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Annex II Entry 408 20/10/2010

Pyrocatechol (Catechol)

Pyrocatechol (Catechol) 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: 408

Chemical identity and properties

PubChem 2D chemical structure for CAS 120-80-9
CAS 120-80-9PubChem CID 289

Catechol

Catechol is a benzenediol comprising of a benzene core carrying two hydroxy substituents ortho to each other. It has a role as a genotoxin, an allelochemical and a plant metabolite. It is a conjugate acid of a catecholate(1-). ChEBI

IUPAC name
benzene-1,2-diol
Molecular formula
C6H6O2
Molecular weight
110.11 g/mol
Exact mass
110.036779430 Da
XLogP3
0.9
Topological polar surface area
40.5 Ų
Hydrogen-bond donors
2
Hydrogen-bond acceptors
2
Covalent units
1
Defined stereocentres
0

Also known as

pyrocatechol1,2-dihydroxybenzene1,2-benzenediolpyrocatechin2-hydroxyphenolo-Dihydroxybenzeneo-Hydroxyphenolo-Benzenediol
16 more reported names
o-Dioxybenzeneo-HydroquinonePhthalhydroquinonePyrocatechineo-PhenylenediolOxyphenic acidFouramine PCHPelagol Grey CDurafur developer CCatechin (phenol)Fourrine 68Benzene, o-dihydroxy-Catechol (phenol)o-DiphenolC.I. Oxidation Base 26ortho-Hydroxyphenol
External database identifiers

Evidence from additional scientific databases

NIH PubChem PUG-View
Exact identifier match289

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. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whene 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: Water wash immediately - If this chemical contacts the skin, immediately wash the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and wash the skin with water. If symptoms occur after washing, get medical attention immediately.; 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: H301: Toxic if swallowed [Danger Acute toxicity, oral]; H311: Toxic in contact with skin [Danger Acute toxicity, dermal]; H315: Causes skin irritation [Warning Skin corrosion/irritation]; H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]; H350: May cause cancer [Danger Carcinogenicity] Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • Precautionary Statement Codes: P203, P262, P264, P264+P265, P270, P280, P301+P316, P302+P352, P305+P351+P338, P316, P318, P321, P330, P332+P317, P337+P317, P361+P364, P362+P364, 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: H301 (16.4%): Toxic if swallowed [Danger Acute toxicity, oral]; H302 (83.6%): Harmful if swallowed [Warning Acute toxicity, oral]; H311 (16.4%): Toxic in contact with skin [Danger Acute toxicity, dermal]; H312 (83.6%): Harmful in contact with skin [Warning Acute toxicity, dermal]; H315 (> 99.9%): Causes skin irritation [Warning Skin corrosion/irritation]; H317 (12.6%): May cause an allergic skin reaction [Warning Sensitization, Skin]; H319 (94.6%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H341 (16.4%): Suspected of causing genetic defects [Warning Germ cell mutagenicity]; H350 (11.4%): May cause cancer [Danger Carcinogenicity] Source: European Chemicals Agency (ECHA)
  • Precautionary Statement Codes: P203, P261, P262, P264, P264+P265, P270, P272, P280, P301+P316, P301+P317, P302+P352, P305+P351+P338, P316, P317, P318, P321, P330, P332+P317, P333+P317, P337+P317, P361+P364, P362+P364, 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 2962 reports by companies from 34 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: Warning Source: European Chemicals Agency (ECHA)
  • GHS Hazard Statements: H317 (100%): May cause an allergic skin reaction [Warning Sensitization, Skin]; H412 (100%): Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard] Source: European Chemicals Agency (ECHA)
  • Precautionary Statement Codes: P261, P272, P273, P280, P302+P352, P321, P333+P317, P362+P364, and P501 (click each P-code to see the statement) Source: European Chemicals Agency (ECHA)
  • ECHA C&L Notifications Summary: The GHS information provided by 1 company from 1 notification to the ECHA C&L Inventory. Source: European Chemicals Agency (ECHA)
  • GHS Hazard Statements: H315 (100%): Causes skin irritation [Warning Skin corrosion/irritation]; H319 (100%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H412 (100%): Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard] Source: European Chemicals Agency (ECHA)
  • NFPA Health Rating: 3 - Materials that, under emergency conditions, can cause serious or permanent injury. 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)
  • Cosmetic Ingredient Review Conclusion: The CIR Expert Panel concludes that Pyrocatechol is unsafe for use in leave-on products, and that the available data are insufficient to support the safety of Pyrocatechol as used in hair dyes. Source: Cosmetic Ingredient Review (CIR)
  • Cosmetic Ingredient Review Finding(s): The ingredient is unsafe for use in cosmetics; Ingredients for which the data are insufficient and their use in cosmetics is not supported Source: Cosmetic Ingredient Review (CIR)
  • Toxicity Summary: IDENTIFICATION AND USE: Catechol is a tablet or colorless crystal, prism or aqueous solution, which discolors to brown on exposure to air and light. It has a faint characteristic odor. It is used as antioxidant in the rubber, chemical, photographic, dye, fat, and oil industries. It was formerly used as an antiseptic. Catechol was found unsafe for use in cosmetics. HUMAN EXPOSURE AND TOXICITY: Catechol contact with the skin has been known to cause an eczematous dermatitis. It is highly irritating upon direct contact; severe eye and deep skin burns result. Well absorbed by skin. Systemic toxicity similar to that of phenol however, catechol may be more likely to cause convulsions and hypertension. At high doses, renal and liver injury may occur. Absorption through the skin, in a few instances, has resulted in symptoms of illness resembling closely those induced by phenol, except for certain central effects (convulsions) that were more marked. Death apparently is initiated by respiratory failure. Catechol was found to be a more harmful toxin than phenol in human blood cells in vitro, since it provokes statistically significant changes in the function of erythrocytes even at low doses. Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Bioconcentration: An estimated BCF of 3 was calculated for catechol(SRC), using a log Kow of 0.88(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), a Koc value of 118(2), indicates that catechol is expected to have high mobility in soil(SRC). Volatilization of catechol from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.2X10-9 atm-cu m/mole(SRC), based upon its vapor pressure, 3.66X10-3 mm Hg(3), and water solubility, 4.61X10+5 mg/L(4). Catechol is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). The percent biodegradation after 6 months in various loam soils ranged from 24 to 50%(5), indicating that biodegradation is a moderate environmental fate process in soil(SRC). Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: AQUATIC FATE: Based on a classification scheme(1), a Koc value of 118(2), indicates that catechol is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 1.20X10-9 atm-cu m/mole(SRC), derived from its vapor pressure, 3.66X10-3 mm Hg(4), and water solubility, 4.61X10+5 mg/L(5). According to a classification scheme(6), an estimated BCF of 3(SRC), from its log Kow of 0.88(7) and a regression-derived equation(8), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Utilizing the Japanese MITI test, 83% of the Theoretical BOD was reached in 2 weeks(9) indicating that biodegradation is an important environmental fate process in water(SRC). 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), catechol, which has a vapor pressure of 3.66X10-3 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase catechol 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 2.8 hrs(SRC), calculated from its rate constant of 1.04X10-10 cu cm/molecule-sec at 25 °C(3). Catechol in its nonionized form will not be subject to direct photolysis since this form does not absorb light above 300 nm in methanol solution(4). Reaction of catechol with nitrate radicals during nighttime may be an important removal process based on a rate constant of 3.8X10-12 cu cm/molecule sec for the reaction of phenol with nitrate radicals(2) which corresponds to a half-life of 15 minutes at an atmospheric concentration of 2X10+8 nitrate radicals per cu cm(SRC). The ionized form of catechol may photolyze based on an absorption maximum at 313 nm in basic aqueous solution(6) and at 289 nm in basic methanol solution(4). Therefore, catechol may be susceptible 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.

Record details

Chemical name

Pyrocatechol (Catechol)

Regulatory information

Regulation

(EC) 2009/1223

See every entry this act set

Identified ingredients

Key data

Annex
Entry number
408

Inventory links for Pyrocatechol (Catechol)

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

Annex II 409
Nearby record in the same annex

Pyrogallol

CAS: 87-66-1
EC: 201-762-9

What Annex II means for Pyrocatechol (Catechol)

Pyrocatechol (Catechol) 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.

This record is linked to 1 CosIng inventory ingredient for name and identifier cross-reference. 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).

Frequently asked questions

Yes. Pyrocatechol (Catechol) 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 120-80-9 is the unique numerical identifier assigned to Pyrocatechol (Catechol) 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.

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 Pyrocatechol (Catechol)

This page summarizes one Annex II record for Pyrocatechol (Catechol) 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 Pyrocatechol (Catechol), but confirm any final regulatory decision against the current official annex wording and source files.

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