Methyl bromide (bromomethane) is a colourless, non-flammable gas with no taste or odour at low concentration. It's used in agriculture and for quarantine treatments.
Exposure to dichloromethane mainly occurs through inhalation or direct contact through the eyes and skin.
Where possible you should not use dichloromethane, or use other, safer products that don’t contain it.
If you have to work with dichloromethane you must:
- use the lowest amounts possible
- use ventilation
- only allow licensed fumigators to use it for fumigation
- avoid decanting, if you do, re-label correctly
- vent shipping containers before entering
- recapture fumes
- use the right personal protective equipment (PPE), eg respirators, goggles and chemical resistant gloves
- train workers to fit, use and maintain PPE
- have safety equipment available, eg eye wash and showers
- do air monitoring regularly
- always follow the advice in safety data sheets and on product labels.
In the event of suspected exposure, call the Poisons Information Centre on 131 126
Methyl bromide is usually stored as a liquid under pressure in steel cylinders or small sealed cans. It 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 one of these 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.
Methyl bromide is a highly toxic chemical that is difficult to smell. The potential for harm depends on concentration and duration of use. Short term exposure to methyl bromide 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 (eg 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 in to 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.
More detail can be found in our methyl bromide technical fact sheet.
In the event of suspected exposure, call the Poisons Information Centre on 131 126.