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ProhibitedBinding ruleGBOriginal is EnglishOfficial-source import checked

Leucomalachite green;N,N,N′,N′-tetramethyl-4,4′-benzylidenedianiline

The consolidated GB Cosmetics Regulation lists this record in Annex II.

All Great Britain recordsCompare all marketsOpen official source

Regulatory decision and full conditions

Status
Prohibited
Legal role
Binding rule
Regulatory summary
The consolidated GB Cosmetics Regulation lists this record in Annex II.
Conditions and restrictions
A prohibition entry may contain no separate condition text because the regulatory outcome is the prohibition itself. Open the cited source and apply the market-wide requirements below.

Substance identity

Official source name
Leucomalachite green;N,N,N′,N′-tetramethyl-4,4′-benzylidenedianiline
CAS
129-73-7
EC
204-961-9
Identity mapping
standalone:official_gb_annex
Search this identity across the siteCAS 129-73-7EC 204-961-9

Cross-market snapshot for this identity

Exact linked records currently present in this site. An absent market means no imported exact match, not permission to use the substance.

6 market datasets
PubChem 2D chemical structure for CAS 129-73-7
CAS 129-73-7PubChem CID 67215

Verified chemistry for CAS 129-73-7

Leucomalachite green

IUPAC name
4-[[4-(dimethylamino)phenyl]-phenylmethyl]-N,N-dimethylaniline
Molecular formula
C23H26N2
Molecular weight
330.5 g/mol
Exact mass
330.209598838 Da
Monoisotopic mass
330.209598838 Da
XLogP3
5.3
Topological polar surface area
6.5 Ų
Molecular complexity
342.0
Formal charge
0
Hydrogen-bond donors
0
Hydrogen-bond acceptors
2
Rotatable bonds
5
Heavy atoms
25
Covalent units
1

Names and synonyms reported to PubChem

Malachite green leucoMalachite green leuco base4,4'-Bis(dimethylamino)triphenylmethaneC.I. Basic Green 4, leuco baseTetramethyldiaminotriphenylmethaneBis(p-dimethylaminophenyl)phenylmethanep,p'-Benzylidenebis(N,N-dimethylaniline)4,4'-Benzylidene bis(N,N-dimethylaniline)
16 more reported names
Aniline, 4,4'-benzylidenebis(N,N-dimethyl-Bis(p-(N,N-dimethylamino)phenyl)phenylmethane4,4'-Bis(N,N-dimethylaminophenyl)phenylmethaneBenzenamine, 4,4'-(phenylmethylene)bis[N,N-dimethyl-Bis(4,4'-(dimethylamino)phenyl)phenyl methane4,4'-(Phenylmethylene)bis(N,N-dimethylbenzenamine)4,4'-benzylidenebis(N,N-dimethylaniline)NSC-363798U61G37Z20Benzenamine, 4,4'-(phenylmethylene)bis(N,N-dimethyl-Bis[p-(N,N-dimethylamino)phenyl]phenylmethaneBis[4,4'-(dimethylamino)phenyl]phenyl methaneRefChem:153083204-961-9Leuco malachite greenLeucoMalachiteGreen
Open full PubChem recordSafety and hazards at PubChemPubChem annotationsChemical classifications3D structure image
External database identifiers
Advanced structure statistics
Defined atom stereocentres
0
Undefined atom stereocentres
0
Defined bond stereocentres
0
Undefined bond stereocentres
0
3D pharmacophore features
5
3D rings
3
3D hydrophobes
0
3D acceptor features
0
3D donor features
0
3D anionic centres
0
3D cationic centres
2
3D conformers
4
Effective 3D rotors
5.0
Machine-readable structure identifiers
SMILES
CN(C)C1=CC=C(C=C1)C(C2=CC=CC=C2)C3=CC=C(C=C3)N(C)C
InChI
InChI=1S/C23H26N2/c1-24(2)21-14-10-19(11-15-21)23(18-8-6-5-7-9-18)20-12-16-22(17-13-20)25(3)4/h5-17,23H,1-4H3
InChIKey
WZKXBGJNNCGHIC-UHFFFAOYSA-N

Evidence from additional scientific databases

NIH PubChem PUG-View
Exact identifier match67215

Attributed physical-property, hazard, environmental and use annotations.

  • Signal: Warning Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • GHS Hazard Statements: H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]; H351: Suspected of causing cancer [Warning Carcinogenicity] Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • Precautionary Statement Codes: P203, P280, P318, P405, and P501 (click each P-code to see the statement) Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • Signal: Danger Source: European Chemicals Agency (ECHA)
  • GHS Hazard Statements: H302 (96.2%): Harmful if swallowed [Warning Acute toxicity, oral]; H311 (15.4%): Toxic in contact with skin [Danger Acute toxicity, dermal]; H315 (15.4%): Causes skin irritation [Warning Skin corrosion/irritation]; H331 (15.4%): Toxic if inhaled [Danger Acute toxicity, inhalation]; H332 (15.4%): Harmful if inhaled [Warning Acute toxicity, inhalation]; H400 (96.2%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard] Source: European Chemicals Agency (ECHA)
  • Precautionary Statement Codes: P261, P262, P264, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P316, P317, P321, P330, P332+P317, P361+P364, P362+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement) Source: European Chemicals Agency (ECHA)
  • ECHA C&L Notifications Summary: Aggregated GHS information provided per 52 reports by companies from 6 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.; Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. Source: European Chemicals Agency (ECHA)
  • Signal: Danger Source: NITE-CMC
  • GHS Hazard Statements: H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]; H351: Suspected of causing cancer [Warning Carcinogenicity]; H361: Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]; H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]; H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure] Source: NITE-CMC
  • Precautionary Statement Codes: P203, P260, P264, P270, P280, P318, P319, P405, and P501 (click each P-code to see the statement) Source: NITE-CMC
  • Signal: Warning Source: Hazardous Chemical Information System (HCIS), Safe Work Australia
  • GHS Hazard Statements: H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]; H351: Suspected of causing cancer [Warning Carcinogenicity] Source: Hazardous Chemical Information System (HCIS), Safe Work Australia
  • Environmental Bioconcentration: An estimated BCF of 2800 was calculated in fish for leucomalachite green(SRC), using an estimated log Kow of 5.72(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is very high(SRC), provided the compound is not metabolized by the organism(SRC). Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 9.8X10+4(SRC), determined from a structure estimation method(2), indicates that leucomalachite green is expected to be immobile in soil(SRC). The estimated pKa of leucomalachite green is 5.46(3), indicating that this compound will exist partially in the cation form in the environment and cations generally adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Volatilization of the neutral species from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 9.8X10-9 atm-cu m/mole(SRC), using a fragment constant estimation method(5). Leucomalachite green is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 1.9X10-7 mm Hg at 25 °C(SRC), determined from a fragment constant method(6). Biodegradation data in soil were not available(SRC, 2012). Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 9.8X10+4(SRC), determined from a structure estimation method(2), indicates that leucomalachite green is expected to adsorb to suspended solids and sediment(SRC). Volatilization of the neutral species from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 9.8X10-9 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). The estimated pKa of 5.72(5) indicates leucomalachite green will exist partially in the cation form at pH values of 5 to 9 and, therefore, volatilization from water surfaces is not expected to be an important fate process(SRC). According to a classification scheme(6), an estimated BCF of 2800(SRC), from an estimated log Kow of 5.72(7) and a regression-derived equation(8), suggests the potential for bioconcentration in aquatic organisms is very high, provided the compound is not metabolized by the organism(SRC). Biodegradation data in water were not available(SRC, 2012). Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), leucomalachite green, which has an estimated vapor pressure of 1.9X10-7 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase leucomalachite green is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 0.6 hours(SRC), calculated from its rate constant of 2.1X10-10 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase leucomalachite green may be removed from the air by wet or dry deposition(SRC). Leucomalachite green contains chromophores that absorb at wavelengths >290 nm(4) and, therefore, may be susceptible to direct photolysis by sunlight(SRC). Source: Hazardous Substances Data Bank (HSDB)

Mapped by: Existing checksum-valid CAS to unique PubChem CID match. Retrieved: 2026-08-31. Open source record

Scientific classifications and hazard annotations provide context and do not replace the market-specific regulatory decision shown above.

Additional source coverage and match status
SourceResultChecked
NIH PubChem PUG-ViewExact match2026-08-31

A recorded no-match is useful evidence that the source was checked; it is not a claim that the substance does not exist elsewhere.

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Official source and provenance

Registered source
Great Britain Cosmetics Regulation — consolidated Annexes II–VI and amendments
Source reference
GB Cosmetics Regulation, Annex II, entry 1550
Source record ID
II-1550
Source version
2026-08-15
Source language
English
Translation status
Original is English
Effective date
2026-08-15
Source updated
2026-08-19
Snapshot checked
2026-08-30 04:51 UTC
Validation method
legislation.gov.uk XML table parse; {'II': 1758, 'III': 326, 'IV': 154, 'V': 57, 'VI': 34}
SHA-256
e3a386d950f54c6e7a7f9e784d1bd46e52de725137e89d5630709824475215d8

Registered dataset notes

Dataset coverage
Complete consolidated GB Annexes II–VI, with later amendments versioned separately
Authority note
Binding GB schedules and versioned amendments to retained Regulation 1223/2009; applies to England, Wales and Scotland, not Northern Ireland
Source licence
Open Government Licence v3.0 / Crown copyright
Attribution
Contains public sector information licensed under the Open Government Licence v3.0.
Inspect the exact official sourceRegulator guidance

How this record fits the market dataset

2329
current Great Britain records
1758
records marked Prohibited
2329
records from this source version
2015
market records with CAS identity

Status distribution

Permitted list with conditions: 245Prohibited: 1758Restricted: 326

Condition text is present on 517 of 2329 current records. An empty condition field is interpreted according to the record type above; it is never converted into an unrestricted-use claim.

Great Britain market context

Complete consolidated annex dataset

Coverage version: GB retained Regulation 1223/2009 schedules, effective 15 August 2026

Current consolidated Annexes II–VI for England, Scotland and Wales.

Verification checklist

  1. Confirm INCI/CAS/EC identity.
  2. Review every current GB Annex II–VI match.
  3. Check commencement dates and later statutory instruments.
  4. Verify SCPN, responsible-person, safety-report and labelling duties.

Official market sources

Verification workflow and record completeness

Before using this result in a compliance decision

  1. Confirm that “Leucomalachite green;N,N,N′,N′-tetramethyl-4,4′-benzylidenedianiline” and every CAS/EC identifier refer to the material in your supplier specification.
  2. Confirm INCI/CAS/EC identity.
  3. Review every current GB Annex II–VI match.
  4. Check commencement dates and later statutory instruments.
  5. Verify SCPN, responsible-person, safety-report and labelling duties.
  6. Document the source version and recheck the regulator before manufacture, notification or market placement.

Fields available in this record

  • Official substance nameAvailable
  • CASAvailable
  • ECAvailable
  • Separate condition textNot present in source row
  • Effective dateAvailable
  • Snapshot hash and methodAvailable

Questions this page answers

This official record identifies the substance as prohibited for cosmetic use in the stated market scope. Do not rely on a formulation containing this identity until the cited source, effective date and exact substance match have been verified.

A prohibition entry may contain no separate condition text because the regulatory outcome is the prohibition itself. No annex match is not approval and does not cover Northern Ireland, which follows the applicable EU framework.

The record cites GB Cosmetics Regulation, Annex II, entry 1550, source version 2026-08-15. Open the official source.

No. CAS helps resolve identity, but jurisdictions can classify the same substance differently and can apply different product scopes, limits, warnings and transition dates.

Stable citation

Leucomalachite green;N,N,N′,N′-tetramethyl-4,4′-benzylidenedianiline. GB Cosmetics Regulation, Annex II, entry 1550. Great Britain. Source version 2026-08-15. CosIng Checker regulatory record: https://cosingchecker.com/regulations/gb/records/5905/

Cite the regulator as the legal authority. This page is a structured evidence index and verification aid, not a substitute for the official text or professional legal assessment.

Interpretation and limits for Great Britain

This official record identifies the substance as prohibited for cosmetic use in the stated market scope.

Do not rely on a formulation containing this identity until the cited source, effective date and exact substance match have been verified.

How to interpret the legal role

The cited row forms part of a binding rule or legally incorporated list for this market.

Evidence on this page

  • Recorded outcome: Prohibited
  • Legal role: Binding rule
  • Source version: 2026-08-15
  • Effective date: 2026-08-15

What it does not prove

No annex match is not approval and does not cover Northern Ireland, which follows the applicable EU framework.

Further authoritative substance research

These sources can add identity, safety, exposure or hazard context. A link is not evidence that the database contains this exact substance, and none of these sources overrides the market decision above.

Cosmetic Ingredient Review safety assessments

Expert Panel conclusions, assessed ingredient groups, use conditions, dates and report documents

Independent expert review considered by FDA; not a government approval or binding market rule

Research this identity at the source

FDA Global Substance Registration System

UNII identifiers, preferred names, substance types, codes and public substance relationships

Identity registry only; UNII availability does not imply FDA review or approval

Research this identity at the source

ILO/WHO International Chemical Safety Cards

Hazards, symptoms, first aid, storage, incompatibilities and physical properties for covered chemicals

International occupational chemical-safety reference; not cosmetic-use approval

Research this identity at the source

Japan NITE-CHRIP

Chemical identity, Japanese and foreign legal lists, GHS hazards and exposure-related information

Chemical-management evidence; cosmetic status remains governed by the applicable MHLW standard and market rules

Research this identity at the source

NIOSH Pocket Guide to Chemical Hazards

REL, PEL, IDLH, properties, exposure routes, symptoms, target organs, first aid and measurement methods for covered workplace chemicals

US occupational-health guidance and limits; not a cosmetic ingredient decision

Research this identity at the source

OECD eChemPortal

Gateway to authority-owned physical-property, fate, ecotoxicity, toxicity, exposure and GHS records

Discovery gateway; each linked authority remains responsible for its data

Research this identity at the source

US EPA CompTox CTX APIs

API key required for import

DTXSID identity, experimental and predicted properties, toxicity, bioactivity, exposure and environmental data

Scientific and computational evidence; predictions must remain labelled and do not determine cosmetic legality

Research this identity at the source