Guanine

Also known as: EINECS 200-799-8, UNII-5Z93L87A1R, 2-Amino-1,9-dihydro-6H-purin-6-one, 2-Amino-1,9-dihydro-purin-6-one, 2-Amino-3,7-dihydro-6H-purin-6-one (+12 more)

INCI: GUANINE

Guanine (CAS 73-40-5) is a cosmetic cosmetic ingredient functioning as Opacifying agent; colorant (pearlescent/iridescent effect). EU Regulation 1223/2009 status: permitted. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.

View industrial chemical safety profile for CAS 73-40-5 →

Auto-generated CPSR Part A draft with source citations
Function
Opacifying agent; colorant (pearlescent/iridescent effect)
Safety Rating
EXCELLENT

Chemistry & Identifiers

Formula
C5H5N5O
MW
151.13 g/mol
EC Number
200-799-8
PubChem CID
135398634
IUPAC Name
2-amino-1,7-dihydropurin-6-one
InChIKey
UYTPUPDQBNUYGX-UHFFFAOYSA-N

Regulatory Status

EU EU Status permitted
US US Status permitted
US Notes Permitted — permanently listed, exempt from certification; approved for cosmetics generally including eye area under 21 CFR 73.2329

For full compliance data across multiple jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety, dermal absorption, and sensitization profile summaries for Guanine.

Calculate MoS for your specific formulation with the MoS Calculator.

ECHA REACH Registration

European Chemicals Agency REACH dossier and Substances of Very High Concern listing.

Registration Type
Intermediate
Tonnage Band
Intermediate use only
Substance Type
SUBSTANCE
SVHC Candidate
No

EU CosIng Annex Listing

European Commission CosIng database Annex references per Regulation (EC) No 1223/2009.

Annex IV — Permitted Colorants
Product type: White

Expanded Jurisdictional Detail

Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.

SA Saudi SFDA (IV - Colorants)
BRIN Brazil/India Cosmetics
India: Permitted Colorant
Additional Jurisdictional Restrictions (1)
Jurisdiction Status Max % Product Type
ASEAN permitted_colorant - All products

Additional Ingredient Properties

1 property record from structured ingredient metadata.

colorant_formulator
{"ci_number": "77439", "ci_name": "Natural Pearl", "color_category": "white", "color_hex_code": "#F8F8FF", "natural_or_synthetic": "natural", "organic_or_inorganic": "organic", "lake_or_dye": "pigment", "fda_approved_use": "eye/general", "eu_approved_cosmetic": "yes", "japan_approved": "yes", "china_approved": "yes", "coverage_opacity": "transparent", "tinting_strength": "low", "lightfastness_rati…

Function Categories & List Membership

Cosmetic/Chemical Function Categories
Dye Opacifer
Regulatory List Membership (2)
EU Regulated in Personal Care EU CosIng Cosmetics Ingredient Database

Expert Verdict

Expert safety assessment and concern-level summary for Guanine.

Regulatory Flags

potential-allergen colorant eu_cosing_listed

Known Synonyms

EINECS 200-799-8 UNII-5Z93L87A1R 2-Amino-1,9-dihydro-6H-purin-6-one 2-Amino-1,9-dihydro-purin-6-one 2-Amino-3,7-dihydro-6H-purin-6-one 2-Amino-6-purinol 2-Amino-Hypoxanthine 2-amino-6,7-dihydro-3H-purin-6-one 2-amino-6-oxopurine 6-Hydroxy-2-aminopurine CI Natural white 1 GUN Gua Guanin Mearlmaid Naturon Pathocidin

Chemical Function

Dye Opacifer

Regulatory Lists

Europe; Personal care pharmaceutical Personal care Canada; pharmaceutical

Cross-Vertical Safety Context

Same-CAS public records found in pharmaceutical data.

SOURCE ChEMBL / DrugCentral / FAERS DB_PHARMA CAS match

Pharmaceutical Data

Same-CAS rows from the pharmaceutical spoke database.

Compound
GUANINE
ChEMBL ID
CHEMBL219568
Max Phase
3
View full pharmaceutical profile →

Frequently Asked Questions

Is Guanine safe in cosmetics?

Guanine has a safety rating of "EXCELLENT" in our database. EU status: permitted. US status: permitted.

Is Guanine allowed in the EU?

Guanine EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.

What does Guanine do in cosmetics?

Guanine functions as: Opacifying agent; colorant (pearlescent/iridescent effect). It is classified as a cosmetic ingredient in our database. CAS number: 73-40-5.

Is Guanine used outside cosmetics?

Guanine also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.

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