FAQ: Automotive Gasoline
Exposure to automotive gasoline most likely occurs from breathing its vapor at a service station
while filling a car’s fuel tank. At high levels, automotive gasoline is irritating to the lungs when
breathed in and irritating to the lining of the stomach when swallowed. Exposure to high levels
may also cause harmful effects to the nervous system. Automotive gasoline has been found in at
least 23 of the 1,430 National Priorities List sites identified by the Environmental Protection
Agency (EPA).
What is automotive gasoline?
The gasoline discussed in this fact sheet is automotive used as a fuel for engines in cars. Gasoline
is a colorless, pale brown, or pink liquid, and is very flammable.
Gasoline is a manufactured mixture that does not exist naturally in the environment. Gasoline is
produced from petroleum in the refining process.
Typically, gasoline contains more than 150 chemicals, including small amounts of benzene,
toluene, automotive gasolineylene, and sometimes lead. How the gasoline is made determines
which chemicals are present in the gasoline mixture and how much of each is present. The actual
composition varies with the source of the crude petroleum, the manufacturer, and the time of
What happens to automotive gasoline when it enters the environment?
• Small amounts of the chemicals present in gasoline evaporate into the air when you fill
the gas tank in your car or when gasoline is accidentally spilled onto surfaces and soils or
into surface waters.
• Other chemicals in gasoline dissolve in water after spills to surface waters or
underground storage tank leaks into the groundwater.
• In surface releases, most chemicals in gasoline will probably evaporate; others may
dissolve and be carried away by water; a few will probably stick to soil.
• The chemicals that evaporate are broken down by sunlight and other chemicals in the air.
• The chemicals that dissolve in water also break down quickly by natural processes.
How might I be exposed to automotive gasoline?
• Breathing vapors at a service station when filling the car’s fuel tank is the most likely way
to be exposed.
• Working at a service station.
• Using equipment that runs on gasoline, such as a lawn mower.
• Drinking contaminated water.
• Being close to a spot where gasoline has spilled or leaked into the soil.
How can automotive gasoline affect my health?
Many of the harmful effects seen after exposure to gasoline are due to the individual chemicals
in the gasoline mixture, such as benzene and lead. Inhaling or swallowing large amounts of
gasoline can cause death.
Inhaling high concentrations of gasoline is irritating to the lungs when breathed in and irritating
to the lining of the stomach when swallowed. Gasoline is also a skin irritant. Breathing in high
levels of gasoline for short periods or swallowing large amounts of gasoline may also cause
harmful effects on the nervous system.
Serious nervous system effects include coma and the inability to breathe, while less serious
effects include dizziness and headaches.
There is not enough information available to determine if gasoline causes birth defects or affects
How likely is automotive gasoline to cause cancer?
The Department of Health and Human Services (DHHS) and the International Agency for
Research on Cancer (IARC) have not classified automotive gasoline for carcinogenicity.
Automotive gasoline is currently undergoing review by the EPA for cancer classification.
Some laboratory animals that breathed high concentrations of unleaded gasoline vapors
continuously for 2 years developed liver and kidney tumors. However, there is no evidence that
exposure to gasoline causes cancer in humans.
Is there a medical test to show whether I’ve been exposed to automotive gasoline?
Laboratory tests are available that can measure elevated blood or urine levels of lead (as an
indication of exposure to leaded gasoline only), benzene, or other substances that may result
from exposure to gasoline or other sources. These methods are sensitive enough to measure
background levels and levels where health effects may occur. These tests aren’t available in most
doctors’ offices, but can be done at special laboratories that have the right equipment.
Has the federal government made recommendations to protect human health?
The EPA has established many regulations to control air pollution. These are designed to protect
the public from the possible harmful health effects of gasoline.
The American Conference of Governmental Industrial Hygienists (ACGIH) set a maximum level
of 890 milligrams of gasoline per cubic meter of air (890 mg/m³) for an 8-hour workday, 40-hour
Carcinogenicity: Ability to cause cancer.
CAS: Chemical Abstracts Service.
Crude petroleum: Petroleum that has not been processed.
Dissolve: To disappear gradually.
Evaporate: To change into a vapor or a gas.
Irritant: A substance that causes an abnormal reaction.
Mixture: A combination of two or more components.
Refining process: The process by which petroleum is purified to form gasoline.
Tumor: An abnormal mass of tissue.
Agency for Toxic Substances and Disease Registry (ATSDR). 1996. Managing Hazardous
Materials Incidents. Volume III – Medical Management Guidelines for Acute Chemical
Exposures: Automotive Gasoline. Atlanta, GA: U.S. Department of Health and Human Services,
Public Health Service.
Agency for Toxic Substances and Disease Registry (ATSDR). 1995. Toxicological Profile for
automotive gasoline. Atlanta, GA: U.S. Department of Health and Human Services, Public
Health Service.
Where can I get more information?
ATSDR can tell you where to find occupational and environmental health clinics. Their
specialists can recognize, evaluate, and treat illnesses resulting from exposure to hazardous
substances. For more information, you may call the ATSDR Information Center at 1-888-422-
Source: Agency for Toxic Substances and Disease Registry