Skip to main content
Annex II Entry 709 CMR23/11/2016

3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts

3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts is listed in Annex II as a prohibited substance for cosmetic products placed on the EU market.

Prohibited substance— Annex II, EU Regulation 1223/2009
Entry: 709
CMR

Chemical identity and properties

PubChem 2D chemical structure for CAS 119-90-4
CAS 119-90-4PubChem CID 8411

Dianisidine

3,3'-dimethoxybenzidine appears as colorless crystals or a light brown powder. Turns violet on standing. Carcinogen. CAMEO Chemicals

IUPAC name
4-(4-amino-3-methoxyphenyl)-2-methoxyaniline
Molecular formula
C14H16N2O2
Molecular weight
244.29 g/mol
Exact mass
244.121177757 Da
XLogP3
2.2
Topological polar surface area
70.5 Ų
Hydrogen-bond donors
2
Hydrogen-bond acceptors
4
Covalent units
1
Defined stereocentres
0

Also known as

o-Dianisidine3,3'-DIMETHOXYBENZIDINEBlue Base NBFast Blue B BaseCellitazol BMitsui Blue B Baseortho-DianisidineAzogene Fast Blue B
16 more reported names
Diacel Navy DCNeutrosel navy bnDisperse Black 6Blue BN BaseBlue Base irga BSpectrolene Blue BFast Blue Base BLake Blue B Baseo-DianisidinaDiato Blue Base BDiazo Fast Blue Bo-DianisidinAzofix Blue B SaltKayaku Blue B BaseFast Blue DSC BaseSetacyl Diazo Navy R
External database identifiers

Evidence from additional scientific databases

NIH PubChem PUG-View
Exact identifier match8411

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

  • First Aid: EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.; SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas.; INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknow Source: CAMEO Chemicals
  • First Aid: (General first aid procedures); Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.; Skin: Soap wash immediately - If this chemical contacts the skin, immediately wash the contaminated skin with soap and water. If this chemical penetrates the clothing, immediately remove the clothing, wash the skin with soap and water, and get medical attention promptly.; Breathing: Respiratory support; Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately. Source: The National Institute for Occupational Safety and Health (NIOSH)
  • Signal: Danger Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • GHS Hazard Statements: H302: Harmful if swallowed [Warning Acute toxicity, oral]; H350: May cause cancer [Danger Carcinogenicity] Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • Precautionary Statement Codes: P203, P264, P270, P280, P301+P317, P318, P330, 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 (100%): Harmful if swallowed [Warning Acute toxicity, oral]; H350 (100%): May cause cancer [Danger Carcinogenicity] Source: European Chemicals Agency (ECHA)
  • Precautionary Statement Codes: P203, P264, P270, P280, P301+P317, P318, P330, 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 50 reports by companies from 5 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: H302: Harmful if swallowed [Warning Acute toxicity, oral]; H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]; H350: May cause cancer [Danger Carcinogenicity]; H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure] Source: NITE-CMC
  • Precautionary Statement Codes: P203, P260, P264, P270, P280, P301+P317, P318, P319, P330, P405, and P501 (click each P-code to see the statement) Source: NITE-CMC
  • Signal: Warning Source: NITE-CMC
  • GHS Hazard Statements: H302: Harmful if swallowed [Warning Acute toxicity, oral]; H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]; H351: Suspected of causing cancer [Warning Carcinogenicity]; H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure] Source: NITE-CMC
  • NFPA Health Rating: 0 - Materials that, under emergency conditions, would offer no hazard beyond that of ordinary combustible materials. Source: Hazardous Substances Data Bank (HSDB)
  • NFPA Fire Rating: 1 - Materials that must be preheated before ignition can occur. Materials require considerable preheating, under all ambient temperature conditions, before ignition and combustion can occur. Source: Hazardous Substances Data Bank (HSDB)
  • NFPA Instability Rating: 0 - Materials that in themselves are normally stable, even under fire conditions. Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Bioconcentration: An estimated BCF of 5 was calculated for 3,3'-dimethoxybenzidine(SRC), using a log Kow of 1.81(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC). Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 230(SRC), determined from a log Kow of 1.81(2) and a regression-derived equation(3), indicates that 3,3'-dimethoxybenzidine is expected to have moderate mobility in soil(SRC). The first pKa of 3,3'-dimethoxybenzidine is estimated as 4.2(SRC), using an estimation method based on perturbed molecular orbital theory and linear free energy (LFER) methods(4). This estimated pKa indicates that 3,3'-dimethoxybenzidine will partially exist in the protonated form under acidic conditions and cations have greater adsorption to soils than neutral molecules(SRC). Furthermore, 3,3'-dimethoxybenzidine is an aromatic amine which may form covalent bonds with humic materials resulting in relatively immobile quinone-like complexes(5). Volatilization of the neutral species of 3,3'-dimethoxybenzidine from moist soil surfaces is not expected to be an important fate process(SRC) based upon an estimated Henry's Law constant of 4.7X10-11 atm-cu m/mole(SRC), developed using a fragment constant estimation method(6). The conjugate acid of 3,3-dimethoxybenzidine will not volatilize since cations are non-volatile(SRC). 3,3'-Dimethox Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 230(SRC), determined from a log Kow of 1.81(2) and a regression-derived equation(3), indicates that 3,3'-dimethoxybenzidine is expected to adsorb to suspended solids and sediment(SRC). The frist pKa of 3,3'-dimethoxybenzidine is estimated as 4.2(SRC), using an estimation method based on perturbed molecular orbital theory and linear free energy (LFER) methods(4). This estimated pKa indicates that 3,3'-dimethoxybenzidine will partially exist in the protonated form under acidic conditions and cations have greater adsorption to suspended solids and sediment than neutral molecules(SRC). Volatilization of the free base from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 4.7X10-11 atm-cu m/mole(SRC), developed using a fragment constant estimation method(5). The conjugate acid of 3,3'-dimethoxybenzidine will not volatilize since cations are non-volatile(SRC). According to a classification scheme(6), an estimated BCF of 5(SRC), from its log Kow(2) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). No information on t 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), 3,3'-dimethoxybenzidine, which has an estimated vapor pressure of 1.2X10-7 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase 3,3'-dimethoxybenzidine 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 3 hours(SRC), calculated from its rate constant of 1.3X10-10 cu cm/molecule-sec at 25 °C (SRC)determined using a structure estimation method(3). Since 3,3'-dimethoxybenzidine absorbs light greater than 290 nm(4), it may be susceptible to direct photolysis in the environment(SRC). Particulate-phase 3,3'-dimethoxybenzidine may be removed from the air by wet and dry deposition(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 2026-09-02 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Record details

Chemical name

3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts

Chemical / IUPAC name

ortho-Dianisidine

Regulatory information

Key data

Annex
Entry number
709

Direct matches are limited for this record, so nearby entries from Annex II are shown as well.

Annex II 708
Nearby record in the same annex

o-Anisidine

CAS: 90-04-0
EC: 201-963-1

What Annex II means for 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts

3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts is listed as a prohibited substance under Annex II of EU Cosmetics Regulation 1223/2009 and must not be intentionally added. Article 17 separately addresses unintended small quantities that are technically unavoidable under good manufacturing practice and compatible with the Article 3 safety requirement.

Formulators must screen their ingredients and raw materials to ensure none contain this substance. Suppliers should provide documentation confirming absence when requested.

The page also surfaces 12 related annex records with overlapping identifiers, annex logic or naming patterns.

Compliance checklist

  • Verify this substance is absent from all raw materials and finished formulations.
  • Request absence confirmation or CoA from raw material suppliers.
  • Document the screening result in the Product Information File (PIF).
  • This substance has CMR classification. Review the CMR table above and verify current Annex II/III status before use.

Frequently asked questions

Yes. 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts is listed in Annex II of EU Cosmetics Regulation 1223/2009 and is prohibited as an intentionally added cosmetic ingredient. Article 17 provides a narrow exception for unintended small quantities that are technically unavoidable under good manufacturing practice, provided the product remains safe under Article 3.

CAS 119-90-4 is the unique numerical identifier assigned to 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts by the Chemical Abstracts Service. In cosmetic compliance work, the CAS number is used to cross-reference the substance across regulatory databases, raw material specifications and safety assessment reports. Multiple EU annex entries may share the same CAS number if the same substance appears under different conditions or in different annexes.

3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts has a CMR (carcinogenic, mutagenic or reprotoxic) classification under EU CLP Regulation. Under Article 15 of EU Cosmetics Regulation 1223/2009, CMR substances of category 1A or 1B are prohibited in cosmetics unless specifically permitted. Category 2 CMR substances may be used only if assessed safe by the SCCS. Always verify current annex status and any applicable derogations before use.

Use the INCI Checker tool on this site to paste your full ingredient list (INCI) and scan it against all Annex II–VI entries. The tool highlights any ingredients that match restricted, prohibited or allergen-flagged records. This is useful for rapid compliance screening of finished product formulas or raw material declarations.

Source note for Annex II record 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts

This page summarizes one Annex II record for 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts from public European Commission cosmetic materials and adds linked inventory or identifier matches when available.

Use this record page to review Annex II conditions for 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts, but confirm any final regulatory decision against the current official annex wording and source files.

Tools & next steps

Check your formula

Paste a full INCI list to detect 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts and other flagged EU annex records in one pass.

INCI Checker

Compare entries

Compare 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts side by side with another annex record to review differences in restrictions, concentrations and annex placement.

Compare

Browse the annex

See all records in Annex II and compare regulatory conditions across substances in this annex.

Open Annex II