Substance profile
3,3'-Dichlorobenzidine
3,3'-Dichlorobenzidine is needles from alcohol or benzene.
01 · Identification
What 3,3'-Dichlorobenzidine is
3,3'-Dichlorobenzidine is needles from alcohol or benzene. Its molecular formula is C12H10Cl2N2 and its molecular weight is 253.12 g/mol. It boils at 420 °C, melts at 133 °C.
Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).
02 · Identifiers
3,3'-Dichlorobenzidine identifiers and molecular data
3,3'-Dichlorobenzidine CAS number and EC number
3,3'-Dichlorobenzidine molecular formula and molecular weight
Other names for 3,3'-Dichlorobenzidine
- 3,3'-dichlorobiphenyl-4,4'-ylenediamine
03 · GHS classification
3,3'-Dichlorobenzidine hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
3,3'-Dichlorobenzidine pictograms and signal word
3,3'-Dichlorobenzidine hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Acute toxicity - dermal GHS chapter 3.1 | Category 4 | H312 | GHS07 |
| Skin sensitisation GHS chapter 3.4 | Category 1 or 1A or 1B | H317 | GHS07 |
| Carcinogenicity GHS chapter 3.6 | Category 1A or 1B | H350 | GHS08 |
| Hazardous to the aquatic environment - acute GHS chapter 4.1 | Category 1 | H400 | GHS09 |
| Hazardous to the aquatic environment - chronic GHS chapter 4.1 | Category 1 | H410 | GHS09 |
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'-Dichlorobenzidine hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H350 | May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H312 | Harmful in contact with skin. |
| H317 | May cause an allergic skin reaction. |
| H400 | Very toxic to aquatic life. |
| H410 | Very toxic to aquatic life with long lasting effects. |
This page lists only the codes assigned to 3,3'-Dichlorobenzidine. 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'-Dichlorobenzidine
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'-Dichlorobenzidine 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'-Dichlorobenzidine precautionary statements
CLP Annex VI assigns 13 precautionary statements to 3,3'-Dichlorobenzidine. 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.
Prevention
What to do before and during handling so the hazard never happens.
Response
What to do once exposure, spillage or fire has already happened.
Disposal
What has to happen to the contents and the empty container.
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'-Dichlorobenzidine 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′-дихлоробензидин 3,3′-дихлоробифенил-4,4′-илендиамин |
| Spanish español | 3,3'-Diclorobencidina 3,3'-diclorobifenil-4,4'-ilendiamina |
| Czech čeština | 3,3'-dichlorbenzidin 3,3'-dichlorbifenyl-4,4'-ylendiamin |
| Danish dansk | 3,3'-dichlorbenzidin 3,3'-dichlorbiphenyl-4,4'-ylendiamin |
| German Deutsch | 3,3'-Dichlorbenzidin 3,3'-Dichlorbiphenyl-4,4'-ylendiamin |
| Estonian eesti | 3,3'-diklorobensidiin 3,3'-diklorobifenüül-4,4'-üleendiamiin |
| Greek ελληνικά | 3,3′-διχλωροβενζιδίνη 3,3′-διχλωροδιφαινυλ-4,4′- υλενοδιαμίνη |
| English English | 3,3'-dichlorobenzidine 3,3'-dichlorobiphenyl-4,4'-ylenediamine |
| French français | 3,3'-dichlorobenzidine 3,3'-dichlorobiphényl-4,4'-ylènediamine |
| Croatian hrvatski | 3,3'-dichlorobenzidine 3,3'-dichlorobiphenyl-4,4'-ylenediamine |
| Italian italiano | 3,3'-diclorobenzidina 3,3'-diclorobifenil-4,4'-ilendiamina |
| Latvian latviešu | 3,3′-dihlorbenzidīns 3,3'-dihlorbifenil-4,4'-ilēndiamīns |
| Lithuanian lietuvių | 3,3'-dichlorbenzidinas 3,3'-dichlorbifenil-4,4'-ilenodiaminas |
| Hungarian magyar | 3,3’-diklórbenzidin 3,3’-diklóbifenil-4,4’-iléndiamin |
| Maltese Malti | 3,3'-diklorobenżidina 3,3'-diklorobifenil-4,4'-ilendiammina |
| Dutch Nederlands | 3,3'-dichloorbenzidine 3,3'-dichloorbifenyl-4,4'-yleendiamine |
| Polish polski | 3,3'-dichlorobenzydyna 3,3'-dichlorobifenyl-4,4'-ilenodiamina |
| Portuguese português | 3,3'-diclorobenzidina 3,3'-diclorobifenil-4,4'-ilenodiamina |
| Romanian română | 3,3'-diclor-benzidină 3,3'-diclor-bifenil-4,4'-ilen-diamină |
| Slovak slovenčina | 3,3'-dichlórbenzidín 3,3'-dichlórbifenyl-4,4'-diamín |
| Slovenian slovenščina | 3,3'-diklorobenzidin 3,3'-diklorobifenil-4,4'-ilendiamin |
| Finnish suomi | 3,3'-diklooribentsidiini 3,3'-diklooribifenyl-4,4'-yleenidiamiini |
| Swedish svenska | 3,3'-diklorbensidin 3,3'-diklorbifenyl-4,4'-ylendiamin |
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'-Dichlorobenzidine GHS label elements
Everything CLP Annex VI fixes for 3,3'-Dichlorobenzidine, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
3,3'-Dichlorobenzidine
- May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
- Harmful in contact with skin.
- May cause an allergic skin reaction.
- Very toxic to aquatic life.
- Very toxic to aquatic life with long lasting effects.
- Obtain special instructions before use.
- Avoid breathing dust/fume/gas/mist/vapours/spray.
- Contaminated work clothing should not be allowed out of the workplace.
- Avoid release to the environment.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF ON SKIN:
- IF exposed or concerned:
- Call a POISON CENTER/doctor/… if you feel unwell.
- Get medical advice/attention.
- If skin irritation or rash occurs:
- Wash with plenty of water/…
- Collect spillage.
- Dispose of contents/container to …
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open 3,3'-Dichlorobenzidine in the GHS label constructor →
07 · Health hazards
3,3'-Dichlorobenzidine health hazards and exposure limits
3,3'-Dichlorobenzidine hazard summary
3,3'-Dichlorobenzidine is a gray-to-purple colored crystalline solid. It changes from a solid to a gas very slowly. 3,3'-Dichlorobenzidine salt is the major form in actual use. It is a stable, off-white colored crystalline solid that does not evaporate. Neither 3,3'-dichlorobenzidine nor its salt are found naturally in the environment. They are manufactured for pigments for printing inks, textiles, plastics and enamels, paint, leather, and rubber.
Source: Agency for Toxic Substances and Disease Registry (ATSDR)
3,3'-Dichlorobenzidine carcinogenicity classification
CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: Based on statistically significantly increased tumor incidence in rats, mice and dogs. Additional support is provided by positive evidence of genotoxicity and structural relationship to the known human bladder carcinogen benzidine. HUMAN CARCINOGENICITY DATA: Inadequate. ANIMAL CARCINOGENICITY DATA: Sufficient.
Source: Hazardous Substances Data Bank (HSDB)
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)
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'-Dichlorobenzidine occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | Ca | Occupational Safety and Health Administration (OSHA) |
| PEL | [1910.1007] See Appendix B | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | Ca See Appendix A | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | A potential occupational carcinogen. (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | NIOSH considers 3,3'-dichlorobenzidine (and its salts) to be a potential occupational carcinogens. | 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'-Dichlorobenzidine 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'-Dichlorobenzidine boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 420 °C (788 °F) | NIOSH | |
| 420 °C (788 °F) | at 760 mmHg | CAMEO | |
| 368 °C (694.4 °F) | ICSC |
3,3'-Dichlorobenzidine melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 132.5 °C (270.5 °F) | HSDB | |
| 132.78 °C (271 °F) | NIOSH |
3,3'-Dichlorobenzidine solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Solubility in water: 2-4% at 22 °C and pH 4.6 to pH 8.9 | at 22 °C, Dihydrochloride salt | HSDB |
| Moderately soluble in alcohol; readily soluble in ether | HSDB | ||
| In water, 3.1 mg/L at 25 °C | at 25 °C | HSDB |
3,3'-Dichlorobenzidine autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | 350 °C (662 °F) | ICSC |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Handling and storage
3,3'-Dichlorobenzidine storage and handling
3,3'-Dichlorobenzidine safe storage
Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. Well closed. Store only in original container. Store in an area without drain or sewer access.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
3,3'-Dichlorobenzidine storage conditions
Stable under recommended storage conditions.
Source: Hazardous Substances Data Bank (HSDB)
3,3'-Dichlorobenzidine incompatible materials
Strong oxidizing agents
Source: Hazardous Substances Data Bank (HSDB)
3,3'-Dichlorobenzidine reactivity
A halide- and amine-substituted aromatic compound. Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check 3,3'-Dichlorobenzidine in the storage compatibility matrix →
10 · Questions
3,3'-Dichlorobenzidine — frequently asked questions
What is the CAS number of 3,3'-Dichlorobenzidine?
The CAS number of 3,3'-Dichlorobenzidine is 91-94-1. Its EC number is 202-109-0.
What is the chemical formula of 3,3'-Dichlorobenzidine?
The molecular formula of 3,3'-Dichlorobenzidine is C12H10Cl2N2 and its molecular weight is 253.12 g/mol.
What does a 3,3'-Dichlorobenzidine label have to show?
Under CLP Annex VI the label for 3,3'-Dichlorobenzidine carries the pictograms Health hazard, Exclamation mark and Environment and the signal word is Danger.
Is 3,3'-Dichlorobenzidine flammable?
CLP Annex VI assigns 3,3'-Dichlorobenzidine 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.
Is 3,3'-Dichlorobenzidine a carcinogen?
Yes. CLP Annex VI classifies 3,3'-Dichlorobenzidine 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 exposure limit for 3,3'-Dichlorobenzidine?
The US occupational exposure limit reported for 3,3'-Dichlorobenzidine is Ca (Occupational Safety and Health Administration (OSHA)). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.
What is the boiling point of 3,3'-Dichlorobenzidine?
The boiling point reported for 3,3'-Dichlorobenzidine is 420 °C (788 °F) (NIOSH).
What is the melting point of 3,3'-Dichlorobenzidine?
The melting point reported for 3,3'-Dichlorobenzidine is 132.5 °C (270.5 °F) (HSDB).
How should 3,3'-Dichlorobenzidine be stored?
Stable under recommended storage conditions. (Hazardous Substances Data Bank (HSDB))
Nearby
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