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

Guaiacol

Guaiacol is faintly yellowish, limpid, oily liquid or yellow crystals with an aromatic odor.

CAS 90-05-1 C7H8O2 124.14 g/mol Warning

01 · Identification

What Guaiacol is

Guaiacol is faintly yellowish, limpid, oily liquid or yellow crystals with an aromatic odor. Its molecular formula is C7H8O2 and its molecular weight is 124.14 g/mol. It boils at 205 °C, melts at 32 °C, is soluble in water.

Under the GHS it carries the signal word Warning.

02 · Identifiers

Guaiacol identifiers and molecular data

Guaiacol CAS number and EC number

CAS number90-05-1
EC number201-964-7
Index number (CLP Annex VI)604-031-00-6

Guaiacol molecular formula and molecular weight

Molecular formulaC7H8O2
Molecular weight124.14 g/mol

03 · GHS classification

Guaiacol hazard classification

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

Guaiacol pictograms and signal word

Signal wordWarning

Guaiacol hazard class and category

GHS hazard classes Guaiacol falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Skin corrosion/irritation GHS chapter 3.2 Category 2 H315 GHS07
Serious eye damage/eye irritation GHS chapter 3.3 Category 2A H319 GHS07

Guaiacol hazard statements (H-codes)

Hazard statements assigned to Guaiacol
CodeHazard statement
H302 Harmful if swallowed.
H315 Causes skin irritation.
H319 Causes serious eye irritation.

This page lists only the codes assigned to Guaiacol. 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 Guaiacol

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 Guaiacol 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

Guaiacol precautionary statements

CLP Annex VI assigns 13 precautionary statements to Guaiacol. 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

Guaiacol 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 гвайакол
Spanish español Guayacol
Czech čeština guajakol 2-methoxyfenol
Danish dansk guaiacol
German Deutsch Guajakol 2-Methoxyphenol
Estonian eesti guajakool
Greek ελληνικά γουαϊακόλη
English English guaiacol
French français gaïacol
Croatian hrvatski gvajakol
Italian italiano guaiacolo 2-metossifenolo
Latvian latviešu gvajakols
Lithuanian lietuvių gvajakolis
Hungarian magyar gvajakol
Maltese Malti gwajakol
Dutch Nederlands guajacol
Polish polski gwajakol 2-metoksyfenol2-hydroksyanizol
Portuguese português guaiacol
Romanian română guaiacol
Slovak slovenčina guajakol
Slovenian slovenščina gvajakol
Finnish suomi guajakoli
Swedish svenska guajakol

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

Guaiacol GHS label elements

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

GHS07 Exclamation mark pictogram

Warning

Guaiacol

  • Harmful if swallowed.
  • Causes skin irritation.
  • Causes serious eye irritation.
  • Wash thoroughly after handling.
  • Do not eat, drink or smoke when using this product.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF IN EYES:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Rinse mouth.
  • If skin irritation occurs:
  • If eye irritation persists:
  • Remove contact lenses, if present and easy to do. Continue rinsing.
  • Wash with plenty of water/

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

Need this as an actual label? Open Guaiacol in the GHS label constructor →

07 · Health hazards

Guaiacol health hazards and exposure limits

Guaiacol hazard summary

Emergency treatment: Phenol and related agents; [HSDB] May cause skin and eye irritation; Can be absorbed through skin; [CAMEO] Causes somnolence and acts as a general anesthetic; Causes elevation of transaminase enzymes; Mild eye irritant in rabbits; [RTECS] Safe when used as a flavoring agent in food; [JECFA] An irritant; [MSDSonline] See Phenol.

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

08 · Physical and chemical properties

Guaiacol 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.

Guaiacol boiling point

Property Value Conditions Source
Boiling point 205 °C (401 °F) HSDB
205 °C (401 °F) range, midpoint shown, at 760 mmHg CAMEO
204.5 °C (400.1 °F) range, midpoint shown JECFA

Guaiacol melting point

Property Value Conditions Source
Melting point 32 °C (89.6 °F) HSDB
28 °C (82.4 °F) CAMEO

Guaiacol density

Property Value Conditions Source
Density 1.13 g/cm³ at 21.39 °C CAMEO
1.1287 g/cm³ at 21 °C HSDB
1.1345 g/cm³ range, midpoint shown JECFA

Guaiacol solubility

Property Value Conditions Source
Solubility Soluble in carbon tetrachloride HSDB
Miscible with alcohol, chloroform, ether, oils, glacial acetic acid; slightly soluble in petroleum ether; soluble in sodium hydroxide solution HSDB
1 g is soluble in 60-70 mL water, in 1 mL glycerol o-methoxyphenol HSDB

Guaiacol vapor pressure

Property Value Conditions Source
Vapor pressure 0.103 mmHg HSDB
5 mmHg at 78.89 °C CAMEO
0.1 mmHg Haz-Map

Guaiacol flash point

Property Value Conditions Source
Flash point 82.22 °C (180 °F) HSDB

Guaiacol vapor density

Property Value Conditions Source
Vapor density 4.27 (air = 1) CAMEO

Guaiacol odor threshold

Property Value Conditions Source
Odor threshold Odor threshold = 0.001-0.002 ppm (recognition) Haz-Map

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

09 · Fire and explosion

Guaiacol 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.

Guaiacol fire potential

This material is combustible when exposed to heat or flame.

Source: Hazardous Substances Data Bank (HSDB)

10 · Handling and storage

Guaiacol storage and handling

Guaiacol storage conditions

Store in tight, light-resistant container as defined in the USP-NF. This material should be handled and stored per label instructions to ensure product integrity.

Source: Hazardous Substances Data Bank (HSDB)

Guaiacol reactivity

O-METHOXYPHENOL may react with oxidizing materials. It forms salts readily with bases. (NTP, 1992)

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Guaiacol in the storage compatibility matrix →

11 · Questions

Guaiacol — frequently asked questions

What is the CAS number of Guaiacol?

The CAS number of Guaiacol is 90-05-1. Its EC number is 201-964-7.

What is the chemical formula of Guaiacol?

The molecular formula of Guaiacol is C7H8O2 and its molecular weight is 124.14 g/mol.

What does a Guaiacol label have to show?

Under CLP Annex VI the label for Guaiacol carries the pictogram Exclamation mark and the signal word is Warning.

Is Guaiacol flammable?

CLP Annex VI assigns Guaiacol 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 82.22 °C (180 °F) (HSDB).

Is Guaiacol a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Guaiacol. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the boiling point of Guaiacol?

The boiling point reported for Guaiacol is 205 °C (401 °F) (HSDB).

What is the melting point of Guaiacol?

The melting point reported for Guaiacol is 32 °C (89.6 °F) (HSDB).

How should Guaiacol be stored?

Store in tight, light-resistant container as defined in the USP-NF. This material should be handled and stored per label instructions to ensure product integrity. (Hazardous Substances Data Bank (HSDB))

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