CHLOROMETHYL METHYL ETHER
(AND RELATED COMPOUNDS)

Chloromethyl methyl ether
(Methyl chloromethyl ether; CMME)
CAS 107-30-2

ClCH₂ OCH₃

Colorless liquid
bp 55 to 59 °C, mp -104 °C
Hydrolyzes in water

Similar to HCl

260 mmHg at 20 °C

15 °C

Not available

LC₅₀ inhal (rat) 55 ppm (180 mg/m³; 7 h)

LD₅₀ oral (rat) 817 mg/kg

OSHA "select carcinogen"; highly irritating to the eyes, skin, and respiratory tract.

The acute toxicity of chloromethyl methyl ether is moderate to high. Inhalation of the vapor is severely irritating to the eyes, skin, nose, and respiratory tract, and causes sore throat, fever, chills, and difficulty breathing. Exposure to high concentrations can lead to delayed pulmonary edema, which can be fatal. Eye or skin contact with the liquid can result in severe and painful burns. Ingestion of this substance may lead to severe burns of the mouth and stomach and can be fatal.

Chloromethyl methyl ether is regulated by OSHA as a carcinogen (29 CFR 1910.1006) and is listed in IARC Group 1 ("carcinogenic to humans"). This substance is classified as a "select carcinogen" under the criteria of the OSHA Laboratory Standard. Note also that some commercial samples of chloromethyl methyl ether contain up to 7% of highly carcinogenic bis(chloromethyl) ether. Hydrolysis of chloromethyl methyl ether produces HCl and formaldehyde, which can recombine to form bis(chloromethyl) ether. No information is available on the reproductive and developmental toxicity of chloromethyl methyl ether. Odor does not provide adequate warning of the harmful presence of this carcinogenic substance.

Chloromethyl methyl ether is highly flammable. Fires involving this substance should be extinguished with carbon dioxide or dry chemical extinguishers.

Chloromethyl methyl ether decomposes in water to form HCl and formaldehyde, and reacts readily with oxidizing agents.

Because of its carcinogenicity, chloromethyl methyl ether should be handled using the "basic prudent practices" of Chapter 5.C, supplemented by the additional precautions for work with compounds of high chronic toxicity (Chapter 5.D) and high flammability (Chapter 5.F). In particular, work with this substance should be conducted in a fume hood to prevent exposure by inhalation, and appropriate impermeable gloves and splash goggles should be worn at all times to prevent skin and eye contact. Chloromethyl methyl ether is also highly flammable and should be used only in areas free of ignition sources; quantities greater than 1 liter should be stored in tightly sealed metal containers in areas separate from oxidizers in secondary containers.

In the event of skin contact, immediately wash with soap and water and remove contaminated clothing. In case of eye contact, promptly wash with copious amounts of water for 15 min (lifting upper and lower lids occasionally) and obtain medical attention. If chloromethyl methyl ether is ingested, obtain medical attention immediately. If large amounts of this compound are inhaled, move the person to fresh air and seek medical attention at once.

In the event of a spill, remove all ignition sources, soak up the chloromethyl methyl ether with a spill pillow or absorbent material, place in an appropriate container, and dispose of properly. Respiratory protection may be necessary in the event of a large spill or release in a confined area.

Excess chloromethyl methyl ether and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines.

The information in this LCSS has been compiled by a committee of the National Research Council from literature sources and Material Safety Data Sheets and is believed to be accurate as of July 1994. This summary is intended for use by trained laboratory personnel in conjunction with the NRC report Prudent Practices in the Laboratory: Handling and Disposal of Chemicals. This LCSS presents a concise summary of safety information that should be adequate for most laboratory uses of the title substance, but in some cases it may be advisable to consult more comprehensive references. This information should not be used as a guide to the nonlaboratory use of this chemical.

Copyright 1995 National Academy of Sciences. All rights reserved.