Ingredient Dictionary

DMSO

Dimethyl sulfoxide is a 2-carbon sulfoxide in which the sulfur atom has two methyl substituents.

Definition

Dimethyl sulfoxide is a 2-carbon sulfoxide in which the sulfur atom has two methyl substituents. It has a role as a geroprotector, an alkylating agent, a non-narcotic analgesic, a MRI contrast agent, a polar aprotic solvent, a radical scavenger, an antidote and an Escherichia coli metabolite. It is a volatile organic compound and a sulfoxide.

Source: PubChem

US FDA substance register · UNII YOW8V9698H · registered name Dimethyl sulfoxide · single chemical substance

Source: US FDA Unique Ingredient Identifier (UNII)

Cosmetic roles

Base that dissolves other ingredientsSOLVENT

Safety & regulatory references

Banned: Argentina · ASEAN · Brazil · Canada · China · European Union · South Korea · Taiwan · United Kingdom

Source: ASEAN Cosmetic Directive · EU Cosmetics Regulation · Health Canada Cosmetic Ingredient Hotlist · MFDS (Korea) cosmetic regulatory information · Taiwan FDA cosmetic ingredients · UK cosmetics regulations (OPSS)

Not classified under Korea’s toxic-substance GHS list · existing chemical substance

Source: Korea toxic substances GHS register (NIER)

EU Cosmetics Regulation, Annex II (prohibited substances), entry 338

Source: EU prohibited substances (Annex II)

Health Canada Cosmetic Ingredient Hotlist · prohibited in cosmetics

Source: Health Canada Cosmetic Ingredient Hotlist

Restriction II/338 · Other restriction: ban substances that deplete the ozone layer

Source: EU CosIng ingredient list

More data — names, identifiers, properties, test records, literature

Names & identifiers

DMSOINCI디엠에스오Korean label name (MFDS standard)Methane, 1,1′-sulfinylbis-Synonym

CAS No.chemical registry number: 67-68-5
EC No.EU chemical inventory number: 200-664-3
DTXSIDUS EPA chemical ID: DTXSID2021735
DTXCIDUS EPA compound ID: DTXCID401735

IUPAC: (Methanesulfinyl)methane
Molecular formula: C2H6OS
Molecular weight: 78.13 g/mol

Measured properties

Appearance: Dimethyl sulfoxide appears as a clear liquid, essentially odorless. Closed cup flash point 192 °F. Vapors are heavier than air. Contact with the skin may cause stinging and burning and lead to an odor of garlic on the breath. An excellent solvent that can transport toxic solutes through the skin. High vapor concentrations may cause headache, dizziness, and sedation. · Liquid
Odour: Slightly sulfurous odor · Distinctive garlic or oyster-like odor
Boiling point: 372 °F at 760 mmHg (NTP, 1992) · 63
Melting point: 65.3 °F (NTP, 1992) · 18.5 °C
Solubility: greater than or equal to 100 mg/mL at 68 °F (NTP, 1992) · 1000000 mg/L
Density: 1.101 at 68 °F (USCG, 1999) - Denser than water, will sink · 1.100 at 20 °C/4 °C
Viscosity: 2.47cP at 20 °C · 1.95 mm²/s at 20 °C
Melting/freezing point: 18.5 ℃
Initial boiling point and range: 189 ℃
Flash point: 87 ℃
Upper/lower flammability or explosive limits: 42 / 2.6 %
Vapour pressure: 0.417 ㎜Hg (20℃)
Water solubility: 1000000 ㎎/ℓ (25℃, pH: 7)
Vapour density: 1.1 g/㎤
Relative density: 1.1 (20/4℃)
n-Octanol/water partition coefficient (Kow): -1.35 (log Pow, 20℃)
Auto-ignition temperature: 300 ℃ (1013 hPa)
Decomposition temperature: 189 ℃
Molecular weight: 78.133

Values measured on the substance itself. The KOSHA data are a reference for writing and reviewing safety data sheets, not a specification for a commercial raw material.

Source: PubChem · KOSHA safety data sheets (Korea)

What products actually use it for

What the 25 products reported to the US EPA with this ingredient use it for. Products outside cosmetics are included, so the top few rows are its main uses.

Solvent10
Cleaning agent3
Photosensitive agent2
Flavouring and nutrient2
Preservative1
Fragrance1
Processing aids not otherwise specified1
Surfactant (surface active agent)1

4 other uses

Monomers1
Pharmaceutical (EPA)1
Etching agent1
Chemical reaction regulator1

Source: US EPA CompTox dashboard

Irritation and sensitisation studies

5 skin studies and 3 eye studies are on record.

Classed as moderate1Classed as low3

The studies disagree (the most common conclusion covers 25%), so they do not establish that this ingredient is irritating. These tests are on the raw material itself; irritation at the amount in a finished product is a different question.

See all 8 studies

Moderate or Mild Irritation
skin irritation: in vivo · Screening · OECD Guideline 404 (Acute Dermal Irritation / Corrosion) according to
Category 6.3B (Category 3)
Skin Irritation · Read Across
Not likely to be sensitizing
skin sensitisation: in vivo (non-LLNA) · Screening · equivalent or similar to OECD Guideline 406 (Skin Sensitisation)
Not likely to be sensitizing
skin sensitisation: in vivo (non-LLNA) · Screening · according to OECD Guideline 406 (Skin Sensitisation)
Not likely to be sensitizing
skin sensitisation: in vivo (LLNA) · Screening · equivalent or similar to OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Moderate or Mild Irritation
eye irritation: in vivo · Screening · OECD Guideline 405 (Acute Eye Irritation / Corrosion) according to
Category 6.4A (Category 2A)
Eye Irritation · Read Across
Moderate or Mild Irritation
eye irritation: in vivo · Screening · EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion) Cited as Directive 84/449/EEC, B.5 according to