Gasoline

This fact sheet provides answers to questions about gasoline. It will explain what gasoline is, how you can be exposed to it, how it can make you sick, and ways to reduce or prevent your exposure to gasoline.

Gasoline is made from processed crude oil and is a pale brown or pink liquid with a strong odor. It evaporates easily, is very flammable and can form explosive mixtures in air. Typical gasoline contains about 150 different chemicals, including benzene, toluene, ethylbenzene and xylene, which also are known as the BTEX compounds.

Gasoline also contains chemicals such as lubricants, anti-rust agents and anti-icing agents that are added to improve car performance. These chemicals usually are only present in very small amounts. Before the 1980s, lead was commonly used in gasoline as an anti-knocking agent. The use of lead has been stopped due to air pollution and the possibility of adverse health effects. Some gasolines also contain ethanol, which is made from corn. Ethanol helps a car run more efficiently and it produces less pollution. The most common additive used in gasoline is methyl tertiary-butyl ether (MTBE). It is added to increase octane and oxygen levels and reduce pollution emissions.

Spills, leaks or improper disposal of gasoline can cause contamination of soil, groundwater, surface water and air. Leaking underground storage tanks or pipelines also can cause gasoline to enter surrounding soil and groundwater. Gasoline can be released into the air when large tanker trucks are filled and emptied and when you fill your car at the service station.

You can be exposed to gasoline by —

• breathing gasoline vapors,
• drinking water contaminated with gasoline, or
• touching gasoline or soil or water contaminated with gasoline.

The most common exposure to gasoline occurs by breathing vapors when filling your car’s fuel tank. Vapors also can be present in air when gasoline evaporates out of contaminated soil or water. Gasoline vapors can build up in basements, crawlspaces and living areas.

When gasoline seeps into soil, it can contaminate groundwater used for drinking. Most chemicals in gasoline are removed during water treatment, but people who drink untreated water or water from private wells can be exposed. Gasoline also can be absorbed through skin during contact, such as when pumping gas or cleaning up a gasoline spill.

Many adverse health effects of gasoline are due to individual chemicals in gasoline, mainly BTEX, that are present in small amounts. Breathing small amounts of gasoline vapors can lead to nose and throat irritation, headaches, dizziness, nausea, vomiting, confusion and breathing difficulties. Symptoms from swallowing small amounts of gasoline include mouth, throat and stomach irritation, nausea, vomiting, dizziness and headaches. Some effects of skin contact with gasoline include rashes, redness and swelling. Being exposed to large amounts of gasoline can lead to coma or death.

The health effects of being exposed to gasoline over long periods of time are not well known. This is because people exposed to gasoline are usually exposed to many other things that also can cause health effects. Some workers who are exposed to gasoline every day in their jobs have suffered memory loss and decreased muscle function. At very high levels, some of the chemicals in gasoline, such as benzene, are known to cause cancer. Current evidence, however, does not show that exposure to low levels of gasoline causes cancer in humans.

There are laboratory blood or urine tests that can determine if you have been exposed to gasoline, but these tests are not generally available in your doctor’s office. These tests measure BTEX compounds in your body, which may be present as a result of exposure to sources other than gasoline.

Due to the widespread use of gasoline in cars, trucks, buses and lawn care equipment, eliminating exposure would be difficult. Typically, you can smell gasoline at levels that would not be expected to cause adverse health effects. Since gasoline can be smelled at low levels, the source can usually be found and eliminated.

If you suspect that your water supply is contaminated with gasoline, here are a few ways to reduce your exposure:

• If gasoline is in your well water, do not drink it. Consider using bottled water for drinking and cooking, using a water treatment unit certified to remove gasoline chemicals, or connecting to a public water supply.
• Shower or wash in cooler water. Wash and rinse clothes in cold water. The hotter the water, the more gasoline evaporates into the air you breathe.
• Air out bathrooms, washrooms and kitchens during and after water use by opening doors and windows and turning on exhaust fans.

Illinois Department of Public Health

Division of Environmental Health

525 W. Jefferson St.

Springfield, IL 62761

217-782-5830

TTY (hearing impaired use only) 800-547-0466

This fact sheet was supported in part by funds from the Comprehensive Environmental Response, Compensation, and Liability Act trust fund through a cooperative agreement with the Agency for Toxic Substances and Disease Registry, Public Health Service, U.S. Department of Health and Human Services.