bromomethane

Bromomethane, also known as methyl bromide, is the simplest alkyl bromide with the chemical formula CH3Br. It is a colorless, highly volatile gas at room temperature with a boiling point of about −24.2 °C. It is primarily produced industrially by the reaction of methanol with hydrobromic acid in the presence of a catalyst, yielding methyl bromide and water. It is also generated as a byproduct in some chemical processes and occurs in trace natural emissions from oceanic and soil sources.

In commerce, bromomethane has been used extensively as a soil and structural fumigant, as a quarantine and pre-shipment treatment for agricultural goods, and as a general pesticide. Due to its high toxicity to humans and animals, its use requires strict controls and protective measures.

Environmental and safety profile: Methyl bromide is an ozone-depleting substance with a high ozone depletion potential. It releases bromine radicals in the stratosphere, contributing to ozone layer thinning. It is also a potent greenhouse gas with significant global-warming potential. Because of these effects, its production and use have been heavily restricted under the Montreal Protocol, with phase-out for most uses and continued exemptions only for critical quarantine and pre-shipment applications.

Chemically, bromomethane is relatively reactive; it hydrolyzes slowly in water to methanol and hydrobromic acid. It is highly toxic via inhalation and contact, posing acute respiratory and neurological hazards. Handling requires proper ventilation and protective equipment.