What is Chloromethane?

Chloromethane (chemical formula: CH₃Cl), also known as methyl chloride, is a colourless and odourless (or slightly sweet smelling) gas. Chloromethane does not mix with water, but is soluble in alcohol, chloroform, benzene, carbon tetrachloride and glacial acetic acid. 

What is Chloromethane used for?

Chloromethane is a methylating agent used for producing silicones, butyl rubbers, resins, plastics, dyes, perfumes, tetramethyl lead, methyl cellulose, methylene chloride and methyl mercaptan, pesticides, pharmaceuticals, ethers, methyl ethers and reagents in chemical production.

It is also a potent narcotic which has been used as a local anaesthetic. 

Chloromethane was also commonly used as a refrigerant (called Freon-40), however this use has largely been discontinued. 

Chloromethane Hazards

The routes of exposure for chloromethane include inhalation, ingestion, skin and eye contact. Ingestion is not considered likely due to the gaseous state of the chemical. 

Inhalation of chloromethane may cause inflammation and irritation of the respiratory system as well as other serious and irreversible damage. Chloromethane produces only slight nervous system depression, with severe nausea and vomiting symptoms at first. For more lethal exposures, the brain, lungs, kidneys and liver are all affected.   

Other symptoms include headache, dizziness, drowsiness, confusion, sleepiness, tremors, spasms, paralysis, personality changes, blurred vision, increased body temperature and others. 

 Although chloromethane is not thought to be a skin irritant, prolonged exposure to the skin may result in temporary discomfort and good hygiene practices are recommended to ensure exposure is minimised. Entry into the bloodstream through open cuts and wounds may also lead to other harmful effects. Chloromethane vapours can cause cold burns and frostbite, with symptoms including pins and needles, paleness/numbness, stiffening of the skin and colour changes in the skin.  

Due to its gaseous state, it is not likely to cause eye irritation, however direct eye contact with the chemical may cause discomfort, tearing and redness.

Chloromethane Safety

If inhaled, remove the patient from the contaminated area to the nearest fresh air source. If the patient is not breathing and you are qualified to do so, perform CPR, preferably with a bag-valve mask device to ensure the safety of the rescuer. Continuously monitor their breathing and pulse. Seek medical attention. 

If skin exposure occurs, immediately remove all contaminated clothing and footwear and flush the affected area with plenty of soap and running water. In cases of cold burns, or frostbite, move the patient to a warm area before thawing the affected part. The affected area should be bathed in lukewarm water for 10 to 15 minutes. Seek medical attention.

If the chemical is exposed to the eyes, remove the patient from the contaminated area and take to the nearest eye wash station or emergency shower. Open the eyelids wide to allow the chemical to evaporate. Flush the eyes out with fresh running water for at least 15 minutes, remembering to wash under the eyelids. Removal of contact lenses should only be done by a skilled individual. Transport to hospital. 

Chloromethane Safety Handling

Emergency eyewash fountains should be accessible in the immediate area of the potential exposure to the chemical. Proper ventilation is essential in removing and diluting any air contaminants. If natural ventilation is unavailable, ensure local exhaust is installed. 

The PPE recommended when handling chloromethane includes chemical goggles, full face shields, respirators, full body protective suits, safety footwear, protective overalls and cloth or leather gloves. 

Always check the SDS to provide you with the most current and detailed advice for handling chloromethane. Click here for a trial of our SDS Management Software or contact us at sa***@ch*******.net for more information about our chemicals management solutions. 

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