The Methyl Bromide Phase Out
Toxic air pollutants not only impart negative effects on humans, they also have a detrimental effect on the ozone layer. The ozone layer is important as it protects the environment and human health from the full brunt of the sun’s ultraviolet rays.
In 1987, 190 countries signed the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) and committed themselves to the statements outlined in the protocol; mainly to eliminate chemicals that destroy the ozone. Among the Protocol signers was the United States. As part of the plan, the US amended the Clean Air Act to increase its scope to include the protection of the ozone layer. One of the listed chemicals slated for elimination was Methyl Bromide.
Methyl Bromide, also known as bromomethane, is an odorless, colorless, and non flammable gas that was being extensively used as a pesticide and soil fumigant. The immediate elimination of Methyl Bromide turned out to be a challenge. The chemical was widely used and finding effective alternatives proved difficult. The original phase out schedule for Methyl Bromide in the US can be seen on this USEPA website. The Protocol called for a complete phase out of the organo-halogen by 2005, with the exception of allowable exemptions. The Critical Use Exemptions in the United States has been decreasing since the 2005 deadline.
Alternatives to Methyl Bromide
Scientists in Gainesville studying alternates to methyl bromide recommended using a virtually impermeable film to hold soil fumigants in the soil. This strategy allows farmers to use smaller amounts of fumigants.
The USEPA offers a comprehensive list of current methyl bromide alternatives.
To search for methyl bromide alternative projects by state, visit the U.S. Department of Agriculture/Agricultural Research Service’s methyl bromide alternative website.
The Methyl Bromide Alternative Outreach organizes an annual conference to help in the disseminating of research and information into methyl bromide alternatives and emissions reduction.
Other Resources
Information on using methyl bromide to decontaminate anthrax spores.
Medical Management Guidelines for Methyl Bromide by the Agency for Toxic Substances & Disease Registry.
Treatment for Methyl Bromide poisoning.
EXTOXNET database entry on methyl bromide as archived at Oregon State University. The page includes information of the chemical's toxicological effects and environmental fate.
