Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.


Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Chemicals: Gasoline

Also known as: Gas, Motor Spirit, Motor Fuel, Petrol, Essence
Chemical reference number (CAS): 8006-61-9

Gasoline is a mixture of about 150 chemicals refined from crude oil. It is usually a colorless, light brown or pink liquid. Gasoline is used in cars, boats, motorcycles, lawn mowers and other engines. Gasoline usually contains additives, like MTBE, affecting the way it burns.

Gasoline evaporates quickly when exposed to air. Most gasoline spilled in lakes, streams, or soil evaporates. Some spilled gasoline can seep into groundwater and remain unchanged for years. Private wells located near a spill or a buried leaking tank may become contaminated. Scientists refer to gasoline components that mix with water as gasoline range organics (GRO).

Exposure occurs when people breathe gasoline vapors while filling gas tanks or intentionally inhaling gasoline vapors to get "high."

Exposure may also occur when using contaminated water to bathe or do laundry. However, the exposure when using contaminated water for drinking or preparing food is usually low. Some ingredients in gasoline can pass through the skin when gasoline is used as a cleaner or accidentally spilled on skin or clothing.

No standards exist for the amount of gasoline-related chemicals allowed in the air of homes. However, the Wisconsin Department of Natural Resources (DNR) has set residential indoor air action levels for some of the chemicals that make up gasoline's mixture, including: benzene (0.95 parts per billion volume or ppbV), ethyl benzene (2.2 ppbV), toluene (1,400 ppbV), and xylene (23 ppbV).

Most people can smell gasoline at levels as low as 250 ppbV. If you can smell gasoline in your home, there is a potential health hazard. To prevent irritation and health effects to the nervous system, we suggest you store gasoline outside of your home. This also reduces fire hazards and the amount of vapors entering your home.

Gasoline vapors are heavier than air, so dangerous levels can build up in basements and in other low areas where its stored indoors. An explosion is possible if the vapors are lit by a spark or flame, such as the pilot light in a water heater, stove, or furnace.

Although no standard exists for gasoline in drinking water, there are standards for some of the chemicals that make up gasoline's mixture. The standard for benzene (2% of the gasoline mixture) is 5 parts per billion (ppb), ethyl benzene is 700 ppb, toluene is 800 ppb, and xylene is 2 parts per million (ppm). We suggest you stop drinking or cooking with water containing any chemical above the standard, if you can smell a gasoline odor or see a oily sheen. If the chemicals occur at very high levels in your drinking water, you should avoid washing, bathing or using the water for other purposes as well.

Everyone's reaction is different

A person's reaction to chemicals depends on several things, including individual health, heredity, previous exposure to chemicals including medicines, and personal habits such as smoking or drinking. It’s also important to consider the length of exposure to the chemical, the amount of chemical exposure, and whether the chemical was inhaled, touched, or eaten.

Immediately or shortly after breathing a high amount of gasoline, a person may experience nose or lung irritation, feel dizzy or have a headache. When swallowed, gasoline will cause stomach irritation. Drinking gasoline or inhaling concentrated vapors can result in death.

The following health effects can occur after several years of exposure to low levels of gasoline in air or in water:

  • There is no evidence that exposure to gasoline causes cancer in humans. However, long-term exposure to high levels of benzene, a component of gasoline, may increase a person's risk of leukemia.
  • People can experience damage to the nervous system or lungs.

The chemicals in gasoline are quickly flushed from the body. Although some of these chemicals can be measured in exhaled breath, urine, blood, and other tissues, these tests may not be helpful in predicting health effects. Your doctor can use function tests of your lungs, nervous system and heart to evaluate the effects of gasoline exposure.

Questions? Can't find what you're looking for? Email:

Last revised August 28, 2023