CAS 118-71-8PubChem CID 8369
Maltol
- IUPAC name
- 3-hydroxy-2-methylpyran-4-one
- Molecular formula
- C6H6O3
- Molecular weight
- 126.11 g/mol
- Exact mass
- 126.031694049 Da
- XLogP3
- 0.4
- Topological polar surface area
- 46.5 Ų
- Hydrogen-bond donors
- 1
- Hydrogen-bond acceptors
- 3
- Covalent units
- 1
- Defined stereocentres
- 0
Also known as
3-Hydroxy-2-methyl-4H-pyran-4-one3-Hydroxy-2-methyl-4-pyroneLarixinic acidPalatoneLarixic acidTalmonVetolVeltol
16 more reported names
Corps praline4H-Pyran-4-one, 3-hydroxy-2-methyl-2-Methyl-3-hydroxy-4-pyrone2-Methyl pyromeconic acid2-Methylpyromeconic acid2-Methyl-3-hydroxypyrone3-Hydroxy-2-methyl-gamma-pyrone2-Methyl-3-oxy-gamma-pyroneFEMA No. 2656NSC 2829NSC-2829NSC-404458Ins no.636Ins-636BRN 01121693A9RD92BS4
External database identifiers
- ChEBI:CHEBI:69438
- ChEMBL:CHEMBL31422
- EPA DTXSID:DTXSID0025523
- PubMed:23007530
- PubMed:22831747
- PubMed:22826760
- PubMed:22687564
- PubMed:22569684
- PubMed:22542289
- PubMed:22504362
- PubMed:22476413
- PubMed:22461871
- PubMed:22417522
- PubMed:22315575
- PubMed:22296279
Evidence from additional scientific databases
NIH PubChem PUG-View
Exact identifier match8369
Attributed physical-property, hazard, environmental and use annotations.
- Boiling Point: 199 °F at 760 mmHg (Sublimes) (NTP, 1992) Source: CAMEO Chemicals
- Boiling Point: Sublimes at 93 °C Source: Hazardous Substances Data Bank (HSDB)
- Color/Form: Monoclinic prisms from chloroform, orthorhombic bypyramidal crystals + monoclinic prisms from 50% alcohol Source: Hazardous Substances Data Bank (HSDB)
- Color/Form: White crystalline powder Source: Hazardous Substances Data Bank (HSDB)
- Dissociation Constants: pKa = 8.6 Source: Hazardous Substances Data Bank (HSDB)
- LogP: log Kow = 0.09 Source: Hazardous Substances Data Bank (HSDB)
- LogP: 0.09 Source: Human Metabolome Database (HMDB)
- Melting Point: 324 to 327 °F (NTP, 1992) Source: CAMEO Chemicals
- Melting Point: 161.5 °C Source: Hazardous Substances Data Bank (HSDB)
- Melting Point: 161 - 162 °C Source: Human Metabolome Database (HMDB)
- Odor: Fragrant, caramel-like odor Source: Hazardous Substances Data Bank (HSDB)
- Odor: Characteristic caramel-butterscotch odor and suggestive of a fruity-strawberry aroma in dilute solution Source: Hazardous Substances Data Bank (HSDB)
- Odor: Caramel-like odor, reminiscent of freshly baked cakes Source: Hazardous Substances Data Bank (HSDB)
- Physical Description: Maltol is a white crystalline powder with a fragrant caramel-butterscotch odor. pH (5% aqueous solution) 5.3. (NTP, 1992) Source: CAMEO Chemicals
- Physical Description: Other Solid; Dry Powder; Liquid Source: EPA Chemical Data Reporting (CDR)
- Physical Description: Solid with a fragrant odor like caramel; [Merck Index] White powder; [Alfa Aesar MSDS] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Physical Description: Solid Source: Human Metabolome Database (HMDB)
- Physical Description: White crystalline powder; Caramel-butterscotch aroma Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
- Solubility: 1 to 10 mg/mL at 72 °F (NTP, 1992) Source: CAMEO Chemicals
- Solubility: In water, 10900 mg/L at 15 °C Source: Hazardous Substances Data Bank (HSDB)
- Solubility: One gram dissolves in 82 mL water, 80 mL glycerin, 21 mL alcohol, 28 mL propylene glycol; Freely soluble in hot water, chloroform; sparingly soluble in benzene, ether, petroleum ether; soluble in alkali hydroxides giving yellow solutions Source: Hazardous Substances Data Bank (HSDB)
- Solubility: 10.9 mg/mL at 15 °C Source: Human Metabolome Database (HMDB)
- Solubility: Sparingly soluble in water, soluble in propylene glycol Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
- Solubility: Soluble (in ethanol) Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
- Vapor Pressure: 0.000507 [mmHg] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Vapor Pressure: 3.26X10-4 mm Hg at 25 °C (extrapolated from reduced pressure boiling point) Source: Hazardous Substances Data Bank (HSDB)
- pH: pH of 0.5% aqueous solution = 5.3 Source: Hazardous Substances Data Bank (HSDB)
- 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. If symptoms (such as redness or irritation) develop, immediately transport the victim to a hospital.; 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. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.; 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. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not availabl Source: CAMEO Chemicals
- Note: This chemical does not meet GHS hazard criteria for 15.5% (303 of 1955) of reports. Source: European Chemicals Agency (ECHA)
- Signal: Warning Source: European Chemicals Agency (ECHA)
- GHS Hazard Statements: H302 (84.5%): Harmful if swallowed [Warning Acute toxicity, oral] Source: European Chemicals Agency (ECHA)
- Precautionary Statement Codes: P264, P270, P301+P317, P330, 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 1955 reports by companies from 20 notifications to the ECHA C&L Inventory.; Reported as not meeting GHS hazard criteria per 303 of 1955 reports by companies.; There are 18 notifications provided by 1652 of 1955 reports by companies with hazard statement code(s).; 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: NITE-CMC
- GHS Hazard Statements: H302: Harmful if swallowed [Warning Acute toxicity, oral]; H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity] Source: NITE-CMC
- Precautionary Statement Codes: P203, P264, P270, P280, P301+P317, P318, P330, P405, and P501 (click each P-code to see the statement) Source: NITE-CMC
- Signal: Warning Source: Hazardous Substances Data Bank (HSDB)
- GHS Hazard Statements: H302: Harmful if swallowed [Warning Acute toxicity, oral]; H315: Causes skin irritation [Warning Skin corrosion/irritation]; H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation] Source: Hazardous Substances Data Bank (HSDB)
- Precautionary Statement Codes: P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P319, P321, P330, P332+P317, P337+P317, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement) Source: Hazardous Substances Data Bank (HSDB)
- Toxicity Summary: IDENTIFICATION AND USE: Maltol is a white crystalline powder. It is used as a flavoring agent, to impart "freshly baked" odor and flavor to breads and cakes. It is also used as medication. HUMAN EXPOSURE AND TOXICITY: Maltol at concentrations ranging from 0.1 to 1.5 umol/mL induced sister chromatid exchanges in human lymphocytes. It was suggested that these results were due to an indirect action of maltol and not to its direct reactivity with DNA. ANIMAL STUDIES: Eight female mice were fed a diet containing maltol at a level of 0.5% (w/w) for 21 weeks, calculated to provide an average daily intake of 750 mg/kg bw. At termination, no differences in general health, behavior, body-weight gain or relative liver weights were reported. Gross and microscopic examination revealed no histological abnormalities in the livers of the treated mice when compared with the controls. A three-generation study of reproductive toxicity was conducted, in which groups of 20 male and 20 female rats were given diets containing maltol at concentrations resulting in 100, 200 or 400 mg/kg bw per day. On day 134, animals of the F1 generation showed signs of sialodacryodenitis due to a contagious virus. No dea Source: Hazardous Substances Data Bank (HSDB)
- Environmental Bioconcentration: An estimated BCF of 3 was calculated in fish for maltol(SRC), using a log Kow of 0.09(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), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that maltol is expected to have very high mobility in soil(SRC). Volatilization of maltol from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 5.0X10-9 atm-cu m/mole(SRC), derived from its extrapolated vapor pressure, 3.26X10-4 mm Hg(2), and water solubility, 1.09X10+4 mg/L(3). Maltol is not expected to volatilize from dry soil surfaces(SRC) based upon its extrapolated vapor pressure(2); however, maltol does have a characteristic fragrant odor(4) even though it exists as a solid. Biodegradation data in soil were not available(SRC, 2016). Source: Hazardous Substances Data Bank (HSDB)
- Environmental Fate: AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that maltol 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 5.0X10-9 atm-cu m/mole(SRC), derived from its extrapolated vapor pressure, 3.26X10-4 mm Hg(2), and water solubility, 1.09X10+4 mg/L(4). According to a classification scheme(5), an estimated BCF of 3(SRC), from its log Kow of 0.09(6) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data in water were not available(SRC, 2016). Maltol is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). Maltol is an olefinic compound and olefins in surface waters exposed to sunlight react with photo-oxidants with a half-life on the order of 25 days(7). 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), maltol, which has an extrapolated vapor pressure of 3.26X10-4 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase maltol 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 7.7 hours(SRC), calculated from its rate constant of 5.0X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(2). Vapor-phase maltol is also degraded in the atmosphere by reaction with ozone(SRC); the half-life for this reaction in air is estimated to be 21 hours(SRC), calculated from its rate constant of 1.3X10-17 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(2). Maltol absorbs at wavelengths >290 nm(3) and, therefore, may be susceptible to direct photolysis by sunlight(SRC). Source: Hazardous Substances Data Bank (HSDB)
- Consumer Uses: Fragrance Source: EPA Chemical Data Reporting (CDR)
- Industry Uses: Fragrance; Flavoring and nutrient Source: EPA Chemical Data Reporting (CDR)
- Sources/Uses: Present in the bark of young larch trees, pine needles, chicory, wood tars and oils, and roasted malt; Used as a flavoring agent (gives bread and cakes a freshly baked odor); [Merck Index] Used as a flavoring agent, nutritive sweetener, and processing aid for food; [FDA] Permitted for use as an inert ingredient in non-food pesticide products; [EPA] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
- Uses: Flavoring agent, to impart "freshly baked" odor and flavor to breads and cakes. Source: Hazardous Substances Data Bank (HSDB)
- Uses: Reported uses (ppm):; Table: Reported uses (ppm): (Flavor and Extract Manufacturers' Association, 1994) [Table#8335] Source: Hazardous Substances Data Bank (HSDB)
- Uses: MEDICATION 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
| Source | Result | Checked |
|---|---|---|
| NIH PubChem PUG-View | Exact match | 2026-08-31 |
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.