537-75-8 · 1758-73-2

Formamidine sulfinic acid chemical structure

Concern score

Not assessed — no hazard data yet.

Formamidine sulfinic acid in plain language

What it is: Also known as Amino(imino)methanesulfinic acid · Thiourea dioxide · Formamidinesulfinic acid · Methanesulfinic acid, aminoimino- · Aimsa · Acide aminoiminomethanesulfinique
Show all 19 names
Aminoiminomethanesulfinic acid · Aminoiminomethansulfinsaure · CH4N2O2S · Degussa F · Formamidine sulfinate · Formamidinesulphinic acid · Manofast · Methanesulfinic acid, 1-amino-1-imino- · Methenesulfinic acid, aminoimino- · acido aminoiminometanosulfinico · aminoiminomethanesulphinic acid · carbamimidoylsulfinic acid · formamidine sulfuric acid
What it does: Used in cosmetics as a reducing agent.
Reducing
Is it a concern?: We haven't assessed a concern score for this ingredient yet. It is listed for cosmetic use in the EU.

Regulation

No restrictions found. Formamidine sulfinic acid appears in these published regulatory listings.

Recorded in these product areas

Found in consumer products
Industrial

EUCosIngActiveFormamidine Sulfinic Acid is the organic compound
- Formamidine Sulfinic Acid is the organic compoundSource →
USEPAcommercial use observedEPA CPDat observed this chemical in 0 composition records across product categories including unclassified products. EPA CPDat classifies this chemical for functional uses including Reducing agent.
- EPA CPDat observed this chemical in 0 composition records across product categories including unclassified products. EPA CPDat classifies this chemical for functional uses including Reducing agent.Source →
USFDAlisted in openFDA substanceopenFDA substance registry classifies this ingredient as chemical.
- openFDA substance registry classifies this ingredient as chemical.Source →

Expert safety opinions

No expert opinion on file for Formamidine sulfinic acid. These are the independent scientific bodies that assess ingredients like this one; we show an opinion only when a record we hold cites it.

SCCS
EU Scientific Committee on Consumer Safety
No SCCS opinion on file.
CIR
Cosmetic Ingredient Review (US expert panel)
No CIR safety assessment on file.

Evidence & sources

No graded research studies for Formamidine sulfinic acid yet. This record is compiled from the published data sources below — registries and regulatory listings, not study findings.

6 data sources

Where this comes from

CosIng
regulatory · updated 2026-09-23
Open →
EPA Chemical and Products Database
exposure · updated 2019-12-20
Open →
EPA DSSTox Identifiers
chemistry · updated 2025-12-29
Open →
FDA GSRS UNII
registry · updated 2026-02-26
Open →
openFDA Substance
registry · updated 2026-05-24
Open →
PubChem Live Enrichment
chemistry · updated 2026-05-17
Open →

Suitability

Context-specific fit derived from published classifications and the current ingredient evidence profile.

Fragrance avoidance

Nothing to weigh for this context yet.

No signal in this context

We have no published hazard signal for this ingredient, so we cannot say how it behaves in this context — that is missing evidence, not a clean result.

Where it has been recorded

How often EPA CPDat has listed Formamidine sulfinic acid in a product composition. These are source records, not Greenveil catalog products.

Named organisations

Typical roles

Reducing

See products using Formamidine sulfinic acid →