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 Also known as: Toluol, Methylbenzene, Phenylmethane
Chemical reference number (CAS): 108-88-3

Toluene is a common ingredient in degreasers. It's a colorless liquid with a sweet smell and taste. It evaporates quickly. Toluene is found naturally in crude oil, and is used in oil refining and the manufacturing of paints, lacquers, explosives (TNT) and glues. In homes, toluene may be found in paint thinners, paintbrush cleaners, nail polish, glues, inks and stain removers. Toluene is also found in car exhaust and the smoke from cigarettes.

When toluene is spilled on the ground or improperly disposed of, it can seep into soil and contaminate nearby wells and streams. Toluene can remain unchanged for a long time in soil or water that is not in contact with air.

People are often exposed to high levels of toluene when they breathe vapors from paints, paint thinners, or glues. Breathing gasoline or car exhaust will also result in some exposure to toluene. People who live near industries using toluene may be exposed to the chemical in the air. If home water supplies are contaminated, people may inhale the chemical while washing, bathing or using water for other household purposes.

Some people intentionally inhale toluene to get "high." These people can be exposed to hazardous levels of the chemical.

People may be exposed by drinking contaminated water, handling contaminated soils, or touching their mouths or eating with dirty hands.

Although the chemical may irritate the skin, it passes through the skin slowly. People can be exposed to toluene when they touch the chemical, touch contaminated soil, or bathe in contaminated water.

No standards exist for regulating the amount of toluene allowed in the air of homes. However, the Wisconsin Department of Natural Resources (DNR) has set a residential indoor air action level for toluene at 1,400 parts per billion by volume (ppbv). The action level is considered to be protective of public health. Breathing toluene for a lifetime at 1,400 ppbv is very unlikely to be harmful to people. If toluene concentrations in air are above the action level, we recommend taking action to halt exposure.

Most people can smell toluene at levels between 160 and 37,000 ppbv. If you can smell the chemical, the level may be too high to be safe.

The Wisconsin Department of Natural Resources regulates the amount of toluene that can be released into outdoor ambient air by industries.

The Wisconsin drinking water standard is 800 parts per billion (ppb) of toluene. We suggest you stop drinking water that contains higher levels. If levels of toluene are very high in your water, you should avoid washing, bathing, or using the water for other purposes as well. Contact your local public health department for more information specific to your situation.

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.

The following symptoms may occur immediately or shortly after exposure to levels over 100,000 ppbv of toluene in air:

  • Tiredness, dizziness, headache, loss of coordination or hearing, euphoria, insomnia
  • Nausea
  • Eye and nose irritation
  • Rapid delay of reaction time, unconsciousness, and death at levels of 4,000 ppm (4,000,000 ppbv)

The worst effects of exposure to toluene have occurred in deliberate abusers of toluene. Most studies of workers exposed to moderate levels of toluene show no harmful health effects.

The breakdown products of toluene, hippuric acid and cresol, can be measured in urine within 12 hours of a high-level exposure. These measurements may not predict possible future health effects. Other medical tests may be helpful in determining damage to the nervous system, kidneys or liver.

Seek medical advice if you have any symptoms that you think may be related to chemical exposure.

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Last revised June 15, 2022