Description
MTBE is a volatile organic compound (VOC), with a strong odor, which is added to gasoline to increase its oxygen content to reduce carbon monoxide emissions from car exhaust. MTBE has been used since 1979. But, after the passage of the 1990 Clean Air Act, the federal government required that regions of the U.S. that did not meet federal air pollution standards use gasoline containing oxygenates (such as MTBE or ethanol) during winter months, when carbon monoxide emissions are highest.
Soon after, some motorists reported health effects from MTBE, such as headache and nausea, while driving or refueling. MTBE has also become a widespread contaminant of drinking water due to leaks from underground storage tanks. Some states have already banned MTBE.Ethanol has replaced MTBE as an additive for gasoline in many areas.
It is also used to treat gallstones. Doctors inject it directly into the patient’s gallbladder through surgically implanted tubes.
Health Effects
Immediate Health Effects
- If SWALLOWED, methyl tert butyl ether is Very Highly Toxic
- If ABSORBED THROUGH SKIN, methyl tert butyl ether is Highly Toxic
- If INHALED (SNIFFED OR BREATHED IN), methyl tert butyl ether is Highly Toxic
Longterm or Delayed Health Effects
- This chemical is considered an Unclassifiable Carcinogen by the World Health Organization, the U.S. Environmental Protection Agency, or another agency.
- Neurotoxin = Can harm brain and central nervous system
- Asthma Trigger
Other
- Fumes can irritate the eyes, nose and throat.
- Nervous system depression, causing headaches, nausea, dizziness, weakness, confusion, and difficulty concentrating.
- Kidney and liver damage.
- Test animals exposed to high doses of MTBE have developed leukemia, lymphoma, and liver, kidney, and testicular cancer.
- In offspring of test animals exposed during pregnancy, MTBE has increased the incidence of cleft palate and of low body weight and low survival rate.
How Exposures Occur
Automobile Exhaust
- Children can inhale MTBE fumes in car, truck, and airplane exhaust when travelling as a passenger inside vehicles or when breathing outdoor air near busy roadways in regions of the U.S. where MTBE is added to fuel.
Drinking Water
- Children can be exposed to MTBE when they drink or swim or shower in contaminated water. MTBE can contaminate groundwater from leaking underground gasoline storage tanks and pipelines, spills, and emissions from marine engines into lakes. Once released into the environment, it remains in groundwater for a long time.
Gasoline Fumes
- Children can inhale MTBE fumes from gasoline at filling stations, if gas is stored in home garages, or if they live near filling stations or other facilities that can leak gasoline from underground storage containers.
Significant Statistics
The EPA estimates that reformulated gasoline (containing oxygenates such as MTBE or ethanol) has reduced smog forming pollutants by 105 thousand tons annually and toxics by at least 24 thousand tons annually.
MTBE Overview: FAQs. U.S. Environmental Protection Agency. November 24, 2008. http://www.epa.gov/mtbe/faq.htm
Originally, MTBE replaced lead as an octane enhancer to prevent engine knocking. At higher concentrations, it helps gasoline meet the Clean Air Act requirements.
MTBE & Ethanol. Texas State Energy Conservation Office. http://www.seco.cpa.state.tx.us/re_ethanol_mtbe.htm.
Solutions
How to detect methyl tert butyl ether
- To find out whether the gasoline in your region may contain MTBE, see the listing of oxygenated fuels used in each locality at the U.S. Environmental Protection Agency’s MTBE website.
- In 2001, the U.S. EPA began requiring that public water systems serving most of the population monitor for MTBE. To find out whether MTBE has been detected in your public water supply, contact your local water supplier. You can also have your water tested by sending samples to a certified laboratory. The EPA has compiled a list of state-certified drinking water laboratories.
If you draw your water from a private well, the local health department may be able to tell you if MTBE is a water contaminant in your area. If it has not been tested, and if your well is near a filling station, you may want to have your water tested for MTBE contamination. For more information on testing, go to EPA’s Safe Drinking Water web site, or call the Safe Drinking Water Hotline, 800-426-4791.
How to minimize exposure to methyl tert butyl ether
- Some water filters remove MTBE. You can search for water filtration devices that have been certified to remove MTBE by doing a search on National Sanitation Foundation Certified Product Listings.
Alternatives
- Service stations with plastic vapor-recovery boot nozzles on their gas pumps release less fumes, including MTBE, into the air during filling. Look for this accordion-like cover over the pump nozzle.
- Urge your local gas stations to oxygenate their fuel with safer ethanol instead of MTBE.
For More information
Books, articles, factsheets and reports
MTBE in Drinking Water. U.S. Environmental Protection Agency, Office of Water, Ground Water and Drinking Water.
http://www.epa.gov/safewater/mtbe.html
Other government agencies
U.S. Environmental Protection Agency
Office of Ground Water and Drinking Water
Ariel Rios Building
1200 Pennsylvania Avenue, NW
Washington DC 20460-0003
EPA Safe Drinking Water Hotline: 800-426-4791
http://www.epa.gov/mtbe
Agency for Toxic Substances and Disease Registry
Division of Toxicology
1600 Clifton Road NE, Mailstop E-29
Atlanta, GA 30333
800-447-1544
http://www.atsdr.cdc.gov
Texas State Energy Conservation Office.
http://www.seco.cpa.state.tx.us/re_ethanol_mtbe.htm
Nonprofit organizations
Other websites
Environmental Defense Chemical Scorecard
http://www.scorecard.org
