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ToxFAQs™ for Bromomethane
CAS#: 74-83-9
This fact sheet answers the most frequently asked health questions about bromomethane. For more information, you may call the ATSDR Information Center at 1-888-422-8737. This fact sheet is one in a series of summaries about hazardous substances and their health effects. It is important you understand this information because this substance may harm you. The effects of exposure to any hazardous substance depend on the dose, the duration, how you are exposed, personal traits and habits, and whether other chemicals are present.
What is bromomethane?
Bromomethane (also called methyl bromide) is a colorless, odorless gas. Some bromomethane is formed in the ocean, probably by algae or kelp; after it is formed, it is likely to move into the air.
The main use of bromomethane is to make other chemicals. In the past, bromomethane was used in professional agricultural settings to control insects, rodents, and fungi. However, because bromomethane depletes the ozone layer, its production and use was phased out in the United States in 2005, and the U.S. Environmental Protection Agency (EPA) only allows very limited uses of bromomethane.
How can I be exposed to bromomethane?
Because bromomethane is a gas, you are most likely to be exposed by breathing it in air. Exposure to inhaled bromomethane is more likely to occur in workers than in the general population.The general population is not likely to be exposed to bromomethane by ingestion (eating or drinking it). However, very small amounts of bromomethane may be found in food and water.
The levels of bromomethane found in the environment are generally lower than levels known to cause health problems.
How can bromomethane affect my health?
Breathing bromomethane can harm your respiratory tract (nose and lungs) and nervous system. In workers, bromomethane in air has caused damage to the lungs and signs of nervous system damage, such as dizziness, muscle weakness, and seizures. Similar effects were seen in laboratory animals. These effects were found at higher levels than those found in the environment.
In workers, bromomethane vapor can irritate eyes and skin.
In a study in pregnant rabbits exposed by breathing bromomethane in air, offspring were smaller and had some birth defects. However, we do not know if bromomethane causes birth defects in humans.
The effects found in animals happened at bromomethane levels much higher than what humans normally are exposed to in the environment.
How can bromomethane affect children?
The health effects of bromomethane exposure in children are not known. However, it is expected to cause the same effects in children as it does in adults.
Can bromomethane cause cancer?
Studies in laboratory animals breathing in or swallowing bromomethane for a long period of time did not find any cancer.
The Department of Health and Human Services (HHS) has not classified bromomethane for carcinogenicity (causing cancer) in humans. The International Agency for Research on Cancer (IARC) and the EPA have determined that bromomethane is not classifiable as to human carcinogenicity.
Can I get a medical test to check for bromomethane?
A blood test is available to measure levels of bromide in the body. However, this test cannot tell you if the bromide comes from exposure to bromomethane or bromide in other chemicals. This test cannot predict whether you will experience any health effects. Doctor’s offices do not routinely offer these tests.
How can I protect myself and my family from bromomethane?
Most people don’t need to take any special steps to avoid bromomethane in their daily lives. If you live near a place where bromomethane is used, you should avoid spending time close to the site.
Where can I get more information?
If you have questions or concerns, please contact your community or state health or environmental quality department or:
For more information, contact:
Agency for Toxic Substances and Disease Registry
Division of Toxicology and Human Health Sciences
1600 Clifton Road NE, Mailstop S102-1
Atlanta, GA 30333
Phone: 1-800-CDC-INFO · 888-232-6348 (TTY)
Email: Contact CDC-INFO
ATSDR can also tell you the location of occupational and environmental health clinics. These clinics specialize in recognizing, evaluating, and treating illnesses resulting from exposure to hazardous substances.
- Page last reviewed: March 3, 2011
- Page last updated: March 12, 2020
- Content source: Agency for Toxic Substances and Disease Registry

