Methyl bromide
A general fact sheet to help businesses (PCBU) manage the risks of Methyl Bromide (bromomethane), also called methylene chloride, in the workplace.
Methyl Bromide is a colourless, non-flammable gas which has no taste or odour at low concentration. It is usually stored as a liquid under pressure in steel cylinders or small sealed cans.
Chloropicrin, a tearing agent, is often added to Methyl Bromide to give off a strong, sharp and highly irritating odour so that it is possible to detect the presence of Methyl Bromide without special equipment.
Read our Methyl Bromide Technical Fact Sheet.
Uses
Methyl Bromide has been widely used as a fumigant in pest control. Its primary uses are for soil fumigation, post-harvest protection and quarantine treatments.
Methyl Bromide’s use has been severely restricted under the Montreal Protocol which is a global agreement to protect the ozone layer by phasing out the production and consumption of ozone-depleting substances (ODS). Methyl Bromide is classified as an ODS. There are ‘essential use’ exemptions in place in many countries, including Australia.
Workers who are mostly at risk include fumigators, quarantine contractors and those unpacking shipping containers.
Harms
Methyl Bromide is a highly toxic chemical which is difficult to smell. Exposure is most often through inhalation and absorption through the skin. Depending on factors such as the concentration and duration of use, exposure can result in different degrees of harm to workers.
Short term exposure can cause:
- headache, dizziness,
- nausea, vomiting,
- blurred vision, slurred speech, and convulsions.
Acute exposure at high concentrations may be fatal. Injuries include:
- severe chemical burns of the skin, eyes and airways,
- delayed chemical pneumonia which produces water in the lungs, (pulmonary oedema),
- severe kidney damage,
- damage to the central nervous system, including vision.
Chronic long-term exposure can cause loss of muscle function and memory impairment. Low level chronic exposure causes a general degeneration of peripheral nerves that spreads towards the centre of the body.
Methyl Bromide gas easily penetrates most protective clothing (e.g. cloth, rubber and leather). Repeated skin exposure may cause contact dermatitis.
Methyl Bromide gas is heavier than air. It can pool in the back of containers, diffuse into tightly packed or sealed cartons, or even become trapped in gloves, boots or other clothing. Adequate controls such as allowing the gas to evaporate before entering treated areas and the use of appropriate personal protective equipment (PPE) can minimise hazardous exposures and prevent illness.
Controls
SafeWork NSW recommends you follow a hierarchy of controls to eliminate or minimise a hazard.
Eliminate use if possible
Eliminate the use of Methyl Bromide if reasonably practicable.
Other controls
- Use the lowest amount necessary.
- Ensure adequate engineering controls including adequate ventilation.
- When used as a fumigant, employers must ensure that fumigation is carried out by a licensed fumigator.
- Avoid inhalation, skin and eye contact by wearing appropriate respiratory protection along with chemical-resistant gloves and goggles; and other PPE deemed necessary.
- Instruct and train workers in the correct fitting, use and maintenance of PPE.
- Decanting should be avoided. If Methyl Bromide is decanted to a new container, it must be properly labelled.
- When unpacking shipping containers, the containers must be vented of Methyl Bromide before workers enter them. Any Methyl Bromide vented from the container should preferably be captured using recapture technology.
- Follow instructions and controls outlined in Safety Data Sheets and product labels.
Ensure that instructions and controls outlined in Safety Data Sheets, manufacturers specifications, product labels and any instructions provided by supervisors and managers are followed.
More information
- In the event of suspected exposure, call the Poisons Information Centre on 131 126.
- Our Methyl Bromide Technical Fact Sheet has more information or call us on 13 10 50.