Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

3,3'-dimethoxybenzidine

3,3'-dimethoxybenzidine is leaflets or needles from water.

CAS 119-90-4 C14H16N2O2 244.29 g/mol Danger

01 · Identification

What 3,3'-dimethoxybenzidine is

3,3'-dimethoxybenzidine is leaflets or needles from water. Its molecular formula is C14H16N2O2 and its molecular weight is 244.29 g/mol. It melts at 137 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

02 · Identifiers

3,3'-dimethoxybenzidine identifiers and molecular data

3,3'-dimethoxybenzidine CAS number and EC number

CAS number119-90-4
EC number204-355-4
Index number (CLP Annex VI)612-036-00-X

3,3'-dimethoxybenzidine molecular formula and molecular weight

Molecular formulaC14H16N2O2
Molecular weight244.29 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for 3,3'-dimethoxybenzidine

  • o-dianisidine

03 · GHS classification

3,3'-dimethoxybenzidine hazard classification

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

3,3'-dimethoxybenzidine pictograms and signal word

Signal wordDanger

3,3'-dimethoxybenzidine hazard class and category

GHS hazard classes 3,3'-dimethoxybenzidine falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Carcinogenicity GHS chapter 3.6 Category 1A or 1B H350 GHS08

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

3,3'-dimethoxybenzidine hazard statements (H-codes)

Hazard statements assigned to 3,3'-dimethoxybenzidine
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H302 Harmful if swallowed.

This page lists only the codes assigned to 3,3'-dimethoxybenzidine. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for 3,3'-dimethoxybenzidine

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of 3,3'-dimethoxybenzidin… issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

3,3'-dimethoxybenzidine precautionary statements

CLP Annex VI assigns 8 precautionary statements to 3,3'-dimethoxybenzidine. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

3,3'-dimethoxybenzidine name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български 3,3′-диметоксибензидин o -дианизидин
Spanish español 3,3'-Dimetoxibencidina o -dianisidina
Czech čeština 3,3'-dimethoxybenzidin o -dianisidin
Danish dansk 3,3'-dimethoxybenzidin o -dianisidin
German Deutsch 3,3'-Dimethoxybenzidin o -Dianisidin
Estonian eesti 3,3'-dimetoksübensidiin o -dianisidiin
Greek ελληνικά 3,3′-διμεθοξυβενζιδίνη o -διανισιδίνη
English English 3,3'-dimethoxybenzidine o -dianisidine
French français 3,3'-diméthoxybenzidine o -dianisidine
Croatian hrvatski 3,3'-dimetoksibenzidin o -dianisidin
Italian italiano 3,3'-dimetossibenzidina o -dianisidina
Latvian latviešu 3,3'-dimetoksibenzidīns o -dianizidīns
Lithuanian lietuvių 3,3'-dimetoksibenzidinas o -dianizidinas
Hungarian magyar 3,3’-dimetoxibenzidin o -dianizidin
Maltese Malti 3,3'-dimetossibenżidin o -dianisidina
Dutch Nederlands 3,3'-dimethoxybenzidine o -dianisidine
Polish polski 3,3'-dimetoksybenzydyna o -dianizydyna
Portuguese português 3,3'-dimetoxibenzidina o -dianisidina
Romanian română 3,3'-dimetoxibenzidină o -dianisidină
Slovak slovenčina 3,3'-dimetoxybenzidín orto -dianizidín
Slovenian slovenščina 3,3'-dimetoksibenzidin o -dianizidin
Finnish suomi 3,3'-dimetoksibentsidiini o -dianisidiini
Swedish svenska 3,3'-dimetoxibensidin o -dianisidin

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

3,3'-dimethoxybenzidine GHS label elements

Everything CLP Annex VI fixes for 3,3'-dimethoxybenzidine, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS08 Health hazard pictogramGHS07 Exclamation mark pictogram

Danger

3,3'-dimethoxybenzidine

  • May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Harmful if swallowed.
  • Obtain special instructions before use.
  • Do not eat, drink or smoke when using this product.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF exposed or concerned:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Rinse mouth.

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open 3,3'-dimethoxybenzidine in the GHS label constructor →

07 · Health hazards

3,3'-dimethoxybenzidine health hazards and exposure limits

3,3'-dimethoxybenzidine hazard summary

3,3'-Dimethoxybenzidine is used as an intermediate in the production of dyes and pigments. No information is available on the acute (short-term), chronic (long-term), reproductive, developmental, or carcinogenic effects of 3,3'-dimethoxybenzidine in humans. Animal studies have reported effects on the liver, kidneys, spleen, and bladder, and endocrine effects, gastritis, intestinal hemorrhage, and weight loss from chronic oral exposure. Increased incidences of tumors in several organs have been reported in rats orally exposed to 3,3'-dimethoxybenzidine or its salt. EPA has classified 3,3'-dimethoxybenzidine as a Group B2, probable human carcinogen.

Source: EPA Hazardous Air Pollutants

3,3'-dimethoxybenzidine carcinogenicity classification

IARC classification Group 2B — Possibly carcinogenic to humans
IARC monographs Volume 4: (1974) Some Aromatic Amines, Hydrazine and Related Substances, N-Nitroso Compounds and Miscellaneous Alkylating Agents

Inadequate evidence of carcinogenicity in humans. Sufficient evidence of carcinogenicity in animals. OVERALL EVALUATION: Group 2B: The agent is possibly carcinogenic to humans.

Source: Hazardous Substances Data Bank (HSDB)

3,3'-Dimethoxybenzidine: reasonably anticipated to be a human carcinogen. /3,3'-Dimethoxylbenzidine and Dyes Metabolized to 3,3'-Dimethoxylbenzidine/

Source: Hazardous Substances Data Bank (HSDB)

An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.

3,3'-dimethoxybenzidine occupational exposure limits

US occupational exposure limits reported for 3,3'-dimethoxybenzidine. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
REL Ca See Appendix ASee Appendix C The National Institute for Occupational Safety and Health (NIOSH)
IDLH A potential occupational carcinogen. (NIOSH, 2024) CAMEO Chemicals
IDLH NIOSH considers o-dianisidine to be a potential occupational carcinogen. Hazardous Substances Data Bank (HSDB)
IDLH Ca [N.D.] The National Institute for Occupational Safety and Health (NIOSH)

These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.

08 · Physical and chemical properties

3,3'-dimethoxybenzidine properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

3,3'-dimethoxybenzidine melting point

Property Value Conditions Source
Melting point 137 °C (278.6 °F) HSDB
137.22 °C (279 °F) NIOSH
137.5 °C (279.5 °F) ICSC

3,3'-dimethoxybenzidine solubility

Property Value Conditions Source
Solubility Sol in alc, benzene, ether HSDB
Sol in chloroform, acetone HSDB
PROBABLY SOL IN MOST ORG SOLVENTS AND LIPIDS HSDB

3,3'-dimethoxybenzidine vapor pressure

Property Value Conditions Source
Vapor pressure negligible ICSC

3,3'-dimethoxybenzidine flash point

Property Value Conditions Source
Flash point 206 °C (402.8 °F) HSDB
206.11 °C (403 °F) NIOSH

3,3'-dimethoxybenzidine lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) The finely powdered carcinogen is a significant dust explosion hazard. HSDB
Combustible Solid NIOSH

3,3'-dimethoxybenzidine vapor density

Property Value Conditions Source
Vapor density 8.43 (air = 1) HSDB
8.5 (air = 1) CAMEO

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

09 · Fire and explosion

3,3'-dimethoxybenzidine fire and explosion behaviour

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

3,3'-dimethoxybenzidine fire potential

Combustible when exposed to heat or flame.

Source: Hazardous Substances Data Bank (HSDB)

10 · Handling and storage

3,3'-dimethoxybenzidine storage and handling

3,3'-dimethoxybenzidine safe storage

Separated from oxidants and food and feedstuffs. Well closed.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

3,3'-dimethoxybenzidine storage conditions

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/

Source: Hazardous Substances Data Bank (HSDB)

3,3'-dimethoxybenzidine incompatible materials

... Can react with oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

3,3'-dimethoxybenzidine reactivity

3,3'-DIMETHOXYBENZIDINE is a weak base. Reacts exothermically with acids. Sensitive to heat, air and prolonged exposure to light.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 3,3'-dimethoxybenzidine in the storage compatibility matrix →

11 · Questions

3,3'-dimethoxybenzidine — frequently asked questions

What is the CAS number of 3,3'-dimethoxybenzidine?

The CAS number of 3,3'-dimethoxybenzidine is 119-90-4. Its EC number is 204-355-4.

What is the chemical formula of 3,3'-dimethoxybenzidine?

The molecular formula of 3,3'-dimethoxybenzidine is C14H16N2O2 and its molecular weight is 244.29 g/mol.

What does a 3,3'-dimethoxybenzidine label have to show?

Under CLP Annex VI the label for 3,3'-dimethoxybenzidine carries the pictograms Health hazard and Exclamation mark and the signal word is Danger.

Is 3,3'-dimethoxybenzidine flammable?

CLP Annex VI assigns 3,3'-dimethoxybenzidine no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it. The flash point reported for it is 206 °C (402.8 °F) (HSDB).

Is 3,3'-dimethoxybenzidine a carcinogen?

Yes. CLP Annex VI classifies 3,3'-dimethoxybenzidine as a category 1A or 1B carcinogen and assigns it H350: may cause cancer. IARC places it in Group 2B: possibly carcinogenic to humans.

What is the melting point of 3,3'-dimethoxybenzidine?

The melting point reported for 3,3'-dimethoxybenzidine is 137 °C (278.6 °F) (HSDB).

How should 3,3'-dimethoxybenzidine be stored?

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/ (Hazardous Substances Data Bank (HSDB))

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