September 16, 2019
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Glycidol is an epoxide and an alcohol, and as such is a highly reactive compound. It is miscible with water but also reacts with it. It decomposes when distilled at atmospheric pressure.

In 1909, chemist Nikolai Prilezhaev at the Warsaw University of Technology prepared glycidol by epoxidizing allyl alcohol with peroxybenzoic acid. This reaction was a breakthrough at the time and became known as the Prilezhaev oxidation. Glycidol is still manufactured in much the same way; but in 2018, a group of companies built a pilot plant in Teesside, UK, to make it via a “green” process.

Glycidol has a chiral center, but it is generally produced and used as the racemic mixture. It is used as a chemical intermediate and in the production of detergents, healthcare products, and industrial paints and coatings.

As shown in the hazard information table, glycidol presents an unusually large number of health risks. These factors were recently acknowledged when the US Food and Drug administration identified 19 substances as potentially harmful constituents of nicotine delivery systems (“e-cigarettes” and “e-liquids”). Glycidol, along with former Molecules of the Week diacetyl and ethylene glycol, is prominent in the FDA list. The agency now requires manufacturers and importers of the delivery systems to report the concentrations of each compound in its products.

Glycidol hazard information

GHS classification*: flammable liquids, category 4
H227—Combustible liquid Chemical Safety Warning
GHS classification: self-reactive substances and mixtures; and organic peroxides, type C
H242—Heating may cause a fire Chemical Safety Warning
GHS classification: acute toxicity, oral, category 4
H302—Harmful if swallowed Chemical Safety Warning
GHS classification: acute toxicity, dermal, category 4
H312—Harmful in contact with skin Chemical Safety Warning
GHS classification: skin corrosion/irritation, category 2
H315—Causes skin irritation Chemical Safety Warning
GHS classification: serious eye damage/eye irritation, category 1
H318—Causes serious eye damage Chemical Safety Warning
GHS classification: acute toxicity, inhalation, category 3
H331—Toxic if inhaled Chemical Safety Warning
GHS classification: specific target organ toxicity, single exposure, respiratory tract irritation, category 3
H335—May cause respiratory irritation Chemical Safety Warning
GHS classification: germ cell mutagenicity, category 2
H341—Suspected of causing genetic defects Chemical Safety Warning
GHS classification: carcinogenicity, category 1B
H350—May cause cancer Chemical Safety Warning
HS classification: reproductive toxicity, category 1B
H360—May damage fertility or the unborn child Chemical Safety Warning

*Globally Harmonized System of Classification and Labeling of Chemicals. Explanation of pictograms.

Glycidol fast facts

CAS Reg. No. 556-52-5
Empirical formula C3H6O2
Molar mass 74.08 g/mol
Appearance Colorless viscous liquid
Boiling point 167 ºC (dec.)
Water solubility Miscible
Chemical Abstract Service - a division of ACS

Learn more about this molecule from CAS, the most authoritative and comprehensive source for chemical information.

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