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

1,2-dihydroxybenzene

1,2-dihydroxybenzene is monoclinic tablets, prisms from toluene its aqueous solutions soon turn brown with a faint characteristic odor.

CAS 120-80-9 C6H6O2 110.11 g/mol Danger

01 · Identification

What 1,2-dihydroxybenzene is

1,2-dihydroxybenzene is monoclinic tablets, prisms from toluene its aqueous solutions soon turn brown with a faint characteristic odor. Its molecular formula is C6H6O2 and its molecular weight is 110.11 g/mol. It boils at 246 °C, melts at 105 °C.

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

CAS number120-80-9
EC number204-427-5
Index number604-016-00-4
Molecular formulaC6H6O2
Molecular weight110.11 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for 1,2-dihydroxybenzene

  • pyrocatechol

02 · GHS classification

Hazards and label elements

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

Signal wordDanger
Hazard statements assigned to 1,2-dihydroxybenzene
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H315 Causes skin irritation.
H319 Causes serious eye irritation.

Precautionary statements: P201, P264, P270, P280, P301, P302, P305, P308, P310, P313, P330, P332, P337, P338, P352

03 · Physical and chemical properties

1,2-dihydroxybenzene 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.

Property Value Conditions Source
Boiling point 245.56 °C (474 °F) NIOSH
245.5 °C (473.9 °F) ICSC
Melting point 105 °C (221 °F) HSDB
Density 1.344 g/cm³ HSDB
1.371 g/cm³ HSDB
1.34 g/cm³ NIOSH
Solubility Soluble in chloroform, ether; very soluble in pyridine, aqueous alkalis HSDB
Very soluble in alcohol, ethyl ether, acetate HSDB
In water, 4.61X10+5 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 0.03 mmHg at 20 °C HSDB
10 mmHg at 118.3 °C HSDB
10 mmHg at 117.78 °C NIOSH
Flash point 126.67 °C (260 °F) HSDB
127.2 °C (261 °F) open cup HSDB
127 °C (260.6 °F) HSDB
Autoignition temperature 510 °C (950 °F) HSDB
Lower explosive limit (LEL) 1.4 % by volume NIOSH
Flammability lower limit (vapor in air): 1.97% HSDB
Upper explosive limit (UEL) Not Applicable. Combustible solid (USCG, 1999) CAMEO
NA OSHA
Vapor density 3.79 (air = 1) HSDB
3.8 (air = 1) ICSC
Odor threshold detection: 8.0 mg/L HSDB
Critical temperature and pressure 526.85 °C (980.3 °F) HSDB

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

04 · Handling and storage

Storing and handling 1,2-dihydroxybenzene

Storage conditions

Separated from strong oxidants, food and feedstuffs. Keep in the dark. Ventilation along the floor.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Can react vigorously with oxidizing materials

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

POISONOUS GASES MAY BE PRODUCED WHEN HEATED. CATECHOL may form toxic fumes at high temperatures. (USCG, 1999). This compound can react with acid chlorides, acid anhydrides, bases and oxidizing agents. It reacts violently on contact with concentrated nitric acid. It acts as a reducing agent (NTP, 1992).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 1,2-dihydroxybenzene in the storage compatibility matrix →

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