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

Methylisothiazolinone

Methylisothiazolinone is colorless prisms.

CAS 2682-20-4 C4H5NOS 115.16 g/mol Danger

01 · Identification

What Methylisothiazolinone is

Methylisothiazolinone is colorless prisms. Its molecular formula is C4H5NOS and its molecular weight is 115.16 g/mol. It melts at 50.5 °C.

Under the GHS it carries the signal word Danger.

CAS number2682-20-4
EC number220-239-6
Index number613-326-00-9
Molecular formulaC4H5NOS
Molecular weight115.16 g/mol

Other names for Methylisothiazolinone

  • 2-methylisothiazol-3(2H)-one

02 · GHS classification

Hazards and label elements

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

Signal wordDanger
Hazard statements assigned to Methylisothiazolinone
CodeHazard statement
H330 Fatal if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H314 Causes severe skin burns and eye damage.
H318 Causes serious eye damage.
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Supplemental EU statements: EUH071

Precautionary statements: P260, P261, P270, P271, P272, P273, P280, P301, P302, P304, P305, P310, P313, P330, P331, P333, P338, P352, P391, P501

03 · Physical and chemical properties

Methylisothiazolinone 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.

Property Value Conditions Source
Boiling point 93 °C (199.4 °F) at 0.03 mmHg (reduced pressure) HSDB
Melting point 50.5 °C (122.9 °F) range, midpoint shown HSDB
Density 1.19 g/cm³ at 20 °C HSDB
1.35 g/cm³ at 25 °C HSDB
Solubility Solubility in: acetonitrile 78.6; methanol 79.1; hexane 2.371; xylenol 15.65 (g/100 mL) HSDB
Vapor pressure 0.062 mmHg at 25 °C HSDB

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

04 · Handling and storage

Storing and handling Methylisothiazolinone

Storage conditions

Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Materials to avoid: Strong oxidizing agents, Amines, Mercaptans, Reducing agents.

Source: Hazardous Substances Data Bank (HSDB)

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

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