Product Identification

Product Name

Methimazole

Synonyms

1-Methyl-3H-imidazole-2-thione
2-Mercapto-1-methylimidazole
Methimazole

CAS

60-56-0

Formula

C4H6N2S

Molecular Weight

114.17

EINECS

200-482-4

RTECS

NI8615000

RTECS Class

Tumorigen; Drug; Mutagen; Reproductive Effector; Human Data

Merck

13,6000

Beilstein/Gmelin

108646

Beilstein Reference

5-24-01-00305

Physical and Chemical Properties

Appearance

Beige powder. Stench.

Solubility in water

Soluble

Boiling Point

155

Vapor Pressure

3 (25 C)

Density

1.36 g/cm3

pKa/pKb

11.64 (pKa)

Partition Coefficient

-.02

Heat Of Vaporization

39.2 kJ/mol

Usage

In cyanide-free silver electroplating. Therap cat: antihyperthyroid.

First Aid Measures

Ingestion

Never give anything by mouth to an unconscious person. Get medical aid immediately. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.

Inhalation

Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.

Skin

Get medical aid immediately. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.

Eyes

Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Handling and Storage

Storage

Keep container closed when not in use. Store in a cool, dry, well-ventilated area away from incompatible substances. Hormones and antibiotics room.

Handling

Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Do not get in eyes, on skin, or on clothing. Keep container tightly closed. Do not ingest or inhale.

Hazards Identification

Inhalation

Causes irritation of the mucous membrane and upper respiratory tract. May cause sore throat, headache, and other effects similar to those of ingenstion.

Skin

May cause skin irritation. May cause an allergic reaction in certain individuals.

Eyes

May cause eye irritation.

Ingestion

In high doses may cause gastric irritation, nausea, vomiting, fever, skin rashes, and blood abnormalities including anemia. May be harmful if swallowed. May cause pain and stiffness in joints, paresthesias, headache, and loss or depigmentation of hair.

EC Risk Phrase

R 43 63

EC Safety Phrase

S 22 36/37

UN (DOT)

3335

Exposure Controls/Personal Protection

Personal Protection

Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves and clothing to prevent skin exposure. Clothing: Wear appropriate protective clothing to minimize contact with skin.

Respirators

A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.

Exposure Effects

Chronic exposure may cause reproductive disorders and teratogenic effects. Laboratory experiments have resulted in mutagenic effects. Chronic exposure can affect thyroid function. Chronic exposure may cause blood effects.

Fire Fighting Measures

Flash Point

47

Fire Fighting

Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. To extinguish fire, use water, dry chemical, chemical foam, or alcohol-resistant foam.

Accidental Release Measures

Small spills/leaks

Wash area with soap and water. Clean up spills immediately, using the appropriate protective equipment. Sweep up, then place into a suitable container for disposal. Avoid generating dusty conditions. Provide ventilation.

Stability and Reactivity

Stability

Stable under normal temperatures and pressures. Light sensitive.

Incompatibilities

Strong oxidizing agents.

Decomposition

Nitrogen oxides, carbon monoxide, oxides of sulfur, carbon dioxide.

Transport Information

UN Number

3335

HS Code

2933 29 90